自定義ImageView控件，實現點擊高亮圖標

實現點擊高亮圖標，只使用一張資源圖。

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.PixelFormat;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.widget.ImageView;
/**
 * 自定義圖片控件，實現點擊變高亮(會覆蓋父容器的點擊事件)
 * @author zengxw 2013-08-22
 */
public class CustomImageView extends ImageView {
	
	/**保存當前容器原來設置的圖片*/
	private Drawable drawableSave;
	/**高亮圖片*/
	private Drawable drawableGrap;
	
	public CustomImageView(Context context) {
		super(context);
		setListener();
	}
	
	public CustomImageView(Context context, AttributeSet attrs) {
		super(context, attrs);
		setListener();
    }

	public CustomImageView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        setListener();
	}

	@Override
	public void setImageDrawable(Drawable drawable) {

		this.drawableSave = drawable;
		setSuperImageDrawable(drawable);
	}
	
	@Override
	public void setImageResource(int resId) {

		super.setImageResource(resId);
		this.drawableSave = this.getDrawable();
	}
	
	/**調用父類設置圖片方法*/
	private void setSuperImageDrawable(Drawable drawable)
	{
		super.setImageDrawable(drawable);
	}
	
	/**設置正常狀態*/
	public void setNormalState()
	{
		setSuperImageDrawable(drawableSave);
	}
	/**設置點擊狀態*/
	public void setClickedState()
	{
		setDrawableGrap();//生成點擊後圖片
		setSuperImageDrawable(drawableGrap);
	}
	
	/**
	 * 綁定事件
	 */
	private void setListener()
	{
		//鼠標事件
		this.setOnTouchListener(new OnTouchListener() {
			
			@Override
			public boolean onTouch(View v, MotionEvent event) {

			    switch (event.getAction()) 
			    {
			    	case MotionEvent.ACTION_DOWN:	//鼠標按下
			    		setClickedState();
			    		break;
			    	case MotionEvent.ACTION_UP:		//鼠標鬆開
			    		setNormalState();
			    		break;
			    	case MotionEvent.ACTION_CANCEL: //取消
			    		setNormalState();
			    		break;
			    	default :
			    		break;
			    }
				
				return true;
			}
		});
	}
	
	/**生成高亮圖片*/
	private void setDrawableGrap()
	{
		if(drawableGrap == null && drawableSave !=null)//是否已生成高亮圖片
		{
			/**Drawable轉Bitmap*/
	        int w = drawableSave.getIntrinsicWidth(); //取 drawable 的長寬  
	        int h = drawableSave.getIntrinsicHeight();  

	        Bitmap.Config config = drawableSave.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888 : Bitmap.Config.RGB_565; //取 drawable 的顏色格式  
	        Bitmap bitmap = Bitmap.createBitmap(w, h, config);//建立對應 bitmap  
	        Canvas canvas = new Canvas(bitmap);  //建立對應 bitmap 的畫布  
	        drawableSave.setBounds(0, 0, w, h);  
	        drawableSave.draw(canvas); //把 drawable 內容畫到畫布中  
	        
	        /**轉顏色*/
	        int array []  = new int[w*h];
	        int n =0;
	        int diff = 30;//差異亮度
	        for(int i=0;i<h;i++)
	        {
	            for(int j=0;j<w;j++) //從上往下掃描
	            { 
	                int color = bitmap.getPixel(j,i);
	                int r = Color.red(color) + diff;  
	                int g = Color.green(color) + diff;  
	                int b = Color.blue(color) + diff;
	                int a = Color.alpha(color);
		            
	                if(r > 255) r = 255;
	                if(g > 255) g = 255;
	                if(b > 255) b = 255;

	                color = Color.argb(a, r, g, b);
		            
	                array[n] = color;
	                n++;
	            }
	        }
	        bitmap = Bitmap.createBitmap(array,w,h,Bitmap.Config.ARGB_8888);
	        drawableGrap = new BitmapDrawable(getResources(), bitmap);
		}
	}
}