How do I draw an arrowhead (in Android)?

Question

I\'m fairly new to Android and have been toying around with Canvas. I\'m attempting to draw an arrow but I\'m only having luck with drawing the shaft, none of the arrowhead

Answer 1

Copypast from this answer https://stackoverflow.com/a/29383352/9975029

private void fillArrow(Canvas canvas, float x0, float y0, float x1, float y1) {
    paint.setStyle(Paint.Style.FILL);

    float deltaX = x1 - x0;
    float deltaY = y1 - y0;
    double distance = Math.sqrt((deltaX * deltaX) + (deltaY * deltaY));
    float frac = (float) (1 / (distance / 30));

    float point_x_1 = x0 + (float) ((1 - frac) * deltaX + frac * deltaY);
    float point_y_1 = y0 + (float) ((1 - frac) * deltaY - frac * deltaX);

    float point_x_2 = x1;
    float point_y_2 = y1;

    float point_x_3 = x0 + (float) ((1 - frac) * deltaX - frac * deltaY);
    float point_y_3 = y0 + (float) ((1 - frac) * deltaY + frac * deltaX);

    Path path = new Path();
    path.setFillType(Path.FillType.EVEN_ODD);

    path.moveTo(point_x_1, point_y_1);
    path.lineTo(point_x_2, point_y_2);
    path.lineTo(point_x_3, point_y_3);
    path.lineTo(point_x_1, point_y_1);
    path.lineTo(point_x_1, point_y_1);
    path.close();

    canvas.drawPath(path, paint);
}