Android - How to draw an arc based gradient

Question

I am trying to create an arc (variable number of degrees) that gradually goes from one color to another. From example from blue to red:

Answer 1

To add to Yoav's solution.

On my Galaxy Nexus 4.2 stock Android, the solution given doesn't work.

If the array doesn't contain a 0.0f and 1.0f, it appears to be ignored.

My final solution was:

int[] colors = {Color.RED, Color.BLUE, Color.RED}; 
float[] positions = {0, Xf/360f, 1};

Answer 2

five years later, but the right way is make 0.749f with 0.750f of the separate line, simple code is like:

    val colors = intArrayOf(0xffff0000.toInt(), 0xff0000ff.toInt(), 0xffff0000.toInt(), 0xffff0000.toInt())
    val positions = floatArrayOf(0.0f, 0.749f, 0.750f, 1.0f)

Answer 3

The solution for this is to set the position of BLUE. This is done like so:

int[] colors = {Color.RED, Color.BLUE};
float[] positions = {0,1};
SweepGradient gradient = new SweepGradient(100, 100, colors , positions);

The problem here is that when setting the position of BLUE to '1' this does not mean that it will be positioned at the end of the drawn arc, but instead at the end of the circle of which the arc is part of. To solve this, BLUE position should take into account the number of degrees in the arc. So if I'm drawing an arc with X degrees, position will be set like so:

float[] positions = {0,Xf/360f};

So if X is 90, the gradient will place BLUE at 0.25 of the circle: