Android widget background color not updating - android-widget

Question

I want to change the widget background transparency dynamically. The user can define a custom value in percent in my SettingsActivity. After I call updateWidget() from my activity the widget does not update immediately. It is only working if I re-add the widget.
When I set a breaking I see that updateWidgetListView() is called.
widget_layout_black.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/widget_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<LinearLayout
android:layout_width="match_parent"
android:background="#drawable/primary_rounded_background_black"
android:layout_height="wrap_content">
<TextView
android:id="#+id/newTaskButton"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:clickable="false"
android:layout_gravity="center_vertical"
android:textIsSelectable="false"
android:fontFamily="sans-serif-light"
android:layout_marginBottom="2dp"
android:paddingTop="5dp"
android:paddingRight="10dp"
android:paddingLeft="10dp"
android:text="#string/tasks"
android:background="#color/black"
android:gravity="center_vertical"
android:textColor="#color/white"
android:textAppearance="?android:attr/textAppearanceMedium"
android:drawableRight="#drawable/add" />
</LinearLayout>
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/widgetScheduledTasksListView"
android:layout_marginRight="16dp"
android:layout_marginLeft="16dp"
android:layout_marginBottom="16dp"
android:dividerHeight="0dp"
android:divider="#null"
android:layout_centerHorizontal="true" />
<TextView
android:id="#+id/empty_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:text="#string/noScheduledTasks"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textColor="#000000"
android:visibility="gone" />
SettingsActivity.java
public void updateWidget() {
Intent intent = new Intent(this, WidgetProvider.class);
intent.setAction(AppWidgetManager.ACTION_APPWIDGET_UPDATE);
int[] ids = {R.xml.widgetinfo};
intent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_IDS, ids);
sendBroadcast(intent);
}
WidgetProvider.java
#Override
public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {
final int numberOfWidgets = appWidgetIds.length;
for (int i = 0; i < numberOfWidgets; ++i) {
RemoteViews remoteViews = updateWidgetListView(context,appWidgetIds[i]);
remoteViews.setOnClickPendingIntent(R.id.newTaskButton, getPendingSelfIntent(context, ACTION_NEW));
appWidgetManager.updateAppWidget(appWidgetIds[i], remoteViews);
}
super.onUpdate(context, appWidgetManager, appWidgetIds);
}
private RemoteViews updateWidgetListView(Context context, int appWidgetId) {
RemoteViews remoteViews = new RemoteViews(context.getPackageName(), R.layout.widget_layout_black);
Intent svcIntent = new Intent(context, WidgetService.class);
svcIntent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, appWidgetId);
svcIntent.setData(Uri.parse(svcIntent.toUri(Intent.URI_INTENT_SCHEME)));
remoteViews.setRemoteAdapter(appWidgetId, R.id.widgetScheduledTasksListView, svcIntent);
remoteViews.setEmptyView(R.id.widgetScheduledTasksListView, R.id.empty_view);
final Intent onClickIntent = new Intent(context, WidgetProvider.class);
onClickIntent.setAction(WidgetProvider.ACTION_OPEN);
onClickIntent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, appWidgetId);
onClickIntent.setData(Uri.parse(onClickIntent.toUri(Intent.URI_INTENT_SCHEME)));
final PendingIntent onClickPendingIntent = PendingIntent.getBroadcast(context, 0, onClickIntent, PendingIntent.FLAG_UPDATE_CURRENT);
remoteViews.setPendingIntentTemplate(R.id.widgetScheduledTasksListView, onClickPendingIntent);
remoteViews.setInt(R.id.widget_layout, "setBackgroundColor", getBackgroundWithTransparencyColor(context)); // Set background color
return remoteViews;
}
public int getBackgroundWithTransparencyColor(Context context) {
int white = context.getResources().getColor(R.color.white);
int transparencyInPercent = preferences.getInt(context.getResources().getString(R.string.keyWidgetBackgroundTransparency), 25);
try {
double value = 255.0 / 100 * (100 - transparencyInPercent);
return ColorUtils.setAlphaComponent(white, (int) value);
} catch (Exception e) {
e.printStackTrace();
return white;
}
}