### Initialize File Picker Demo

Source: https://pub.dev/packages/file_picker/example

This is the main entry point for the file picker example application. It initializes the FilePickerDemo widget.

```dart
import 'package:file_picker_example/src/file_picker_demo.dart';
import 'package:flutter/widgets.dart';

void main() => runApp(FilePickerDemo());
```

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

### Pubspec.yaml Dependency

Source: https://pub.dev/packages/file_picker/install

This is an example of how the file_picker dependency will appear in your pubspec.yaml file after running the add command.

```yaml
dependencies:
  file_picker: ^11.0.2
```

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

### Upload File to Firebase Storage (Web)

Source: https://pub.dev/packages/file_picker

Example of picking a file and uploading its bytes to Firebase Storage using Flutter Web. Requires Firebase Storage SDK setup.

```dart
FilePickerResult? result = await FilePicker.pickFiles();

if (result != null) {
  Uint8List fileBytes = result.files.first.bytes;
  String fileName = result.files.first.name;
  
  // Upload file
  await FirebaseStorage.instance.ref('uploads/$fileName').putData(fileBytes);
}
```

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

### Pick Directory Path

Source: https://pub.dev/packages/file_picker

Use this method to allow users to select a directory. Returns null if the user cancels.

```dart
String? selectedDirectory = await FilePicker.getDirectoryPath();

if (selectedDirectory == null) {
  // User canceled the picker
}
```

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

### Load File Details

Source: https://pub.dev/packages/file_picker

Retrieves details of the picked file, including name, bytes, size, extension, and path. The 'bytes' property is useful for immediate data handling.

```dart
FilePickerResult? result = await FilePicker.pickFiles();

if (result != null) {
  PlatformFile file = result.files.first;

  print(file.name);
  print(file.bytes);
  print(file.size);
  print(file.extension);
  print(file.path);
} else {
  // User canceled the picker
}
```

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

### Retrieve Files as XFiles

Source: https://pub.dev/packages/file_picker

Demonstrates how to access picked files as XFile objects, which can be used with other Flutter libraries. Both a list of all XFiles and individual XFiles are accessible.

```dart
FilePickerResult? result = await FilePicker.pickFiles();

if (result != null) {
  // All files
  List<XFile> xFiles = result.xFiles;

  // Individually
  XFile xFile = result.files.first.xFile;
} else {
  // User canceled the picker
}
```

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

### Pick Multiple Files

Source: https://pub.dev/packages/file_picker

Allows users to select multiple files. The result.paths provides a list of selected file paths.

```dart
FilePickerResult? result = await FilePicker.pickFiles(allowMultiple: true);

if (result != null) {
  List<File> files = result.paths.map((path) => File(path!)).toList();
} else {
  // User canceled the picker
}
```

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

### Pick Single File

Source: https://pub.dev/packages/file_picker

Use this to pick a single file. The result can be null if the user cancels the picker.

```dart
FilePickerResult? result = await FilePicker.pickFiles();

if (result != null) {
  File file = File(result.files.single.path!); 
} else {
  // User canceled the picker
}
```

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

### Save File Dialog

Source: https://pub.dev/packages/file_picker

Opens a save-file/save-as dialog, allowing the user to specify the output file name and location. Returns the selected path or null if canceled.

```dart
String? outputFile = await FilePicker.saveFile(
  dialogTitle: 'Please select an output file:',
  fileName: 'output-file.pdf',
);

if (outputFile == null) {
  // User canceled the picker
}
```

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

### Pick Files with Extension Filter

Source: https://pub.dev/packages/file_picker

Enables filtering files by a custom list of extensions. Ensure 'FileType.custom' is set for custom filtering.

```dart
FilePickerResult? result = await FilePicker.pickFiles(
  allowMultiple: true,
  type: FileType.custom,
  allowedExtensions: ['jpg', 'pdf', 'doc'],
);
```

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

### Add file_picker Dependency

Source: https://pub.dev/packages/file_picker/install

Run this command in your terminal to add the file_picker package to your Flutter project. This command automatically updates your pubspec.yaml file.

```bash
flutter pub add file_picker
```

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

### Import file_picker in Dart

Source: https://pub.dev/packages/file_picker/install

Include this import statement at the top of your Dart files to use the functionality provided by the file_picker package.

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

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