iOS/Xcode - Multiple segue identifiers resetting data parsing - ios

So I got a ViewController with 4 seperate buttons. When clicking on button1 TableViewController1 pops over the ViewController with a list of items. When selecting an item the TableViewController1 drops down and button1 now has the text that was selected in the table. This is all good. But when I do the exact same thing for button2 with TableViewController2 the data from button1 is reseted.
I use segues with identifiers, some of the code:
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
if ([segue.identifier isEqualToString:#"showEducation"]) {
NSIndexPath *indexPath = [self.tableViewEducation indexPathForSelectedRow];
ViewController *destViewController = segue.destinationViewController;
destViewController.educationText = [tableViewArray objectAtIndex:indexPath.row];
}
}
So at the moment I got multiple segue identifiers for each button and multiple .h and .m files for the tableviews. Am I using a completely wrong technique to get this to work? I hope im clear enough, otherwise I can upload images.
Edit: I just noticed, I also have a slider on my ViewController. When clicking on a button and selecting a row in the TableView the slider gets reseted to the original position. Same problem as above kind of.

I am thinking that you're pushing to a new instance of your View Controller every time you push from either tableViewController.
Imagine that you click on one button on ViewController0, this creates an instance of tableViewController1. When you click a row, you're just using a performSegue to create a NEW instance of ViewController0, and this has its own ViewDidLoad - resetting the buttons.
(You're saying that the view "drops down", so it's modal?)
Don't use performSegue from the tableViewController back to the viewController, try using [self dismissModalViewController: withCompletion:](or something similar, can't remember), then your tableViewController should remove itself and reveal the original ViewController.
Now, you don't have a way to change the name of the button though, but that can be done by accessing the sender from the tableView, which will give you the original View Controller, and not a new instance of it.
One way of getting the sender is to use [performSegue... from ViewController0, and in it's own prepareForSegue, you could do something like
//In the first ViewController, not in the TableViewControllers
-(void)prepareForSegue:(UIStoryboardSegue*)segue sender:(id)sender{
if(sender == button1)
{
UITableViewController1 *dest = segue.destinationViewController;
[dest setSender: self];
}
}
And in TableViewController1 you'd create a variable ViewController *home;, and a method -(void)setSender:(ViewController*)sender;, so that in your didSelectRowAtIndexPath, you could now say [[(ViewController0*)home button1]setTitle:#..];, and then [dismissModalViewController..]
There are other ways to do it as well, depending on how you are pushing from your viewController to the tableViewController. And I'm sure there are easier ways to access the sender than this, but it works and is useful if you're already sending other data.

Related

Adding row to the TableView when Button action

I have two ViewControls.
In FirstViewControl i have button and,
In SecondViewControl i have TableView,
When i click on button it should go to the TableView(SecondViewControl) and add one row ,how can i do it with programatically.I did not getting sufficient answers.Can any one help me
First thing that you should do is to create an NSMutableArray property in FirstViewController. That array needs to be filled in with all data that will be displayed on SecondViewController.
#property (nonatomic, strong) NSMutableArray *arrayOfData;
Also create a NSMutableArray property in SecondViewController. Now when you have two properties that are capable of holding data, you can go to step when Button is pressed.
- (IBAction)buttonInCellPressed:(UIButton *)sender {
[arrayOdData addObject:#"E.g. some string.";
// Call transition to second view after button is clicked
[self performSegueWithIdentifier: #"GoToSecondViewController" sender: self];
}
Code above will add new element to the array, based on what you want to add you will need some customization. Once perform segue is called you will need to copy data before view is actually displayed. You will do that in prepareForSegue method.
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
// This string needs to be equal to one that you put in performSegue and on that is in storyboard
if ([[segue identifier] isEqualToString:#"GoToSecondViewController"])
{
SecondViewController *vc = [segue destinationViewController];
// This is array in second view controller
vc.arrayOfData = [NSMutableArray arrayWithArray:oldArray];
}
}
Now in the new controller, use arrayOfData to fill in TableView. Also, for this solution you will need to return array to the first controller, same process as you did when you send it to second one.
If you want to improve your code, you will need to implement some object that will hold data separately from views.

UICollectionView Segue not showing detail VC

I have 2 view controllers - One with a collectionView displaying images, the other it's corresponding detail view - pretty basic. The problems is items in collectionView are not selectable for some reason (touch but nothing happens). Also, I am not using a nav controller to embed the collectionView VC in, prefer to use an unwind segue with custom button - will this work?
I made a connection from the collectionView Cell to the Detail VC.
In prepareForSegue
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
if ([segue.identifier isEqualToString:#"detailSegue"]) {
LPDiaryDetailViewController *destViewController = segue.destinationViewController;
NSIndexPath *indexPath = [self.collectionView indexPathForCell:sender];
LocationImage *image = self.savedItems[indexPath.row];
destViewController.captionString = image.caption;
}
}
The cell is probably not responding to touches because you haven't set the image view's userInteractionEnabled property to YES (it's NO by default).
You can't use an unwind segue to go forward; they're for going back to a previous controller, so your preference to use an unwind segue doesn't make sense. Do you mean for the unwind segue to be used for going back from the detail VC? It's not clear where you want this custom button. You already have the segue connected from the cell, so you don't need a button to invoke the segue.

How can i hold the value of a string when the viewController goes to another tableViewController

Well, that question sure sounds weird but i couldn't find a better way to put it.
I m pretty sure its a basic mistake but i m stuck.
I got a main home view controller, there are 2 buttons which leads to 2 different tableViewController.
i will use both of the selections.
But when i get the selected index from one table view and go the the next one, the first one's value become null.
if (tempFromLocationString!=NULL) {
//tempFromLocationString=#"asd";
fromLocationLabel.text=tempFromLocationString;
}
if (tempToLocationString!=NULL) {
toLocationLabel.text=tempToLocationString;
}
this is how i segue from tableView to View controller
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if ([[segue identifier] isEqualToString:#"fromLocationSegue"])
{
NSLog(#"%#",selectionString);
ViewController *vc = [segue destinationViewController];
vc.tempFromLocationString=selectionString;
}
}
and this is how i get the selected cell's value.
- (void) tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{
selectionString=[fromLocationArray objectAtIndex:indexPath.row];
NSLog(#"%#",selectionString);
}
this is my code. i get temp strings with segues and i m applying these codes in view did load.
all the NSStrings declared in .h files.
the flow is like this;
user enter the app,
select a button,
goes to the first table view controller
select a location,
clicks ok button and goes back to the first view controller with segue ( selectionString)
the label is set to the selectionString appropriately
user click next button,
goes to the select table view
select a location
clicks ok and goes back the first view controller now the second label is set to the selectionString appropriately but now the first one is deleted and the string become null
OK
Your app flow
Case1
User enter the app - Correct
Select a button - Correct
Goes to the First TableViewController select a location -
Correct
Clicks ok button - Correct
and Goes back to the first view controller with segue
(selectionString) the label is set to the selectionString
appropriately - Incorrect
Step 5 is incorrect, why?
Answer - Because you are again pushing the ViewController after the selection in tableViewController, where as your ViewController already exist in the stack, so here instead of using segue, you should just pop the viewcontroller with same reference taken from ViewController.
Case2
User click next button - Correct
Goes to the select table view select a location clicks ok - Correct
and goes back the first view controller now the second label is set to the selectionString appropriately but now the first one is deleted and the string become null - Incorrect
Step 3 is incorrect the same way as Case1.
Answer- Again you are actually not going back, you are going forward, so what happens is you are creating a new instance of ViewController on selection, which doesn't have the previous selected value.
Solution
Create NSString property in each respective tableViewController separately same as you have in ViewController.
When you segue tableViewController from ViewController, assign the property like
TableViewController *vc = [segue destinationViewController];
vc.tempFromLocationString=self.tempFromLocationString;
On selection in tableviewcontroller do the following
self.tempFromLocationString=selectionString;
[self.navigationController popViewController:YES];
Now instead of assigning value in ViewDidLoad in ViewController, do it in ViewWillAppear.
I hope it helps.
Maybe your strings are not NULL when you set your labels.
Try to put a breakpoint before those lines, and check your temp strings
if (tempFromLocationString!=NULL) {
//tempFromLocationString=#"asd";
fromLocationLabel.text=tempFromLocationString;
}
if (tempToLocationString!=NULL) {
toLocationLabel.text=tempToLocationString;
}
If they are not NULL try this:
if (tempFromLocationString && [tempFromLocationString length] > 0) {
fromLocationLabel.text=tempFromLocationString;
}

iOS segue executed twice

I have a table view with different types of table view cells in it. In one of the cells, there are two buttons, which load a view controller when pressed. I am using the following function to handle the button press:
- (IBAction)leftButtonPressed:(id)sender
{
// Getting the pressed button
UIButton *button = (UIButton*)sender;
// Getting the indexpath
NSIndexPath *indPath = [NSIndexPath indexPathForRow:button.tag inSection:0];
// Loading the proper data from my datasource
NSArray *clickedEvent = [[[SOEventManager sharedEventManager] eventsArray] objectAtIndex:indPath.row];
[[SOEventManager sharedEventManager] setSelectedEvent:clickedEvent[0]];
// Everything working as it should up to this point
// Performing seque...
[self performSegueWithIdentifier:#"buttonSegue" sender:self];
}
My buttonSegue is supposed to push a new view controller. Somehow instead of pushing once, it appears to be pushing twice, so I get the following warning:
2013-11-27 01:48:30.894 Self-Ordering App[2081:70b] nested push animation can result in corrupted navigation bar
2013-11-27 01:48:31.570 Self-Ordering App[2081:70b] Finishing up a navigation transition in an unexpected state. Navigation Bar subview tree might get corrupted.
In my case it leads to a crash, since there is an event in which I want the app to immediately pop the view controller so it an go back to my table view. I use an alertview for this and handle the event with the following:
- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
NSString *buttonTitle = [alertView buttonTitleAtIndex:buttonIndex];
// ...
// Additional checking of button titles....
else if ([buttonTitle isEqualToString:NSLocalizedString(#"Vissza", nil)])
{
[self.navigationController popViewControllerAnimated:YES];
}
}
It might me interesting to note that I have an other segue from my "regular" table view cell, and in that case I use the prepareForSegue: method
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if ([segue.identifier isEqualToString:#"detailSegue"])
{
NSIndexPath *indexPath = [self.tableView indexPathForSelectedRow];
SOEvent *selectedEvent = [[[SOEventManager sharedEventManager] eventsArray] objectAtIndex:indexPath.row];
[[SOEventManager sharedEventManager] setSelectedEvent:selectedEvent];
}
}
In this case the view controller gets pushed perfectly, and even popped immediately if that is required. I am testing this on iOS7 and Xcode 5. I haven't encountered a problem like this before, any help would be greatly appreciated.
Maybe you want to wire up your segues with View Controllers instead of UIButtons!
You should probably have the segues wired with some button like this:
But you should wire them with the view controllers instead:
Answer by can poyrazoğlu:
are you sure you've wired up the actions correctly in interface
builder? maybe you've wired the event for, say, both touch up inside
and touch down inside instead of just touch up inside. or maybe you've
also assigned the segue from both code and again in interface builder.
have you checked them? it's a common mistake. –
I was assigning the touch up inside actions for each button both the storyboard and my tableview's datasource methods.
Thank you for your quick help can poyrazoğlu!!
For Swift 3, xcode, and ios 9+, which is what I am using: Make sure you are drawing segue from your UIViewControllers and not buttons or other interfaces.
I had the same problem, and simply changing the start of the segue from the UIController instead of the button removed this bug.
I always get this issue when I have my buttons directly wired up to the destination view controller. You need to make sure that you first delete the old segue you made, then click on the present view controller (where you are coming from) and CTRL + click to destination controller.
This should fix it :)

Conditional Segue navigation from UITableViewCell based on response to UIAlertView

My problem seems like a generic problem, yet can't seem to find an answer for it.
I have a situation where when the user taps on a custom UITableViewCell, I would like to display an alert and then based on the response to the alert, either stay on the same view (user selecting cancel) or display another view (if the user selects proceed). And I would like to do this using the storyboard feature & segues.
How would one go about this? Do you have to do this the old fashioned way?
#user, Just create the alertView the old fashion way; I do know of any storyboard feature to do this differently. Where storyboard can help is with the segues. You can call the segues programmatically. With you alert view cancel button you can just return (i.e. do nothing). For the other option, to display another view, you can programmatically call a segue to transition to the desired view. If you don't have the proper segue already defined for some other reason on your storyboard, just create a button out and use that to create the segue and name it. Name the segue by clicking on it in storyboard and use the attributes inspector to give it name (identifier). Then hide the button or put it out of the view. I typically put these type of button on the toolbar and use spacers to keep them out of the view. Here's some sample code:
Call the segue from the alert view delegate like this:
[self performSegueWithIdentifier: #"done" sender: self];
Also implement this method to do any necessary task to prepare for the segue:
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
if ([[segue identifier] isEqualToString:#"done"])
{
// [[segue destinationViewController] setManagedObjectContext:self.managedObjectContext];
// [[segue destinationViewController] setSelectedClient:selectedClient];
}
}
You can create segues directly from the startingViewController to multiple destinationViewControllers that can then be "performed" programmatically. You do not need to create any hidden buttons for them, which does seem like a hack.
OK I came up with a solution in keeping with the storyboard that I like.
Example:
My tableview has 2 sections, grouped, and cells are dynamic prototype. Section 0 contains one row/UITableViewCell & I don't want it to segue. Section 1 contains multiple cells that I want to trigger the segue & drill down into the detail.
In Storyboard:
I removed the segue linking the tableviewcell to the destination view controller.
I made a 'generic' segue linking the source view controller directly to the destination view controller.
In the attributes on the segue, I set the identifier ('EditTimePeriod') and set the type to Push (I presume Modal would work just the same).
In the source view controller:
In the prepareForSegue method I handled both the common 'AddTimePeriod' segue I control-dragged from my UIBarButtonItem (Add), along with the 'generic'(vc-->vc) 'EditTimePeriod' segue.
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
// handle the click of the 'Add' bar button item
if([segue.identifier isEqualToString:#"AddTimePeriod"]) {
TimePeriodViewController* tpvc = (TimePeriodViewController*)segue.destinationViewController;
tpvc.delegate = self;
// database & entity stuff for adding the new one to the mOC, etc
}
// handle the click of one of the 'editable' cells -
if([segue.identifier isEqualToString:#"EditTimePeriod"]) {
TimePeriodViewController* tpvc = (TimePeriodViewController*)segue.destinationViewController;
tpvc.delegate = self;
TimePeriod * newTP = [self.timePeriodArray objectAtIndex:self.tableView.indexPathForSelectedRow.row];
tpvc.timePeriod = newTP;
}
}
Then I implemented the tableView:didSelectRowAtIndexPath method, and put my condition in here. If the selected row was outside of section zero I called the EditTimePeriod segue manually, defining the sender as the selected tableviewcell:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
if(self.tableView.indexPathForSelectedRow.section!=0){
[self performSegueWithIdentifier:#"EditTimePeriod" sender:[tableView cellForRowAtIndexPath:indexPath]];
}
[self.tableView deselectRowAtIndexPath:indexPath animated:YES];
return;
}
would be nice to code the cell in section 0 so that it is not selectable in the first place!
Hope this helps though.
** and then 5 minutes later I took another look and realized I could just move the data from section 0 into the section header, which is more intuitive and wasn't being used anyway. leaving the design open for a standard segue from each tableviewcell without needing any condition/check. Was a good exercise anyway though :)

Resources