12.26

package com.example.myapp;

 

import android.content.Context;

import android.graphics.Canvas;

import android.graphics.Color;

import android.graphics.Paint;

import android.view.SurfaceHolder;

import android.view.SurfaceView;

 

public class CustomSurfaceView extends SurfaceView implements SurfaceHolder.Callback {

 

    private SurfaceHolder surfaceHolder;

    private Paint paint;

    private DrawThread drawThread;

 

    public CustomSurfaceView(Context context) {

        super(context);

        init();

    }

 

    private void init() {

        surfaceHolder = getHolder();

        surfaceHolder.addCallback(this);

 

        paint = new Paint();

        paint.setColor(Color.RED);

        paint.setStyle(Paint.Style.FILL);

 

        drawThread = new DrawThread();

    }

 

    @Override

    public void surfaceCreated(SurfaceHolder holder) {

        drawThread.setRunning(true);

        drawThread.start();

    }

 

    @Override

    public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {

        // Respond to surface changes, if needed

    }

 

    @Override

    public void surfaceDestroyed(SurfaceHolder holder) {

        boolean retry = true;

        drawThread.setRunning(false);

        while (retry) {

            try {

                drawThread.join();

                retry = false;

            } catch (InterruptedException e) {

                e.printStackTrace();

            }

        }

    }

 

    private class DrawThread extends Thread {

        private boolean running = false;

 

        public void setRunning(boolean running) {

            this.running = running;

        }

 

        @Override

        public void run() {

            Canvas canvas;

            while (running) {

                canvas = null;

                try {

                    canvas = surfaceHolder.lockCanvas(null);

                    if (canvas != null) {

                        // Draw on the canvas

                        canvas.drawColor(Color.WHITE);

                        canvas.drawRect(100, 100, 200, 200, paint);

                    }

                } finally {

                    if (canvas != null) {

                        surfaceHolder.unlockCanvasAndPost(canvas);

                    }

                }

            }

        }

    }

}

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent"

    android:layout_height="match_parent">

 

    <com.example.myapp.CustomSurfaceView

        android:id="@+id/customSurfaceView"

        android:layout_width="match_parent"

        android:layout_height="match_parent" />

 

</RelativeLayout>