notifyappwidgetviewdatachanged 无法在我的小部件上的列表视图上工作

Question

我尝试了很多解决方案，但几周后我无法解决这个问题：为什么“notifyappwidgetviewdatachanged”不起作用？如何更新放置在我的小部件上的列表视图？我哪里错了？

这是我的课程。

小部件提供商：

public class Widget_Provider extends AppWidgetProvider
{
public static final String ACTION_MOSTRAORARI = "fACTION_TOAST";
public static final String EXTRA_STRING = "EXTRA_STRING";

@Override
public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {
    // There may be multiple widgets active, so update all of them
    for (int appWidgetId : appWidgetIds)
    {
        RemoteViews views = updateWidgetListView(context, appWidgetId);

        final Intent onItemClick = new Intent(context, Widget_Provider.class);
        onItemClick.setAction(ACTION_MOSTRAORARI);
        onItemClick.setData(Uri.parse(onItemClick.toUri(Intent.URI_INTENT_SCHEME)));
        final PendingIntent onClickPendingIntent = PendingIntent.getBroadcast(context, 0, onItemClick, PendingIntent.FLAG_UPDATE_CURRENT);
        views.setPendingIntentTemplate(R.id.myStopList, onClickPendingIntent);

        appWidgetManager.updateAppWidget(appWidgetId, views);
    }
    super.onUpdate(context, appWidgetManager, appWidgetIds);
}

public RemoteViews updateWidgetListView(Context context, int appWidgetId)
{
    RemoteViews remoteViews = new RemoteViews(context.getPackageName(), R.layout.widget);
    Intent svcIntent = new Intent(context, Widget_Service.class);
    svcIntent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, appWidgetId);
    svcIntent.setData(Uri.parse(svcIntent.toUri(Intent.URI_INTENT_SCHEME)));
    remoteViews.setRemoteAdapter(R.id.myStopList, svcIntent);
    return remoteViews;
}

@Override
public void onReceive(Context context, Intent intent)
{
    if (intent.getAction().equals(ACTION_MOSTRAORARI)) {

        if (MainUtils.isNewtworkAvailable(context)) 
        {
            String item = intent.getExtras().getString(EXTRA_STRING);
            Intent intentOrari = new Intent(context, Diag_MostraOrari.class);
            intentOrari.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
            context.startActivity(intentOrari);
        }
    }

    super.onReceive(context, intent);
}

@Override
public void onDeleted(Context context, int[] appWidgetIds) {}

@Override
public void onEnabled(Context context) {}

@Override
public void onDisabled(Context context) {}
}

小部件服务：

public class Widget_Service extends RemoteViewsService
{

@Override
public RemoteViewsFactory onGetViewFactory(Intent intent)
{
    Map<String, ArrayList<String>> map = new TreeMap<>(String.CASE_INSENSITIVE_ORDER);

    /* ---
    * Here i fetch data from a local db and store it on "map"
    */ ---

    return (new Widget_ListProvider(this.getApplicationContext(), intent, map));
}

}

列表提供者：

public class Widget_ListProvider implements RemoteViewsFactory
{
private Map<String, ArrayList<String>> map = new HashMap<>();
private ArrayList<ListItem_Widget> listItemList = new ArrayList<>();
private Context context = null;
private int appWidgetId;

public Widget_ListProvider(Context context, Intent intent, Map<String, ArrayList<String>> map) 
{
    this.map = map;
    this.context = context;
    appWidgetId = intent.getIntExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, AppWidgetManager.INVALID_APPWIDGET_ID);

    populateListItem();
}

//This function populate the arraylist "listItemList" by the data stored on "map"
private void populateListItem() { [...] }

@Override
public int getCount() {
    return listItemList.size();
}

@Override
public long getItemId(int position) {
    return position;
}

@Override
public RemoteViews getViewAt(int position)
{
    final RemoteViews remoteView = new RemoteViews(context.getPackageName(), R.layout.listitem_widget);
    ListItem_Widget listItem = listItemList.get(position);
    remoteView.setTextViewText(R.id.heading, listItem.heading);
    remoteView.setTextViewText(R.id.content, listItem.content);

    final Intent fillInIntent = new Intent();
    fillInIntent.setAction(Widget.ACTION_MOSTRAORARI);
    final Bundle bundle = new Bundle();
    bundle.putString(Widget.EXTRA_STRING, listItem.heading);
    fillInIntent.putExtras(bundle);
    remoteView.setOnClickFillInIntent(R.id.listrow, fillInIntent);

    return remoteView;
}


@Override
public RemoteViews getLoadingView() {
    return null;
}

@Override
public int getViewTypeCount() {
    return 1;
}

@Override
public boolean hasStableIds() {
    return true;
}

@Override
public void onCreate() {}

@Override
public void onDataSetChanged() {}

@Override
public void onDestroy() {}

}

我的列表视图自定义项目的 xml 仅包含两个文本视图：“标题”和“内容”。

我哪里错了？为什么当我从另一个活动中调用“notifyappwidgetviewdatachanged”时没有任何反应？

[编辑]

这就是我需要更新我的小部件的活动。

public class Diag_Line extends AppCompatActivity 
{
    //[...]

    @Override
    protected void onCreate(Bundle savedInstanceState) 
    {
        //[...]
        AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(getApplicationContext());
        ComponentName thisAppWidget = new ComponentName(getApplicationContext().getPackageName(), Widget.class.getName());
        int[] appWidgetIds = appWidgetManager.getAppWidgetIds(thisAppWidget);
        appWidgetManager.notifyAppWidgetViewDataChanged(appWidgetIds, R.id.myStopList);

        //"myStopList" is the id of my listview inside the widget xml.

        //[...]
    }
}

Answer 1

嗯，问题非常明显：在您的 RemoteViewsFactory 中，您有一个空方法

onDataSetChanged()

。但是当您触发

notifyAppWidgetViewDataChanged()

时，您会在

onDataSetChanged()

中收到回调。为了更好地理解，请检查这张图片。

如果 Diag_Line 是配置活动，只需进行如下操作：

 appWidgetManager.updateAppWidget(appWidgetIds, views); // views is a RemoteViews that you need to build
 appWidgetManager.notifyAppWidgetViewDataChanged(appWidgetIds, R.id.myStopList);

另请查看官方文档这里

更新 给你一些提示。如果您正在使用小部件，请将所有获取数据和填充 RemoteViews 放在后台（IntentService 是一个很好的方法）。因此，只需在此处制作 IntentService 并为小部件制作逻辑即可。如果您通过广播触发更新，请不要忘记将他设置为前台（仅适用于 Android O）。您还可以查看图书馆，它为您提供一切。

Answer 2

为了notifyAppWidgetViewDataChanged()能够正常工作

我们需要在RemoteViewSourceFactory的onDataSetChanged()方法中检索数据 像这样：

override fun onDataSetChanged() {
listOfArticles = newsDatabaseRepo.getSynchronouslySavedNews() as ArrayList<Articles>

}

按照这里

的建议

并且有一个方法可以在发生更改时刷新小部件：

private fun refreshWidget() {
    val appWidgetManager =
        AppWidgetManager.getInstance(applicationContext)
    val thisAppWidget = ComponentName(
        applicationContext.packageName,
        MyAppWidgetProvider::class.java.name
    )
    val appWidgetIds = appWidgetManager.getAppWidgetIds(thisAppWidget)
    appWidgetManager.notifyAppWidgetViewDataChanged(appWidgetIds, R.id.stack_view)
}

调用上述方法后，一旦我退出我的应用程序，我就能注意到我的小部件中的变化

因此，为了检查 onDataSetChanged 是否在 notificationAppWidgetViewDataChanged() 之后被调用 我保留了一个调试点并调用了 onDataSetChanged() 并按照此处的建议更新了列表here

Answer 3

更新我的小部件时也遇到类似的问题，它正在调用

onDataSetChanged

但不刷新布局。因此，就我而言，在使用远程视图进行更新之前，我必须将

updateAppWidget

设置为 null，如下所示：

   appWidgetManager.updateAppWidget(appWidgetId, null);
   appWidgetManager.updateAppWidget(appWidgetId, remoteViews);

看起来这里发生了某种缓存。

Answer 4

我所做的是，当 appwidget-with-the-list 的

appWidgetManager.notifyAppWidgetViewDataChanged

被调用时，稍有延迟后调用

onUpdate

。

例如：

override fun onUpdate(
        context: Context,
        appWidgetManager: AppWidgetManager,
        appWidgetIds: IntArray
    ) {
        super.onUpdate(context, appWidgetManager, appWidgetIds)
        GlobalScope.launch {
            delay(1000)
            notifyAppWidgetViewDataChanged(appWidgetIds, android.R.id.list)
        }
    }