I have three camera-based apps (that take still pictures) in the app-store and have got feedback that the UIImagePickerController interface is very slow - and I can't deny that. So, to improve the performance of the app, I started to experiment with the AVCam Demo source code from the WWDC 2010.
Since the AVFoundation framework does not interact with the UI Kit, I have been successful at wrapping a view around the demo. I am able to transition between the view controllers successfully. The only thing that I've modified is replaced the Record button with the Exit button (to exit to the wrapping view controller)
The modified app works fine during the first session (wrapper -> demo) If I exit the demo to the wrapper, and come back to the demo second time , the video frame in the preview layer freezes a second or two after. The app itself does not freeze - just the video is frozen. At this point, all UI buttons are active. But, when I tap "Still" button to capture the image, I get the following error in an alert:
The operation cannot be completed (AVFoundationErrorDomain error - 11800.)
This cannot be duplicated in the original demo code - because you can't close and reopen the session. So, I am wondering if it has anything to do with the way I "exit" from the session in my test. Here's the "exit" action that I added in the demo code:
- (IBAction)exit:(id)sender
{
[[self captureManager] stopRecording];
[self dismissModalViewControllerAnimated:YES];
}
Is this sufficient - or did I miss something?
Regards, Sam.
There's a little problem of cleaning up a capture session in an orderly fashion, as there's some asynchroneous calls with no alerts of when they're done.
Try stopping and releasing as suggested in this question:
How to properly release an AVCaptureSession
(take the solution with most up votes)
If that doesn't help you may need to post some more code here. Are you sure that's all you changed?
Good luck!
Oded.
Related
DukeScript is quite clever in the way it handle changes to the Model so that code is hot-swapped at runtime, see for example here.
One thing it doesn't seem to handle at Runtime though is changes to the HTML layout. Given it runs in a WebView, a kind of a browse, it would nice just to be able to reload the page without having to stop and restart the app.
So, I've tried adding a "reload" button, but I can't find an easy way to do that after the initialization:
BrowserBuilder
.newBrowser()
.loadPage("pages/index.html")
.loadClass(Main.class).
invoke("onPageLoad", args).
showAndWait();
showAndWait() does what it's supposed to do, it doesn't return until the browser is closed. There doesn't seem any way to act on the underlying instance of a WebView and its thread.
Ha ha, simple but effective solution:
Reload
Note: Toni Epple says NetBeans would just detect the change, no reload needed.
I have a main application calling several ViewStack states, each with popup windows. If I don't open any popup windows, I can move between states fine. If I open a popup window then try to change the state using currentState=... I get the error:
TypeError: Error #1009: Cannot access a property or method of a null object reference.
at spark.components::Scroller/focusInHandler()[E:\dev\4.y\frameworks\projects\spark\src\spark\components\Scroller.as:2139]
at flash.display::Stage/set focus()
at mx.core::UIComponent/setFocus() [E:\dev\4.y\frameworks\projects\framework\src\mx\core\UIComponent.as:9905]
...
I see others having the same problem, for example here:
http://forums.adobe.com/thread/1031531
http://forums.adobe.com/message/2767130
http://forums.adobe.com/message/3448443
http://forums.adobe.com/thread/655749?tstart=-1
http://forums.adobe.com/thread/801149
http://flex4examples.wordpress.com/2011/05/05/skinnabletextbase-focusmanager-runtime-error-popup/
http://bugs.adobe.com/jira/browse/SDK-32036?page=com.atlassian.jira.plugin.system.issuetabpanels%3Aall-tabpanel
But I haven't figured out how to implement the recommended solution. It sounds like I should just include:
import mx.managers.PopUpManager; PopUpManager;
inside my main application and it should work, but it doesn't work for me.
My application has each view state in a different file, each defined using <views:View>. Also, all of the popups are separate files defined as <s:TitleWindow>. Each file includes this line:
import mx.managers.PopUpManager;
I wonder if this means each file is using a different popup manager(?), when it's a singleton and only one should be used for the whole app (how to set that up?).
The code I use to call a popup is:
var _popupName:MyTitleWindowFileName = MyTitleWindowFileName(
PopUpManager.createPopUp(this, MyTitleWindowFileName, true));
_popupName.addEventListener(MyAppController.CLOSE_POPUP,onClosePopUp);
PopUpManager.centerPopUp(_popupName); // call popup
Note that when the main application (the one defined as <s:Application>) runs, the ViewStack states have not been loaded yet (since they get loaded when they are used the first time). Not sure if that has any cause/effect here.
I've tried to follow Adobe's example code in the "Passing data to and from a Spark pop-up window" section here:
http://help.adobe.com/en_US/flex/using/WS6c678f7b363d5da52e8f1ca1124a0430dcf-8000.html#WS6c678f7b363d5da52e8f1ca1124a0430dcf-7ffe
Any ideas much appreciated.
Based on your comments, it seems like the error occurs because the focus remains in the popup. I would expect the PopUpManager and FocusManager classes to handle this better.
One thing I can think of is that the FocusManager may be trying to handle this. But since the state changes, the item that originally had focus (in the view stack child, before the pop up was opened) may no longer be there when the view state changes. Just a hunch, w/out seeing your code.
Here's some things you can do to either work around the problem (or better) further debug it to understand what is happening:
Use FocusManager.setFocus() to move the focus back to an object in the view stack child before closing the pop up
Use FocusManager.getFocus() to debug and see where it thinks the focus is at various stages (before opening popup, before/after changing state, and before/after closing pop up).
It appears this is the situation I'm experiencing:
Adobe Air: scroller throws error when changes focus between different applications
It's an Adobe bug. Solution from Adobe is:
This bug is easily fixed by changing Scroller to do a null pointer check on focusManager before using it.
which is what the first link above attempts to do.
Another link: http://forums.adobe.com/message/3812805
I have an Ajax enabled website, with some calls to the Script Manager to set history points like so:
if (uxScriptManager.IsInAsyncPostBack)
{
uxScriptManager.AddHistoryPoint("x", taxid.ToString());
}
This works just fine 90% of the time.
However, about 10% of the time, the history points stop being set. This seems to happen when I've clicked around a bit and then start using the back button to go back pretty far (usually 6 or 7 steps in the history).
Has anyone else noticed/seen this behavior? The code I've got that picks up the state information from the history points to rebuild the page seems to work fine.It's just sometimes the script manager seems to forget to set the history point.
EDIT
I've noticed some strange behavior with the script manager - after the third or the fourth click back, is seems to break and the Ajax calls no longer work. The user needs to reload the page in order for the history to start working again. Anyone seen this type of behavior? (I'd think if I wasn't doing it right, it wouldn't work at all...)
I'm working on an app that, from the Main.mxml, opens one or many Window.mxml instances. When it's done I want all windows to be chromeless so the custom controls need to work.
In Main I've added applicationComplete="init();" so the init function gets ran, which contains clickhandlers, which makes the buttons work.
However, this way of running an init function doesn't seem to be valid for an mx:Window.
I can cheat by not using a clickhandler for the minimize and close buttons with a click="this.minimize();", but I don't know of a way like this to make the move work because it's a MOUSE_DOWN event.
Question 1:
Is there a way to have such an init function in an mx:Window?
Question 2:
What's a good way to make the buttons on the Window instances all work?
ps. If you think question 2 needs a separate post please let me know, they're so closely related and seemingly simple I couldn't decide.
Example code:
Main.mxml - http://pastebin.com/0HHVpkb8
Window.mxml - http://pastebin.com/g5TWuLYk
Window doesn't have an applicationComplete event, but it does have windowComplete event. Perhaps that would work for you. There is a list if Window events here.
I'm working on a Flex application that processes and displays small amounts of HTML, sometimes including images. I'm getting the HTML out of third-party RSS feeds. Sometimes, I see this in a pop-up window:
Error #2044: Unhandled IOErrorEvent:. text=Error #2035: URL Not Found.
The RSS URL is just fine, but there's apparently something in the downloaded HTML that's causing a problem. Since the application is meant to run as part of a non-interactive digital sign, anything that requires a click to continue is completely unacceptable. I don't care how useless or malformed a URL is; the app needs to ignore the problem without pestering the user.
Unfortunately, I'm having no luck trapping this event. I'm sprinkling calls like this liberally through the code:
[object].addEventListener(IOErrorEvent.IO_ERROR, handleIOError);
... where [object] is everything from the mx:Text object rendering the HTML to its mx:Canvas parent to the mx:Application top-level app, and handleIOError is a simple function that looks like this:
private function handleIOError(event:IOErrorEvent):void {
trace ("IO error occurred: " + event);
}
But so far, nothing; that bloody error keeps popping up in the Flash player. Does anybody have any insight as to where I'm going wrong?
Make sure you are putting the event on the right object. I haven't done a whole lot of remote loading in Flex, but in Flash, a hilarious and annoying quirk is that when you use the Loader class to load images, the object you need to put event handlers on is NOT the Loader itself, but a property of the loader called contentLoaderInfo.
Read the docs carefully on the objects you are using, a similar pitfall might be at play.
IOErrorEvent is not bubbled so you cant catch or control it if someone else is implementing it.
Please find out which third party component you are using and try to get source if its open source or read some documentation or ask support guys on how to turn off this alert.
For example, if I made RSS component for flex and on error if I displayed the alert, if you use my component, whatever you can do you cant turn off my error alert unless i have provided you a boolean switch to turn it off. So this is really a problem with who has written the code for this alert box. Whatever you do you will not be able to turn this thing off. Except reverse engineer, change the code and recompile it, but it should be legal.