RoundedProgressBar

package com.example.drawtest;

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.LinearGradient;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.Point;
import android.graphics.RectF;
import android.graphics.Shader;
import android.view.View;

public class RoundedProgressBar extends View {
	Paint mBgPaint;
	Paint mProgressPaint;

	Point mCenter = null;

	RectF mOuterOven = null;
	RectF mInnerOven = null;
	int THICKNESS = 25;

	int mRadius;
	float mProgress = 0.9f;

	public RoundedProgressBar(Context context) {
		super(context);
		float density = getResources().getDisplayMetrics().density;
		THICKNESS *= density;
		
		setBackgroundColor(Color.TRANSPARENT);
		mBgPaint = new Paint();
		mBgPaint.setStyle(Paint.Style.FILL);
		mBgPaint.setColor(Color.rgb(36, 33, 38));
		mBgPaint.setAntiAlias(true);

		mProgressPaint = new Paint(mBgPaint);
		mProgressPaint.setColor(Color.RED);
	}

	@Override
	protected void onSizeChanged(int w, int h, int oldw, int oldh) {
		super.onSizeChanged(w, h, oldw, oldh);
		mOuterOven = new RectF(0, 0, w, w);
		mInnerOven = new RectF(THICKNESS, THICKNESS, w - THICKNESS, w - THICKNESS);
		mCenter = new Point(w / 2, w / 2);
		mRadius = w/2-THICKNESS/2;
		mProgressPaint.setShader(new LinearGradient(0,0,w,0,Color.rgb(109,198,34),Color.rgb(233, 84, 47),Shader.TileMode.CLAMP));
	}

	@Override
	protected void onDraw(Canvas canvas) {
		drawArc(canvas, 120, 300, mBgPaint);
		drawArc(canvas, 120, 300 * mProgress, mProgressPaint);
		super.onDraw(canvas);
	}
	
	private void drawArc(Canvas canvas, float startAngle, float sweepDegrees,
			Paint paint) {
		Path path = new Path();

		Point startPoint = calculatePointOnArc(mCenter.x, mCenter.y, mRadius,
				startAngle);
		Point endPoint = calculatePointOnArc(mCenter.x, mCenter.y, mRadius,
				startAngle + sweepDegrees);

		path.arcTo(mOuterOven, startAngle, sweepDegrees);
		path.arcTo(mInnerOven, startAngle + sweepDegrees, -sweepDegrees);

		path.addCircle(startPoint.x, startPoint.y, THICKNESS / 2,
				Path.Direction.CW);
		path.addCircle(endPoint.x, endPoint.y, THICKNESS / 2,
				Path.Direction.CW);

		path.close();

		canvas.drawPath(path, paint);
	}

	// this is to calculate the end points of the arc
	private Point calculatePointOnArc(int circleCeX, int circleCeY,
			int circleRadius, float endAngle) {
		Point point = new Point();
		double endAngleRadian = endAngle * (Math.PI / 180);

		int pointX = (int) Math.round((circleCeX + circleRadius
				* Math.cos(endAngleRadian)));
		int pointY = (int) Math.round((circleCeY + circleRadius
				* Math.sin(endAngleRadian)));

		point.x = pointX;
		point.y = pointY;

		return point;
	}

}