widget

新建一个类继承AppWidgetProvider重写几个重要的方法，代码如下：

<pre name="code" class="java">package com.example.texttest;

import android.appwidget.AppWidgetManager;
import android.appwidget.AppWidgetProvider;
import android.content.Context;
import android.content.Intent;
import android.util.Log;

public class Widget extends AppWidgetProvider {
	
	@Override
	public void onDeleted(Context context, int[] appWidgetIds) {
		super.onDeleted(context, appWidgetIds);
		context.stopService(new Intent(context, widgetService.class));//停止Service
	}
	
	@Override
	public void onDisabled(Context context) {
		super.onDisabled(context);
		context.stopService(new Intent(context, widgetService.class)); //停止Service
		Log.e("", "最后一个被删除了");
		
	}
	
	@Override
	public void onEnabled(Context context) {
		super.onEnabled(context);
		context.startService(new Intent(context, widgetService.class));//启动Service
		Log.e("", "增加上屏幕");
	}
	
	@Override
	public void onReceive(Context context, Intent intent) {
		super.onReceive(context, intent);
	}
	
	@Override
	public void onUpdate(Context context, AppWidgetManager appWidgetManager,
			int[] appWidgetIds) {
		// TODO Auto-generated method stub
		super.onUpdate(context, appWidgetManager, appWidgetIds);
		Log.e("", "更新");
	}
	

}

写一个widget的布局文件：

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <TextView
        
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="你好 "
        android:id="@+id/widget_tv"
        android:textColor="#ffaaaa"
        android:textSize="30dp" />

</RelativeLayout>

新建一个XML文件夹存放Widget的配制文件：

<?xml version="1.0" encoding="utf-8"?>
<appwidget-provider xmlns:android="http://schemas.android.com/apk/res/android"
    android:initialLayout="@layout/widget"
    android:minHeight="40dp"
    android:minWidth="180dp"
    android:updatePeriodMillis="8000" >
<!--  initialLayout 找到Widget的布局，  minHeight,minWidth 最小宽高 。updatePeriodMillis 更新时间，默认3分钟，小于3分钟默认三分钟-->
    
</appwidget-provider>

在AndroidManifast里注册：

  <service android:name="com.example.texttest.widgetService" >
        </service>

        <receiver android:name="com.example.texttest.Widget" >
            <intent-filter>
                <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
            </intent-filter>

            <meta-data
                android:name="android.appwidget.provider"
                android:resource="@xml/widget_layout" />
        </receiver>

写一个Service

package com.example.texttest;

import java.util.Timer;
import java.util.TimerTask;

import android.app.Service;
import android.appwidget.AppWidgetManager;
import android.content.ComponentName;
import android.content.Intent;
import android.os.IBinder;
import android.widget.RemoteViews;
public class widgetService extends Service {

	private int i = 0;
	private Timer time;

	@Override
	public IBinder onBind(Intent arg0) {

		return null;
	}

	@Override
	public void onCreate() {
		super.onCreate();
		time = new Timer();
		time.schedule(new TimerTask() {

			@Override
			public void run() {
				updateView();
			}
		}, 0, 1000); // 1000是间隔时间，0是延迟
	}

	/**
	 * 更新UI
	 * @param getApplicationContext() 上下文
	 */
	private void updateView() {

		i++;
		RemoteViews re = new RemoteViews(getPackageName(), R.layout.widget);// 找到Widget的布局
		re.setTextViewText(R.id.widget_tv, "你好" + i); // 设置内容
		AppWidgetManager appwm = AppWidgetManager
				.getInstance(getApplicationContext()); // 获得WidgetManager
		ComponentName com = new ComponentName(getApplicationContext(),
				Widget.class); // 设置widget的类
		appwm.updateAppWidget(com, re); //
	}

	@Override
	public void onDestroy() {
		super.onDestroy();
		time = null; //清空time
	}
}