Question

I’m trying to figure out one simple thing: how to set a background color in Android view. Here is the code in an Activity:

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    View v = new  View(this);

    setContentView(v);
    v.setBackgroundColor(23423425);
}

and all I get is black screen.

Answer 1

The integer you set is easier represented as a hex value. The hex values are 0xAARRGGBB.

• A – represents the Alpha value which is how transparent the color is. A value of FF means it’s not transparent at all. A value of 00 means the color won’t be shown at all and everything behind it will be visible.

• R – Red value; self-explanatory

• G – Green value; self-explanatory

• B – Blue value; self-explanatory

What you entered in hex is 0x016569C1 which has an Alpha values of 1 (barely visible). Put, 0xFFFF0000 and you’ll have a red background.