I'd like to implement the method:"mapView:didUpdateUserLocation:"... Wierdly, when i test the app (even on a device), it seems the method doesn't get called.
I have set the map view delegate, done:
[myMap setUserTrackingMode:MKUserTrackingModeFollow];
[myMap.delegate mapViewWillStartLocatingUser:myMap];
but it hasn't worked.
You're not supposed to call mapViewWillStartLocatingUser yourself, it gets called if you give your mapView a delegate and then tell the map view to start showing the user's location.
Related
I've been battling with this over the last day, can't seem to get it to work correctly. I would share code but I feel it might confuse matters.
I've created a few ComponentDialogs that are needed to be included in other ComponentDialogs including the main bot.js.
ComponentDialogA is being imported into the main bot.js which gets called fine when I do a replaceDialog or beginDialog. But when I try can call ComponentDialogB from ComponentDialogA it just returns to the last point of ComponentDialogA and fails to hit ComponentDialogB.
So my sub questions are as follows:
Do I need a custom state accessor for each ComponentDialog in order
to do what I want to achieve or is that just for storing specific
data related to that dialog as opposed to the actual dialog position
Related to the first do I need a new dialogSet per ComponentDialog to
handle child ComponentDialogs, to use this.dialogs.add instead of
this.addDialog?
Am I just being dimwitted and messed up my code
somewhere?
I'll try and simplify my code and share later.
Many thanks,
First, there is currently a limitation in v4.2.x version of the libraries that prevent ComponentDialogs from accessing dialogs outside of itself in any way. This means that the dialogs inside of a ComponentDialog can only ever begin dialogs that are siblings to them within that ComponentDialog and never access the outside world.
In 4.3.x timeframe it will be possible for a ComponentDialog to begin a dialog "up" its ancestry chain as well. This means that, for your scenario, if both ComponentDialogA and ComponentDialogB were registered in the same parent DialogSet, ComponentDialogA would be able to call beginDialog('ComponentDialogB' ...) and it would find it.
To be clear though, you will still not be able to address individual dialogs within ComponentDialogs from the outside. Meaning, if your ComponentDialogB had a SubDialogX inside of it, something outside, such as ComponentDialogA, cannot start that "inner" dialog explicitly. Make sense?
I have implemented a TabBarController much like the Conference tutorial for iOS. Everything is working well now except it appears that the Init methods on Viewmodels for the tabs never get called as it normally would.
Is there something I forgot to do to ensure that Init is called? If I must, I could move this code to the constructor of the ViewModel, but I'd like to avoid this if possible.
EDIT
I guess what I'm really asking here is if I manually instantiate a viewmodel and "create" a view from it via the extension/helper methods, will init get called at some point in the process? If so, at what point can I expect init to get called on the viewmodel?
The Construction-Initialize-ReloadState-Start (C-I-R-S) sequence is called on an MvxViewModel if it is created using the default ViewModel locator - which is what happens when you call ShowViewModel.
If the ViewModels for the sub-tabs are created by calling new on a ViewModel directly - like in the Conference HomeViewModel.cs#L11 - then obviously this same sequence doesn't happen.
Really the difference here is between:
the tab ViewModels which are just INotifyPropertyChanged objects
the page-level MvxViewModels which are also INotifyPropertyChanged objects, but which you further expect to be initialized within navigations.
If you wanted to unify the two concepts then you probably could... but actually I suspect it might be simpler and cleaner to perhaps give the two class types different names, to just put the init code in the constuctor for the tab view models, or perhaps to just call Init on them yourself in the Home constructor.
I have made a HomeViewModel which contains some other ViewModels to be presented in a TabParPresenter. This works fine and the ViewModels associated Views are presented correctly in their corresponding tabs. However on of the ViewModels have a check in the ctor that tells it in when some conditions apply it needs to navigate to SettingsViewModel , which is not a part of the ViewModels contained in HomeViewModel.
The navigation event gets caught by the TabBarPresenterHost, which is simply the Presenter of the application and if a TabBarPresenter is present and not null it is passed to the TabBarPresenter.ShowView() method. All this happens before the TabBarPresenter is done loading and SelectedViewController is set in ViewDidLoad. Hence the TabBarPresenter relies on using the SelectedViewController to push new Views I obviously get a Null Reference Exception.
In short what I want is:
if (conditionForShowingHome == true)
GoToHome();
else
GoToSettings();
Then when inside SettingsViewModel I have set the stuff I need when going back you return to HomeViewModel.
What breaks this is that the ViewModels are loaded before the View is done loading and the navigation event is executed before the View is done loading. Any ideas how to go around this?
I'm afraid that putting this code inside a ViewModel constructor is likely to lead to problems.
The ViewModel constructors are called during navigations - and not all platforms will support starting new navigations while existing ones are still in progress.
To workaround this, I personally opt to put this type of behaviour in the code before the navigation.
In the case of a normal navigation, this can go inside an MvxCommand execution handler.
In the case of application startup, I do this in a custom app start - see some notes in https://speakerdeck.com/cirrious/appstart-in-mvvmcross
I've currently got two view controllers A and B, A uses a segue to push B and this works back and forth nicely, however based on some button presses in view controller B i want to change the text within a UITextView in controller A.
I've had a look at previous posts but i'm a novice at present and was confused by the way in which i should go about doing this.
I'd love to be able to get my head around how interactions are best done between various parts of the app. Also i was wondering if there is a way i can tap into a segue returning to trigger some other code.
Thanks
Edit:
OK perhaps i was a little bit limited with my information, from what i can gather reading other posts they are manually creating a variable for the viewcontroller (A) in viewcontroller (B) then accessing it in the second view controller (B) and setting a variable (property and synthesize) to edit that way, however i have the viewcontrollers embedded in a navigation controller and using a push setup in the storyboard (GUI system). I'm not sure if i have to create a variable to do this or if because they exist in the storyboard there is another way, if someone could just point me in the direction of a post that helps to explain this (i am looking at the moment too) i'd be very grateful.
OK well here's how i got it to work but i imagine there are:
A: Better ways to do it.
B: Changes depending on your setup.
I had my two view controllers embedded in a navigation controller, and used a segue push to access the second view controller each had a different class (all setup in the storyboard thing).
To get it working for me i did the following:
I have a singleton (a class that stores all my data but is global to the app so the variables can be accessed from anywhere in the app) this allows me to have variables that i can access from any view controller. A great tutorial on this can be found here
I then created an NSString variable (passedNote) and updated the value of this variable from the ViewController B, when my button was pressed.
Next when viewController A is loaded (in the viewWillAppear: (BOOL)animated method) i append or replace the value of the textview (dependent on some logic) I have with the global variable (passedNote).
Hope this helps anyone who had the problem.
Using the Reflection API to auto generate a UI.
How can I dismiss the keyboard when the user selects a new field, or if they choose a field which generates a new view to pick from. In the later case, when the user returns to the first screen, the old keyboard is still there.
UIView.EndEditing(bool force);
The above will hide the keyboard for you without needing to know who the first responder is. I haven't done much with the reflection API but you should be able to call that on the view when an element is selected.
Apple Docs -- endEditing:
Clarification for those initially struggling with the MonoDialog portion of the question:
The EndEditing method is not available on DialogViewControllers objects directly (who inherit from UITableViewControllers). You should be calling EndEditing(bool) on the View of a DialogViewController and not trying to call EndEditing(bool) on the actual DialogViewController itself.
For clarification:
DialogViewController dc;
dc.View.EndEditing(true);
Note:
UIView objects include the EndEditing(bool) method, but UITableViewControllers do not inherit from UIView so the EndEditing method is not available on the controller itself. UITableViewControllers contain a view object, call EndEditing on that view object.
Check the ResignFirstResponder method. This one should help you I guess.