Question

I want to stop a Thread when the User leaves the Activity. It sounds so simple but no function, which i tried, works.

I start the Activity with the Code

lovi = new Intent(getApplicationContext(), listoverview.class);
lovi.putExtra("reloadAll", true);
startActivity(lovi);

In the onCreate of the listoverview i start the Thread with the Code

rlMF.start();

And rlMF looks like this:

public Thread rlMF = new Thread(new Runnable() {
    public void run() {
        reloadMissingFiles();
    }
});

I tried in the onPause to use rlMF.stop(), .interrupt(), .suspend. Nothing stops it.

Answer 1

You have to add some flag to to stop it. Stopping thread by other means might have dire consequences, like resource leaks.

For example:

volatile boolean activityStopped = false;

When creating runnable:

public Thread rlMF = new Thread(new Runnable() { 

    public void run() {
        while (!activityStopped) {
        // reloadMissingFiles() should check the flag in reality
            reloadMissingFiles(); 
        }
    }
});

In onPause():

protected void onPause(){
    super.onPause();
    activityStopped = true;
}