Cannot get Color.HSVToColor to work on Android

android, hsv

Solution

Your draw should work fine. There must be something missing or something other than the draw that you are not doing right.

mpaint.setColor( Color.HSVToColor( new float[]{ 1f, 1f, 1f } ) );

The above should set color to red.

I have done similar to what you have done in onDraw() except that i changed the value and it works.

public class FingerPaintActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
MyView mv= new MyView(this);
setContentView(mv);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
class MyView extends View
{
    Context c;      
    private Paint mpaint;

public MyView(Context context) {
    super(context);
    c= context;
    mpaint= new Paint();
    //mpaint.setColor(Color.RED);
    mpaint.setColor( Color.HSVToColor( new float[]{ 0f, 0f, 0.5f } ) );
    mpaint.setStyle(Paint.Style.FILL);
 }

    @Override
    protected void onDraw(Canvas canvas) {
       canvas.drawRect(300, 100, 200, 300, mpaint);

    }
}
}

http://developer.android.com/reference/android/graphics/Color.html#HSVToColor%28int,%20float%5B%5D%29.

Problem

I've derived a class from `View` and implemented the `onDraw` method as follows: ``` protected void onDraw( Canvas canvas ) { Paint p = new Paint(); p.setColor( Color.HSVToColor( new float[]{ 1.f, 1.f, 1.f } ) ); p.setStyle( Paint.Style.FILL ); canvas.drawRect( area, p ); } ``` I'm expecting to see an however colored rectangle, but the screen stays white, no metter which values I try for hue, value and saturation. The variable `area` is a `RectF`. It's fine, because if I put color to `Color.RED`, it works. The Android documentation states on `Color.HSVToColor`: Convert HSV components to an ARGB color. Alpha set to 0xFF. hsv[0] is Hue [0 .. 360) hsv[1] is Saturation [0...1] hsv[2] is Value [0...1] If hsv values are out of range, they are pinned. I've tried lots of hue/saturation/value combinations, but the screen always remained blank. Furthermore I've tried the following, with same results: ``` float[] hsv = new float[ 3 ]; Color.colorToHSV( Color.RED, hsv ); Paint p = new Paint(); p.setColor( Color.HSVToColor( hsv ) ); p.setStyle( Paint.Style.FILL ); canvas.drawRect( area, p ); ``` What am I doing wrong?

Original source