android widget使用

在 \res\xml下建立example_appwidget_info.xml

在layout下建立process_widget.xml,用來顯示widget的布局

建立一個類ProcessWidget繼承AppWidgetProvider

import cn.itcast.mobilesafe.service.UpdateWidgetService;import android.appwidget.AppWidgetProvider;import android.content.Context;import android.content.Intent;import android.sax.StartElementListener;public class ProcessWidget extends AppWidgetProvider {Intent intent;@Overridepublic void onDeleted(Context context, int[] appWidgetIds) {super.onDeleted(context, appWidgetIds);intent = new Intent(context,UpdateWidgetService.class);context.stopService(intent);}@Overridepublic void onEnabled(Context context) {super.onEnabled(context);intent = new Intent(context,UpdateWidgetService.class);context.startService(intent);}}

建立類UpdateWidgetService實現widget更新

import android.app.PendingIntent;import android.app.Service;import android.appwidget.AppWidgetManager;import android.content.ComponentName;import android.content.Intent;import android.graphics.Color;import android.os.IBinder;import android.widget.RemoteViews;public class UpdateWidgetService extends Service {private Timer timer ;private TimerTask task;private AppWidgetManager  widgetmanager;@Overridepublic IBinder onBind(Intent intent) {// TODO Auto-generated method stubreturn null;}@Overridepublic void onCreate() {timer = new Timer();widgetmanager =  AppWidgetManager.getInstance(getApplicationContext());task = new TimerTask() {@Overridepublic void run() {// 更新widget的介面ComponentName name = new ComponentName("cn.itcast.mobilesafe", "cn.itcast.mobilesafe.receiver.ProcessWidget");RemoteViews views = new RemoteViews("cn.itcast.mobilesafe", R.layout.process_widget);views.setTextViewText(R.id.process_count, "進程數目"+TaskUtil.getProcessCount(getApplicationContext()));views.setTextColor(R.id.process_count, Color.RED);views.setTextViewText(R.id.process_memory, "可用記憶體"+TaskUtil.getMemeorySize(getApplicationContext()));views.setTextColor(R.id.process_memory, Color.RED);Intent intent = new Intent(UpdateWidgetService.this,LockScreenReceiver.class);PendingIntent pendingIntent = PendingIntent.getBroadcast(getApplicationContext(), 0, intent, 0);views.setOnClickPendingIntent(R.id.btn_clear, pendingIntent);widgetmanager.updateAppWidget(name, views);}};timer.scheduleAtFixedRate(task, 1000, 2000);super.onCreate();}@Overridepublic void onDestroy() {timer.cancel();timer = null;task =null;super.onDestroy();}}

TaskUtil的代碼如下：

import java.util.List;import android.app.ActivityManager;import android.app.ActivityManager.MemoryInfo;import android.app.ActivityManager.RunningAppProcessInfo;import android.content.Context;import android.text.TextUtils;public class TaskUtil {public static void killAllProcess(Context context) {ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);List runningapps = am.getRunningAppProcesses();for (RunningAppProcessInfo info : runningapps) {String packname = info.processName;am.killBackgroundProcesses(packname);}}public static int getProcessCount(Context context) {ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);List runningapps = am.getRunningAppProcesses();return runningapps.size();}public static String getMemeorySize(Context context) {ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);MemoryInfo outInfo = new ActivityManager.MemoryInfo();am.getMemoryInfo(outInfo);return TextFormater.getDataSize( outInfo.availMem);}}

在AndroidManifest.xml的配置