Android开发入门-画图
创建自定义View
1.建立Myview.java
1 //MyView.java
2 package com.droidhen.test.test_2;
3
4 import android.content.Context;
5 import android.graphics.Canvas;
6 import android.graphics.Color;
7 import android.graphics.Paint;
8 import android.graphics.RectF;
9 import android.util.AttributeSet;
10 import android.view.View;
11
12 public class MyView extends View{
13 public MyView(Context context, AttributeSet attrs){
14 super(context, attrs);
15 }
16 protected void onDraw(Canvas canvas){
17 super.onDraw(canvas);
18 canvas.drawColor(Color.BLACK);
19 Paint paint = new Paint();
20 paint.setAntiAlias(true);
21 paint.setColor(Color.RED);
22 canvas.drawRect(10,10,110,110, paint);
23 canvas.drawText("这是字符串",10,130, paint);
24 RectF rf1 = new RectF(10,130,110,230);
25 canvas.drawArc(rf1, 0, 45, true, paint);
26 canvas.drawLine(150, 10, 250, 110, paint);
27 RectF rf2 = new RectF(150,130,250,230);
28 canvas.drawOval(rf2, paint);
29 }
30 }
2.在main.xml中加入自定义的View
1 <?xml version="1.0" encoding="utf-8"?>
2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
3 android:orientation="vertical"
4 android:layout_width="fill_parent"
5 android:layout_height="fill_parent"
6 >
7 <com.droidhen.test.test_2.MyView
8 android:id="@+id/myView"
9 android:layout_width="fill_parent"
10 android:layout_height="fill_parent"
11 />
12 </LinearLayout>
3.在main.java里面
1 package com.droidhen.test.test_2;
2
3 import android.app.Activity;
4 import android.os.Bundle;
5
6 public class test2 extends Activity {
7 /** Called when the activity is first created. */
8 @Override
9 public void onCreate(Bundle savedInstanceState) {
10 super.onCreate(savedInstanceState);
11 setContentView(R.layout.main);
12 }
13 }
