android xml画一条线,如何在android中绘制一条线

这一个画在屏幕的左上角形成一个十字的2行：

DrawView.java

import android.content.Context;

import android.graphics.Canvas;

import android.graphics.Color;

import android.graphics.Paint;

import android.view.View;

public class DrawView extends View {

Paint paint = new Paint();

public DrawView(Context context) {

super(context);

paint.setColor(Color.BLACK);

}

@Override

public void onDraw(Canvas canvas) {

canvas.drawLine(0, 0, 20, 20, paint);

canvas.drawLine(20, 0, 0, 20, paint);

}

}

启动它的活动：

StartDraw.java

import android.app.Activity;

import android.graphics.Color;

import android.os.Bundle;

public class StartDraw extends Activity {

DrawView drawView;

@Override

public void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

drawView = new DrawView(this);

drawView.setBackgroundColor(Color.WHITE);

setContentView(drawView);

}

}