I want to preform a Toast
when a background task is completed, just to let the user know that it's finished.
I've made a new class for my asyncTask but i cannot use getApplicationContext()
within this class.
I'm using task.execute(getTempFile(this), getApplicationContext());
to run the tasks. getTempFile returns a File object, and i was trying to pass the context as a Context object.
My Task class has 3 variables AsyncTask<Object, Integer, Integer>
so the context is in the second object. However, this crashes the application.
Edit
public class LocationActivity extends Activity implements LocationListener {
protected void handleImage(Bitmap thumbnail){
PushDataToServer task = new PushDataToServer();
task.execute(getTempFile(this), getApplicationContext());
}
}
public class PushDataToServer extends AsyncTask<Object, Integer, Integer> {
Context context;
@Override
protected Integer doInBackground(Object... params) {
// TODO Auto-generated method stub
this.context = (Context) params[1];
File file = (File) params[0];
return null;
}
protected void onPostExecute(String result) {
Toast toast = Toast.makeText(this.context, "All done!", Toast.LENGTH_SHORT);
toast.show();
}
}
Pass a Context
object into the AsyncTask
's constructor.
Sample code:
public class MyTask extends AsyncTask<?, ? ,?> {
private Context mContext;
public MyTask(Context context) {
mContext = context;
}
}
and then, when you are constructing your AsyncTask
:
MyTask task = new MyTask(this);
task.execute(...);
Pass it in the constructor, not as a method parameter. Then you don't need to depend on the generic parameters.
Complete example: Reusable AsyncTask
You say your context is in the second object, yet your second object is Integer. Could this be your problem? Also - another suggestion is to put your AsyncTask class as a private inner class to your activity - that way I am pretty sure you will have access to getApplicationContext().
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