游戏开发2_01

package wyf.ytl;
import android.content.Context;//引入相关的包
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.view.View;
public class MyView extends View{
public MyView(Context context, AttributeSet attrs) {//构造器
super(context, attrs);
}
protected void onDraw(Canvas canvas) {//重写的绘制方法
super.onDraw(canvas);
canvas.drawColor(Color.BLACK);//绘制黑色背景
Paint paint = new Paint();//创建画笔
paint.setColor(Color.WHITE);//设置画笔颜色为红色
canvas.drawRect(10, 10, 110, 110, paint);//绘制矩形
canvas.drawText("这是字符串", 10, 130, paint);//字符串，以字符串下面为基准
RectF rf1 = new RectF(10, 130, 110, 230);//定义一个矩形
canvas.drawArc(rf1, 0, 45, true, paint);//画弧，顺时针
canvas.drawLine(150, 10, 250, 110, paint);//画线
RectF rf2 = new RectF(150, 130, 250, 230);//定义一个矩形
canvas.drawOval(rf2, paint);//画圆
}
}



package wyf.ytl;

import android.app.Activity;
import android.os.Bundle;

public class Sample_2_7 extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }
}


<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<wyf.ytl.MyView 
android:id="@+id/myView"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    />
</LinearLayout>

在xml文件中定义view  需要使用全称类名