### Run Example App

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/README.md

Navigate to the example directory and run the Flutter app to see the plugin in action. This demonstrates various usage scenarios, error handling, and platform-specific behaviors.

```bash
cd example
flutter run
```

--------------------------------

### Custom Platform Implementation Example

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreviewPlatform.md

Demonstrates how to create and register a custom implementation of the NativeFilePreviewPlatform interface.

```APIDOC
## Default Implementation

The default implementation is `MethodChannelNativeFilePreview`, which communicates with native code via a method channel named `native_file_preview`.

#### Example of Creating a Custom Platform Implementation

```dart
import 'package:native_file_preview/native_file_preview_platform_interface.dart';

class CustomNativeFilePreview extends NativeFilePreviewPlatform {
  @override
  Future<String?> getPlatformVersion() async {
    // Custom implementation
    return 'custom_1.0.0';
  }

  @override
  Future<void> previewFile(String filePath) async {
    // Custom implementation
    // Could use a different communication method, caching strategy, etc.
  }
}

// Register the custom implementation
void main() {
  NativeFilePreviewPlatform.instance = CustomNativeFilePreview();
  runApp(MyApp());
}
```
```

--------------------------------

### Preview File Example

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreview.md

Demonstrates how to use the previewFile method to open a local file. Includes error handling for PlatformException.

```dart
import 'package:native_file_preview/native_file_preview.dart';

class FilePreviewScreen extends StatefulWidget {
  @override
  _FilePreviewScreenState createState() => _FilePreviewScreenState();
}

class _FilePreviewScreenState extends State<FilePreviewScreen> {
  final _nativeFilePreview = NativeFilePreview();

  void _previewFile() async {
    try {
      // Preview a local file
      await _nativeFilePreview.previewFile('/path/to/document.pdf');
    } on PlatformException catch (e) {
      _showErrorDialog('Preview Error', e.code, e.message);
    }
  }

  void _showErrorDialog(String title, String code, String? message) {
    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: Text(title),
        content: Text('Error: $code\n${message ?? "Unknown error"}'),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(context),
            child: Text('OK'),
          ),
        ],
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return ElevatedButton(
      onPressed: _previewFile,
      child: Text('Preview PDF'),
    );
  }
}
```

--------------------------------

### Development Setup - Git Workflow

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/README.md

Follow these steps to set up the development environment, contribute changes, and submit pull requests for the native_file_preview plugin.

```bash
git checkout -b feature/amazing-feature
```

```bash
git commit -m 'Add some amazing feature'
```

```bash
git push origin feature/amazing-feature
```

--------------------------------

### Custom Platform Implementation Example

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreviewPlatform.md

Demonstrates how to create and register a custom implementation of NativeFilePreviewPlatform, overriding its abstract methods.

```dart
import 'package:native_file_preview/native_file_preview_platform_interface.dart';

class CustomNativeFilePreview extends NativeFilePreviewPlatform {
  @override
  Future<String?> getPlatformVersion() async {
    // Custom implementation
    return 'custom_1.0.0';
  }

  @override
  Future<void> previewFile(String filePath) async {
    // Custom implementation
    // Could use a different communication method, caching strategy, etc.
  }
}

// Register the custom implementation
void main() {
  NativeFilePreviewPlatform.instance = CustomNativeFilePreview();
  runApp(MyApp());
}
```

--------------------------------

### Present Modal Preview Example

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFileViewerPreviewViewController-iOS.md

Demonstrates how to instantiate and present the NativeFileViewerPreviewViewController modally, providing a data source and a completion handler that prints a message when the preview is dismissed.

```swift
let previewController = NativeFileViewerPreviewViewController()
previewController.dataSource = someDataSource

previewController.presentModal(viewController: self) { result in
  print("Preview dismissed")
  // result is nil
}
```

--------------------------------

### FlutterMethodCall Usage Example

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/types.md

Demonstrates how to handle incoming method calls and access their method name and arguments.

```dart
void handle(FlutterMethodCall call, FlutterResult result) {
  // call.method: "previewFile"
  // call.arguments: {"file": "/path/to/file.pdf"}
}
```

--------------------------------

### Get Platform Version Example

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreview.md

Retrieves and prints the platform version using the getPlatformVersion method.

```dart
final version = await _nativeFilePreview.getPlatformVersion();
print('Platform Version: $version');
```

--------------------------------

### Preview File Example Flow

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreviewPlugin-iOS.md

Illustrates the interaction between the Dart layer and the Swift plugin for previewing a file. Shows the method call from Dart and how the Swift plugin receives and processes it.

```swift
// Dart layer calls:
// await NativeFilePreview().previewFile('/path/to/document.pdf');

// Swift receives:
FlutterMethodCall(
  method: "previewFile",
  arguments: ["file": "/path/to/document.pdf"]
)

// Plugin processes:
// 1. Validates file path is not nil
// 2. Converts "/path/to/document.pdf" to URL
// 3. Checks file exists and is readable
// 4. Creates NativeFileViewerPreview instance
// 5. Gets active view controller
// 6. Presents preview controller modally
// 7. Calls result(nil) when preview dismisses
```

--------------------------------

### Create and Start Intent

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/types.md

Construct an Intent object to perform an action, such as viewing a file. Use setDataAndType() to specify the URI and MIME type, and addFlags() to set necessary permissions and activity behaviors.

```kotlin
class Intent(action: String?, uri: Uri?) {
  fun setDataAndType(uri: Uri?, type: String?): Intent
  fun addFlags(flags: Int): Intent
}
```

```kotlin
val intent = Intent(Intent.ACTION_VIEW).apply {
  setDataAndType(uri, mimeType ?: "*/*")
  addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
  addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
}
activity.startActivity(intent)
```

--------------------------------

### MethodChannel Usage Example

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/types.md

Demonstrates invoking a method on the native platform using a MethodChannel. Ensure the channel name matches the native implementation.

```dart
final methodChannel = const MethodChannel('native_file_preview');

Future<void> previewFile(String filePath) async {
  await methodChannel.invokeMethod<void>('previewFile', {'file': filePath});
}
```

--------------------------------

### Correct Implementation of NativeFilePreviewPlatform

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/Platform-Interface-Pattern.md

Shows an example of a correctly implemented subclass that provides the required token to the superclass constructor and can be assigned to the platform instance.

```dart
class CorrectImpl extends NativeFilePreviewPlatform {
  CorrectImpl() : super(token: NativeFilePreviewPlatform._token); // ✓ Has token access
  // ...
}

NativeFilePreviewPlatform.instance = CorrectImpl(); // ✓ Works
```

--------------------------------

### Run flutter pub get

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/README.md

After adding the dependency to pubspec.yaml, run this command in your terminal to fetch the package.

```bash
flutter pub get
```

--------------------------------

### File Selection and Preview in Flutter

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/README.md

An advanced example showing how to use the file_picker package to let the user select a file, then preview it using NativeFilePreview. Includes error handling for both picking and previewing.

```dart
import 'package:native_file_preview/native_file_preview.dart';
import 'package:file_picker/file_picker.dart';

class AdvancedFilePreview extends StatefulWidget {
  @override
  _AdvancedFilePreviewState createState() => _AdvancedFilePreviewState();
}

class _AdvancedFilePreviewState extends State<AdvancedFilePreview> {
  final _nativeFilePreview = NativeFilePreview();

  Future<void> _pickAndPreviewFile() async {
    try {
      FilePickerResult? result = await FilePicker.platform.pickFiles();
      
      if (result != null) {
        String filePath = result.files.single.path!;
        await _nativeFilePreview.previewFile(filePath);
      }
    } on PlatformException catch (e) {
      _showErrorDialog('Preview Error', e.message ?? 'Unknown error');
    } catch (e) {
      _showErrorDialog('Unexpected Error', e.toString());
    }
  }

  void _showErrorDialog(String title, String message) {
    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: Text(title),
        content: Text(message),
        actions: [
          TextButton(
            onPressed: () => Navigator.of(context).pop(),
            child: Text('OK'),
          ),
        ],
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('Advanced File Preview')),
      body: Center(
        child: ElevatedButton(
          onPressed: _pickAndPreviewFile,
          child: Text('Pick and Preview File'),
        ),
      ),
    );
  }
}
```

--------------------------------

### PlatformException Usage Example

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/types.md

Shows how to catch and handle PlatformExceptions when method calls to the native layer fail.

```dart
try {
  await nativeFilePreview.previewFile(filePath);
} on PlatformException catch (e) {
  print('Error: ${e.code} - ${e.message}');
}
```

--------------------------------

### Integration Test Setup

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/configuration.md

Boilerplate for setting up integration tests with Flutter. Ensure integration_test package is initialized.

```dart
import 'package:integration_test/integration_test.dart';

void main() {
  IntegrationTestWidgetsFlutterBinding.ensureInitialized();
  
  testWidgets('Preview file integration test', (WidgetTester tester) async {
    // Your test code here
  });
}
```

--------------------------------

### Create ACTION_VIEW Intent for File Preview

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreviewPlugin-Android.md

Construct an Intent with ACTION_VIEW to open a file with the appropriate application. Use FLAG_GRANT_READ_URI_PERMISSION for temporary read access and FLAG_ACTIVITY_NEW_TASK to start in a new task.

```kotlin
val intent = Intent(Intent.ACTION_VIEW).apply {
  setDataAndType(uri, mimeType ?: "*/*")
  addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
  addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
}

activity.startActivity(intent)
```

--------------------------------

### iOS Swift XCTest Example

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/Platform-Interface-Pattern.md

An example of a unit test for the iOS native code using Swift's XCTest framework. This snippet illustrates testing file validation logic within the `NativeFilePreviewPlugin`.

```swift
func testFileValidation() {
  let plugin = NativeFilePreviewPlugin()
  // Test with mock file manager
}
```

--------------------------------

### Android Kotlin JUnit Example

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/Platform-Interface-Pattern.md

An example of a unit test for the Android native code using Kotlin's JUnit framework. This snippet demonstrates testing a scenario like file not found within the `NativeFilePreviewPlugin`.

```kotlin
@Test
fun testFileNotFound() {
  val plugin = NativeFilePreviewPlugin()
  // Test with mock file
}
```

--------------------------------

### Get Default Platform Instance

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreviewPlatform.md

Retrieves the default platform implementation instance. Used to access platform-specific file preview methods.

```dart
static NativeFilePreviewPlatform get instance => _instance
```

```dart
// Get the current platform instance
final platform = NativeFilePreviewPlatform.instance;
final version = await platform.getPlatformVersion();
```

--------------------------------

### Future Example Usage

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/types.md

Illustrates different ways to work with Futures, including awaiting completion, handling results with .then(), and combining multiple futures with Future.wait().

```dart
// Await a future
await nativeFilePreview.previewFile(filePath);

// Handle with .then()
nativeFilePreview.previewFile(filePath).then((_) {
  print('Preview completed');
});

// Combine futures
Future.wait([
  nativeFilePreview.previewFile(file1),
  nativeFilePreview.previewFile(file2),
]);
```

--------------------------------

### Android File Paths Configuration

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/README.md

Define accessible file paths for the FileProvider in res/xml/file_paths.xml. This example grants access to files and cache directories.

```xml
<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <files-path name="files" path="."/>
    <cache-path name="cache" path="."/>
</paths>
```

--------------------------------

### NativeFilePreview Class

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/OVERVIEW.md

The main entry point for the Native File Preview plugin. It provides methods to preview files and get the platform version.

```APIDOC
## Class NativeFilePreview

### Description
Provides methods to interact with the native file preview functionality.

### Methods
#### `previewFile(String filePath)`

- **Description**: Opens a native preview for the file specified by the `filePath`.
- **Parameters**:
  - `filePath` (String) - Required - The path to the file to preview.
- **Returns**: `Future<void>`

#### `getPlatformVersion()`

- **Description**: Retrieves the version of the platform (iOS or Android) the plugin is running on.
- **Parameters**: None
- **Returns**: `Future<String?>` - The platform version string, or null if it cannot be determined.
```

--------------------------------

### NativeFilePreviewPlatform Interface

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/Platform-Interface-Pattern.md

The abstract interface defines the contract for platform-specific implementations of native file preview functionality. It includes methods for getting the platform version and previewing files.

```APIDOC
## NativeFilePreviewPlatform

### Description
An abstract interface defining the methods that platform-specific implementations must provide for native file preview functionality.

### Methods

#### `getPlatformVersion()`

- **Description**: Retrieves the version of the native platform.
- **Returns**: A `Future<String?>` representing the platform version.

#### `previewFile(String filePath)`

- **Description**: Initiates the preview of a file at the given file path.
- **Parameters**:
  - `filePath` (String) - Required - The path to the file to be previewed.
- **Returns**: A `Future<void>` indicating the completion of the preview operation.
```

--------------------------------

### Mock Method Channel for Unit Tests

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/configuration.md

Use this setup to mock the method channel for unit testing the plugin's implementation. It allows simulating method calls and their responses.

```dart
import 'package:native_file_preview/native_file_preview_method_channel.dart';
import 'package:flutter_test/flutter_test.dart';

void main() {
  test('Example test setup', () async {
    final implementation = MethodChannelNativeFilePreview();
    
    // Mock the channel
    implementation.methodChannel.setMockMethodCallHandler((call) async {
      if (call.method == 'previewFile') {
        return null; // Simulate success
      }
      return null;
    });
    
    // Use the mock
    await implementation.previewFile('/path/to/file.pdf');
  });
}
```

--------------------------------

### Handle NO_APP_FOUND Error

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/errors.md

Catch and handle the NO_APP_FOUND error on Android when no installed application can open the specified file type. This prompts the user to install a suitable application.

```dart
try {
  await nativeFilePreview.previewFile('/path/to/file.xyz');
} on PlatformException catch (e) {
  if (e.code == 'NO_APP_FOUND') {
    // Handle: No app can open this file type
    // Show user: "No app available to open this file type"
    // Suggest: Install a suitable app from Play Store
  }
}
```

--------------------------------

### Preview File Implementation

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreviewPlugin-Android.md

Handles the 'previewFile' method call. It takes a map of arguments, expecting a 'file' key with the file path, URL, or content URI. It uses the system Intent to open the file for preview.

```kotlin
private fun previewFile(arguments: Map<String, Any>, result: Result) {
    val filePath = arguments["file"] as? String
    if (filePath == null) {
        result.error("INVALID_FILE_PATH", "Missing or null file path", null)
        return
    }

    val activity = activityBinding?.activity
    if (activity == null) {
        result.error("NO_ACTIVITY", "No activity available", null)
        return
    }

    try {
        val uri = Uri.parse(filePath)
        val intent = Intent(Intent.ACTION_VIEW).apply {
            setDataAndType(uri, "*/*")
            addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)
        }

        if (intent.resolveActivity(activity.packageManager) != null) {
            activity.startActivity(intent)
            result.success(null)
        } else {
            result.error("NO_APP_FOUND", "No app can handle this file type", null)
        }
    } catch (e: FileNotFoundException) {
        result.error("FILE_NOT_FOUND", "File does not exist", e.message)
    } catch (e: SecurityException) {
        result.error("CONTENT_URI_INACCESSIBLE", "Content URI cannot be accessed", e.message)
    } catch (e: Exception) {
        result.error("INTENT_ERROR", "Intent creation failed", e.message)
    }
}
```

--------------------------------

### NativeFilePreview Class Definition

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreview.md

Defines the NativeFilePreview class with methods for getting the platform version and previewing files.

```dart
class NativeFilePreview {
  Future<String?> getPlatformVersion()
  Future<void> previewFile(String filePath)
}
```

--------------------------------

### Show File Preview

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFileViewerPreview-iOS.md

Creates and presents a file preview modally. Ensure you have a valid UIViewController and handle the completion callback for dismissal.

```swift
let fileURL = URL(fileURLWithPath: "/path/to/document.pdf")
let preview = NativeFileViewerPreview(file: fileURL)

guard let viewController = UIApplication.shared.topViewController() else {
  return
}

preview.show(viewController: viewController) { result in
  // Called when preview is dismissed
  // result is nil on success
}
```

--------------------------------

### Previewing a File with NativeFilePreview

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/OVERVIEW.md

Demonstrates how to instantiate and use the NativeFilePreview class to preview a file. Ensure the file path is correctly formatted.

```dart
final preview = NativeFilePreview();
await preview.previewFile('/path/to/document.pdf');
```

--------------------------------

### Testing MethodChannel previewFile Arguments

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/MethodChannelNativeFilePreview.md

Demonstrates how to test the `previewFile` method by setting up a mock MethodChannel handler to verify that the correct arguments are passed to the native platform.

```dart
test('previewFile sends correct arguments', () async {
  final implementation = MethodChannelNativeFilePreview();
  
  // Set up a mock method channel response
  implementation.methodChannel.setMockMethodCallHandler((call) async {
    if (call.method == 'previewFile') {
      // Verify arguments
      expect(call.arguments, {'file': '/path/to/file.pdf'});
      return null;
    }
  });
  
  await implementation.previewFile('/path/to/file.pdf');
});
```

--------------------------------

### Get FileProvider URI

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreviewPlugin-Android.md

Use FileProvider.getUriForFile to obtain a content URI for secure file access on Android 7.0+.

```kotlin
val fileProviderUri = FileProvider.getUriForFile(
  activity,
  "${activity.packageName}.fileprovider",
  file
)
```

--------------------------------

### Basic File Preview Usage

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/OVERVIEW.md

Import the library, create an instance of NativeFilePreview, and call the previewFile method with the file path. Handle potential PlatformExceptions.

```dart
// 1. Import
import 'package:native_file_preview/native_file_preview.dart';

// 2. Create instance
final _preview = NativeFilePreview();

// 3. Call previewFile
try {
  await _preview.previewFile('/path/to/file.pdf');
} on PlatformException catch (e) {
  // Handle error
  print('Error: ${e.code} - ${e.message}');
}
```

--------------------------------

### previewController(_:previewItemAt:)

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFileViewerPreview-iOS.md

Implements the `QLPreviewControllerDataSource` protocol to return the preview item at the specified index. This method provides the file URL to be previewed.

```APIDOC
## previewController(_:previewItemAt:)

### Description
Returns the preview item at the specified index. This method is part of the `QLPreviewControllerDataSource` protocol and provides the file to be previewed.

### Signature
```swift
func previewController(_ controller: QLPreviewController, previewItemAt index: Int) -> QLPreviewItem
```

### Parameters
#### Path Parameters
- **controller** (QLPreviewController) - Required - The preview controller requesting the item.
- **index** (Int) - Required - The index of the item (always 0 since only 1 item).

### Returns
`QLPreviewItem` - The file URL cast as a `QLPreviewItem`. `URL` conforms to the `QLPreviewItem` protocol.

### Details
- Returns `self.file` cast as `QLPreviewItem`.
- `URL` naturally conforms to `QLPreviewItem` protocol because it can provide a preview representation.
- Index parameter is ignored; always returns the single file.

### Implementation
```swift
return file as QLPreviewItem
```
```

--------------------------------

### NativeFileViewerPreview Constructor

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFileViewerPreview-iOS.md

Initializes a new NativeFileViewerPreview instance with a specific file URL. This manager is responsible for providing the file to the QuickLook preview controller.

```APIDOC
## init(file:)

### Description
Creates a new preview manager for the specified file. This manager will provide the file to the QuickLook preview controller.

### Signature
```swift
init(file: URL)
```

### Parameters
#### Path Parameters
- **file** (URL) - Required - The file URL to preview. Can be a local file URL or remote HTTP(S) URL.

### Details
- Stores the file URL for later use by the preview controller.
- The file must be a valid, readable URL by the time `show(viewController:promise:)` is called.

### Example
```swift
let fileURL = URL(fileURLWithPath: "/path/to/document.pdf")
let preview = NativeFileViewerPreview(file: fileURL)
```
```

--------------------------------

### show(viewController:promise:)

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFileViewerPreview-iOS.md

Creates and presents the preview controller modally. This method is used to initiate the file preview display.

```APIDOC
## show(viewController:promise:)

### Description
Creates and presents the preview controller modally. This method is used to initiate the file preview display.

### Method
Swift

### Parameters
#### Path Parameters
- **viewController** (UIViewController) - Yes - The view controller to present the preview from.
- **promise** (FlutterResult) - Yes - The Flutter completion callback. Called with `nil` when preview is dismissed.

### Details
**Process:**
1. Creates a new `NativeFileViewerPreviewViewController`
2. Sets `self` as the data source for the preview controller
3. Calls `presentModal(viewController:promise:)` to present the preview

**Lifecycle:**
- The preview controller is presented as a modal
- When the user dismisses the preview, the promise is called with `nil`
- After dismissal, the preview controller is automatically released

### Example
```swift
let fileURL = URL(fileURLWithPath: "/path/to/document.pdf")
let preview = NativeFileViewerPreview(file: fileURL)

guard let viewController = UIApplication.shared.topViewController() else {
  return
}

preview.show(viewController: viewController) { result in
  // Called when preview is dismissed
  // result is nil on success
}
```
```

--------------------------------

### Initialize NativeFileViewerPreview

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFileViewerPreview-iOS.md

Creates a new preview manager for a specified file. The file must be a valid, readable URL by the time `show(viewController:promise:)` is called.

```swift
let fileURL = URL(fileURLWithPath: "/path/to/document.pdf")
let preview = NativeFileViewerPreview(file: fileURL)
```

--------------------------------

### MethodChannelNativeFilePreview

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/Platform-Interface-Pattern.md

The default implementation of the NativeFilePreviewPlatform using MethodChannels to communicate with native code. It exposes methods to get the platform version and preview files.

```APIDOC
## MethodChannelNativeFilePreview

### Description
Provides the default implementation for interacting with native file preview features via MethodChannels. This class allows developers to retrieve the platform's version information and trigger file previews.

### Methods

#### `getPlatformVersion()`

##### Description
Asynchronously retrieves the version of the platform.

##### Returns
- `Future<String?>`: A future that completes with the platform version string, or null if the version cannot be retrieved.

##### Example
```dart
final version = await MethodChannelNativeFilePreview().getPlatformVersion();
print('Platform version: $version');
```

#### `previewFile(String filePath)`

##### Description
Asynchronously triggers the preview of a specified file.

##### Parameters
- **filePath** (String) - Required - The absolute path to the file that needs to be previewed.

##### Returns
- `Future<void>`: A future that completes when the file preview operation has been initiated.

##### Example
```dart
await MethodChannelNativeFilePreview().previewFile('/path/to/your/document.pdf');
```
```

--------------------------------

### previewFile Method

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreviewPlatform.md

Launches a native file preview for a given file path. This is an abstract method that must be implemented by platform-specific subclasses.

```APIDOC
## Abstract Methods

### previewFile

Launches a native file preview for the specified file.

#### Signature

```dart
Future<void> previewFile(String filePath)
```

#### Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| filePath | String | Yes | Path to the file to preview. |

#### Returns

`Future<void>` — A future that completes when the preview action is complete.

#### Throws

`UnimplementedError` if not overridden by a platform-specific subclass.

#### Implementation Notes

Platform implementations should handle:
- File existence validation
- File readability checks
- Platform-specific path format conversion
- Native UI presentation
- Error reporting with specific error codes
```

--------------------------------

### Implement onAttachedToActivity

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreviewPlugin-Android.md

Implement this method to get access to the ActivityPluginBinding when an activity is available. This binding is crucial for accessing the application context and launching intents.

```kotlin
override fun onAttachedToActivity(binding: ActivityPluginBinding) {
    activityBinding = binding
}
```

--------------------------------

### Preview File Implementation (Kotlin)

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreviewPlugin-Android.md

Handles the core logic for previewing a file, including URI resolution, MIME type determination, and launching an intent. It supports content://, file://, and absolute paths, granting necessary read permissions.

```kotlin
private fun previewFile(filePath: String, result: Result)
```

--------------------------------

### Basic File Preview in Flutter

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/README.md

Demonstrates how to use the NativeFilePreview plugin to preview a file given its path. Includes basic error handling for PlatformExceptions.

```dart
import 'package:native_file_preview/native_file_preview.dart';

class FilePreviewExample extends StatelessWidget {
  final _nativeFilePreview = NativeFilePreview();

  Future<void> _previewFile(String filePath) async {
    try {
      await _nativeFilePreview.previewFile(filePath);
    } on PlatformException catch (e) {
      print('Error previewing file: ${e.message}');
      // Handle error (show dialog, snackbar, etc.)
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('File Preview Demo')),
      body: Center(
        child: ElevatedButton(
          onPressed: () => _previewFile('/path/to/your/file.pdf'),
          child: Text('Preview File'),
        ),
      ),
    );
  }
}
```

--------------------------------

### previewFile

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/OVERVIEW.md

Presents a file preview using the native platform's capabilities. On iOS, it displays a QuickLook modal. On Android, it launches an Intent to open the file.

```APIDOC
## previewFile

### Description
Presents a file preview using the native platform's capabilities. On iOS, it displays a QuickLook modal. On Android, it launches an Intent to open the file.

### Method Channel
`native_file_preview`

### Arguments
`Map<String, String>`
- **file** (String) — Path to file

### Return
`null` on success

### Errors
Platform-specific error codes (e.g., FILE_NOT_FOUND, NO_APP_FOUND)
```

--------------------------------

### Get Platform Version Abstract Method

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreviewPlatform.md

Abstract method to be implemented by subclasses to retrieve the platform version string. Returns a future that may resolve to null.

```dart
Future<String?> getPlatformVersion()
```

--------------------------------

### Singleton Instance Management

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/Platform-Interface-Pattern.md

Explains how to manage the singleton instance of the NativeFilePreviewPlatform, allowing for default and custom implementations.

```APIDOC
## Singleton Instance Management

### Description
Manages a single instance of the `NativeFilePreviewPlatform`. A default instance (`MethodChannelNativeFilePreview`) is provided, and it can be replaced with custom implementations.

### Accessing the Instance

- **Getter**: `static NativeFilePreviewPlatform get instance => _instance;`
  - Retrieves the current singleton instance.

### Setting the Instance

- **Setter**: `static set instance(NativeFilePreviewPlatform instance)`
  - Replaces the current singleton instance with a new one.
  - Verifies the provided instance using the internal token before assignment.
  - Example Usage:
    ```dart
    NativeFilePreviewPlatform.instance = MyCustomFilePreview();
    ```
```

--------------------------------

### Return FlutterError for File Not Found in Swift

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/types.md

Example of returning a `FlutterError` to the Dart layer when a file is not found. This includes a specific error code, message, and optional details.

```swift
result(FlutterError(code: "FILE_NOT_FOUND", message: "File does not exist", details: nil))
```

--------------------------------

### Create a Mock Native File Preview Implementation

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/Platform-Interface-Pattern.md

Implement a mock version of the NativeFilePreviewPlatform for testing purposes. Set this mock as the active instance to intercept calls.

```dart
class MockNativeFilePreview extends NativeFilePreviewPlatform {
  @override
  Future<String?> getPlatformVersion() async => 'test-version';

  @override
  Future<void> previewFile(String filePath) async {
    // Custom behavior
    print('Mock preview: $filePath');
  }
}

// Set as active implementation
NativeFilePreviewPlatform.instance = MockNativeFilePreview();

// Now NativeFilePreview uses the mock
final preview = NativeFilePreview();
await preview.previewFile('/path/to/file.pdf'); // Uses mock implementation
```

--------------------------------

### Get File Extension for MIME Type

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/types.md

Determine the MIME type of a file based on its extension. This function maps common file extensions to their corresponding MIME types.

```kotlin
private fun getMimeTypeFromFile(file: File): String? {
  val extension = file.extension.lowercase()
  return when (extension) {
    "pdf" -> "application/pdf"
    else -> null
  }
}
```

--------------------------------

### Get Platform Version using MethodChannelNativeFilePreview

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/MethodChannelNativeFilePreview.md

Retrieve the platform version string from the native code. This method returns a Future that resolves to the version string or null if unavailable.

```dart
final implementation = MethodChannelNativeFilePreview();
final version = await implementation.getPlatformVersion();
print('Platform version: $version');
```

--------------------------------

### Mocking MethodChannelNativeFilePreview for Testing

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/MethodChannelNativeFilePreview.md

Demonstrates how to mock the MethodChannelNativeFilePreview to test its methods, specifically previewFile and getPlatformVersion. This is useful for unit testing platform channel interactions without needing a real device or emulator.

```dart
import 'package:flutter_test/flutter_test.dart';
import 'package:native_file_preview/native_file_preview_method_channel.dart';

void main() {
  test('MethodChannelNativeFilePreview.previewFile', () async {
    final implementation = MethodChannelNativeFilePreview();
    
    // Mock the method channel
    implementation.methodChannel.setMockMethodCallHandler((call) async {
      if (call.method == 'previewFile') {
        return null;
      }
      return null;
    });
    
    // Should not throw
    await implementation.previewFile('/path/to/file.pdf');
  });

  test('MethodChannelNativeFilePreview.getPlatformVersion', () async {
    final implementation = MethodChannelNativeFilePreview();
    
    implementation.methodChannel.setMockMethodCallHandler((call) async {
      if (call.method == 'getPlatformVersion') {
        return '1.0.0';
      }
      return null;
    });
    
    final version = await implementation.getPlatformVersion();
    expect(version, '1.0.0');
  });
}
```

--------------------------------

### Preview a File with NativeFilePreview

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/example/README.md

Instantiate NativeFilePreview and call the previewFile method with the desired file path. Ensure the file exists and is accessible.

```dart
final nativeFilePreview = NativeFilePreview();
await nativeFilePreview.previewFile('/path/to/file.txt');
```

--------------------------------

### previewFile

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/MethodChannelNativeFilePreview.md

Sends a request to the native platform to preview a file. This method takes a file path as input and initiates the native file preview mechanism.

```APIDOC
## previewFile

### Description
Sends a request to the native platform to preview a file. Supports absolute paths, file:// URLs, and content:// URIs.

### Method
MethodChannel

### Endpoint
previewFile

### Parameters
#### Arguments
- **filePath** (String) - Yes - Path to the file to preview. Supports absolute paths, file:// URLs, and content:// URIs.

### Method Channel Details
- **Method name:** `'previewFile'`
- **Arguments:** `{'file': filePath}` (Map<String, String>)
- **Return type:** `void` (returns null)

### Error Handling
Platform exceptions are raised with error codes defined by the native implementation:

| Error Code |
|------------| 
| `INVALID_ARGUMENTS` |
| `FILE_NOT_FOUND` |
| `FILE_NOT_READABLE` |
| `NO_VIEW_CONTROLLER` |
| `NO_ACTIVITY` |
| `NO_APP_FOUND` |
| `CONTENT_URI_INACCESSIBLE` |

### Example
```dart
import 'package:native_file_preview/native_file_preview_method_channel.dart';

final channel = MethodChannelNativeFilePreview();

try {
  await channel.previewFile('/path/to/document.pdf');
} on PlatformException catch (e) {
  print('Error: ${e.code} - ${e.message}');
}
```
```

--------------------------------

### previewFile

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreviewPlugin-iOS.md

Opens a file preview for the specified file. It takes a map containing the file path as an argument and returns nil on success. Errors can occur if arguments are invalid, the file URL is invalid, the file is not found or readable, or if no view controller is available.

```APIDOC
## previewFile

### Description
Opens a file preview for the specified file. This method is used to display the content of a file to the user.

### Method
`previewFile`

### Arguments
- `file` (String) - Required - The path to the file to be previewed.

### Return
`nil` on success.

### Errors
- `INVALID_ARGUMENTS`: Indicates that the provided arguments are not valid.
- `INVALID_FILE_URL`: Indicates that the file URL is invalid.
- `FILE_NOT_FOUND`: Indicates that the specified file could not be found.
- `FILE_NOT_READABLE`: Indicates that the file is not readable.
- `NO_VIEW_CONTROLLER`: Indicates that no view controller is available to display the preview.
```

--------------------------------

### previewFile

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/README.md

Opens the specified file using the platform's native preview functionality. This method handles the underlying platform-specific implementations for displaying file previews.

```APIDOC
## previewFile(String filePath)

### Description
Opens the specified file using the platform's native preview functionality.

### Method
`previewFile`

### Parameters
#### Path Parameters
- **filePath** (String) - Required - Path to the file to preview. Supports local paths, file:// URLs, and content:// URIs.

### Returns
`Future<void>`

### Throws
`PlatformException` with specific error codes for different failure scenarios.
```

--------------------------------

### Return Single Preview Item

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFileViewerPreview-iOS.md

Returns the single file URL as a QLPreviewItem. The index parameter is ignored as this class only handles one file.

```swift
return file as QLPreviewItem
```

--------------------------------

### Preview File Abstract Method

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreviewPlatform.md

Abstract method that must be implemented by subclasses to launch a native file preview. Requires the file path as input.

```dart
Future<void> previewFile(String filePath)
```

--------------------------------

### Configure File Paths in res/xml/file_paths.xml

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/configuration.md

Define accessible directories for FileProvider by creating this XML file. Use elements like <files-path>, <cache-path>, etc., to specify access scopes.

```xml
<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <!-- Allow access to app's files directory -->
    <files-path name="files" path="." />
    
    <!-- Allow access to app's cache directory -->
    <cache-path name="cache" path="." />
    
    <!-- Optional: Allow access to external storage -->
    <!-- <external-path name="external" path="." /> -->
    
    <!-- Optional: Allow access to specific external directory -->
    <!-- <external-files-path name="external_files" path="." /> -->
    
    <!-- Optional: Allow access to external cache directory -->
    <!-- <external-cache-path name="external_cache" path="." /> -->
</paths>
```

--------------------------------

### presentModal

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFileViewerPreviewViewController-iOS.md

Presents the preview controller modally and stores the completion callback. This method is used to display the file preview to the user and ensures that a callback is triggered upon dismissal.

```APIDOC
## presentModal(viewController:promise:)

### Description
Presents the preview controller modally and stores the completion callback. This method is used to display the file preview to the user and ensures that a callback is triggered upon dismissal.

### Method
Swift

### Parameters
#### Path Parameters
- **viewController** (UIViewController) - Required - The view controller from which to present the preview.
- **promise** (FlutterResult) - Required - The callback to invoke when preview is dismissed.

### Request Example
```swift
let previewController = NativeFileViewerPreviewViewController()
previewController.dataSource = someDataSource

previewController.presentModal(viewController: self) { result in
  print("Preview dismissed")
  // result is nil
}
```

### Details
1. Stores the `promise` callback in the instance variable.
2. Calls `viewController.present(self, animated: true)` to present the preview controller modally.
3. The presentation is animated (slides up from bottom on iOS).

**Timing:**
- `promise` is stored before presentation.
- Presentation occurs with animation.
- User can interact with the preview.
- When user dismisses preview, `viewWillDisappear` is called.
- `promise` callback is invoked with `nil`.
```

--------------------------------

### Complete Error Handling Pattern for File Preview

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/errors.md

This pattern demonstrates comprehensive error handling for the `previewFile` method. It catches `PlatformException` to manage specific file-related errors and includes a general catch block for unexpected issues. Use this to provide user-friendly feedback for various failure scenarios.

```dart
import 'package:flutter/services.dart';

Future<void> previewFileWithErrorHandling(String filePath) async {
  try {
    await nativeFilePreview.previewFile(filePath);
  } on PlatformException catch (e) {
    switch (e.code) {
      case 'FILE_NOT_FOUND':
        _showError('File not found', 'The file does not exist');
        break;
      case 'FILE_NOT_READABLE':
        _showError('Permission denied', 'Cannot access this file');
        break;
      case 'NO_APP_FOUND':
        _showError('No app available', 'Install an app to view this file type');
        break;
      case 'NO_VIEW_CONTROLLER':
      case 'NO_ACTIVITY':
        _showError('Try again', 'The app is not ready. Please try again.');
        break;
      case 'CONTENT_URI_INACCESSIBLE':
        _showError('Invalid file', 'Cannot access this file');
        break;
      default:
        _showError('Preview failed', e.message ?? 'Unknown error');
    }
  } catch (e) {
    _showError('Unexpected error', e.toString());
  }
}

void _showError(String title, String message) {
  // Show error to user (dialog, snackbar, etc.)
}
```

--------------------------------

### Singleton Instance Management for Platform Interface

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/Platform-Interface-Pattern.md

Details how to manage a singleton instance of the platform interface, including its default implementation and how to set a custom one.

```dart
static NativeFilePreviewPlatform _instance = MethodChannelNativeFilePreview();

static NativeFilePreviewPlatform get instance => _instance;
static set instance(NativeFilePreviewPlatform instance) {
  PlatformInterface.verifyToken(instance, _token);
  _instance = instance;
}
```

--------------------------------

### Preview a File

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/README.md

Instantiate the NativeFilePreview class and call the previewFile method with the absolute path to the file you want to preview. Ensure the file path is correctly formatted.

```dart
import 'package:native_file_preview/native_file_preview.dart';

final preview = NativeFilePreview();
await preview.previewFile('/path/to/file.pdf');
```

--------------------------------

### NativeFilePreviewPlatform Instance

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreviewPlatform.md

Access and set the default or custom platform implementation for native file preview.

```APIDOC
## Static Members

### instance (getter)

Retrieves the default platform implementation instance.

#### Signature

```dart
static NativeFilePreviewPlatform get instance => _instance
```

#### Returns

`NativeFilePreviewPlatform` — The current platform implementation, which defaults to `MethodChannelNativeFilePreview`.

#### Example

```dart
// Get the current platform instance
final platform = NativeFilePreviewPlatform.instance;
final version = await platform.getPlatformVersion();
```

---

### instance (setter)

Replaces the default platform implementation with a custom one.

#### Signature

```dart
static set instance(NativeFilePreviewPlatform instance)
```

#### Parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| instance | NativeFilePreviewPlatform | Yes | A subclass implementing the platform interface. Must pass token verification. |

#### Throws

`AssertionError` if the instance does not have the correct token, indicating an unauthorized implementation.

#### Example

```dart
// Replace with a mock implementation for testing
class MockNativeFilePreview extends NativeFilePreviewPlatform {
  @override
  Future<String?> getPlatformVersion() async => '1.0.0';

  @override
  Future<void> previewFile(String filePath) async {}
}

// Set the mock as the active instance
NativeFilePreviewPlatform.instance = MockNativeFilePreview();
```
```

--------------------------------

### Initialize NativeFileViewerPreview with URL in Swift

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/types.md

Demonstrates initializing the `NativeFileViewerPreview` class with a `URL` object. This class is designed to hold a file URL for previewing.

```swift
class NativeFileViewerPreview {
  private let file: URL
  
  init(file: URL) {
    self.file = file
  }
}
```

--------------------------------

### Preview Local File using path_provider

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/README.md

Preview a local file by obtaining its path using the `path_provider` package. This is useful for accessing app-specific directories.

```dart
// Using path_provider
final directory = await getApplicationDocumentsDirectory();
await nativeFilePreview.previewFile('${directory.path}/my_file.txt');
```

--------------------------------

### previewFile

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/NativeFilePreview.md

Opens the specified file using the platform's native preview functionality. This method supports various file path formats including absolute paths, file:// URLs, and content:// URIs on Android.

```APIDOC
## previewFile

### Description
Opens the specified file using the platform's native preview functionality. Supports absolute paths, `file://` URLs, and `content://` URIs (Android).

### Method
`Future<void> previewFile(String filePath)`

### Parameters
#### Path Parameters
- **filePath** (String) - Required - Path to the file to preview. Supports absolute paths, `file://` URLs, and `content://` URIs (Android).

### Returns
`Future<void>` — Completes when the file preview is launched. The future completes with null on success when the preview controller is dismissed (iOS) or the intent is handled (Android).

### Error Handling
Throws `PlatformException` with one of the following error codes:

| Error Code |
|---| 
| `INVALID_ARGUMENTS` |
| `FILE_NOT_FOUND` |
| `FILE_NOT_READABLE` |
| `INVALID_FILE_URL` |
| `NO_VIEW_CONTROLLER` |
| `NO_ACTIVITY` |
| `NO_APP_FOUND` |
| `CONTENT_URI_INACCESSIBLE` |

### Example
```dart
import 'package:native_file_preview/native_file_preview.dart';

class FilePreviewScreen extends StatefulWidget {
  @override
  _FilePreviewScreenState createState() => _FilePreviewScreenState();
}

class _FilePreviewScreenState extends State<FilePreviewScreen> {
  final _nativeFilePreview = NativeFilePreview();

  void _previewFile() async {
    try {
      // Preview a local file
      await _nativeFilePreview.previewFile('/path/to/document.pdf');
    } on PlatformException catch (e) {
      _showErrorDialog('Preview Error', e.code, e.message);
    }
  }

  void _showErrorDialog(String title, String code, String? message) {
    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: Text(title),
        content: Text('Error: $code\n${message ?? "Unknown error"}'),
        actions: [
          TextButton(
            onPressed: () => Navigator.pop(context),
            child: Text('OK'),
          ),
        ],
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return ElevatedButton(
      onPressed: _previewFile,
      child: Text('Preview PDF'),
    );
  }
}
```

### Platform-Specific Behavior
**iOS:** Uses the QuickLook framework to display a native preview controller. The preview controller is presented modally and can be dismissed by the user. When dismissed, the future completes.

**Android:** Uses the Intent system with `ACTION_VIEW` to launch an app capable of viewing the file. The method returns immediately after the intent is issued, without waiting for the app to be dismissed.

### File Path Format Support
The method accepts multiple file path formats:

- **Absolute paths:** `/storage/emulated/0/Download/document.pdf`
- **File URLs:** `file:///storage/emulated/0/Download/image.jpg`
- **Content URIs (Android only):** `content://com.android.providers.downloads.documents/document/123`
```

--------------------------------

### Flutter Build Commands

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/configuration.md

Standard Flutter commands for building the application for different platforms. No special configuration is needed for the plugin itself.

```bash
flutter build ios
```

```bash
flutter build apk
```

```bash
flutter build appbundle
```

--------------------------------

### Handle previewFile Method Call on iOS

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/Platform-Interface-Pattern.md

Implement the method channel handler for the 'previewFile' method on iOS. This code processes the file path argument and can return success or an error.

```swift
// NativeFilePreviewPlugin.swift
class NativeFilePreviewPlugin: NSObject, FlutterPlugin {
  func handle(_ call: FlutterMethodCall, result: @escaping FlutterResult) {
    switch call.method {
    case "previewFile":
      // Handle preview request
      let filePath = call.arguments as? String
      // ... implementation
      result(nil)  // or result(FlutterError(...))
    default:
      result(FlutterMethodNotImplemented)
    }
  }
}
```

--------------------------------

### Handle previewFile Method Call on Android

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/api-reference/Platform-Interface-Pattern.md

Implement the method channel handler for the 'previewFile' method on Android. This code extracts the file path from the arguments and can return success or an error.

```kotlin
// NativeFilePreviewPlugin.kt
class NativeFilePreviewPlugin: FlutterPlugin, MethodCallHandler {
  override fun onMethodCall(call: MethodCall, result: Result) {
    when (call.method) {
      "previewFile" -> {
        val filePath = (call.arguments as? Map<*, *>)?.get("file") as? String
        // ... implementation
        result.success(null)  // or result.error(...)
      }
      else -> result.notImplemented()
    }
  }
}
```

--------------------------------

### Import NativeFilePreview API

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/OVERVIEW.md

Import the main NativeFilePreview API class from the package. This is the primary entry point for using the library's functionality.

```dart
import 'package:native_file_preview/native_file_preview.dart';
```

--------------------------------

### Check File Existence

Source: https://github.com/johnny-bytes/native_file_preview/blob/main/_autodocs/types.md

Instantiate a File object with a file path and use the exists() method to check if the file is present on the filesystem. Return an error if the file does not exist.

```kotlin
class File(pathname: String) {
  fun exists(): Boolean
  val extension: String
  val path: String
}
```

```kotlin
val file = File(filePath)
if (!file.exists()) {
  result.error("FILE_NOT_FOUND", "File does not exist: $filePath", null)
  return
}
```