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Android图片缩放、圆角处理以及倒影特效代码

2011-10-17 20:44 本站整理 浏览(11)
public class ImageUtil {
	
	//缩放图片
	public static Bitmap zoomBitmap(Bitmap bitmap, int w, int h)
	{
		int width = bitmap.getWidth();
		int height = bitmap.getHeight();
		Matrix matrix = new Matrix();
		float scaleWidth = ((float)w/width);
		float scaleHeight = ((float)h/height);
		matrix.postScale(scaleHeight, scaleHeight);
		Bitmap newBmp = Bitmap.createBitmap(bitmap, 0, 0, width, height,matrix,true);
		return newBmp;
	}
    
	//Drawable 转换为Bitmap
	public static Bitmap drawableToBitmap(Drawable drawable)
	{
		int width = drawable.getIntrinsicWidth();
		int height = drawable.getIntrinsicHeight();
		Bitmap bitmap = Bitmap.createBitmap(width, height,
				drawable.getOpacity()!= PixelFormat.OPAQUE?Bitmap.Config.ARGB_8888
						:Bitmap.Config.RGB_565);
		Canvas canvas = new Canvas(bitmap);
		drawable.setBounds(0,0, width, height);
		drawable.draw(canvas);
		return bitmap;
	}
	
	//圆角处理
	public static Bitmap getRoundedCornerBitmap(Bitmap bitmap, float roundPx)
	{
		Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(),
				Config.ARGB_8888);
		Canvas canvas = new Canvas(output);
		
		final int color = 0xff424242;
		final Paint paint = new Paint();
		final Rect rect = new Rect(0,0, bitmap.getWidth(), bitmap.getHeight());
		final RectF rectF = new RectF(rect);
		
		paint.setAntiAlias(true);
		canvas.drawARGB(0, 0, 0, 0);
		paint.setColor(color);
		canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
		paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
		canvas.drawBitmap(bitmap, rect, rect, paint);
		
		return output;
	}
	
	//倒影图片处理
	public static Bitmap createReflectionImageWithOrigin(Bitmap bitmap)
	{
		final int reflectionGap = 4; //magic number?
		int width = bitmap.getWidth();
		int height = bitmap.getHeight();
		
		Matrix matrix = new Matrix();
		matrix.preScale(1, -1);
		
		Bitmap reflectionImage = Bitmap.createBitmap(bitmap,
				0, height/2 , width, height/2, matrix, false);
		Bitmap bitmapWithReflection = Bitmap.createBitmap(width, (height + height/2), Config.ARGB_8888);
		
		Canvas canvas = new Canvas(bitmapWithReflection);
		canvas.drawBitmap(bitmap, 0, 0, null);
		Paint deafalutPaint = new Paint();
		canvas.drawRect(0, height, width, height + reflectionGap, deafalutPaint);
		canvas.drawBitmap(reflectionImage, 0,height + reflectionGap, null);
		
		Paint paint = new Paint();
		LinearGradient shader = new LinearGradient(0,
				bitmap.getHeight(),
				0,
				bitmapWithReflection.getHeight()+reflectionGap, 
				0x70ffffff,
				0x00ffffff, 
				TileMode.CLAMP);
		paint.setShader(shader);
		//set the Transfer mode to be porter duff and destionation in
		paint.setXfermode(new PorterDuffXfermode(Mode.DST_IN));
		//Draw a rectangle using the paint with our linear gradient
		canvas.drawRect(0, height, width, bitmapWithReflection.getHeight() + reflectionGap, paint);
		
		return bitmapWithReflection;
	}
}