I use EasyVideoPlayer library in my Android application, when the video appears doesn't see the video, I only view a black screen. But when I rotate the screen to portrait or landscape it works perfectly. I don´t know what is the problem...
My code:
EasyVideoPlayer vVideo = (EasyVideoPlayer) findViewById(R.id.vVideo);
vVideo.setCallback(this);
vVideo.setSource(Uri.parse(url));
vVideo.setAutoPlay(true);
vVideo.start();
Thanks in advance
When you rotate the device, unless you have orientation locked which does not sound like it is there case, Android will kill your activity and restart it.
The reason it does this is to allow the activity be recreated with the correct resources for the new orientation - in fact it does the same thing for other configuration changes also, such as a language change.
So, take a look at the code that gets called when your activity is destroyed and recreated, in particular 'onCreate', 'onResume' etc - you will most likely find that something is being done here which allows the video to play correctly but which is missing when you hit the 'play' button normally.
Related
Does anybody know how to cope the problem?
Using the android.app.Activity#setRequestedOrientation(SCREEN_ORIENTATION_LANDSCAPE) method almost always causes the showing a black screen for a split second during the rotation.
But if I rotate the smartphone itself, then the black screen never appears.
How to get rid of the black screen? Is it the Android issue of the setRequestedOrientation() method, or I do something wrong?
EDIT: AFAIK the black screen with setRequestedOrientation() call could happen if we have quite heavy layout, when it takes some more time to initialize it in the UI thread. If you try to call setRequestedOrientation() for instance in a "Hello World!" app with a light layout, you won't see the black screen. So, the loading on the UI thread can be the cause of the black screen when you rotate with setRequestedOrientation(). But, in other hand why it never appears when I rotate the screen changing the phone orientation?
The only solution I've found.
Consider I want to turn screen to landscape and what do I do:
I remove the root Fragment with heavy stuff from the Activity I want to rotate.
Inside the Activity I want to rotate I open an empty white Activity for a moment to cover the black screen. The Activity is calling setRequestedOrientation(SCREEN_ORIENTATION_LANDSCAPE) in its onCreate callback and closes itself after the timeout = 500 ms. I open/close the Activity with fade-in/fade-out animation.
Inside the Activity I want to rotate I call setRequestedOrientation(SCREEN_ORIENTATION_LANDSCAPE) post delayed with 100 ms. This starts the rotation.
After the rotation complete, in the onCreate I add the removed Fragment back.
That's it. Rotation to landscape is finished and the black screen was completely covered.
Edited:
I had the same problem. In older versions of android, if the content of the layout is heavy (if it contains high resolution image, etc.), the running activity is trying to re-create the layout to change the orientation but can't achieve this.
As a solution, we can create 2 different layout resources as portrait and landscape, specifying which one we will use and making it easier for the android.
My application is bitmap intensive, with pixel-exact layout (it's a sort of game, actually, and it's pretty hard to avoid this pixel-based coordinates).
What I wanted to do is to perform some layout calculations and bitmap pre-scaling in my onCrete - I use well known API - getWindowManager().getDefaultDisplay().getSize() - to retrieve the screen size and do my calculations.
However, I've just hit an unexpected problem. My activity is configured as landscape only, but if I start my application on emulator and onCreate() is called while the emulator is locked, the screen size returned by getSize() indicates portrait orientation. Once I unlock the screen, onCreate() is called again, this time correctly in line with expected landscape mode dimensions.
I'm not sure how to handle this situation. I see the following options:
for each onCreate() call perform full layout calculation and resource scaling again. This is the logically correct solution, but I don't want to the same work twice, just to throw away the first result.
if onCreate() is called for portrait mode, just do nothing, and set black background (I can see there's a silly rotate animation when I unlock the screen, so this would become pretty much a fade-in animation)
Actually I'd prefer second option, but I'm slightly afraid of any side-effects. Anyone faced this problem?
Update (2012-07-08):
I've probably assigned a slightly misleading title to this question (sorry!), as the problem is not in retrieving the dimensions itself, nor calculating the layout. It's more about the activity being first created in portrait mode, and then recreated in landscape mode again, despite being declared as landscape-only. I initially expected (reasonably, huh?) the activity to be created in landscape orientation only.
I eventually decided to fill the activity with black color when it's created in portrait mode, no side effects observed. On Android 4.0 I can see actual rotation animation when I unlock the screen - a bit strange, but well, I guess it is supposed to inform the user that she should rotate the phone. Given that in portrait mode I just fill the screen with black color, this animation looks sort of like a fade-in and rotation combined - perfectly acceptable.
Use that
DisplayMetrics dm=new DisplayMetrics();
this.getWindowManager().getDefaultDisplay().getMetrics(dm);
Using this(Look code at down) only gives you screen size and if your views has static size they will be seen in different size on every different screen.
Display screen=getWindowManager().getDefaultDisplay().getSize();
How to use:
every screen has diffrent density. So use:
float density=dm.density;
with this density, you can set your views size like that:
(YOUR_ITEM_SIZE)*density;
also look here for additional information:
http://developer.android.com/reference/android/util/DisplayMetrics.html
if the emulator is locked , can't you assume that the user can't run anything anyway , so the app doesn't need to handle this end case ?
anyway , as bmavus wrote , use getMetrics for getting the screen size . also , if you need to change the screen orientation of the app , you can do so either in the manifest or in code.
for games , i would advice using opengl solutions , and if you don't have much time digging for it , you can use third party engines that can help you , such as andengine and libgdx.
I have a video that plays in portrait mode. At the end of the video, I need to display some views over it. This works fine so far.
I am however, having a problem where views that are over the last frame of a video don't redraw properly when coming back to the activity after turning the screen off, then on again, then unlocking the screen.
What i'm observing is that when the screen comes back on and I unlock. My video and images are first rendered outside of fullscreen mode (with the status bar still showing) then the screen will go into fullscreen mode shifting all of the views up and causing artifacting.
It seems like the views are being shifted out of their view bounds by the transition to fullscreen after they are rendered.
I'm really stumped as to how to prevent this from happening.
Here is the sandbox project on github to avoid making this a post full of code.
The basic setup for the project is this:
Fragment activity has a video view and a button view on it's layout.
It then adds a fragment into a contentView container. The contentView fades in 1 second prior to the end of video playback.
Everything works smoothly and the problem is with returning back to the app after powering the screen on and off.
Also, sometimes the video will just drop out entirely, leaving the views sitting atop a black background.
Thanks in advance for any help you can provide.
Here's the artifacting that happens when you turn the screen off, back on, and unlock.
Note that I had to take a picture of it. On DDMS the screenshot tool sees the images properly.
rather than prevent the screen from turning off, you can opt in to receive an event when the user unlocks the keyguard after waking the phone.
At this point, it might be a good idea to call View.invalidate on both of your views, this should cause a redraw. The draw chain is very flaky while the lock screen is up, because your app is technically visible, just under the lock screen.
registerReceiver(new BroadcastReceiver() {
#Override
public void onReceive(Context ctx, Intent intent) {
if(intent.getAction().equals(Intent.ACTION_USER_PRESENT))
}
}, new IntentFilter(Intent.ACTION_USER_PRESENT));
It looks like the overlay layout was shifted by controller bar.
Don't you think it was affected by controller (play/pause/ff/rew + progress) area?
there may be a way to prevent the screen going off in 1st place as this would be good resolving your re draw issues, hope this helps.
I am designing a application that uses the camera. I want it locked it landscape mode and just have the pictures(for example, a handle to change between camera and video) rotate. I don't want to launch onCreate() again. This is so the camera/video logo does not appear sideways on the screen.
I have put this in the manifest:
android:screenOrientation="landscape"
This keeps the screen from turning. However, I can't seem to figure out how I get the event that tells me when turn the images. I have seen camera apps do this.
Thanks!
If you've locked your activity using manifest, the only workable solution to track orientation I saw was using OrientationEventListener.
You'll need to convert degrees to correct orientation yourself. But that is relatively easy task.
I've managed to write a limited video player able to view a .3gp file from internet. The video will be shown centered full screen, maintaining the video aspect ratio. Also, rotations don't interrupt the video, which keeps playing without problems.
Everything seems fine, but... on my HTC Legend when you rotate back to portrait, the video is corrupted, and instead of showing full screen it is displayed at its native pixel size. But rotating again to landscape works and is shown perfectly. Any ideas why? Unfortunately I don't have more hardware to test this on and I've run out of ideas to test.
You can get the full example source code from https://github.com/gradha/Android-video-stream-rotation. Here are screen captures of me opening the application, rotating to landscape, touching the screen to display the video controls, then rotating back to portrait to see the corruption.
In the source code at https://github.com/gradha/Android-video-stream-rotation. you added the comment:
Since we specified in the
AndroidManifest.xml that we want to handle our own orientation
changes, we resize the screen in function of being portrait or
landscape.
From the source code AndroidManifest.xml
android:configChanges="orientation|screenSize"
So, if you add this attribute to the activity element in the manifest, I would interpret that as the activity will handle all the orientation changes? not you?
From Android Developers
To declare that your activity handles a configuration change, edit the
appropriate activity element in your manifest file to include the
android:configChanges attribute... more
So you should not need to:
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
}
I created a test project to check if this was the case:
Rotating Video Stream Example: https://github.com/TouchBoarder/RotatingVideoStream
My conclusion:
I did not need to overide the "onConfigurationChanged" in the activity to display the video correct in both portrait and landscape, and the video keeps playing on rotation changes.
Feel free to improve and use the code:)
Turns out my whole test case was wrong. Right up until the commit where I blame the easy videoview example on being wrong everything was according to the book. However I forgot the android:configChanges="orientation" line, and adding this line on top of the previously mentioned commit makes everything work without video corruption.
I'll be marking hsigmond's answer as valid for providing a test example I could compare to and find out the true problem. My whole working around this with custom orientation handlers and a subclass of the VideoView was wrong and incorrectly based on the question Android VideoView orientation change with buffered video. Not that that is wrong, I simply applied it incorrectly (plus other answers there also mentioned the missing android:configChanges).