A quickie...what (if any) method is called when the user dismisses a UIPopover by tapping outside of it? If I want something to happen at this point, where is my hook?
In UIPopoverControllerDelegate we have delegate method called popoverControllerDidDismissPopover: Read : Doc for greater understanding about how to use it.
Related
I need to show a sheet dialog soon after the main window has been shown after first run. If I do it in the init or awake from nib , it does not seem to work right (sheet show as window detached from main window if I do it in the init method). I guess I have to show sheet once the parent window has shown. I have an appcontroller class which has a window pointer. So I guess I need to register as a delegate or something with window ? and implement some method to receive that call ?
Thanks,
There is no reliable event, notification, or delegate method call. It is expected that your code is responsible for showing the window, so it should already know when the window is shown.
Are you relying on the Visible at Launch property set in Interface Builder? If so, what you using to load the NIB? Hopefully, a window controller. In that case, you should be calling the -window method to load the NIB and obtain the window. The resulting window reference is what you would pass to the method that begins the sheet.
If not relying on Visible at Launch, what code are you using to show the window? For example, invoking -showWindow: on the window controller? So, put the code to show the sheet right after that.
applicationDidFinishLaunching: is your entry point. It is sent to your app delegate after the app is all set up, but before the user has had a chance to interact with it.
My Setup
I have a ViewController, where users type some sort of text in there. Call it InputViewController.
I have a UIView (in a separate class), where I draw a navigation bar that has a gradient (I override drawRect for Core Graphics, hence I need to to have in a separate class) which has a button. The button takes you to a MapViewController, which allows you to add a location tag to your input. Once a location tag is added, I would like to change the button's image.
My Problem
Once the button is tapped, I need to send the user's input to the MapViewController, where a delegate is also implemented and will pass back some information back to the InputViewController. The issue here is that the button resides in the separate UIView. One way to do this is pass the UIView the information once they are set, which in turn would be passed to the MapViewController once the button is tapped. The problem here would be the delegate as the delegate needs to return to the InputViewController and not the `UIView.
I was wondering if its possible to move the UIView into the InputViewController, including the drawRect method for that view. If so, how can I do that? If not, what are other ways/suggestions I can do to have the above set up?
I guess you need to use NSNotifications for sending messages to your classes. See this.
I have a problem, I want to show right delete confirmation button of my UITableView's cell. Swipe to delete works just fine but I also want this to happen without swiping.
I would like to change cell's state from default to showing delete confirmation. There is bool property showingDeleteConfirmation but it's read only.
[self setEditing:YES animated:YES];
From custom cell's class doesn't do anything.
How to change cell's state to showing delete confirmation without swipe?
i.e. after swipe gesture on a cell is recognized what is being called? I would like to call it manually.
That is a delegate method meaning you should not call it yourself as that is a part of the process handles by the tableView class.
Instead you'll want to override the call class, prepare the method to show your button (or whatever you want to show) and animate other views trimming their frames. Doing that you'll understand the difference between the delegate and instance messages as you'll probably need to notify the tableView or it's delegate that your method is complete, the button is shown and other views are also animated.
Must I always resignFirstResponder for a UITextView? Or, will this happen automatically when its view controller disappears?
I'm asking because I'm having an issue similar to iPhone Objective-C: Keyboard won't hide with resignFirstResponder, sometimes, where the keyboard stays up even when the nav controller pushes and pops other view controllers. The keyboard works, and when I hit done, it unfocuses the UITextView (i.e., the cursor disappears), but the keyboard stays up.
I never found out why this is happening, but maybe it's due to not doing resignFirstResponder before pushing another view controller, but I thought it was optional?
At a total guess, the UITextView has a reference to the view controller (as its delegate) but does not retain it. When you go to the next screen, the controller is dealloced and then the UITextView (which has perhaps been retained by something else) tries to call back to the dealloced controller and crashes. When you call resignFirstResponder, you reverse the order this happens, and therefore no crash.
The way round this to add a textView.delegate = nil call in your view controller's dealloc method - obviously put it before you release the text view.
The contract between a UITextView and it's delegate says that the delegate will send -resignFirstResponder when the text view is done editing. This informs the framework that the view is done editing, fires the events relating to that (willEndEditing and didEndEditing), and allows other parts of the responder hierarchy to react accordingly. Failing to do so might work, but it's not following the contract (that's all a protocol is) it agreed to.
I don't think you have to because the Xcode Sample UICatalog UITextField doesn't call resignFirstResponder before the TextViewController is popped.
The reason the keyboard got stuck for me is that I was having the same view controller present two view controllers modally at the same time, one after the other. UIKit didn't like that.
Calling resignFirstResponder makes sure that the text property contains the actual text shown in the control.
Depending on the state this is not always necessary, but if your controls have resigned first responder, you know that you're working with valid data.
Consider this view setup :
I have a view controller which switches between a set of sub views. Each sub view is a UIView subclass with custom code. To switch views I use a switch statement which allocs the new view as the currentview. This works very well.
I'm now in a position where I have a view (MainMenu) with a sub view (PopUp) that contains a UITableView. The PopUp view is shown and hidden via instance methods of the MainMenu.h class. Lets call the methods showPopUp and hidePopUp.
When a user selects an item from the UITableView they then have to manually close the containing (PopUp) view by clicking the close button, which is bound to the hidePopUp method.
What should happen when a user selects an item in the UITableView is that the hidePopUp method should be triggered automatically.
How do I trigger the hidePopUp instance method via the didSelectRowAtIndexPath of the UITAbleView? Is this a job for an app delegate, or perhaps NSNotificationCenter? I've tried such things as calling
[[[UIApplication sharedApplication] delegate] closePopUp];
from the didSelectRowAtIndexPath to no avail...
Thanks in advance, it's probably something simple I'm missing. Programming with a flu is difficult!
There are a few ways to accomplish this, such as notifications or working through a singleton like the app delegate (although the use of the singleton [anti]pattern is not without controversy). Personally, I'd use delegation.
Something like:
#protocol PopUpDelegate
#optional
- (void)Popup:(YourPopUpClass *)popUp didEndWithData:(NSData *)blah;
#end
You could then implement this protocol in your MainMenu, assign it as Popup's delegate, have the Popup call the delegate's method when the close button is pushed, and close the popup from there.
Here's a great post on how to implement delegates if you choose to go this route: How do I create delegates in Objective-C?