代码
BasicCanvas.java
package com.Diamond.canvas;
import android.view.SurfaceView;
import android.view.SurfaceHolder;
import android.graphics.Bitmap;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.Color;
public class BasicCanvas extends SurfaceView implements SurfaceHolder.Callback {
public class DrawThread extends Thread {
@Override
public void run() {
while(true) {
int bw = bitmap.getWidth();
int bh = bitmap.getHeight();
Canvas canvas = getCanvas();
canvas.drawARGB(255,0,0,0);
canvas.drawBitmap(bitmap,new Rect(0,0,bw,bh),new Rect(0,0,bw,bh),null);
update(canvas);
}
}
}
public Bitmap bitmap;
public DrawThread thread;
public SurfaceHolder holder;
public BasicCanvas(Context context) {
super(context);
holder = getHolder();
holder.addCallback(this);
}
public Canvas getCanvas() {
return holder.lockCanvas();
}
public BasicCanvas update(Canvas canvas) {
holder.unlockCanvasAndPost(canvas);
return this;
}
public BasicCanvas createNew(int width,int height) {
bitmap = Bitmap.createBitmap(width,height,Bitmap.Config.ARGB_8888);
return this;
}
public BasicCanvas clear(int color) {
getPaintableCanvas().drawColor(color);
return this;
}
public Canvas getPaintableCanvas() {
return new Canvas(bitmap);
}
@Override
public void surfaceCreated(SurfaceHolder p1) {
bitmap = Bitmap.createBitmap(getWidth(),getHeight(),Bitmap.Config.ARGB_8888);
thread = new DrawThread();
thread.start();
}
@Override
public void surfaceChanged(SurfaceHolder p1, int p2, int p3, int p4) {
}
@Override
public void surfaceDestroyed(SurfaceHolder p1) {
}
}
用法
这是一个非常简单的类,把画图线程放了进去,只要调用getPaintableCanvas()就能获得一个Canvas对象,然后进行画图操作,最后什么都不用干,线程会自动把图画出来
提示
我继承BasicCanvas的时候出了问题,明明直接用BasicCanvas还是正常的