图片Url保存为位图并进行缩放操作

1.通过传入图片url获取位图方法:

public Bitmap returnBitMap(String url) {
		URL myFileUrl = null;
		Bitmap bitmap = null;
		try {
			myFileUrl = new URL(url);
		} catch (MalformedURLException e) {
			e.printStackTrace();
		}
		try {
			HttpURLConnection conn = (HttpURLConnection) myFileUrl
					.openConnection();
			conn.setDoInput(true);
			conn.connect();
			InputStream is = conn.getInputStream();
			bitmap = BitmapFactory.decodeStream(is);
			is.close();
		} catch (IOException e) {
			e.printStackTrace();
		}
		Log.v(tag, bitmap.toString());

		return bitmap;
	}

2.通过传入位图,新的宽.高比进行位图的缩放操作:

public static Drawable resizeImage(Bitmap bitmap, int w, int h) {

		// load the origial Bitmap
		Bitmap BitmapOrg = bitmap;

		int width = BitmapOrg.getWidth();
		int height = BitmapOrg.getHeight();
		int newWidth = w;
		int newHeight = h;

		Log.v(tag, String.valueOf(width));
		Log.v(tag, String.valueOf(height));

		Log.v(tag, String.valueOf(newWidth));
		Log.v(tag, String.valueOf(newHeight));

		// calculate the scale
		float scaleWidth = ((float) newWidth) / width;
		float scaleHeight = ((float) newHeight) / height;

		// create a matrix for the manipulation
		Matrix matrix = new Matrix();
		// resize the Bitmap
		matrix.postScale(scaleWidth, scaleHeight);
		// if you want to rotate the Bitmap
		// matrix.postRotate(45);

		// recreate the new Bitmap
		Bitmap resizedBitmap = Bitmap.createBitmap(BitmapOrg, 0, 0, width,
				height, matrix, true);

		// make a Drawable from Bitmap to allow to set the Bitmap
		// to the ImageView, ImageButton or what ever
		return new BitmapDrawable(resizedBitmap);

	}