I need to create a border with rounded corners programatically by extending ShapeDrawable. I need to have a black border with rounded corners with the pixels on the outside being white and the inner pixels being transparent. The code I have at the moment has multiple problems, of which are that it does not create a smooth corner that is the same thickness as the border and that the outer pixels of the border are transparent and not white.
Here is a picture of the corners I am currently getting
Here is the code where I am passing Color.TRANSPARENT for 'fill' in the constructor:
public class CustomShape extends ShapeDrawable {
private final Paint fillpaint, strokepaint;
public CustomShape(int fill, int strokeWidth,int radius) {
super(new RoundRectShape(new float[] { radius, radius, radius, radius, radius, radius, radius, radius }, null, null));
fillpaint = new Paint(this.getPaint());
fillpaint.setColor(fill);
strokepaint = new Paint(fillpaint);
strokepaint.setStyle(Paint.Style.STROKE);
strokepaint.setStrokeWidth(strokeWidth);
strokepaint.setColor(Color.BLACK);
}
@Override
protected void onDraw(Shape shape, Canvas canvas, Paint paint) {
shape.draw(canvas, fillpaint);
shape.draw(canvas, strokepaint);
}
}
If you need evenly rounded corners (and from your example it seems you do) you can simply use GradentDrawable with a solid color
GradientDrawable gd = new GradientDrawable();
gd.setColor(Color.RED);
gd.setCornerRadius(10);
gd.setStroke(2, Color.WHITE);
view.setBackground(gd);
GradientDrawable documentation can be found here.
Edit: For each corner separately
You can specify radius of each corner separately using setCornerRadii (float[] radii)
method. "For each corner, the array contains 2 values, [X_radius, Y_radius]. The corners are ordered top-left, top-right, bottom-right, bottom-left. This property is honored only when the shape is of type RECTANGLE.
It is recommended to invoke mutate()
before changing this property.