What are the "First Responder" and "Exit" boxes purpose in the storyboard editor? - ios

In the XCode IDE, at the bottom of the view controller in the MainStoryboard editor, are two boxes: First Responder, and Exit.
I know what a firstResponder is programatically within the code, but in the storyboard editor, I can't seem to do anything useful by it.
Am I able to use the first responder in this area to somehow set the first responder of the view? I'd like the first textfield to be active on load and I have tried right+click and dragging to no avail. I know I can set it programatically in the viewDidLoad method, but is there some way of doing it here?
And what is the green Exit for?

There are no good answer for this question, so I am posting my answer:
From here:
Note: You probably won’t be using the First Responder very much. This is a proxy object that refers to whatever object has first responder status at any given time. It was also present in your nibs and you probably never had a need to use it then either. As an example, you can hook up the Touch Up Inside event from a button to First Responder’s cut: selector. If at some point a text field has input focus then you can press that button to make the text field, which is now the first responder, cut its text to the pasteboard.
Edit:
1) First Responder is very useful if you are using text fields with keyboard notifications. I use it to make keyboard disappear, make an outlet to variable currentFirstResponder of your class, and in viewWillDisappear:
[self.currentFirstResponder resignFirstResponder];
2) You can read about unwind segues ("Exit" box) here

I've never used it and probably never will but you can assign an object to be the first in line to receive the events from the UI.
I suppose you could be creating a UIView subclass and add it in to a UIViewController but you actually want some other object to receive and process the events other than the UIViewController you are adding it to.
I found this link which kind of explains it a bit better.

First Responder: The First Responder icon stands for the object that the user is currently interacting with. When a user works with an iOS application, multiple objects could potentially respond to the various gestures or keystrokes that the user creates. The first responder is the object currently in control and interacting with the user. A text field that the user is typing into, for example, would be the first responder until the user moves to another field or control.
Exit: The Exit icon serves a very specific purpose that will come into play only in multiscene applications. When you are creating an app that moves the user between a series of screens, the Exit icon provides a visual means of jumping back to a previous screen. If you have built five scenes that link from one to another and you want to quickly return to the first scene from the fifth, you’ll link from the fifth scene to the first scene’s Exit icon.
More here

You don't see this very often, where a deleted answer is actually correct, and the comment (likely influencing its deletion) on it is totally wrong! I'll try and improve on it.
Usually the IBAction you want to hook up to a button is in the view controller containing the button. However if the IBAction is in a different controller, e.g. a parent controller then drag from the button to the First Responder object and you are able to select the IBAction in the parent controller!
As the hidden answer states, how this is implemented is the action is sent to nil, which has the effect of the responder chain (i.e. view hierarchy) being searched for the action, as follows:
[UIApplication.sharedApplication sendAction:#selector(nextObject:) to:nil from:self forEvent:nil];
An example is a custom UITableViewCell. Add a UIButton to the cell but you want the action to go up to a View Controller that has an embed segue to a UITableViewController. Drag the touch up instead action to the First Responder and select the action in the container view controller. In the action to find the indexPath simply loop the visibleCells and check if the sender is isDescendantOfView:
- (IBAction)cellButtonTapped:(id)sender{
for(UITableViewCell *cell in self.tableViewController.tableView.visibleCells){
if([sender isDescendantOfView:cell]){
NSIndexPath *indexPath = [self.tableViewController.tableView indexPathForCell:cell];
NSLog(#"tapped %#", indexPath);
}
}
}
Another example could be a reload button: say your first view controller shows an downloaded item with an IBAction to reload it to get the latest data, then your child controller shows some detail, but you also want them to be able to reload the main item from within the detail, just add a button in the detail and drag its action to First Responder and select the reload IBAction in the parent controller. This allows you to hook up buttons to parent actions with no additional code like delegate methods!
For this to work the action needs to be in the responder chain hierarchy or it won't be found, you can read how the chain is built up in the docs. Also note if called from code the view needs to have appeared, viewWillAppear is too soon.

Related

How to make a floating/3D Touch style tableview?

So i'm making an application for tracking livestock. I have made a table view for the animals to go in. I have a navigation controller at the top with a button in side of it.Here is what i have so far.
I would like to have a floating table view come up when the button is pressed similar to the 3D touch menu.
Like these.
My question is how would i go about doing this. Sorry if this is a commonly done thing im pretty new to swift and xcode
If you just wanna to implement,you could search the key words as 'pop over', 'kxmenu' or 'menu' on GitHub/CocoaControls. such like this: https://github.com/zpz1237/NirKxMenu https://github.com/liufengting/FTPopOverMenu
Also, you should make it yourself. When the button is pressed, first you should create a custom window and make it key window. Secondly, add a tableView or a view contains tableView to the custom window. then, use block or delegate to deal with data communication and respond user interaction. After that, design animation you need. At last, remove subviews from custom window and make the original window key window.

Objective C: show textfield and textview input in label on next view?

So i've seen many questions alike mine, but all don't have the working answer, or have vague answers (and none of them marked as correct).
I have two ViewControllers:
ViewController #1 has 4 textFields to which there are pickerViews attached in order to choose an option to fill in the textfield.
Also there is 1 textView in which the user can use the keyboard.
To sketch the scenario: Label states: 'Pick a color:' User clicks on the textfield (pickerView shows up full of names of colors) user selects 'red' and the picked choice shows up in the textfield below the label: 'pick a color'.
Then when all textfields and textview are filled in, the user clicks save. In which the save button redirects the user to the 2nd ViewController.
ViewController #2:
This is where i want the input (of the textFields and textView) to be shown in the labels(if this is the correct usage). Since this is where the user will see list of the chosen answers. However i cannot manage to get this working.
What do i need to do in order to achieve this?
Also i'm still learning. Please bear with me.
Thanks in advance.
In general this site is not well-suited to "Tell me how to do XYZ" type questions. It's intended for getting help with code you have already written. You're new, though, so I'll take pity on you.
You should post the code that you have, showing how you get from view controller 1 to view controller 2.
I'm going to assume that you have a segue from view controller 1 to view controller 2.
(You should probably have code that disables your send button until all 4 text fields are filled in with valid colors.)
Anyway, let's assume that your send button triggers a segue, either directly, or in an IBAction that triggers a segue through a call to performSegueWithIdentifier.
You need to define properties for your 4 color strings in view controller 2.
Then, add a prepareForSegue method to view controller 1 if you don't have one already. In prepareForSegue, make sure the segue matches the segue identifier that invokes view controller 2 (good idea even if you only have 1 segue now, since you might add more segues later.)
ViewController2 *vc2 = (ViewController2 *) segue.destinationViewController;
Assuming it's the right segue, get a pointer to the destination view controller and cast it to the type of ViewController2 so you can refer to your color properties.
Then use code like this to pass the colors to view controller 2:
vc2.color1 = myColor1TextField.text;
vc2.color2 = myColor2TextField.text;
vc2.color3 = myColor3TextField.text;
vc2.color4 = myColor4TextField.text;

Enable editing mode for tableView when button is pressed

This has probably been asked before but I'm new to iOS Development and when I found confused me. I have a tableView and want to allow the user to tap a button that says "Edit" and they can delete items. I also want the edit button to become a "Done" button, which will stop edit mode. (The user can add data into the tableView from another option, which I will probably need to research how to do.) I don't have a storyboard as I built the app in an app called Interface. Everything is all in code.
The UIViewController class provides a method that gives you the standard Edit/Done button. You can do something like:
self.navigationItem.rightBarButtonItem = [self editButtonItem];
This standard button is setup to call the setEditing:animated: method. When used with a UITableViewController, the table view is automatically toggled between regular and edit mode along with the view controller.
There are plenty of specific table view delegate and data source methods you need to implement on top of this to facilitate actual table editing but using this standard button at least easily lets you toggle in and out of editing mode.
You will need to add the UITableViewDelegate methods.
I presume the 'Done'/'Edit' Button is the same in some place such as your UINavigationBar?
You will have to manually change the title for the button.
Remember to set your ViewController as the delegate for tableview too.
This delegate method informs that you wish to have the table eidtable.
– tableView:editingStyleForRowAtIndexPath:
This method tells you you will start editing:
– tableView:willBeginEditingRowAtIndexPath:
(hint: change button title here)
Likewise this tells you editing is done:
– tableView:didEndEditingRowAtIndexPath:
(hint: change button title here)

iOS keyboard flickers when switching view controllers

I have a registration form and I want to have the keyboard always on top.
The way I'm doing it now, is that when the user moves between view controllers, in viewDidLoad, the first UITextField becomes the first responder.
The problem is that the keyboard flickers (disappears and then appears again) when the user moves between view controllers.
Also, related to this: I have a form with a few uitextfields. When the user presses next it goes to the next uitextfield using becomefirstresponder. When the user is in the last textfield, the keyboard button becomes "Done". Then, when the user presses it, if there's an error with the last field, it should get the focus (calls becomeFirstResponder) but that doesn't happen (nothing get's the focus and the keyboard goes down). All the other fields get the focus fine, just this last field doesn't. I've tried about everything: switching to other textfields and back. The problem is that done automatically removes the keyboard.
You should have made two separate questions for this.
First, your flickering:
I'm guessing you're using a UINavigationController. You can add an invisible UITextField somewhere in the UINavigationController, which you give focus before you switch to a new ViewController. Then, when the new ViewController has appeared (viewDidAppear), set the focus to the first textField as you want.
However, the entire approach is kind of hackey and I don't recommend you use it. Instead, try using several views in a scrollView, of which you change the offset when you move to the new view. This will also solve the flickering.
Second, losing firstResponder status on Done:
The done button is specifically there to indicate exactly that which it says; Done. Pressing this assumes the user is finished and that no text is left to type, thus dismissing the keyboard.
If you really want to keep the Done button, then try the following;
Allow the user to dismiss the keyboard.
Upon dismissal, check for the error in the last field.
If there is an error, instead of calling [lastField becomeFirstResponder], try [self performSelector:#selector(thisSelectorWillCallFirstResponder) withObject:nil afterDelay:1.0].
In the method thisSelectorWillCallFirstResponder call [lastField becomeFirstResponder].
This will give time for the keyboard to disappear, before making it pop up again, so it doesn't interfere with the becomeFirstResponder call.
Another method would be to not use a Done button, but instead use the return key. You can intercept return anytime with the delegate method textFieldShouldReturn:. There you can handle any error checking, without causing the textField to lose its focus.

clearButton not working in UITextEditField

This is one of those "it was working a while ago" troubleshooting efforts.
I'm working on the document preview view controller, in which is a scroll view, which itself contains subclasses of UIView that represent each document. I'm modeling this pretty closely to how Keynote handles its document preview, except I build my scroll view horizontally and with paging. But the standard user experience is present: Long press on a document icon causes all document icons to start jiggling, nab bar has + button and Edit button, etc.
The issue at hand is that when you tap on the name of a document, I hide all the others, move the one being edited front and center, build a new text edit field, add it as a subview atop the real name label, and set it as first responder; but the
[editNameTextField setClearButtonMode:UITextFieldViewModeWhileEditing];
while correctly showing in the edit field is not taking any action when the user taps on the clear button.
I can't figure out what I may have done to cause this to not work -- it had been!
My first thought was that somehow my instance of this subclass is no longer the delegate for this text edit field. To try and confirm/deny that, I usurped a tap on the image view of the document preview to compare the delegate property to self, and it passes.
if (editNameTextField) {
NSLog(#"editNameTextField is still active");
if ([editNameTextField.delegate isEqual:self]) {
NSLog(#"we're still the delegate for the editNameTextField");
}
}
Editing the text within the edit field works fine. Pressing the Return/Done key correctly sends the delegate message textFieldShouldReturn:
While investigating this I implemented the delegate method textFieldShouldClear: just to write a log message if the method gets called (and return YES of course). It never gets called.
My next thought was that perhaps a subview had covered up the area where the clear button sits. So I implemented textFieldShouldBeginEditing: and used the opportunity to bring my the text field to the front. That didn't change anything either. I set a debugger breakpoint there to play a sound when it was called, and it got called, so I know my text edit field is frontmost.
I have only one troubleshooting strategy remaining: Go backwards through snap shots until it starts working again. Before doing that I thought I'd see if any of the more experienced folks out here have any suggestions of what to try next.
Where are you adding the textfield? As a subview of the scrollView? If you added the textfield and it is out of bounds of its parent view it won't receive any touches.
You can try and not call becomeFirstResponder and see if clicking it will show keyboard. Another possible error might be that the parent view of the UITextField has userInteractionEnabled = NO.
Without seeing more code I'm afraid I can not offer more solutions.

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