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multithreading - Android - howto pass data to the Runnable in runOnUiThread?

I need to update some UI and do it inside of the UI thread by using runOnUiThread
Now the data for the UI comes from the other Thread, represented by data here.

How can i pass the data to the Runnable, so tht they can be used to update the UI? Android doesn't seem to allow using data directly. Is there an elegant way to do this?

public void OnNewSensorData(Data data) {

    runOnUiThread(new Runnable() {
        public void run() {
            //use data
        }
    });
}

My solution was creating a fioeld private Data sensordata inside of the runnable, and assigning data to it. This works only, if the original Data data is final.

public void OnNewSensorData(final Data data) {

    runOnUiThread(new Runnable() {
        private Data sensordata = data;
        public void run() {
            //use sensordata which is equal to data
        }
    });
}
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1 Answer

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The problem you found is that

Inner classes in Java capture ("close over") the lexical scope in which they are defined. But they only capture variables that are declared "final".

If this is clear as mud, there's a good discussion of the details here: Cannot refer to a non-final variable inside an inner class defined in a different method

But your solution looks fine. In addition, provided that data is final, you could simplify the code to this:

public void OnNewSensorData(final Data data) {
    runOnUiThread(new Runnable() {
        public void run() {
            // use data here
            data.doSomething();
        }
    });
}

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