如何单击按钮以启动微调器控件的ItemSelected事件？

Question

I have a spinner control with setOnItemSelectedListener in my app, when I select an item of the spinner, the event onItemSelected will be launched. Now I hope to click a button to launch the onItemSelected event, how can I do? Thanks!

spinnerFolder.setOnItemSelectedListener(new OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> arg0, View arg1,int arg2, long arg3) {
                //Do Business Logic
            }           
            @Override
            public void onNothingSelected(AdapterView<?> arg0) {
            }   
        });

Answer 1

Just call the following from your button listener:

spinnerFolder.getOnItemSelectedListener().onItemSelected(spinnerFolder, spinnerFolder.getSelectedView(), spinnerFolder.getSelectedItemPosition(), spinnderFolder.getSelectedItemId());

That's all :-)

Answer 2

The third parameter (int arg2) of onItemSelected for your spinner is the position, so you can get the current selection by

String selection = (String) mSpinnerAdapter.getItem(position);

or use mSpinner.getItemAtPosition(position) if you don't have a custom adapter.

Store the current selection somewhere and pick it up in the onClickListener for your button.

Answer 3

When you populate the spinner with some data, you will have some sort of list objects (Strings, custom object, whatever) in the SpinnerAdapter , you'll keep a reference to that list, let's call it: private List<Object> dataList = ...

First of all I would create a method that would handle the specific data object: protected void doBusinessLogic(Object myObj) { // do the things that make you happy }

Then call this from listener as:

spinnerFolder.setOnItemSelectedListener(new OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> arg0, View arg1,int arg2, long arg3)    {
                // args2 is the position from backed data list
                doBusinessLogic(dataList.get(args2));
            }           
            @Override
            public void onNothingSelected(AdapterView<?> arg0) {
            }   
        });

Then from button listener you would call above method again, but the object index you would get is from spinnerFolder.getSelectedItemPosition(); :

myButton.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                int dataIndex = spinnerFolder.getSelectedItemPosition();
                doBusinessLogic(dataList.get(index));
            }
        });