从小部件启动活动 [英] Launching activity from widget

问题描述

我正在尝试做一些应该很容易的事情，但它让我发疯了.我试图在按下主屏幕小部件时启动一个活动，例如小部件的配置活动.我想我已经逐字跟踪了 Android 开发者网站上的教程，甚至还有一些非官方教程，但我一定遗漏了一些重要的东西，因为它不起作用.

I'm trying to do something which really ought to be quite easy, but it's driving me crazy. I'm trying to launch an activity when a home screen widget is pressed, such as a configuration activity for the widget. I think I've followed word for word the tutorial on the Android Developers website, and even a few unofficial tutorials as well, but I must be missing something important as it doesn't work.

代码如下:

public class VolumeChangerWidget extends AppWidgetProvider {

public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds){
    final int N = appWidgetIds.length;

    for (int i=0; i < N; i++) {
        int appWidgetId = appWidgetIds[i];

        Log.d("Steve", "Running for appWidgetId " + appWidgetId);
        Toast.makeText(context, "Hello from onUpdate", Toast.LENGTH_SHORT);
        Log.d("Steve", "After the toast line");

        Intent intent = new Intent(context, WidgetTest.class);

        PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, intent, 0);

        RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.widget);
        views.setOnClickPendingIntent(R.id.button, pendingIntent);

        appWidgetManager.updateAppWidget(appWidgetId, views);
    }
}

}

将小部件添加到主屏幕时，Logcat 会显示两条调试行，但不会显示 Toast.(任何想法为什么不呢?)然而，更令人烦恼的是，当我然后单击与 PendingIntent 关联的按钮时，什么也没有发生.我知道WidgetTest"活动可以运行，因为如果我从主活动中设置一个意图，它会正常启动.

When adding the widget to the homescreen, Logcat shows the two debugging lines, though not the Toast. (Any ideas why not?) However, more vexing is that when I then click on the button with the PendingIntent associated with it, nothing happens at all. I know the "WidgetTest" activity can run because if I set up an Intent from within the main activity, it launches fine.

以防万一，这里是 Android 清单文件:

In case it matters, here is the Android Manifest file:

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.steve"
android:versionCode="1"
android:versionName="1.0">
<application android:icon="@drawable/icon" android:label="@string/app_name">
    <activity android:name=".Volume_Change_Program"
              android:label="@string/app_name">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>

    <activity android:name=".WidgetTest"
              android:label="@string/hello">
        <intent_filter>
            <action android:name="android.intent.action.MAIN"/>
            <category android:name="android.intent.category.LAUNCHER"/>
        </intent_filter>
    </activity>

    <receiver android:name=".VolumeChangerWidget" >
        <intent-filter>
            <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
        </intent-filter>
        <meta-data  android:name="android.appwidget.provider"
                    android:resource="@xml/volume_changer_info" />
    </receiver>

</application>
<uses-sdk android:minSdkVersion="3" />

有没有办法测试故障在哪里?IE.是按钮没有正确链接到 PendingIntent 的错误，还是 PendingIntent 或 Intent 没有找到 WidgetTest.class 等?

Is there a way to test where the fault is? I.e. is the fault that the button isn't linked properly to the PendingIntent, or that the PendingIntent or Intent isn't finding WidgetTest.class, etc?

非常感谢您的帮助！

史蒂夫

推荐答案

我遇到了同样的问题.我发现修复方法是通过 appwidget 管理器调用更新.这是如何在 onEnabled 中执行此操作的示例.似乎它需要在 onEnabled 和 onUpdated 中完成，以便在设备启动时您的点击意图也被初始化 - 幸运的是，在 onUpdated 中，参数已经提供了对管理器的引用.

I was having the same issue. I discovered that the fix is to call an update through the appwidget manager. here is an example of how to do that in onEnabled. It appears it needs to be done in both onEnabled and onUpdated so that when device is powering on your click intent is also intialized - in onUpdated the params already provide the reference to the manager, luckily.

@Override 
    public void onEnabled(Context context) {  
          //Log.v("toggle_widget","Enabled is being called"); 

          AppWidgetManager mgr = AppWidgetManager.getInstance(context); 
          //retrieve a ref to the manager so we can pass a view update 

          Intent i = new Intent(); 
          i.setClassName("yourdoman.yourpackage", "yourdomain.yourpackage.yourclass"); 
          PendingIntent myPI = PendingIntent.getService(context, 0, i, 0); 
          //intent to start service 

        // Get the layout for the App Widget 
        RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.togglelayout); 

        //attach the click listener for the service start command intent 
        views.setOnClickPendingIntent(R.id.toggleButton, myPI); 

        //define the componenet for self 
        ComponentName comp = new ComponentName(context.getPackageName(), ToggleWidget.class.getName()); 

        //tell the manager to update all instances of the toggle widget with the click listener 
        mgr.updateAppWidget(comp, views); 
} 

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