How to disable onItemSelectedListener to be invoked when setting selected item by code

Question

Just wondering how you handle the following problem: a result is calculated depending on two spinners\' selected items. To handle the UI things, i.e. a user picks a new item in

Answer 1

I have an easier, and I think, better solution. Since I had to refresh the spinners even after initialization, this is a more generic approach. Please refer the accepted answer:

Undesired onItemSelected calls

Answer 2

Okay, I got it working the way I want to now.

The thing to understand here (and I did not when I was writing that question...) is that everything in Android runs in one thread - the UI thread.

Meaning: even though you set Spinner's values here and there: they are only updated (visually) and their listeners are only called after all methods you're currently in (like onCreate, onResume or whatever) are finished.

This allows the following:

• keep the selected positions in field variables. (like currentPos1, currentPos2)
• the listeners onItemSelectedListener() call a method like refreshMyResult() or whatever.
• when setting positions programmatically, set the spinners and call your own refresh method manually right after that.

The refreshMyResult() method looks like this:

int newPos1 = mySpinner1.getSelectedItemPosition();
int newPos2 = mySpinner2.getSelectedItemPosition();
// only do something if update is not done yet
if (newPos1 != currentPos1 || newPos2 != currentPos2) {
    currentPos1 = newPos1;
    currentPos2 = newPos2;

    // do whatever has to be done to update things!

}

Because the listeners will be called later - and by then, the remembered position in currentPos is already updated - nothing will happen and no unnecessary update of anything else will take place. When a user selects a new value in one of the spinners, well - the update will be performed accordingly!

That's it! :-)

Ahh - one more thing: the answer to my question is: No. The listeners cannot be disabled (easily) and will be called whenever a value is changed.

Answer 3

It is very easy you can call the Spinner.setSelection(int position, boolean animate) method with false so the listeners will not react on the change.

Answer 4

I created a library that help for all, that no need to call item onClick action in Spinner For example:

spinner.setSelection(withAction,position);

where withAction is a boolean flag, that used for call or not item action

Link on Github: https://github.com/scijoker/spinner2

Answer 5

My solution is very easy. First initialize a global boolean variable.

boolean shouldWork = true;

Then use below code in your onCreate() method.

Spinner spinner = findViewById(R.id.spinner);
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
    @Override
    public void onItemSelected(AdapterView adapter, View v, int i, long lng) {
        if (shouldWork) {
               // Do your actions here
        }
        else
            shouldWork = true;
    }
    public void onNothingSelected(AdapterView<?> parentView)  {

    }
});

Now you can use the setSelection method in everwhere without invoking the onItemSelected() method by below code.

shouldWork = false;
spinner.setSelection(0);

Answer 6

Spinner.setSelection(int position, boolean animate) does trigger the listener on 4.3