spinner.setSelection 不调用 setOnItemSelectedListener 函数

Question

I have 3 spinners. Each spinner get new data when a previous spinner is set. So i have nested setOnItemSelectedListener on these spinner.

my code is kind of like this:

 MyAdapter adapter = new MyAdapter(getActivity(), R.layout.res_custom_new, categories, response.body(), pos);
 adapter.setDropDownViewResource(R.layout.res_custom_new);
 spinner.setAdapter(adapter);
 spinner.setSelection(pos);

 spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
     @Override
     public void onItemSelected(AdapterView << ? > adapterView, View view, int ii, long l) {
         //some code A
         second_spinner_destination_function();
     }
 });

second_spinner_destination_function() contain 2 more spinner

public void second_spinner_destination_function() {
 //some code
 ArrayAdapter < String > dataAd = new ArrayAdapter < String > (getActivity(), android.R.layout.simple_spinner_item, getDestination);
 dataAd.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
 spinnerdestination.setAdapter(dataAd);
 spinnerdestination.setSelection(posfrom);
 //code block B
 spinnerdestination.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
     @Override
     public void onItemSelected(AdapterView << ? > adapterView, View view, final int i, long l) {

         //some code C
         ArrayAdapter < String > dataAdapter2 = new ArrayAdapter < String > (getActivity(), android.R.layout.simple_spinner_item, getVesselName);
         dataAdapter2.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
         third_spinnervessels.setAdapter(dataAdapter2);
         third_spinnervessels.setSelection(posvessel);
         spinnervessels.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
             @Override
             public void onItemSelected(AdapterView << ? > adapterView, View view, int iii, long l) {

             }
         });
         //some code D              

     }
 });
 //some Code E
 }

The above code is first called during onCreate function. After that if a dropdown changes then the relevant code runs.

Now here's my problem: Since all these lines of code have run once during oncreate, so the listeners on spinners are set. Now lets say i clicked the first spinner and changed something. so it will now 'code block A' and then call second_spinner_destination_function().

In second_spinner_destination_function() when the line spinnerdestination.setSelection(posfrom) is encountered, it should run its onItemSelected() function immediately but instead it goes to run code block B then sets new listener on it and then runs 'code block E' and after that runs the onItemSelected() of second spinner.

I have made sure that spinnerdestination.setSelection(posfrom) is getting new index and not same as old index. Any idea why it is running in this sequence?

Answer 1

You have to separate the spinners because this method immediately runs on spinner attached to the adapter

spinnervessels.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() { @Override public void onItemSelected(AdapterView << ? > adapterView, View view, int iii, long l) {

       }