来自Android中longblob的位图

Question

I have some images stored as longblob s in a remote MySQL database and I need to retrieve them for my Android application and display as a Bitmap . I have a PHP script setup to parse SQL queries to/from the Android application.

What I have tried: I tried to get a String as below of the longblob field and then used getBytes() on it. But apparently, it isn't working. If I display the String, a huge number of characters (readable as well as unreadable) are displayed. So the problem is with encoding or converting from String to byte[] (I think).

StringBuilder strStream = new StringBuilder();
BufferedReader reader = new BufferedReader(new InputStreamReader(httpEntity.getContent()), 8);

String line = null;
while((line = reader.readLine()) != null) strStream.append(line);

Bitmap bitmap = BitmapFactory.decodeByteArray(strStream.toString().getBytes(), 0, strStream.length());

What I Need: Is there any way to create a Bitmap from a remote longblob stored in a MySQL database which I connect from Android using a custom PHP script? I'm perfectly sure the script is working correctly and my code is 100% working up to the variable httpEntity . I can even get the String and its the correct value. The only problem is, I can't get a Bitmap .

Thanks.

Answer 1

The simpler, the better :) PHP can output a blob from a database

header('Content-Type: image/png');
echo $result['blob'];

When you request this script with a web browser, you'll see a PNG image. Then the Android part

InputStream in = new URL("http://img.io/read.php").openStream();
Bitmap bmp = BitmapFactory.decodeStream(in);
in.close();

There's no need to pass through Strings here... Strings in Java are not simply byte arrays. They carry semantics, so the byte array is always coupled with an encoding scheme (which defaults to UTF-16LE)