Question

I’m setting an ImageView using setImageBitmap with an external image url. I would like to save the image so it can be used later on even if there is no internet connection. Where and how can I save it?

Answer 1

You have to save it in SD card or in your package data, because on runtime you only have access to these. To do that this is a good example

URL url = new URL ("file://some/path/anImage.png");
InputStream input = url.openStream();
try {
//The sdcard directory e.g. '/sdcard' can be used directly, or 
//more safely abstracted with getExternalStorageDirectory()
File storagePath = Environment.getExternalStorageDirectory();
OutputStream output = new FileOutputStream (storagePath + "/myImage.png");
try {
    byte[] buffer = new byte[aReasonableSize];
    int bytesRead = 0;
    while ((bytesRead = input.read(buffer, 0, buffer.length)) >= 0) {
        output.write(buffer, 0, bytesRead);
    }
} finally {
    output.close();
}
} finally {
input.close();
}

Source : How do I transfer an image from its URL to the SD card?