Android 手机卫士14--Widget窗口小部件AppWidgetProvider_移动开发_编程开发_程序员俱乐部

1.AndroidManifest.xml根据窗体小部件广播接受者关键字android.appwidget.action.APPWIDGET_UPDATE
　　搜索android:resource="@xml/process_widget_provider"

2.找到xml文件夹下process_widget_provider.xml

class="brush:java;gutter:true;"><appwidget-provider android:minWidth="294.0dip" 
    android:minHeight="72.0dip" 
    android:updatePeriodMillis="0"
    android:initialLayout="@layout/process_widget"
    xmlns:android="http://schemas.android.com/apk/res/android" />

3.initial Layout指向的布局文件process_widget

4.窗体小部件生命周期方法分析

 1 public class MyAppWidgetProvider extends AppWidgetProvider {
 2     private static final String tag = "MyAppWidgetProvider";
 3     @Override
 4     public void onReceive(Context context, Intent intent) {
 5         Log.i(tag, "onReceive............");
 6         super.onReceive(context, intent);
 7     }
 8     @Override
 9     public void onEnabled(Context context) {
10         //创建第一个窗体小部件的方法
11         Log.i(tag, "onEnabled 创建第一个窗体小部件调用方法");
12         //开启服务(onCreate)
13         context.startService(new Intent(context, UpdateWidgetService.class));
14         super.onEnabled(context);
15     }
16     @Override
17     public void onUpdate(Context context, AppWidgetManager appWidgetManager,
18             int[] appWidgetIds) {
19         Log.i(tag, "onUpdate 创建多一个窗体小部件调用方法");
20         //开启服务
21         context.startService(new Intent(context, UpdateWidgetService.class));
22         super.onUpdate(context, appWidgetManager, appWidgetIds);
23     }
24     @Override
25     public void onAppWidgetOptionsChanged(Context context,
26             AppWidgetManager appWidgetManager, int appWidgetId,
27             Bundle newOptions) {
28         //当窗体小部件宽高发生改变的时候调用方法,创建小部件的时候,也调用此方法
29         //开启服务
30         context.startService(new Intent(context, UpdateWidgetService.class));
31         Log.i(tag, "onAppWidgetOptionsChanged 创建多一个窗体小部件调用方法");
32         super.onAppWidgetOptionsChanged(context, appWidgetManager, appWidgetId,
33                 newOptions);
34     }
35     
36     @Override
37     public void onDeleted(Context context, int[] appWidgetIds) {
38         Log.i(tag, "onDeleted 删除一个窗体小部件调用方法");
39         super.onDeleted(context, appWidgetIds);
40     }
41     
42     @Override
43     public void onDisabled(Context context) {
44         Log.i(tag, "onDisabled 删除最后一个窗体小部件调用方法");
45         //关闭服务
46         context.stopService(new Intent(context, UpdateWidgetService.class));
47         super.onDisabled(context);
48     }
49 }

5.窗体小部件的更新进程总数和可用内存大小

    1.将更新过程放置在服务中,服务什么时候开启?服务什么时候关闭?

    2.一旦出现窗体小部件,则需要开启服务,所有窗体小部件销毁的时候,关闭服务

 1 public class UpdateWidgetService extends Service {
 2     protected static final String tag = "UpdateWidgetService";
 3     private Timer mTimer;
 4     private InnerReceiver mInnerReceiver;
 5     @Override
 6     public void onCreate() {
 7         //管理进程总数和可用内存数更新(定时器)
 8         startTimer();
 9         
10         //注册开锁,解锁广播接受者
11         IntentFilter intentFilter = new IntentFilter();
12         //开锁action
13         intentFilter.addAction(Intent.ACTION_SCREEN_ON);
14         //解锁action
15         intentFilter.addAction(Intent.ACTION_SCREEN_OFF);
16         
17         mInnerReceiver = new InnerReceiver();
18         registerReceiver(mInnerReceiver, intentFilter);
19         
20         super.onCreate();
21     }
22     
23     class InnerReceiver extends BroadcastReceiver{
24         @Override
25         public void onReceive(Context context, Intent intent) {
26             if(intent.getAction().equals(Intent.ACTION_SCREEN_ON)){
27                 //开启定时更新任务
28                 startTimer();
29             }else{
30                 //关闭定时更新任务
31                 cancelTimerTask();
32             }
33         }
34     }
35     
36     private void startTimer() {
37         mTimer = new Timer();
38         mTimer.scheduleAtFixedRate(new TimerTask() {
39             @Override
40             public void run() {
41                 //ui定时刷新
42                 updateAppWidget();
43                 Log.i(tag, "5秒一次的定时任务现在正在运行..........");
44             }
45         }, 0, 5000);
46     }
47     public void cancelTimerTask() {
48         //mTimer中cancel方法取消定时任务方法
49         if(mTimer!=null){
50             mTimer.cancel();
51             mTimer = null;
52         }
53     }
54     protected void updateAppWidget() {
55         //1.获取AppWidget对象
56         AppWidgetManager aWM = AppWidgetManager.getInstance(this);
57         //2.获取窗体小部件布局转换成的view对象(定位应用的包名,当前应用中的那块布局文件)
58         RemoteViews remoteViews = new RemoteViews(getPackageName(), R.layout.process_widget);
59         //3.给窗体小部件布view对象,内部控件赋值
60         remoteViews.setTextViewText(R.id.tv_process_count, "进程总数:"+ProcessInfoProvider.getProcessCount(this));
61         //4.显示可用内存大小
62         String strAvailSpace = Formatter.formatFileSize(this, ProcessInfoProvider.getAvailSpace(this));
63         remoteViews.setTextViewText(R.id.tv_process_memory, "可用内存:"+strAvailSpace);
64 
65         
66         //点击窗体小部件,进入应用
67         //1:在那个控件上响应点击事件2:延期的意图
68         Intent intent = new Intent("android.intent.action.HOME");
69         intent.addCategory("android.intent.category.DEFAULT");
70         PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_CANCEL_CURRENT);
71         remoteViews.setOnClickPendingIntent(R.id.ll_root, pendingIntent);
72         
73         //通过延期意图发送广播,在广播接受者中杀死进程,匹配规则看action
74         Intent broadCastintent = new Intent("android.intent.action.KILL_BACKGROUND_PROCESS");
75         PendingIntent broadcast = PendingIntent.getBroadcast(this, 0, broadCastintent, PendingIntent.FLAG_CANCEL_CURRENT);
76         remoteViews.setOnClickPendingIntent(R.id.btn_clear,broadcast);
77         
78         //上下文环境,窗体小部件对应广播接受者的字节码文件
79         ComponentName componentName = new ComponentName(this,MyAppWidgetProvider.class);
80         //更新窗体小部件
81         aWM.updateAppWidget(componentName, remoteViews);
82     }
83     @Override
84     public IBinder onBind(Intent intent) {
85         return null;
86     }
87     @Override
88     public void onDestroy() {
89         if(mInnerReceiver!=null){
90             unregisterReceiver(mInnerReceiver);
91         }
92         //调用onDestroy即关闭服务,关闭服务的方法在移除最后一个窗体小部件的时调用,定时任务也没必要维护
93         cancelTimerTask();
94         super.onDestroy();
95     }
96 }