How to modify the default button state in Android without affecting the pressed and selected states?

Question

I am trying to remove an ImageButton\'s background in only the default state. I\'d like the pressed and selected states to behave as usual so that they look correct on diffe

Answer 1

StateListDrawable replace = new StateListDrawable();

Drawable old = getBackground();
replace.addState(FOCUSED_STATE_SET, old);
replace.addState(SELECTED_STATE_SET, old);
replace.addState(PRESSED_STATE_SET, old);

replace.addState(StateSet.WILD_CARD, new ColorDrawable(Color.TRANSPARENT));

if (Build.VERSION.SDK_INT >= 16) {
    setBackground(replace);
} else {
    setBackgroundDrawable(replace);
}

Answer 2

Tom,

It's true that if you override the default state you also have to override the pressed and focused states. The reason is that the default android drawable is a selector, and so overriding it with a static drawable means that you lose the state information for pressed and focused states as you only have one drawable specified for it. It's super easy to implement a custom selector, though. Do something like this:

<selector
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/custombutton">

    <item
        android:state_focused="true"
        android:drawable="@drawable/focused_button" />
    <item
        android:state_pressed="true"
        android:drawable="@drawable/pressed_button" />
    <item
        android:state_pressed="false"
        android:state_focused="false"
        android:drawable="@drawable/normal_button" />
</selector>

Put this in your drawables directory, and load it like a normal drawable for the background of the ImageButton. The hardest part for me is designing the actual images.

Edit:

Just did some digging into the source of EditText, and this is how they set the background drawable:

public EditText(/*Context context, AttributeSet attrs, int defStyle*/) {
    super(/*context, attrs, defStyle*/);

            StateListDrawable mStateContainer = new StateListDrawable();

            ShapeDrawable pressedDrawable = new ShapeDrawable(new RoundRectShape(10,10));
            pressedDrawable.getPaint().setStyle(Paint.FILL);
            pressedDrawable.getPaint().setColor(0xEDEFF1);


            ShapeDrawable focusedDrawable = new ShapeDrawable(new RoundRectShape(10,10));
            focusedDrawable.getPaint().setStyle(Paint.FILL);
            focusedDrawable.getPaint().setColor(0x5A8AC1);

            ShapeDrawable defaultDrawable = new ShapeDrawable(new RoundRectShape(10,10));
            defaultDrawable.getPaint().setStyle(Paint.FILL);
            defaultDrawable.getPaint().setColor(Color.GRAY);



            mStateContainer.addState(View.PRESSED_STATE_SET, pressedDrawable);
            mStateContainer.addState(View.FOCUSED_STATE_SET, focusedDrawable);
            mStateContainer.addState(StateSet.WILD_CARD, defaultDrawable);

            this.setBackgroundDrawable(mStateContainer);
}

I'm sure you could adapt the idea to your purposes. Here is the page I found it on:

http://www.google.com/codesearch/p?hl=en#ML2Ie1A679g/src/android/widget/EditText.java