自定义控件之带图片的TextView（带命名空间）

Java代码

package com.myself.custom.view;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.widget.TextView;

import com.myself.custom.activity.R;

/**
 * @文件名 IconTextView.java
 * @类说明 (带图片的TextView)	
 * @作者 xxxx
 * @版本 v_1.0
 * @创建时间 2014-3-19 下午12:06:50
 */
public class IconTextView extends TextView {
	private final String ATTR_ICON_SRC = "iconSrc";
	private final String NAMESPACE = "http://www.myself.com";
	private Bitmap bitMap;
	public IconTextView(Context context, AttributeSet attrs) {
		super(context, attrs);
		int resouceId = attrs.getAttributeResourceValue(NAMESPACE, ATTR_ICON_SRC, R.drawable.ic_launcher);
		bitMap = BitmapFactory.decodeResource(getResources(), resouceId);
	}
	
	@Override
	protected void onDraw(Canvas canvas) {
		if(bitMap != null){
			//源 将图像截取部分内容，这里为整张图像
			Rect src = new Rect();
			src.top = 0;
			src.left = 0;
			src.right = bitMap.getWidth();
			src.bottom = bitMap.getHeight();
			
			int textHeight =  (int) getTextSize();
			Rect target = new Rect();
			target.left = 0;
			//  计算图像复制到目录区域的纵坐标。由于TextView中文本内容并不是从最顶端开始绘制的，因此，需要重新计算绘制图像的纵坐标
			target.top = (int) ((getMeasuredHeight() - getTextSize()) / 2) + 1;
			target.bottom = target.top + textHeight;
			//  为了保证图像不变形，需要根据图像高度重新计算图像的宽度
			target.right = (int) (textHeight * (bitMap.getWidth() / (float) bitMap
					.getHeight())); 
			canvas.drawBitmap(bitMap, src, target, getPaint());
			canvas.translate(target.right + 2, 0);
		}
		super.onDraw(canvas);
	}
}

           

xml引用方式

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:myself="http://www.myself.com"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    >
  <com.myself.custom.view.IconTextView
   	android:layout_width="match_parent"
   	android:layout_height="wrap_content"
   	myself:iconSrc="@drawable/ic_menu_shuffle"
   	android:text="我是textView"
   	android:textSize="30sp"
   />
</LinearLayout>