AppWidgetHost sample

package phs.learning.widgets;

import java.util.ArrayList;

import phs.learning.R;
import android.app.Activity;
import android.appwidget.AppWidgetHost;
import android.appwidget.AppWidgetHostView;
import android.appwidget.AppWidgetManager;
import android.appwidget.AppWidgetProviderInfo;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnLongClickListener;
import android.widget.Button;
import android.widget.LinearLayout;
import android.widget.Toast;

public class Exp_WidgetHost extends Activity {

    private static final int REQUEST_PICK_APPWIDGET = 128;
    private static final int REQUEST_CREATE_APPWIDGET = 129;
    private AppWidgetManager mAppWidgetManager;
    private AppWidgetHost mAppWidgetHost;
    private LinearLayout rootLayout;
    private Button btPick;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        mAppWidgetManager = AppWidgetManager.getInstance(this);
        mAppWidgetHost = new AppWidgetHost(this, R.layout.example_widgethost);

        setContentView(R.layout.example_widgethost);
        rootLayout = (LinearLayout) findViewById(R.id.root_layout);
        btPick = (Button) findViewById(R.id.bt_pick);
        btPick.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                selectWidget();
            }
        });
    }

    @Override
    protected void onStart() {
        super.onStart();
        mAppWidgetHost.startListening();
    }

    @Override
    protected void onStop() {
        mAppWidgetHost.stopListening();
        super.onStop();
    }

    private void selectWidget() {
        int appWidgetId = this.mAppWidgetHost.allocateAppWidgetId();
        Intent pickIntent = new Intent(AppWidgetManager.ACTION_APPWIDGET_PICK);
        pickIntent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, appWidgetId);
        addEmptyData(pickIntent);
        startActivityForResult(pickIntent, REQUEST_PICK_APPWIDGET);

    }

    @SuppressWarnings({ "rawtypes", "unchecked" })
    private void addEmptyData(Intent pickIntent) {
        ArrayList customInfo = new ArrayList();
        pickIntent.putParcelableArrayListExtra(AppWidgetManager.EXTRA_CUSTOM_INFO, customInfo);
        ArrayList customExtras = new ArrayList();
        pickIntent.putParcelableArrayListExtra(AppWidgetManager.EXTRA_CUSTOM_EXTRAS, customExtras);
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if ( resultCode == RESULT_OK ) {
            if ( requestCode == REQUEST_PICK_APPWIDGET ) {
                configureWidget(data);
            } else if ( requestCode == REQUEST_CREATE_APPWIDGET ) {
                createAppWidget(data);
            }
        } else if ( resultCode == RESULT_CANCELED && data != null ) {
            int appWidgetId = data.getIntExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, AppWidgetManager.INVALID_APPWIDGET_ID);
            if ( appWidgetId != AppWidgetManager.INVALID_APPWIDGET_ID ) {
                mAppWidgetHost.deleteAppWidgetId(appWidgetId); //cool ! this is not google fault, this is the fault of the host !
            }
        }
    }

    private void configureWidget(Intent data) {
        Bundle extras = data.getExtras();
        int appWidgetId = extras.getInt(AppWidgetManager.EXTRA_APPWIDGET_ID, AppWidgetManager.INVALID_APPWIDGET_ID);
        AppWidgetProviderInfo appWidgetInfo = mAppWidgetManager.getAppWidgetInfo(appWidgetId);
        if ( appWidgetInfo.configure != null ) {
            Intent intent = new Intent(AppWidgetManager.ACTION_APPWIDGET_CONFIGURE);
            intent.setComponent(appWidgetInfo.configure);
            intent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, appWidgetId);
            startActivityForResult(intent, REQUEST_CREATE_APPWIDGET);
        } else {
            createAppWidget(data);
        }
    }

    private void createAppWidget(Intent data) {
        Bundle extras = data.getExtras();
        final int appWidgetId = extras.getInt(AppWidgetManager.EXTRA_APPWIDGET_ID);
        AppWidgetProviderInfo appWidgetInfo = mAppWidgetManager.getAppWidgetInfo(appWidgetId);
        AppWidgetHostView hostView = mAppWidgetHost.createView(getApplicationContext(), appWidgetId, appWidgetInfo);
        hostView.setAppWidget(appWidgetId, appWidgetInfo);
        LinearLayout.LayoutParams params = createLayoutParams(appWidgetInfo);
        rootLayout.addView(hostView, params);
        hostView.setOnLongClickListener(new OnLongClickListener() {
            @Override
            public boolean onLongClick(View v) {
                Toast.makeText(getApplicationContext(), "Long click " + appWidgetId, Toast.LENGTH_LONG).show();
                return true;
            }
        });
    }

    private android.widget.LinearLayout.LayoutParams createLayoutParams(AppWidgetProviderInfo appWidgetInfo) {
        LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(appWidgetInfo.minWidth, appWidgetInfo.minHeight);
        return params;
    }
}