android 自定義屬性的使用

res/values/attr.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
	<declare-styleable name="MyView">
		<attr format="color" name="textColor"/>
		<attr format="dimension" name="textSize"/>
	</declare-styleable>
</resources>
           

src/com/android/spt/MyView.java

package com.android.spt;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;

import android.graphics.Paint;
import android.graphics.Paint.Style;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.view.View;

public class MyView extends View{

	private Paint mPaint;
	private Context mContext;
	private static final String mString = "Welcome to Mi's world";
	public MyView(Context context, AttributeSet attrs){
		super(context, attrs);
		
		mPaint = new Paint();
		TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.MyView);
		int textColor = a.getColor(R.styleable.MyView_textColor, 0xFFFFFFFF);
		float textSize = a.getDimension(R.styleable.MyView_textSize, 20);
		mPaint.setTextSize(textSize);
		mPaint.setColor(textColor);
		a.recycle();
	}
	@Override
	protected void onDraw(Canvas canvas){
		super.onDraw(canvas);
		mPaint.setStyle(Style.FILL);
		canvas.drawRect(new Rect(10,10,100,100),mPaint);
		canvas.drawText(mString, 10, 110, mPaint);	
	}
}
           

res/layout/main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 
	xmlns:android="http://schemas.android.com/apk/res/android"	
	    xmlns:spt="http://schemas.android.com/apk/res/com.android.spt"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >

    <com.android.spt.MyView
		android:layout_width="fill_parent"
		android:layout_height="fill_parent"
		spt:textSize="50px"
		spt:textColor="#FF00FF00"    
    />
</LinearLayout>
           

src/com/android/spt

package com.android.spt;

import android.app.Activity;
import android.os.Bundle;

public class MiDemoActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }
}