paint Canvas画笔、画布

Paint paint = new Paint();

设置画笔的颜色
paint.setColor(Color.RED);

矢量图[vector]，也叫做向量图，简单的说，就是缩放不失真的图像格式。

//创建一个矢量图Bitmap
Bitmap bitmap = Bitmap.createBitmap(300,300,Bitmap.Config.ARGB_8888);

Canvas canvas = new Canvas(bitmap);

//拿到ImageView的视图，并设置他的图片为刚才设置的图片
ImageView imageView = (ImageView) findViewById(R.id.imageView);

imageView.setImageBitmap(bitmap);

//圆心坐标，半径，画笔
canvas.drawCircle(100,100,100,paint);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC));

Rect rect = new Rect(100,100,400,400);
//参数1.形状，  2.那个画笔
canvas.drawRect(rect,paint);

RectF rect3 = new RectF(270,100,300,210);
canvas.drawRoundRect(rect3,10f,10f,paint);

RectF rectF = new RectF(100,20,250,160);
canvas.drawArc(rectF,180,180,true,paint);

paint.setColor(Color.BLACK);

参数1、2：起始点的坐标

参数3、4终点的坐标

参数5：画笔
canvas.drawLine(0,200,600,600,paint);