Custom Arc seekbar / slider

ArcProgress.java

class ArcProgress extends View {

	Context cx;
	float width;
	float height;
	float center_x, center_y;
	final RectF oval = new RectF();
	final RectF touchArea = new RectF();
	float sweep = 0;
	float left, right;
	int percent = 0;
	int oldPercent = 0;

	public ArcProgress(Context context) {
		super(context);
		cx = context;

	}

	public int getPercentage() {
		return percent;
	}

	@Override
	protected void onDraw(Canvas canvas) {
		super.onDraw(canvas);
		setBackgroundColor(0xfff0ebde);
		width = (float) getWidth();
		height = (float) getHeight();
		float radius;
		if (width > height) {
			radius = height / 3;
		} else {
			radius = width / 3;
		}
		Paint paint = new Paint();
		paint.setAntiAlias(true);
		paint.setColor(0xffd2c8b6);
		paint.setStrokeWidth(35);
		paint.setStyle(Paint.Style.STROKE);
		center_x = width / 2;
		center_y = height / 2;
		left = center_x - radius;
		float top = center_y - radius;
		right = center_x + radius;
		float bottom = center_y + radius;
		Log.d("left", String.valueOf(left));
		Log.d("right", String.valueOf(right));
		oval.set(left, top, right, bottom);
		canvas.drawArc(oval, 180, 180, false, paint);
		paint.setStrokeWidth(10);
		paint.setColor(0xffe0524d);
		canvas.drawArc(oval, 180, sweep, false, paint);
		paint.setColor(0xff333333);
		paint.setTextSize(30);
		paint.setStrokeWidth(1);
		paint.setStyle(Paint.Style.FILL);
		Typeface cFont = Typeface.createFromAsset(cx.getAssets(),
				"fonts/bebas.ttf");
		paint.setTypeface(cFont);
		canvas.drawText("0%", left - 10, center_y + 50, paint);
		canvas.drawText("100%", right - 20, center_y + 50, paint);
		paint.setTextSize(40);
		canvas.drawText(String.valueOf(percent) + "%", right - 20, top, paint);

	}

	@Override
	public boolean onTouchEvent(MotionEvent event) {

		if (event.getAction() == MotionEvent.ACTION_DOWN) {

		} else if (event.getAction() == MotionEvent.ACTION_UP) {

		} else if (event.getAction() == MotionEvent.ACTION_MOVE) {

			float xPosition = event.getX();
			float yPosition = event.getY();
			if (oval.contains(xPosition, yPosition)) {

				float x = event.getX() - left;
				float s = x * 100;
				float b = s / oval.width();
				percent = Math.round(b);
				sweep = (180 / 100.0f) * (float) percent;
				invalidate();
			} else {
				if (xPosition < left) {
					percent = 0;
					sweep = (180 / 100.0f) * (float) percent;
					invalidate();
				}
				if (xPosition > right) {
					percent = 100;
					sweep = (180 / 100.0f) * (float) percent;
					invalidate();
				}
			}

		}

		return true;
	}
}