How do I draw an arrowhead (in Android)?

How about using "Path myPath = new Path();" where you would give the x and y positions to create a triangle using lines and filling it. You can read about it, here is an example I took from somewhere.

// create and draw triangles// use a Path object to store the 3 line segments// use .offset to draw in many locations// note: this triangle is not centered at 0,0paint.setStyle(Paint.Style.STROKE);paint.setStrokeWidth(2);paint.setColor(Color.RED);Path path = new Path();path.moveTo(0, -10);path.lineTo(5, 0);path.lineTo(-5, 0);path.close();path.offset(10, 40);canvas.drawPath(path, paint);path.offset(50, 100);canvas.drawPath(path, paint);// offset is cumlative// next draw displaces 50,100 from previouspath.offset(50, 100);canvas.drawPath(path, paint);

My Arrow Drawing code, maybe it can be of some use for somebody:

    /** * Draw an arrow * change internal radius and angle to change appearance * - angle : angle in degrees of the arrows legs * - radius : length of the arrows legs * @author Steven Roelants 2017 * * @param paint * @param canvas * @param from_x * @param from_y * @param to_x * @param to_y */private void drawArrow(Paint paint, Canvas canvas, float from_x, float from_y, float to_x, float to_y){    float angle,anglerad, radius, lineangle;    //values to change for other appearance *CHANGE THESE FOR OTHER SIZE ARROWHEADS*    radius=10;    angle=15;    //some angle calculations    anglerad= (float) (PI*angle/180.0f);    lineangle= (float) (atan2(to_y-from_y,to_x-from_x));    //tha line    canvas.drawLine(from_x,from_y,to_x,to_y,paint);    //tha triangle    Path path = new Path();    path.setFillType(Path.FillType.EVEN_ODD);    path.moveTo(to_x, to_y);    path.lineTo((float)(to_x-radius*cos(lineangle - (anglerad / 2.0))),            (float)(to_y-radius*sin(lineangle - (anglerad / 2.0))));    path.lineTo((float)(to_x-radius*cos(lineangle + (anglerad / 2.0))),            (float)(to_y-radius*sin(lineangle + (anglerad / 2.0))));    path.close();    canvas.drawPath(path, paint);}

I try this code it has been working perfectly:

switch (event.getAction()){   case MotionEvent.ACTION_DOWN:        mPath.reset();        mPath.moveTo(x, y);        mX = x;        mY = y;        startPoint = new PointF(event.getX(), event.getY());        endPoint = new PointF();        invalidate();        break;    case MotionEvent.ACTION_MOVE:            float dx = Math.abs(x - mX);        System.out.println("action move");        float dy = Math.abs(y - mY);        if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE)        {        //  currentDrawingPath.path.quadTo(mX,mY,(x + mX)/2, (y + mY)/2);        }        mX = x;        mY = y;          endPoint.x = event.getX();          endPoint.y = event.getY();          isDrawing = true;          invalidate();        break;    case MotionEvent.ACTION_UP:           mPath.lineTo(mX, mY);           float deltaX =   endPoint.x-startPoint.x;           float deltaY =   endPoint.y-startPoint.y;           float frac = (float) 0.1;     float point_x_1 = startPoint.x + (float) ((1 - frac) * deltaX + frac * deltaY);     float point_y_1 = startPoint.y + (float) ((1 - frac) * deltaY - frac * deltaX);           float point_x_2 = endPoint.x;           float point_y_2 = endPoint.y;     float point_x_3 = startPoint.x + (float) ((1 - frac) * deltaX - frac * deltaY);     float point_y_3 = startPoint.y + (float) ((1 - frac) * deltaY + frac * deltaX);           mPath.moveTo(point_x_1, point_y_1);           mPath.lineTo(point_x_2, point_y_2);           mPath.lineTo(point_x_3, point_y_3);           mPath.lineTo(point_x_1, point_y_1);           mPath.lineTo(point_x_1, point_y_1);            mCanvas.drawPath(mPath, ppaint);            endPoint.x = event.getX();            endPoint.y = event.getY();            isDrawing = false;            invalidate();        break;    default:        break;}