I have written code so that technically there should be two MPMoviePlayerControllers within the same view, both ready to play an audio file. What always happens is that one pops up and disappears, and the other comes up and stays, and is fully useable.
Any idea why one disappears? I'm not trying to play two at once, just want to give users the option to play from different sources.
There can only be one active MPMoviePlayerController, it won't mind if the user didn't play it yet. I do not know the technical reason, but I do know that this is the normal behavior when you do that.
My advice would be to use AVAudioPlayer to achieve what you want. The sad part if that you will have to implement the UI of the player.
Related
I'm looking to implement a UIPickerView where the user presses spin and the picker selects a random option. I'm curious if there are any ways to make the spinning effect last longer?
The only way I've really thought of, or seen, is increasing the number of items in the component simulating that the picker is really "spinning". Is this my only option?
Thanks.
You may test the actual performance with the huge number UIPickerView first, or actually build a slot machine component like this one:
iPadSlotMachine
With the stock iOS controller, no, I do not believe this is really possible.
Your idea might work, but will probably suffer from some graphical glitches as you add/remove elements during animation. Definitely worth trying though, to see if it is good enough for your needs.
Unfortunately, I think you'd have to write your own custom controller to really get the "slot machine" effect you're after properly. I would suggest google around and checking github, etc to see if anyone has written an open source one.
Im trying to find the best way to avoid having tiny UI lockups after certain events in my app. For example here are two cases where i have come across mini-lockups:
I have a button that when pressed loads a local mp3 file (around 20-30mb) using AVAudioPlayer, calls the prepareToPlay method and then plays the audio file. The issue is that the button has the showsTouchWhenHighlighted flag set to yes and after pressing it it stays highlighted until the audio file begins playing which could take 1-3 secs.
Another similar example is using a navbar button to sort and reload the table data. There is a very short but noticeable lockup where the button remains highlighted until the table has reloaded.
Can anyone suggest a good approach to minimizing/eliminating these mini lockups? I didnt really come across any code to achieve this in any of the books/tutorials i read that dealt with tableviews and avaudioplayer. Should i be launching these actions on different threads?
thx
For number 1, your best bet is to load the item on a background thread and inform the user that you're doing so (either via a loading HUD or some other indicator). The simplest way of doing this will be to use - (void)performSelectorInBackground:(SEL)aSelector withObject:(id)arg;. If you're running iOS 4.0 + you may want to look into executing block callbacks and see if they will work for you.
For number 2, perform the sorting on the background thread or change your sorting method (consider using a sorted data structure rather than resorting after inserts?). reloadData should occur only on the main thread.
I'm an iPhone noob myself, but it sounds like your code is stuck doing synchronous actions, which will guarantee that your UI gets locked up until the action is done executing.
Although I don't have an explicit answer, look for asynchronous options to perform these actions as they will not lockup your UI. These are usually achieved through using threads or deferred objects. From my experience so far w/ Objective-C, most actions your program neds to take can be achieved through async actions.
I have to figure out the best way to transition from one video to the next
BASIC IDEA: An example would be that there is a video of a person walking.....the user taps the video and a seamless transition occurs to a video of a person running (over simplified example)
My first thought was to create 2 movie players and use transitions between the 2 view elements. But movie-player doesn't support that.
stopping the current video, loading new content, and then starting it is a solution but not very elegant. We are making a interactive sales tool for our reps and we want this to look as professional as possible.
CURRENT THOUGHT: If there was some sample code for AVPlayer, it would seem I could use AVVideoComposition to switch between videos? But details on how that might happen don't seem to be currently available.
POSSIBLE CLUE: I figured this would be easy as I bought an app called Live Cams HD that shows 16 different video feeds at once.
Any ideas? Thanks in advance!
Steve, the short answer is that you are not going to be able to get the kind of results you want using AVPlayer. The h.264 video logic included in iOS is really great at playing video and video/audio together, but it really sucks at starting/stopping and switching from one clip to another. The reason is that there is a lot of buffering that needs to happen to load up and start playing a h.264 video in hardware. Basically, you need to roll your own code that sets UIImage/CGImageRef for your views in a way that makes it easy to switch from one clip to another by simply switching from one array of UIImage objects to another. Of course, that is easy to say yet not so easy to implement.
What I would suggest is that you evaluate existing code that already implements this logic instead of rolling your own. For example, have a look at this StreetFighter demo app. It shows how a very simple game like iPhone UI can be constructed using a series of clips that show a character doing a kick, a punch, or throwing a fireball. The results looks like this:
I also wrote up a blog post about seamless-video-looping-on-ios. You can of course roll your own code to do all this, but I would suggest reading more about my library at the linked website as it will save you a lot of time.
After the first video has played every frame except the last one, you quickly swap to a view with an image of the last frame (basically the last frame) and then you transition into a view with the an image of the first frame of the next video and start up that one.
Or you could create a animation with all your frames (programming your videos), that will make it customizable, but the quality will probably not be as good and the cpu usage can spike, so you will have to make a call on that one.
I am trying to play video without showing controls (volume and other buttons) but it also should be possible to make them visible by taping on the video.
The code is:
theMovie.scalingMode = MPMovieScalingModeAspectFill;
theMovie.movieControlMode = MPMovieControlModeDefault;
In this case it shows the controls by default and by taping on the video they get hidden.
If I change the mode to MPMovieControlModeHidden then I can not see the controls but also I can not bring them back.
Is there a way to start video without controls but not disabling them completely?
Good news Dmitriy!
I've found a solution that will do the job for you, I hope.
It is as follows:
Initialize your
MPMoviePlayerController object's
movieControlMode property with
MPMovieControlModeHidden value
Play the movie
After the movie playback has started set your MPMoviePlayerController object's movieControlMode property back to MPMovieControlModeDefault
Third step can be accomplished by observing MPMoviePlayerContentPreloadDidFinishNotification notification. Though this might cause unresponsive black screen (or of another color you've set as your MPMoviePlayerController object's backgroundColor) in case you will play a streaming video, which be actually preloaded by MPMoviePlayerController. I don't have any movie of compatible format on a remote server at my disposal right now so I can't test this scenario is real and therefore mess around to see if there's something that can be done to avoid this side effect (though I think I will do that if you publish or find such movie for testing somewhere in the Internet).
Tip: look at the bold piece of text if you don't want to know my long story about how boring I am actually starting to look into a problem by reading the documentation and looking into the sample code it offers.
You question has interested me so I started from looking at MPMoviePlayerController Class Reference on iPhone Dev Center. I didn't actually find anything related to the problem you've stumbled upon so I've decided to play around with this sample project MPMoviePlayerController reference - MoviePlayer. I juts wanted to reproduce your situation and maybe try dealing with it by simulating a single touch event or triggering the same method that responds to this event manually.
But it turned out that Apple's sample project in fact behaves absolutely like you want your's to. It starts video playback and the overlay controls are automagically animated out of the screen from the very beginning. I've looked through the code, it's rather simple and doesn't really 'deal' in any way with this problem you have. So maybe it's something you do (or do in somewhat not right order) that causes the problem. Check it out and get back to us with a cure because judging by usefulness metric there are people who have similar problems.
I have a quicktime file (.mov) generated by Keynote. When played in quicktime, it pauses itself at dozens of pre-defined points waiting for user input. It is basically a slide show with transitions pre-rendered to video.
I want to wrap this in an iPhone app, but see no methods on an MPMoviePlayerController to do anything other than play, which does not pause at the pause points.
Also, I want to be able to play backwards to a prior stop point if the user taps elsewhere on the phone.
Is there a better library for this than MPMoviePlayerController or (deprecated?) UIMoviePlayerController? Or am I overlooking methods that would allow this?
If you think about what you're trying to do, this is actually a fairly complex task. What you're really asking for is the ability to hook up an arbitrary movie playing UI tied to unique gestures, based on the specifics of your movie. I don't think either of the classes in question is going to get you there.
The easiest solution here might be content-based: generate one quicktime movie per "group" of Keynote slides, where each group ends at a pause point, and then it should be pretty easy to interpret gestures to either advance to the next movie (or load it automatically when you reach the end of the last one), or return to the start of the currently playing movie.