How do I prevent my GUI from redraw when it comes back from lock screen after receiving a UILocalNotification? In didReceiveLocalNotification I present a modal view, but the old state of my view controllers is shown for a moment before that. How do I prevent this?
Also the order of events I get when I come back on local notification from background is as following:
1. UIApplicationWillEnterForegroundNotification
2. UIApplicationDidBecomeActiveNotification
3. didReceiveLocalNotification
When I come from lock screen:
1. didReceiveLocalNotification
2. UIApplicationDidBecomeActiveNotification
Why is this difference and whether there is something else I'm missing?
Thanks
Here's how it was solved. May be it's not the way, but it worked for me. Since my application is voip/audio, it doesn't come to didFinishLaunchingWithOptions... I found out, that iOS uses a cached image from a previous state for animation when it resumes from background or from sleep mode. So the solution is basically to exchange this cached image with my default.png image. I do it in applicationWillResignActive delegate. There I add a modal view with a Default.png picture and dismiss it in applicationDidBecomeActive. This is really in short. Hopefully it will help somebody else with the same problem.
You can provide a custom image that is displayed when launching/resuming from a local notification. Simply set the alertLaunchImage property on your local notification to the name of the correct image.
From the Docs:
The string is a filename of an image file in the application bundle. This image is a launching image specified for a given notification; when the user taps the action button (for example, “View”) or moves the action slider, the image is used in place of the default launching image. If the value of this property is nil (the default), the system either uses the previous snapshot, uses the image identified by the UILaunchImageFile key in the application’s Info.plist file, or falls back to Default.png.
alertLaunchImage
Related
I have build an application using touchGFX and STM32 based on STM32F746 Disco kit.
My application have some screens with some value to display on screen. These value can setting and change by user. Every time when these value change I will save them to eeprom.
When I turn off power and turn on again, I have read these value before start display screen, but them can't to load to screen until I pressed some button on screen (pressed button I will fresh this screen).
So my question:
How can I initiate customer value for screen and display them when startup in touchGFX
Thanks.
This is simple, just load your data in presenter->activate().
I suggest you read the article on back-end-communication. It explains how to propagate values from your Model (e.g eeprom).
https://support.touchgfx.com/4.18/docs/development/ui-development/touchgfx-engine-features/backend-communication
From TouchGFX Designer you'll find several examples that do something similar from an F769-DISCO board (sample a button and propagate that value to the UI).
In the simple Dialog below:
// choice of layout has no impact:
Container cont=new Container(new TextModeLayout(3, 1));
//Container cont=new Container(new BoxLayout(BoxLayout.Y_AXIS));
TextComponent firstName=new TextComponent().label("First Name").text(person.firstname);
TextComponent lastName=new TextComponent().label("Last Name").text(person.lastname);
TextComponent cost=new TextComponent().label("Cost per Session").text(person.getCostString());
cost.getField().setConstraint(TextArea.DECIMAL);
// NOTE HERE
// doesn't work: // works:
cont.add(firstName); // cont.add(firstName.getField());
cont.add(lastName); // cont.add(lastName.getField());
cont.add(cost); // cont.add(cost.getField());
Dialog.show("Edit Client", cont, new Command(CANCEL), new Command(OK));
Nothing appears in the Dialog unless I add the TextField instead of the TextComponent to my container at the NOTE HERE comment. This means I lose the nice appearance of the labelled input fields (yes I know I could label them myself, but they wouldn't look as good on different devices). My choice of layout manager at the top does not affect this issue (I've tried several). I can't find evidence online to conclude there's an incompatibility here, adding TextComponents and other InputComponents works fine on a Form, just not in a Dialog.
I'm having the same problem in another Dialog that uses PickerComponents. The PickerComponent doesn't appear unless I add the Picker itself, and then the Picker spawned from a Dialog looks all wrong. I'm hoping the simpler code question above will answer this quandary as well.
It's worth noting I've made no theme changes and this problem is noted in both the Android and Apple skins as well as on an actual Android phone. Thanks in advance for any help!
You shouldn't do input in a Dialog as it creates a very problematic user experience. If you would like things to look like they are in a dialog you can use styles and layouts to make a Form feel like a Dialog but you shouldn't use a Dialog.
The reason this fails is a bit complicated but here are the high level problems with using a dialog:
Dialogs don't grow implicitly - This is a huge problem for text input as the component needs space to resize with input and even more so for the animated TextComponent which needs to shift things around. The size of a Dialog is determined when it's shown and that's a big problem
This becomes a bigger problem on Android where the screen resizes during input and distorts the dialog completely. It's one of those things you'll only see on the device because it's really hard to simulate the virtual keyboard.
Scrollability is hard in a Dialog and text components need a scrollable parent so you can scroll between the various edit components
Picker component uses a form of Dialog to show input and this can collide with your dialog
Dialogs are hard to get right for suspend/resume behavior. Suspend/resume happens when the app is minimized or sent to the background. E.g. say you have an incoming call while typing in the dialog. When you go back to the app we want to show the last form. If we show the dialog it will block and we won't know which parent form to show anyway. So when an app is suspended dialogs are just disposed in the default code generated in the main class. It makes more sense.
I'm working in a legacy application using MFC.
We have a mechanism to enable/disable controls depending on some business logic.
This mechanism is implemented in the CView-derived class. The way it works is all the views in the application derived from a common CView-derived class (CBaseView) and on the PreTranslateMessage all controls of the view are enabled/disabled.
This worked fine so far because all controls send at least WM_PAINT message when they need to be painted. So the system worked without the user having to move the mouse or anything. I recently added some drawing features and I had to use WS_EX_COMPOSITE to get ride of some flickering. With this flag activated my CView-derived class is not getting any called to PreTranslateMessage when creating the view....so the controls are not disabled until the user moves the mouse over the control.
I understand there is no way to send WM_PAINT using WS_EX_COMPOSITE but is there other message I can use to get the same behaviour???
Edited:
I am currently using the OnIdle approach but it has a big drawback, the windows doesn't become idle until after drawing all the controls...so when you enter the screen al controls are enabled and inmediately they are disabled...this makes a quite ugly effect!
More solutions???
Thanks in advance...
The logical place to enable/disable controls would be CView::OnUpdate, it is called by the framework after the view's document has been modified and from OnInitialUpdate(); you can also call this function if there is some change that would trigger re-evaluation of your business logic.
EDIT
After reading the question a bit more closely, what you could also do is to post a private message at the end of OnInitialUpdate and "catch" it in your PreTranslateMessage:
PostMessage(WM_APP, 0, 0);
Calling InvalidateRect followed by UpdateWindow against the window in question will mark the entire client area as dirty and force an immediate repaint. Remember that WM_PAINT is not really a message, in the queue in the usual sense, it is pushed out after all other messages have been processed for that window, which would include any invalidations of the area being drawn. No message is generated at all if there are no invalid segments of the active window display.
How do I prevent my GUI from redraw when it comes back from lock screen after receiving a UILocalNotification? In didReceiveLocalNotification I present a modal view, but the old state of my view controllers is shown for a moment before that. How do I prevent this?
Also the order of events I get when I come back on local notification from background is as following:
1. UIApplicationWillEnterForegroundNotification
2. UIApplicationDidBecomeActiveNotification
3. didReceiveLocalNotification
When I come from lock screen:
1. didReceiveLocalNotification
2. UIApplicationDidBecomeActiveNotification
Why is this difference and whether there is something else I'm missing?
Thanks
Here's how it was solved. May be it's not the way, but it worked for me. Since my application is voip/audio, it doesn't come to didFinishLaunchingWithOptions... I found out, that iOS uses a cached image from a previous state for animation when it resumes from background or from sleep mode. So the solution is basically to exchange this cached image with my default.png image. I do it in applicationWillResignActive delegate. There I add a modal view with a Default.png picture and dismiss it in applicationDidBecomeActive. This is really in short. Hopefully it will help somebody else with the same problem.
You can provide a custom image that is displayed when launching/resuming from a local notification. Simply set the alertLaunchImage property on your local notification to the name of the correct image.
From the Docs:
The string is a filename of an image file in the application bundle. This image is a launching image specified for a given notification; when the user taps the action button (for example, “View”) or moves the action slider, the image is used in place of the default launching image. If the value of this property is nil (the default), the system either uses the previous snapshot, uses the image identified by the UILaunchImageFile key in the application’s Info.plist file, or falls back to Default.png.
alertLaunchImage
I have a core data document based cocoa app that is working well except for one slightly odd problem.
For some reason, if I make a change to any of my fields the menu/window don't seem to recognize it - ie. the red close button doesn't get the black 'dirty' indicator and the File/Save menu item isn't enabled. However, if I attempt to close the application (via command-Q), I do get the popup asking me if I want to save my changes.
It seems that the document's dirty flag is being set, but the window/menu items aren't reacting to it. I am curious as to where I might look to see why this might be the case. I suspect that it may have something to do with my window not knowing about my ManagedObjectContext...
The only slightly atypical behaviour is that my document's makeWindowControllers method has been overridden and I am adding my window controllers using a call to my document's [self addWindowController:xxx] method. My window controllers subclass from NSWindowController so I had to add my own instance variable to each window controller to hold the ManagedObjectContext, but I suspect that this isn't getting passed to the window/menu. Not sure what the normal pattern is here...
Anyway, any thoughts would be much appreciated. Thanks
From the description it sounds like your UI elements are not actually bound to the document itself. If so, then the UI elements are not observing the document and are not reacting to changes in the document. Check the bindings.
Thanks in part to TechZen, and also re-reading my own question (in particular, where I said "I suspect that it may have something to do with my window not knowing about my ManagedObjectContext") I started to look at the bindings for my WindowController subclass.
As it turned out, I hadn't bound the window outlet for the File's Owner to my actual NSWindow. As soon as I did that, the black dirty dot and the window's menus started behaving correctly.