我正在研究显示剩余电池电量的android小部件。
它似乎在模拟器上工作，除了模拟器的电池电量没有移动，所以我无法进一步测试。在真实设备 (ICS) 上，它只显示初始 textview("TEST") 并且不执行任何其他操作。
显现
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.battery"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<receiver android:name="main.MyBatteryWidget"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
</intent-filter>
<meta-data android:name="android.appwidget.provider"
android:resource="@xml/widget_info" />
</receiver>
<service android:name="main.MyBatteryWidget$BatteryUpdateService"
android:exported="false" >
<intent-filter>
<action android:name="com.example.battery.action.UPDATE" />
</intent-filter>
</service>
</application>
小部件信息.xml
<?xml version="1.0" encoding="utf-8"?>
<appwidget-provider xmlns:android="http://schemas.android.com/apk/res/android"
android:updatePeriodMillis="0"
android:minWidth="40dip"
android:minHeight="72dip"
android:initialLayout="@layout/widget_layout" >
</appwidget-provider>
小部件布局.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView android:id="@+id/textView"
android:text="TEST"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
MyBatteryWidget.java
package main;
import android.app.Service;
import android.appwidget.AppWidgetManager;
import android.appwidget.AppWidgetProvider;
import android.content.BroadcastReceiver;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.BatteryManager;
import android.os.IBinder;
import android.util.Log;
import android.widget.RemoteViews;
import com.example.battery.R;
public class MyBatteryWidget extends AppWidgetProvider {
@Override
public void onUpdate(Context context, AppWidgetManager appWidgetManager,
int[] appWidgetIds) {
Log.d("TEST", "onUpdate");
context.getApplicationContext().startService(new Intent("com.example.battery.action.UPDATE"));
}
public static class BatteryUpdateService extends Service {
private static int level = 0;
private static int scale = 0;
private BroadcastReceiver receiver = new BroadcastReceiver(){
@Override
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (action.equals(Intent.ACTION_BATTERY_CHANGED)) {
level = intent.getIntExtra(BatteryManager.EXTRA_LEVEL, -1);
scale = intent.getIntExtra(BatteryManager.EXTRA_SCALE, -1);
Log.d("TEST", "receive");
updateViews(context);
}
}
};
private void updateViews(Context context) {
RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.widget_layout);
views.setTextViewText(R.id.textView, String.valueOf(level / scale));
ComponentName componentName = new ComponentName(context, MyBatteryWidget.class);
AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context);
appWidgetManager.updateAppWidget(componentName, views);
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
// TODO Auto-generated method stub
Log.d("TEST", "start");
registerReceiver(receiver, new IntentFilter(Intent.ACTION_BATTERY_CHANGED));
return super.onStartCommand(intent, flags, startId);
}
@Override
public IBinder onBind(Intent intent) {
// TODO Auto-generated method stub
return null;
}
}
}
日志猫
03-27 19:51:34.963: D/dalvikvm(608): Not late-enabling CheckJNI (already on)
03-27 19:51:35.043: E/Trace(608): error opening trace file: No such file or directory (2)
03-27 19:51:35.083: D/TEST(608): onUpdate
03-27 19:51:35.103: D/TEST(608): start
03-27 19:51:35.133: D/TEST(608): receive