Android自訂控制項

package com.hzhi.customview;import android.content.Context;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.graphics.Path;import android.util.AttributeSet;import android.view.View;public class CustomView extends View{// 圖形類型int ss=0;// 建構函式public CustomView(Context context, AttributeSet attrs) {super(context, attrs);}// onDraw函數public void onDraw(Canvas c){super.onDraw(c);Paint p = new Paint();p.setColor(Color.GREEN);p.setStrokeWidth(10);switch (ss){// 畫圓形case 0:c.drawCircle(200, 200, 100, p);break;// 畫矩形case 1:c.drawRect(60, 90, 360, 300, p);break;// 畫三角形case 2:Path path = new Path();path.moveTo(80, 100);path.lineTo(420, 250);path.lineTo(80, 350);path.close();c.drawPath(path, p);break;default:break;}}public void changeStyle(){ss++;if (ss>2){ss=0;}}}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context=".MainActivity" >        <com.hzhi.customview.CustomView        android:id="@+id/cusView"android:layout_width="wrap_content"android:layout_height="wrap_content"    >    </com.hzhi.customview.CustomView></RelativeLayout>

package com.hzhi.customview;import android.os.Bundle;import android.os.Handler;import android.os.Message;import android.app.Activity;import android.view.View;public class MainActivity extends Activity {CustomView cv;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);cv = (CustomView) findViewById(R.id.cusView);        cv.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View v) {Message message = new Message();message.what = 1;myHandler.sendMessage(message);}});}    HandlermyHandler= new Handler() {//接收到訊息後處理public void handleMessage(Message msg){switch (msg.what){case 1:cv.changeStyle();cv.invalidate();break;}super.handleMessage(msg);}};}