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in Technique[技术] by (71.8m points)

Best method to download image from url in Android

I'm using below method to download single image from url

public static Bitmap getBitmap(String url) {
    try {
        InputStream is = (InputStream) new URL(url).getContent();
        Bitmap d = BitmapFactory.decodeStream(is);
        is.close();
        return d;
    } catch (Exception e) {
        return null;
    }
}

Sometimes I get an outofmemory exception.

I am unable to catch outofmemory exception. The app will close. How to prevent this?

Is there a better method for downloading images that is also faster?

Question&Answers:os

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1 Answer

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by (71.8m points)

Try to use this:

public Bitmap getBitmapFromURL(String src) {
    try {
        java.net.URL url = new java.net.URL(src);
        HttpURLConnection connection = (HttpURLConnection) url
                .openConnection();
        connection.setDoInput(true);
        connection.connect();
        InputStream input = connection.getInputStream();
        Bitmap myBitmap = BitmapFactory.decodeStream(input);
        return myBitmap;
    } catch (IOException e) {
        e.printStackTrace();
        return null;
    }
}

And for OutOfMemory issue:

 public Bitmap getResizedBitmap(Bitmap bm, int newHeight, int newWidth) {
    int width = bm.getWidth();
    int height = bm.getHeight();
    float scaleWidth = ((float) newWidth) / width;
    float scaleHeight = ((float) newHeight) / height;
    // CREATE A MATRIX FOR THE MANIPULATION
    Matrix matrix = new Matrix();
    // RESIZE THE BIT MAP
    matrix.postScale(scaleWidth, scaleHeight);

    // "RECREATE" THE NEW BITMAP
    Bitmap resizedBitmap = Bitmap.createBitmap(bm, 0, 0, width, height,
            matrix, false);

    return resizedBitmap;
}

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