A Computer Engineer

Image uploading is necessary in any Android app now a days.
We can upload image to our server from the Android app. Here I used PHP at the server side to catch and save the image file.

Here we did it without using any kind of external library. So you can directly use it in your project without any hassle.

First we pick the image from the gallery. You can checkout my article, “Pick image from gallery before and after KITKAT version in Android” and get the path of the image file in the “path” variable.

Then use following code snippet to upload that image to the server.

String lineEnd = "\r\n";
String twoHyphens = "--";
String boundary = "*****";
try {
  connectURL = new URL("http://example.com/imageupload.php");
  HttpURLConnection conn = (HttpURLConnection) connectURL.openConnection();
  conn.setDoInput(true);
  conn.setDoOutput(true);
  conn.setUseCaches(false);
  conn.setRequestMethod("POST");
  conn.setRequestProperty("Connection", "Keep-Alive");
  conn.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + boundary);

  DataOutputStream dos = new DataOutputStream(conn.getOutputStream());
  dos.writeBytes(twoHyphens + boundary + lineEnd);

  HashMap<String, String> params = new HashMap<>();
  params.put("key", "value");	//post params that you want yo send
  StringBuilder result = new StringBuilder();
  for (Map.Entry<String, String> entry : params.entrySet()) {
    result.append("Content-Disposition: form-data; name=\"" + entry.getKey() + "\"" + lineEnd);
    result.append(lineEnd);
    result.append(entry.getValue());
    result.append(lineEnd);
    result.append(twoHyphens + boundary + lineEnd);
  }

  dos.writeBytes(result.toString());
  if (!String.valueOf("").equals(path)) {
    dos.writeBytes("Content-Disposition: form-data; name=\"" + "picture" + "\";filename=\"" + "picture.jpg" + "\"" + lineEnd);
    dos.writeBytes(lineEnd);
    fis = new FileInputStream(path);
    int bytesAvailable = fis.available();

    int maxBufferSize = 8192;
    int bufferSize = Math.min(bytesAvailable, maxBufferSize);
    byte[] buffer = new byte[bufferSize];

    int bytesRead = fis.read(buffer, 0, bufferSize);

    while (bytesRead > 0) {
      dos.write(buffer, 0, bufferSize);
      bytesAvailable = fis.available();
      bufferSize = Math.min(bytesAvailable, maxBufferSize);
      bytesRead = fis.read(buffer, 0, bufferSize);
    }
    dos.writeBytes(lineEnd);
    dos.writeBytes(twoHyphens + boundary + lineEnd);
    fis.close();
  }
  dos.flush();

  InputStream is = conn.getInputStream();

  int ch;

  StringBuffer b = new StringBuffer();
  while ((ch = is.read()) != -1) {
    b.append((char) ch);
  }
  json = b.toString();
  dos.close();
} catch (MalformedURLException ex) {
} catch (IOException ioe) {
}

Make sure that you call this code snippet inside of AsyncTask or Thread. Once you get the response from the server, your image has been uploaded to the server.

Now here is the code for PHP to move the uploaded to the same directory as php file.

    move_uploaded_file($_FILES['picture']['tmp_name'], $_FILES['picture']['name']);

And done! You can find your uploaded image in “images” directory on your server.