如何执行长作业，然后从小部件onclick方法更新小部件？

Question

I'm logging to bank account and getting account balance. I calling this function from onUpdate in widget and running in AsyncTask

package com.example.oobe.widget.widgetexample;
public class ExampleAppWidgetProvider extends AppWidgetProvider 
{
    (...)

    public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[]  appWidgetIds) 
    {
        (...)
        if (notFromAsyncTask)
            new MyAsyncTask().execute(context);
        (...)
    }
    (...)
}

In method onPostExecute I want to call onUpdate widget and putExtra strings. How can I do this?

package com.example.oobe.widget.widgetexample;
public class MyAsyncTask extends AsyncTask<Object, Void, BGZ> 
{
    Context context;

    @Override
    protected BGZ doInBackground(Object... params) 
    {
        this.context = (Context)params[0];
        return GetSomething();
    }

    protected void onPostExecute(BGZ page)
    {
        Intent intent = new Intent(context, ExampleAppWidgetProvider.class);
        intent.setAction(AppWidgetManager.ACTION_APPWIDGET_UPDATE);
        intent.putExtra("result", result);
        intent.putExtra("webpage", webPage);
        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        context.startActivity(intent);
    }
    (...)
}

If I doing like above I'm getting error: .. Unable to find explicit activity class..

Can I do this from AsyncTask? Can I call widget_update (onUpdate) with params to recognize that is from my AsyncTask? Please give me little sample code (what to add to manifest if it must be broadcastreceiver and so on).

I have updated widget in onPostExecute but I think better method is to do that in ExampleAppWidgetProvider class?

Answer 1

If you are getting this error

Unable to find explicit activity class..

It may be due to this line

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

make sure ExampleAppWidgetProvider.class exist and

Context context = Activity.this;

or

Intent intent = new Intent(Activity.this, ExampleAppWidgetProvider.class); 

UPDATE

public class ExampleAppWidgetProvider extends AppWidgetProvider 
{

   //your code .......
//asynctask as an inner class
   public class MyAsyncTask extends AsyncTask<Object, Void, BGZ> 
{
  doInBackground(){}
onPreExecute(){}
onPostExecute(){

//save result 
// or call your methods you need to run after your async call
}
}

}