Android中自定义属性（attrs.xml，TypedArray）的使用【转】

该实例是在自定义View上使用自定义属性的。
先来看看源码：MyView.java

Code:
package com.adnroid.test; 
 
import com.adnroid.test.R; 
 
import android.content.Context; 
import android.content.res.TypedArray; 
import android.graphics.Canvas; 
import android.graphics.Color; 
import android.graphics.Paint; 
import android.graphics.Rect; 
import android.graphics.Paint.Style; 
import android.util.AttributeSet; 
import android.view.View; 
 
public class MyView extends View { 
    private Paint myPaint; 
    private static final String myString = "Welcome to our Zoon!"; 
 
    public MyView(Context context) { 
        super(context); 
        // TODO Auto-generated constructor stub 
     } 
     
    public MyView(Context context, AttributeSet attr) { 
        super(context, attr); 
         myPaint = new Paint(); 
         TypedArray a = context.obtainStyledAttributes(attr, R.styleable.myView);//TypedArray是一个数组容器 
        float textSize = a.getDimension(R.styleable.myView_textSize, 30);//防止在XML文件里没有定义，就加上了默认值30 
        int textColor = a.getColor(R.styleable.myView_textColor, 0xFFFFFFFF);//同上,这里的属性是:名字_属性名 
         myPaint.setTextSize(textSize); 
         myPaint.setColor(textColor); 
         a.recycle();//我的理解是：返回以前取回的属性，供以后使用。以前取回的可能就是textSize和textColor初始化的那段 
     } 
    @Override 
    protected void onDraw(Canvas canvas) { 
        // TODO Auto-generated method stub 
        super.onDraw(canvas); 
        //myPaint = new Paint(); 
         myPaint.setColor(Color.RED); 
         myPaint.setStyle(Style.FILL); 
         
         canvas.drawRect(new Rect(10,10,100,100), myPaint); 
         myPaint.setColor(Color.WHITE); 
         canvas.drawText(myString, 10, 100, myPaint); 
     } 
 
} 
attrs.xml

Code:
<?xml version="1.0" encoding="utf-8"?> 
<resources> 
    <declare-styleable name="myView"> 
        <attr name="textColor" format="color"/> 
        <attr name="textSize" format="dimension"/> 
    </declare-styleable> 
</resources> 
main.xml

Code:
<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:test="http://schemas.android.com/apk/res/com.adnroid.test" 
    android:orientation="vertical" 
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent" 
    > 
<TextView   
    android:layout_width="fill_parent"  
    android:layout_height="wrap_content"  
    android:text="@string/hello" 
    /> 
<com.adnroid.test.MyView 
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent" 
    test:textSize="10px" 
    test:textColor="#fff" 
    /> 
</LinearLayout> 
最终的效果