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  • Android UI SurfaceView的使用-绘制单个图型或多个图形

    新建MyView类继承自SurfaceView:

    public class MyView extends SurfaceView implements SurfaceHolder.Callback {
    
    	private Paint paint;
    	public MyView(Context context) {
    		super(context);
    		paint=new Paint();
    		paint.setColor(Color.RED);
    		getHolder().addCallback(this);
    	}
    	public void draw(){
    		//绘制画布前锁定画布
    		Canvas canvas=getHolder().lockCanvas();
    		canvas.drawColor(Color.WHITE);
    		//从画布的50x50开始绘制,绘制到100x100,绘制面积50x50
    		canvas.drawRect(50, 50, 100, 100, paint);
    		//将第一条线顺时针旋转90度
    		canvas.save(); //将画布处可编辑状态
    		canvas.rotate(90,getWidth()/2,getHeight()/2); //按中心点进行旋转
    		canvas.drawLine(0, getHeight()/2, getWidth(), getHeight(), paint);
    		canvas.restore();// 将画布复原
    		canvas.drawLine(0, getHeight()/2+100, getWidth(), getHeight()+100, paint);
    		
    		//绘制画布结束后解锁画布
    		getHolder().unlockCanvasAndPost(canvas);
    	}
    	@Override
    	public void surfaceChanged(SurfaceHolder holder, int format, int width,
    			int height) {
    	}
    
    	@Override
    	public void surfaceCreated(SurfaceHolder holder) {
    		draw();
    	}
    
    	@Override
    	public void surfaceDestroyed(SurfaceHolder holder) {
    	}
    MainActivity:

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(new MyView(this));
        }


    效果:












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  • 原文地址:https://www.cnblogs.com/raphael5200/p/5114775.html
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