Question

Can anyone explain to me why this is happening?

I have a fairly simple class extending TextView. When I set the background colour to Color.BLUE, padding works fine. When I change the background resource to android.R.drawable.list_selector_background, my padding is no longer applied. What the F?

Here is my UI class:

public class GhostDropDownOption extends TextView {

    TextView text_view;


    public GhostDropDownOption(Context context, AttributeSet attrs) {
        super(context, attrs);
        setup(context);
    }


    public GhostDropDownOption(Context context) {
        super(context);
        setup(context);
    }


    private void setup(Context context) {
        this.setClickable(false);
        // THE 2 LINES BELOW ARE THE ONLY THING I'M CHANGING
        //this.setBackgroundResource(android.R.drawable.list_selector_background);
        this.setBackgroundColor(Color.BLUE);
    }
}

And I’m using it in the layout like this:

<trioro.voyeur.ui.GhostDropDownOption
    android:id="@+id/tv_dropdown_option_1"
    android:layout_width="fill_parent"
    android:layout_height="0dip"
    android:layout_weight="1"
    android:gravity="center_vertical"
    android:text="@string/request_control_dropdown_option_1"
    android:textColor="#000000"
    android:padding="10dip"/>

And this is the result of changing the background:

Answer 1

The call to:

this.setBackgroundResource(android.R.drawable.list_selector_background);

will remove any previosly set padding (this is to make it work properly with 9-patch assets).

Try to set the padding in code after the line above, like this:

this.setPadding(PADDING_CONSTANT, PADDING_CONSTANT, PADDING_CONSTANT, PADDING_CONSTANT);

Just remember that the values sent to setPadding is in pixels NOT dip!