How to create toast from IntentService? It gets stuck on the screen

Question

I'm trying to have my IntentService show a Toast message, but when sending it from the onHandleIntent message, the toast shows but gets stuck and the screen and never leaved. I'm guessing its because the onHandleIntent method does not happen on the main service thread, but how can I move it?

Has anyone has this issue and solved it?

Nutbrown

Possible duplicate of Toast created in an IntentService never goes away – Bronwyn

Answer 1

in onCreate() initialize a Handler and then post to it from your thread.

private class DisplayToast implements Runnable{
  String mText;

  public DisplayToast(String text){
    mText = text;
  }

  public void run(){
     Toast.makeText(mContext, mText, Toast.LENGTH_SHORT).show();
  }
}
protected void onHandleIntent(Intent intent){
    ...
  mHandler.post(new DisplayToast("did something")); 
}

Uxmal

What is your mContext initialized to? – Cogon

It is a reference to the service. – Uxmal

the toast made this way won't go away. is there anything I should add except the code above? – Irritation

@Irritation that is an interesting bug, you can always keep a reference to the toast and call its cancel method – Uxmal

@AvinashR to combat that issue, just use the Handler constructor that takes a Looper. mHandler = new Handler(Looper.getMainLooper()); – Uxmal

Answer 2

Here is the full IntentService Class code demonstrating Toasts that helped me:

package mypackage;

import android.app.IntentService;
import android.content.Intent;
import android.os.Handler;
import android.os.Looper;
import android.widget.Toast;

public class MyService extends IntentService {
    public MyService() { super("MyService"); }

    public void showToast(String message) {
        final String msg = message;
        new Handler(Looper.getMainLooper()).post(new Runnable() {
            @Override
            public void run() {
                Toast.makeText(getApplicationContext(), msg, Toast.LENGTH_LONG).show();
            }
        });
    }

    @Override
    protected void onHandleIntent(Intent intent) {
        showToast("MyService is handling intent.");
    }
}

Caneghem

is not possible to create a Toast using an Application-Context ... you need an activity to do that kind of stuff ... – Proctor

@Proctor I provided a real-life working code snippet. – Caneghem

Answer 3

Use the Handle to post a Runnable which content your operation

protected void onHandleIntent(Intent intent){
    Handler handler=new Handler(Looper.getMainLooper());
    handler.post(new Runnable(){
    public void run(){ 
        //your operation...
        Toast.makeText(getApplicationContext(), "hello world", Toast.LENGTH_SHORT).show();
    }  
}); 

Overtrick