Develop Reference

Getting image download links from owncloud server

there is not much information out there for the newbies to owncloud.. not even here in Stack Overflow, a little background on what im trying to achieve is:
-Already managed to sync my project to the owncloud library via gradlle.
- The provided examples are not of much help for me you will see why.
I use this library https://github.com/bumptech/glide to stream images URLs to some imageviews in my app, as i was on a web server I had no problem but now that I moved to owncloud, I can do the same if i provide my app with the "download link" from the stored images.
That said, what I need is to some how be able to select the owncloud stored images(access the shared folder and download) by name and or read the download link from where ever is stored..
here is the use the glide library on my project
String url = null;
if (plato.getFoto_movil().equals("churrasco.jpg"))
{
url = "http://192.168.0.20/owncloud/index.php/s/EqX7LxLpUeBCzF4/download";
}
if (plato.getFoto_movil().equals("pizza.jpg"))
{
url = "http://192.168.0.20/owncloud/index.php/s/VGQJh6ii36PLGsN/download";
}
if (plato.getFoto_movil().equals("torta_chocolate.jpg"))
{
url = "http://192.168.0.20/owncloud/index.php/s/K0TaHRMPuMrs0Fx/download";
}
Glide.with(mContext).load(url).into(imageView);
which is sad because I had to manually get those URLs from my browser and it does not work with the newly added images from any othere device, so I need to be able to get any new image and show it too.
I have the library installed 100% and implemented but
private void startDownload(String filePath, File targetDirectory) {
DownloadRemoteFileOperation downloadOperation = new DownloadRemoteFileOperation(filePath, targetDirectory.getAbsolutePath());
downloadOperation.addDatatransferProgressListener((OnDatatransferProgressListener) mContext);
downloadOperation.execute( mClient, (OnRemoteOperationListener) mContext, mHandler);
}
#Override
public void onTransferProgress(long l, long l1, long l2, String s) {
mHandler.post( new Runnable() {
#Override
public void run() {
// do your UI updates about progress here
}
});
}
#Override
public void onRemoteOperationFinish(RemoteOperation remoteOperation, RemoteOperationResult remoteOperationResult) {
if (remoteOperation instanceof DownloadRemoteFileOperation) {
if (remoteOperationResult.isSuccess()) {
}
}
}
got those and
got also this two
mClient = OwnCloudClientFactory.createOwnCloudClient(serverUri,mContext,true);
mClient.setCredentials(OwnCloudCredentialsFactory.newBasicCredentials(username,password));
then I call the method
startDownload(plato.getFoto_movil(),downloadfolder);
the app crashes here when I call the startdowonload method
with the error java.lang.ClassCastException: com.eidotab.eidotab.MainActivity cannot be cast to com.owncloud.android.lib.common.network.OnDatatransferProgressListener
another relevant information is that im implementing the ownclod methods to
the viewholder of a recyclerview
public class VH extends RecyclerView.ViewHolder implements OnRemoteOperationListener, OnDatatransferProgressListener
but I could change to the main activity if needed, probably make it work from there but even if it does have success, don´t know where or how to get the download links, like I said, I need the download link from every image stored in the server..
is this possible?
thanks in advance

I changed the implementation of the owncloud library to the main activity as suggested (and was the logical move) and everything went smooth.. worked at first try, I knew it was going to, the thing is that I didnt want to store the images on the device memory, I want to capture the download links which was my main concern but for now it is working since im streaming the images directly from the local sd to the imageview and that should give me some more time to investigate further in the matter whats the thing with the URLS...
Thanks cricket for your comments

Libgdx,change pitch in Music

I want to implement a cool effect, when there is an explosion the music gets slightly slower for a moment.
The Music class of libgdx doesn't allow changing the pitch of the sound, I tried using the Sound class instead of the Music to play my music but its very slow at loading the files ( 5 sec for a 5 mb file, on Desktop! ).
So, the question is if there is a way to workaround this, or if there is an external library, that works both on desktop and android and can work along with libgdx.

After some searching I found a way by editing the libgdx source code.
You need to use the AudioDevice object to play your music sample by sample ,to do that you need to include the audio-extension of libgdx.
We gonna edit the libgdx source code so you need to download it and replace the gdx.jar , gdx-backend-android.jar and gdx-backend-lwjgl.jar with the correct libgdx projects(they have the same name without the jar extension)
1)Edit the AudioDevice.java inside com.badlogic.gdx.audio package of the gdx project
add the following code inside the interface
public void setSpeed(float val);
2)Edit the AndroidAudioDevice.java inside com.badlogic.gdx.backends.android package of the gdx-backend-android project
The Android side of the AudioDevice class relies on the AudioTrack class of the Android sdk ,this class has a setPlaybackRate(..) method.
add the following code inside the class
#Override
public void setSpeed (float speed) {
track.setPlaybackRate((int)(track.getSampleRate()*speed));
}
3)Edit the OpenALAudioDevice.java inside com.badlogic.gdx.backends.lwjgl.audio package of the gdx-backend-lwjgl project
The Desktop side of the AudioDevice relies on OpenAL (the opengl of audio) which has a handy set pitch method
add the following inside the class
#Override
public void setSpeed (float speed) {
alSourcef(sourceID, AL_PITCH, speed);
}
4)Play the audio
Here is the code for loading and playing the sound file
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.audio.AudioDevice;
import com.badlogic.gdx.audio.io.Mpg123Decoder;
import com.badlogic.gdx.files.FileHandle;
public class MusicBeat {
static short[] samples = new short[2048];
Mpg123Decoder decoder;
AudioDevice device;
static FileHandle externalFile;
public boolean playing=true;
public MusicBeat(String name )
{
FileHandle file=Gdx.files.internal(name);
FileHandle external=Gdx.files.external("myappname/"+name);
if(!external.exists())file.copyTo(external); //copy the file to the external storage only if it doesnt exists yet
decoder = new Mpg123Decoder(external);
device = Gdx.audio.newAudioDevice(decoder.getRate(),decoder.getChannels() == 1 ? true : false);
playing=false;
externalFile=file;
}
void play()
{
playing=true;
Thread playbackThread = new Thread(new Runnable() {
#Override
public synchronized void run() {
int readSamples = 0;
while ( playing) {
if(decoder!=null){
if((readSamples = decoder.readSamples(samples, 0,samples.length))<=0){
decoder.dispose();
decoder = new Mpg123Decoder(externalFile);
playing=false;
}
device.writeSamples(samples, 0, readSamples);
}
}
}
});
playbackThread.setDaemon(true);
playbackThread.start();
}
public void stop(){
playing=false;
decoder.dispose();
}
public void setVolume(float vol){
device.setVolume(vol);
}
public void setSpeed(float speed){
device.setSpeed(speed);
}
}
Where to get the audio extension?(required for the AudioDevice)
The audio extension seems to have been deprecated and the jars cant be found easily, I have uploaded them here, its an old version but should work just fine.
Easier way?
If your game is only intent to run on desktop ,the Music class of libgdx on desktop relies again on OpenAL which gives as the power to play with the pitch ,so you just need to edit the Music interface(OpenALMusic on desktop) instead of the AudioDevice and get out the whole play sample by sample thing out of the equation,unfortunately as dawez said the Music class on android relies on MediaPlayer which is not giving us the pitch change option.
Conclusion :This method doesnt seem nice to me ,If your game really needs the pitch thing and it doesn't makes sense without it then go with it ,otherwise its just too much effort for such a small detail .

It seems that you cannot change the pitch of Music in Android.
To play music in libgdx you refer to the Interface Music:
public interface Music extends Disposable {
This is implemented by
package com.badlogic.gdx.backends.android;
public class AndroidMusic implements Music, MediaPlayer.OnCompletionListener {
private MediaPlayer player;
You are interested in the player object. That is of type MediaPlayer
package android.media;
public class MediaPlayer {
So now it boils down to the question if android is able to support pitching on the MediaPlayer class. Short answer no, long answer:Speed Control of MediaPlayer in Android
A workaround that you can do is to use a SoundPool even if that is slow, the loading can be started while the user is the loading screen. Otherwise you can try can split the music files in chunks and load them as you go still using a SoundPool. So you would do something like a lazy loading when the current part is coming to its end.
If you manage to find a suitable a solution, please post the relative code!

With the release of Android 6.0 (API level 23), "PlaybackParams" can be added to the MediaPlayer. These include playback speed and pitch among others.

BluetoothHeadset - Can't access public method

On the following page I am browsing the android source code for the BluetoothHeadset object:
http://androidxref.com/4.2.2_r1/xref/frameworks/base/core/java/android/bluetooth/BluetoothHeadset.java
Now in my code after getting the BluetoothHeadset object, I cannot access the method:
public void phoneStateChanged(args...)
Does anyone knows why it's not accessible? I tried using reflection but without effect...
My code:
protected BluetoothProfile.ServiceListener headsetProfileListener = new BluetoothProfile.ServiceListener()
{
#Override
public void onServiceConnected(int profile, BluetoothProfile proxy)
{
// mBluetoothHeadset is just a head set profile,
// it does not represent a head set device.
bluetoothHeadset = (BluetoothHeadset) proxy;
bluetoothHeadset.phoneStateChanged(...); //this method doesnt get autocompleted or recognised
}
};
EDIT: I know the method isn't mentioned in the android docs, but it probably is in the source code and maybe is made private, also I run a Cyanogen rom where the function is declared...
It's an app to experiment around with bluetooth and sending notifications...
Also I'm new to using reflection, so maybe the issue lies here:
bluetoothHeadset.getClass().getDeclaredMethod("phoneStateChanged", null);

That function isn't part of the API here: http://developer.android.com/reference/android/bluetooth/BluetoothHeadset.html
If its not part of the published API, you can't count on it. It may not actually be in the version of the framework you're using.

How to know when MediaRecorder has finished writing data to file

We're using MediaRecorder to record video to a file on the external storage using setOutputFile() before doing the actual recording.
Everything works fine, but the main issue is that as soon as the recording is done, we want to start playing the recorded video back in a VideoView.
How to know when the file is ready to be read and played back?

The FileObserver class suits your needs perfectly. Here is the documentation. It's easy to use. When a observed file is closed after writing, the onEvent callback is called with CLOSE_WRITE as the parameter.
MyFileObserver fb = new MyFileObserver(mediaFile_path, FileObserver.CLOSE_WRITE);
fb.startWatching();
class MyFileObserver extends FileObserver {
public MyFileObserver (String path, int mask) {
super(path, mask);
}
public void onEvent(int event, String path) {
// start playing
}
}
Don't forget to call stopWatching().

We solved similar problem with the following algo:
while (file not complete)
sleep for 1 sec
read the fourth byte of the file
if it is not 0 (contains 'f' of the 'ftyp' header) then
file is complete, break
The key point is that MediaRecorder writes the ftyp box at the very last moment. If it is in place, then the file is complete.

In my tests irrespective of the size of the recording mediaRecorder.stop() is a blocking method that only returns after the file has been completely written and closed by the media recorder.
So JPMs answer is actually correct.
You can verify this by calling File.length() immediately after stop(). You will find that the output file length is the final length of the file at this point. In other words media recorder does not write anything further to the file after stop() has returned.

I haven't tried this myself but this might work:
public void release () Since: API Level 1
Releases resources associated with this MediaRecorder object. It is
good practice to call this method when you're done using the
MediaRecorder.
If it does what it says, then I guess if you call this and after this method returns you know the file is ready.

Apparently there is no way to detect when the recording has stopped in Media player, but there is a stop() that you can override if you create a custom class that implements MediaRecorder. here I would do something like this:
public class MyRecorder implements MediaRecorder {
public boolean stopped;
.... implement all the methods that MediaRecorder has making
sure to call super for each method.
#Override
public void myStop() {
this.stopped = true;
super.stop();
}
}
Then you can access the boolean to see if it has stopped recording.

A dirty way would be to check the lastModified() value of the File and open the VideoView if the File wasn't modified for 2 seconds.

LVL licensing in a Live Wallpaper?

Has anybody had success integrating the Licensing Verification Library (LVL) with a Live Wallpaper? If it were just running an Activity, it'd be crystal clear to just extend my Activity from the Licensing Activity, which in turn extends Activity. But Live Wallpapers are a Service, and I'm not sure how the two are intended to interact.
I'm using code derived from this: http://www.droidforums.net/forum/android-app-developers/69899-market-license-easy-implementation-protect-your-apps.html which seems to be the code that nearly everything I can find on the web refers to.
I notice that wallpaper settings are an activity, and I have those working properly, but for some reason I can't grok the Licensing stuff...

It's actually really quite simple, you don't need to use any Activity class to implement licensing into a WallpaperService.
Make sure you've followed the directions carefully at http://developer.android.com/guide/publishing/licensing.html
Here's how I did it:
Your extended Engine class should include something similar to the following... (code not essential to your question has been removed)
class startYourEngines extends Engine {
public startYourEngines() {
super();
licenseStatus(); //custom license check method (for modularity)
//the rest of your engine would go here
}
public void onDestroy() {
super.onDestroy();
licenseChecker.onDestroy(); //we call this to close IPC connections
}
//prep work
private static final String BASE64_PUBLIC_KEY = //OMITTED//;
private LicenseCheckerCallback licenseCallback;
private LicenseChecker licenseChecker;
private byte[] salt = "rAnd0mStr!ng".getBytes();
private AESObfuscator aes;
private String deviceId;
//our custom license check method
private void licenseStatus() {
deviceId = Secure.getString(getContentResolver(), Secure.ANDROID_ID);
aes = new AESObfuscator(salt, getPackageName(), deviceId);
licenseCallback = new licenseVerification();
licenseChecker = new LicenseChecker(context, new ServerManagedPolicy(context, aes), BASE64_PUBLIC_KEY);
licenseChecker.checkAccess(licenseCallback);
}
//our callback method
private class licenseVerification implements LicenseCheckerCallback {
#Override
public void allow() {
//allow full app use
}
#Override
public void dontAllow() {
//prevent or limit app use
}
#Override
public void applicationError(ApplicationErrorCode errorCode) {
//error handling here
}
}
}
Licensing on the Android platform was created with versatility in mind. Just be sure to read through the documentation, and you shouldn't have any issues.

I have only written applications that start activities, but looking at my source code, it seems that the only reason that you would have to have an Activity do the license check is to show dialogs.
In all of the examples available on line, the LicenseCheckerCallback implementation always shows a dialog in the allow() and dontAllow() methods. Why not just show a toast in dontAllow() and exit your wallpaper service (call stopSelf(YourService.this))?
Let me know if you want more information, because I dont think you are limited to only using an activity for license checking. As an aside, make sure that you dont keep whole strings, etc in your app or in the preferences. Anyone with root access can access your preferences and if your app is decompiled, your strings are visible...

I think I've actually got it working now. I'm extending LicenseCheckActivity to my own Activity class that I'm calling in the manifest file with the usual MAIN action and LAUNCH category. I instantiate my class, do the license check, and then either allow the wallpaper to function or not based on that result (though the best way to do that is still something I need to sort out).
It almost seems too easy that I think I must be missing something. I'd appreciate anybody with experience with selling a licensed live wallpaper on the Android Market to share whatever wisdom they care to.