Question

I’m doing porting app from Iphone to Android related to RGB colors.

Is there any equivalent for CGColorGetComponents in Android?

Answer 1

I usually get my argb values manually by using bit level operations. You can wrap this in a helper method that returns it as an array if it’s more convenient.

public int[] getColorComponents(int color)
{       
    int alpha = (color >> 24) & 0xff;
    int red = (color >> 16) & 0xff;
    int green = (color >> 8) & 0xff;
    int blue = color & 0xff;
    return new int[] { alpha, red, green, blue };
}

If you need floats, you can do something like this

public float[] getColorComponents(int color)
{       
    int alpha = (color >> 24) & 0xff;
    int red = (color >> 16) & 0xff;
    int green = (color >> 8) & 0xff;
    int blue = color & 0xff;
    float a = (float) alpha / 255;
    float r = (float) red / 255;
    float g = (float) green / 255;
    float b = (float) blue / 255;
    return new float[] { a, r, g, b };
}

If you’re doing this many times (such as looping through the pixels in a Bitmap), you probably want to use a single array and pass it in, replacing the values in the method instead of instantiating a new array.