drawview.java

来自「Google Android应用框架原理与程序设计 第三版(中文高清PDF)高焕」· Java 代码 · 共 32 行

package com.misoo.ex10;
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 {
    private Paint pa = new Paint();
    private boolean yn = false;
   
    public DrawView(Context context) {
        super(context);
     }
  @Override protected void onDraw(Canvas canvas) {
	     yn = !yn;
	     if(yn)pa.setColor(Color.GRAY);
	     else pa.setColor(Color.WHITE);
	     canvas.drawRect(10, 10, 100, 100, pa);
	     pa.setColor(Color.YELLOW);
	     if(yn)pa.setColor(Color.YELLOW);
	     else pa.setColor(Color.BLUE);
	     pa.setStrokeWidth(4);
         pa.setStrokeCap(Paint.Cap.ROUND);
         canvas.drawLine(10, 55, 100, 55, pa);
         canvas.drawLine(55, 10, 55, 100, pa);
         pa.setColor(Color.RED);
    	 canvas.drawRect(50, 50, 60, 60, pa);
     }
 }