Android开发——桌面插件

来源：互联网发布：java的重载和重写编辑：程序博客网时间：2024/05/01 02:54

开发一个在手机桌面上显示的插件需要3个步骤：

  1. 继承AppWidgetProvider

  2. 编写widget的界面xml, 编写mywidget属性xml

  3. AndroidManifest.xml  注册插件

以自增的数字为例。



1. 继承AppWidgetProvider

public class MyWidgetProvider extends AppWidgetProvider
{
    private static Timer myTimer;
    private static int index = 0;

    private final String broadCastString = "knowheart.wd.appWidgetUpdate";

    @Override
    public void onDeleted(Context context, int[] appWidgetIds)
    {
        // TODO Auto-generated method stub
        super.onDeleted(context, appWidgetIds);

    }



    @Override
    public void onEnabled(Context context)
    {
        // TODO Auto-generated method stub
        super.onEnabled(context);

    }

    @Override
    public void onUpdate(Context context, AppWidgetManager appWidgetManager,
            int[] appWidgetIds)
    {
        // TODO Auto-generated method stub
        super.onUpdate(context, appWidgetManager, appWidgetIds);
    }



    @Override
    public void onReceive(Context context, Intent intent)
    {
        super.onReceive(context, intent);
    }

}

添加一个类继承AppWidgetProvider，控制我们的插件更新删除的操作，相关方法onEnabled、onUpdate、onReceive

2. 编写widget的xml界面, 编写mywidget属性xml

layout/widget_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:background="#000000"
    android:layout_gravity="center_horizontal"
    android:layout_width="300dp"
    android:layout_height="wrap_content">

    <TextView
        android:id="@+id/update"
        android:text="0"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
     />

</LinearLayout>

新建xml文件夹，添加xml文件：xml/mywidget.xml
<?xml version="1.0" encoding="UTF-8"?>
<appwidget-provider xmlns:android="http://schemas.android.com/apk/res/android"
    android:minWidth="300dip" android:minHeight="72dp"
    android:updatePeriodMillis="86400000"
    android:initialLayout="@layout/widget_layout"
    >
</appwidget-provider>
设置了插件的长宽、刷新时间（ 0为手动刷新）和插件的界面xml



  3. AndroidManifest.xml  注册插件

<receiver android:name="MyWidgetProvider" >
            <intent-filter >
                <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
                <action android:name="com.wd.appWidgetUpdate" >
                </action>
            </intent-filter>

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

<action android:name="com.wd.appWidgetUpdate" > 向系统注册一个广播，在逻辑处理时将该广播发送给AppWidgetProvider的更新方法，以实现手动刷新。

至此基本实现预想功能！！！！！

让插件显示的数字/1000ms+1需做后台处理

public class MyWidgetProvider extends AppWidgetProvider
{
    private static Timer myTimer;
    private static int index = 0;

    //定义我们要发送的事件
    private final String broadCastString = "com.wd.appWidgetUpdate";

    @Override
    public void onDeleted(Context context, int[] appWidgetIds)
    {
        // TODO Auto-generated method stub
        super.onDeleted(context, appWidgetIds);

        System.out.println("onDeleted");
    }

    @Override
    public void onEnabled(Context context)
    {
        System.out.println("onEnabled");
        // TODO Auto-generated method stub
        super.onEnabled(context);

        //在插件被创建的时候这里会被调用，所以我们在这里开启一个timer 每秒执行一次
        MyTask mMyTask = new MyTask(context);
        myTimer = new Timer();
        myTimer.schedule(mMyTask, 1000, 1000);
        System.out.println("onEnabled2");
    }



    @Override
    public void onUpdate(Context context, AppWidgetManager appWidgetManager,
            int[] appWidgetIds)
    {
        System.out.println("onUpdate");
        // TODO Auto-generated method stub
        super.onUpdate(context, appWidgetManager, appWidgetIds);
    }



    @Override
    public void onReceive(Context context, Intent intent)
    {
        //当判断到是该事件发过来时，我们就获取插件的界面，然后将index自加后传入到textview中
        System.out.println("onReceive");
        if(intent.getAction().equals(broadCastString))
        {
            index++;

            RemoteViews rv = new RemoteViews(context.getPackageName(), R.layout.widget_layout);
            rv.setTextViewText(R.id.update, Integer.toString(index));

            //将该界面显示到插件中
            AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context);
            ComponentName componentName = new ComponentName(context,MyWidgetProvider.class);
            appWidgetManager.updateAppWidget(componentName, rv);
        }
        // TODO Auto-generated method stub
        super.onReceive(context, intent);
    }



    class MyTask extends TimerTask
    {

        private Context mcontext = null;
        private Intent intent = null;

        public MyTask(Context context) {

            //新建一个要发送的Intent
            mcontext = context;
            intent = new Intent();
            intent.setAction(broadCastString);
        }
        @Override
        public void run()
        {
            System.out.println("2");
            //发送广播(由onReceive来接收)
            mcontext.sendBroadcast(intent);
        }

    }
}