I am writing a little picture frame app for android that is using opengl for part of the UI. This portion needs to get images from flickr and load them into a texture. The code I have below is functional most of the time, but it has a Thread.sleep() kludge in between getting the input stream from the connection and the bitmap factory decoding the stream:
URL url = new URL("http://farm5.static.flickr.com/4132/5168797476_7a85deb2be_b.jpg");
URLConnection con = url.openConnection();
InputStream is = con.getInputStream();
Thread.sleep(250); //What am I actually waiting for?
sourc开发者_开发知识库eBitmap = BitmapFactory.decodeStream(is);
How do I get around using the sleep() method in favor of something that makes logical sense?
I am testing on a samsung galaxy tab not in the emulator
I think you should implement AsyncTask
. Refer this: http://developer.android.com/resources/articles/painless-threading.html
public void onClick(View v) {
new DownloadImageTask().execute("http://example.com/image.png");
}
private class DownloadImageTask extends AsyncTask<string, void,="" bitmap=""> {
protected Bitmap doInBackground(String... urls) {
return loadImageFromNetwork(urls[0]);
}
protected void onPostExecute(Bitmap result) {
mImageView.setImageBitmap(result);
}
}
I hope it helps you !!
This seems less than ideal, but if you read the stream byte by byte into a buffer and then pass the byte array to the BitmapFactory it works correctly.
URL url = new URL("http://farm5.static.flickr.com/4132/5168797476_7a85deb2be_b.jpg");
URLConnection con = url.openConnection();
con.connect();
int fileLength = con.getContentLength();
InputStream is = con.getInputStream();
byte[] bytes = new byte[fileLength];
for(int i=0;i<fileLength;i++) {
bytes[i] = (byte)is.read();
}
sourceBitmap = BitmapFactory.decodeByteArray(bytes, 0, fileLength);
I tried reading the bytes into the buffer all at once with is.read(bytes, 0, fileLength) but it did not reliably fill the buffer completely unless I waited a moment before calling the read. Is it possible that android implementation of InputStream's read method is flawed causing the BitmapFactory's decodeStream method to fail due to incomplete data?
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