How to clear color of a button?

Question

Not only how to clear color to default color of my button, but also in what moment in my code to do it? I've tried everything but no luck. When I click a button I set some green color with opacity. Now when I click next button the same happens but the first button is still set to green. I need it to revert to original color. I tried with:

button.getBackground().setColorFilter(null);

Here's my code:

final OnClickListener clickListener = new OnClickListener() {

           private Button buttonClicked;

           public void onClick(View v) {
               Button button = (Button) v;
               button.getBackground().setColorFilter(new LightingColorFilter(0xFFFFFFFF, 0x003333));

               if (buttonClicked == null) {
                   // first button is clicked
                   buttonClicked = button;
                   // only do stuff if buttons are in different layouts
               } else{
           if (!button.getParent ().equals(buttonClicked.getParent())) {
                // second button is clicked

            if(buttonClicked.getTag().equals(button.getTag()) ){

               // second button is clicked and same tag but different button

               Toast.makeText(Spojnice.this, "Correct", Toast.LENGTH_SHORT).show();
               button.getBackground().setColorFilter(new LightingColorFilter(0xFFFFFFFF, 0x66FF33));
               buttonClicked.getBackground().setColorFilter(new LightingColorFilter(0xFFFFFFFF, 0x66FF33));
               buttonClicked.setEnabled(false);
               button.setEnabled(false);
               buttonClicked = null;
               } else {
               //reset LightingColorFilter first
               Toast.makeText(Spojnice.this, "Wrong", Toast.LENGTH_SHORT).show();
               buttonClicked = null;

               }
              }else{

                  buttonClicked = button;
              }
           }
               }       
           };

Answer 1

I just made a simple program which toggles the light filter on and off.

Here is the Activity:

 Button buttonClicked = null;
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.main);
     }

     public void clickedButton(View v) {
         Button button = (Button)v;
         button.getBackground().setColorFilter(new LightingColorFilter(0xFFFFFFFF,
                                                                       0x66FF33));

         if (buttonClicked != null) {
             buttonClicked.getBackground().setColorFilter(null);
         }
         buttonClicked = button;

     }

and here is the XML

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="fill_parent"
              android:layout_height="fill_parent"
        >
    <TextView
            android:id="@+id/boss"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:text="Hello World, MyActivity"
            />
    <Button
            android:id="@+id/buttsky"
            android:layout_below="@id/boss"
            android:onClick="clickedButton"
            android:layout_width="200dp"
            android:layout_height="100dp"
            android:text="pushMe"
            />
    <Button
            android:id="@+id/buttground"
            android:layout_below="@id/buttsky"
            android:onClick="clickedButton"
            android:layout_width="200dp"
            android:layout_height="100dp"
            android:text="no, pushMe"
            />
</RelativeLayout>