### FormOptions.setReadonly Example

Source: https://github.com/google/libaddressinput/blob/master/_autodocs/java-enums.md

Example of using setReadonly.

```java
FormOptions options = new FormOptions()
    .setReadonly(AddressField.COUNTRY);  // Country already determined
```

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

### Complete MainActivity Example

Source: https://github.com/google/libaddressinput/blob/master/android/README.md

A full example of MainActivity integrating the AddressWidget.

```java
package com.example.google.widgetdemo;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.ViewGroup;

import com.android.i18n.addressinput.AddressWidget;
import com.google.i18n.addressinput.common.FormOptions;
import com.google.i18n.addressinput.common.ClientCacheManager;
import com.google.i18n.addressinput.common.SimpleClientCacheManager;

public class MainActivity extends AppCompatActivity {
    private AddressWidget addressWidget;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        ViewGroup viewGroup = (ViewGroup) findViewById(R.id.addresswidget);
        FormOptions defaultFormOptions = new FormOptions();
        ClientCacheManager cacheManager = new SimpleClientCacheManager();
        this.addressWidget = new AddressWidget(this, viewGroup, defaultFormOptions, cacheManager);
    }
}
```

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

### AddressProblemType Example

Source: https://github.com/google/libaddressinput/blob/master/_autodocs/java-enums.md

Example of using AddressProblemType.

```java
AddressProblemType problem = AddressProblemType.MISSING_REQUIRED_FIELD;
String id = problem.keyname();  // "missing_required_field"
```

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

### Using Custom Storage Example

Source: https://github.com/google/libaddressinput/blob/master/_autodocs/cpp-data-sources.md

Example of how to use a custom storage implementation with PreloadSupplier and AddressValidator.

```cpp
#include <libaddressinput/preload_supplier.h>
#include <libaddressinput/address_validator.h>

int main() {
    // Create custom storage
    auto storage = new FileStorage("/tmp/address_cache");
    
    // Create source (implementation dependent)
    auto source = new SomeSource();
    
    // Create supplier with custom storage
    auto supplier = std::unique_ptr<i18n::addressinput::Supplier>(
        new i18n::addressinput::PreloadSupplier(source, storage)
    );
    
    // Create validator
    auto validator = std::make_unique<i18n::addressinput::AddressValidator>(
        supplier.get()
    );
    
    // Use validator
    // ...
    
    return 0;
}

```