怎么用Android画一个正方形

[依旧Smile]

快点啊，在线等

[l408109070317]

在view的onDraw(Canvas canvas))函数里画，用 canvas.drawRect(r, paint)函数
r是Rect类型的

[依旧Smile]

package smile.FristOne;

import android.app.Activity;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Rect;
import android.os.Bundle;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.Button;

public class FristOne extends Activity {
/** Called when the activity is first created. */
SurfaceView sfv;
SurfaceHolder shv;
Button button;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
button=(Button)findViewById(R.id.button);
sfv = (SurfaceView)findViewById(R.id.SurfaceView01);
// button.setOnClickListener(new ButtonListener());
Canvas canvas = shv.lockCanvas();
Rect rect = new Rect(0,0,10,10);
Paint mypaint = new Paint();
mypaint.setColor(Color.BLUE);
canvas.clipRect(rect);
canvas.drawRect(rect, mypaint);
shv.unlockCanvasAndPost(canvas);
}

}
我是个菜鸟 这么写一定错了，帮忙看看哪里错了，应该怎么改啊？谢谢了！

[hijovi]

public class CanvasDemoActivity extends Activity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);

		setContentView(new CustomView1(this));

	}


	class CustomView1 extends View{

		Paint paint;

		public CustomView1(Context context) {
			super(context);
			paint = new Paint(); 
			paint.setColor(Color.YELLOW);
			paint.setStrokeJoin(Paint.Join.ROUND);
	        paint.setStrokeCap(Paint.Cap.ROUND);
	        paint.setStrokeWidth(3);
		}

		
		@Override
		protected void onDraw(Canvas canvas) {
                  
                //请在这里进行绘制
                        RectF rect = new RectF(50, 50, 200, 200);

			canvas.drawRect(rect, paint);

		}

	}

}

[念茜]

[Quote=引用 3 楼 hijovi 的回复:]

Java code

public class CanvasDemoActivity extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);

setContentV……
[/Quote]

顶3L

[依旧Smile]

paint.setStrokeJoin(Paint.Join.ROUND);
paint.setStrokeCap(Paint.Cap.ROUND);
这两句什么意思啊？

[依旧Smile]

我想问一下 3楼 要加Button控件的话 setContentView(new CustomView1(this));

这个不应该是R.main.Button吗？他们俩冲突吗？
怎么办？