java - 如何只允许小部件android的单个实例

Question

我想允许添加一个小部件，我尝试放置一个 boolean 标志并且我有:

WidgetConfig 内部:

public final static String ADDED_KEY = "IsAdded";
public static boolean isAdded = false;

onCreate(在 WidgetConfig 内部)

isAdded = prefs.getBoolean(ADDED_KEY, false);       
    if (isAdded){
        Toast.makeText(this.getApplicationContext(), "Only one Widget", Toast.LENGTH_SHORT).show();
        finish();
    }
 [...]
editor.putBoolean(ADDED_KEY, true); //disable adding here
editor.commit();

在 WidgetProvider 内部扩展了 AppWidgetProvider

public void onDisabled(Context context) {

    super.onDisabled(context);
    [...]
//cancel alarm
   configEditor.putBoolean(WidgetConfig.ADDED_KEY, false); //enable adding here
    configEditor.commit();
}

public void onDeleted(Context context, int[] appWidgetIds){
super.onDeleted(context, appWidgetIds);
//I should not need this if there is only one widget
}

但它并不总是有效。 我能怎么做？谢谢

Answer 1

直接从 AppWidgetManager 获取您添加的小部件的 ID，并检查您的配置 Activity 中已经添加了多少。

int[] ids = AppWidgetManager.getInstance(getApplicationContext()).getAppWidgetIds(
            new ComponentName(getApplicationContext(), YOUR_WIDGET.class));

    if(ids.length > 0){
        //do not add the widget
    }else{
        //add the widget
    } 

这就是我检查是否有任何我的小部件实例的通常做法。