I have a simple maps app with multiple pins on a map view. My intention is to tap a pin, show a callout with an accessory view, push to a Detail View Controller where you can edit that pin/locations details. This all works fine, but once i pop the Detail View Controller the callout on the map view is still there, which i want, but it still has the old uneditied values. How can i refresh/update the callout view once the Detail View Controller is popped?
I am using Core Data with a simple database. I have tried using controllerdidchangecontent, Map View Controller Will Display methods etc but my main problem is identifying which object has been added/updated/deleted and which is the corresponding callout/selected pin.
Any help appreciated...
Not sure if you had find your answer but the way to do it is to extend MKAnnotation class and creating custom annotation and passing them while creating placemarks. Later you can get them from MKAnnotationView's annotation property.
See a good implementation here
http://www.slideshare.net/360conferences/getting-oriented-with-mapkit-everything-you-need-to-get-started-with-the-new-mapping-framework
The only way I could find to update the callout info was to mess directly with the subviews of the callout.
The callout view is the first subview of the annotation view.
In the following example, I update the subtitle.The title label is the 6th and the subtitle is the 7th subview of the callout:
if (myAnnotationView.subviews.count > 0)
((UILabel*)[((UIView*)[myAnnotationView.subviews objectAtIndex:0]).subviews objectAtIndex:7]).text = #"Some example";
Related
I am trying to use SplitView in order to show the information about employees. There is a list of departments in the Master part. The list of employers working in the chosen department needs to be shown in the Detail when clicking on the department.
I am using CoreData with two Entities: "Department" and "Employee" that are connected with “to-many” relation.
How should I do it?
Thanks
This is a simplified overview, since you asked a very broad question.
Create a UITableViewController subclass to be your Master view. It should have a property of type NSManagedObjectContext, and it should handle fetching and displaying the departments. (You could fetch them in loadView, or you could use an NSFetchedResultsController…)
Create another UITableViewController subclass to be your detail view. Give it a property of type NSManagedObjectContext, and also a property of type Department. Make it display the employees for that department. You'll want to make it reload its data whenever the department property changes.
Add a property to your master view controller, to refer to the detail view controller (so a property of type EmployeeViewController, or whatever you called it). Then in tableView:didSelectRowAtIndexPath: in your master view controller, set self.employeeViewController.department = <selected department>.
Create the split view controller. If this is the top level view of your application, you'll want to create it in your app delegate, otherwise create it in the view controller that pushes it to the stack. Here's how to do it (in pseudocode):
Create a new detail view controller
Set its managedObjectContext property
Create a new master view controller
Set its managedObjectContext property
Set the master view controller's employeeViewController property to your detail view controller
Create a new split view controller
Set the split view controller's viewControllers property to an array containing your master and detail view controllers
Get the split view controller on the screen somehow, either by pushing it onto the navigation stack or setting it as your root view controller in applicationDidFinishLaunching:.
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.
I'm trying to accomplish switching views without using a navigation controller, tab bar controller etc. I am currently accomplishing this using Cocos2d director class replaceScene method. My application will need to have around 40 view controllers, each with a few UIButtons that could take them to any other view controller.
For instance View controller 1 may have buttons that take you to view controller 2
View Controller 2 may have buttons that link to 3,4,5,12
view controller 4 may need to link to view controller 17, 5 and 3
Every tutorial and bit of documentation I've read only discusses using Navigation Controllers, Tab bars or pushing views modally. None of these solutions fits my particular requirements.
Cocos2d has the "replaceScene" method which does exactly what I need, but mixing the many UIKit controls that I need makes developing this entire project in Cocos2d a nightmare.
I'm looking for something where I can have the user tap a button which will load a specified view controller/view transition to that view, and unload the previous view controller from memory. Any ideas?
Have a root view controller which has references of your view controllers. Also make a weak reference to the root view controller in each view controller, as in a delegate pattern. If one of the view controllers wants to make a view transition, send a message to the root view controller. Let the root view controller hide the current view and unhide the next view, using an animation if you want.
Basically you are implementing a view container much simpler than UINavigationController and UITabBarController. You could probably achieve the same thing using the tab bar controller and hide the tab bar view, but I would implement a custom one.
my question is about view controllers, delegates and all that in general. I feel perfectly comfortable with UIView, UIViewController, Delegates and Sources, like UITableView does for instance. It all makes sense.
Now I have implemented my first real custom view. No XIBs involved. It is an autocomplete address picker very much like in the Mail application. It creates those blue buttons whenever a recipient is added and has all the keyboard support like the original.
It subclasses UIView. There is no controller, no delegate, no source. I wonder if I should have either one of those? Or all, to make it a clean implementation.
I just cannot put my finger on the sense a view controller would make in my case. My custom view acts much like a control and a UIButton doesn't have a controller either.
What would it control in my view's case?
Some of my thoughts:
For the source: currently the view has a property "PossibleAutocompleteRecipients" which contains the addresses it autocompletes. I guess this would be a candidate for a "source" implementation. But is that really worth it? I would rather pass the controller to the view and put the property into the controller.
The selected recipients can be retrieved using a "SelectedRecipients" property. But views should not store values, I learned. Where would that go? Into the controller?
What about all the properties like "AllowSelectionFromAddressBook"? Again, if I compare with UIButton, these properties are similar to the button's "Secure" property. So they are allowed to be in the view.
The delegate could have methods like "WillAddRecipient", "WillRemoveRecipient" and so on and the user could return TRUE/FALSE to prevent the action from happening. Correct?
Should I maybe inherit from UIControl in the first place and not from UIView?
And last but not least: my custom view rotates perfectly if the device is rotated. Why don't all views? Why do some need a controller which implements ShouldAutoRotateToDeviceOrientation()?
Does it make sense what I wrote above? In the end I will provide the source on my website because it took me some time to implement it and I would like to share it as I have not found a similar implementaion of the Mail-App-like autocomplete control in MonoTouch.
I just want to learn and understand as much as possible and include it in the source.
René
I can answer part of your question.
I just cannot put my finger on the
sense a view controller would make in
my case
The ViewController is responsible for handling the View's state transitions (load, appear, rotate, etc) These transitions are used mainly when you use a navigation component (UINavigationViewController, UITabBarController). These components needs to received a ViewController that will handles the view's transitions.
For exemple, when you push a ViewController on a UINavigationViewController, it will cause the ViewDidLoad, ViewWillAppear, ViewDidAppear. It will also cause the ViewWillDisappear, ViewDidDisappear of the current ViewController.
So, if your application has only one portrait view, you don't need a ViewController. You can add your custom view as a subview of the main window.