I have two views in my application: in main view there are input fields that the user must fill and a button connected to the second view. In the second view there is a table view, when the user selects a row automatically returns to the main view.
My problem is that when you return to the main view the values of text fields are cleared.
Any solutions?
Thank you.
Second View header
#class MainViewController;
#interface ListaViewController : UIViewController
<UITableViewDataSource, UITableViewDelegate, UISearchBarDelegate>
{
UITableView *table;
UISearchBar *search;
MainViewController *child;
}
#property (nonatomic, retain) IBOutlet UITableView *table;
#property (nonatomic, retain) IBOutlet UISearchBar *search;
#property (nonatomic, retain) MainViewController *child;
- (IBAction)switchBack:(id)sender;
Second View Implementation:
-(IBAction)switchBack:(id)sender
{
child.selectedCountry = selectedCountry;
child.codiceComune = codiceComune;
[self.navigationController popViewControllerAnimated:YES];
}
First View:
-(void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
cityField.text = selectedCountry;
}
This not work!
-(IBAction)switchBack:(id)sender
{
MainViewController *controller = [[MainViewController alloc] initWithNibName:#"MainViewController" bundle:nil];
controller.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
[self presentModalViewController:controller animated: YES];
[controller release];
}
It means you create new MainViewController, not return to previous.
Use this code instead
-(IBAction)switchBack:(id)sender
{
[self dismissModalViewControllerAnimated:YES];
}
P.S. It works if you go to the second vievcontroller same way, as you write in -(IBAction)switchBack:(id)sender
As a guess without code, you're probably emptying or initialising your text fields in viewDidLoad, viewDidAppear or viewWillappear - do it in your viewController init instead.
Related
Here is my situation. I have ViewController class A with a button that goes to TableViewController class B by doing the following.
- (void) goToClassB
{
ViewControllerB *viewController =
[[ViewControllerB alloc] initWithStyle:UITableViewStylePlain];
// Present view controller modally.
if ([self
respondsToSelector:#selector(presentViewController:animated:completion:)]) {
[self presentViewController:viewController animated:YES completion:nil];
} else {
[self presentModalViewController:viewController animated:YES];
}
}
I want to be able to have an array that can be accessed and edited by both class A and class B. How can I achieve this?
Create a Array variable in Class B like:
#interface classB:NSObject
{
NSMutableArray *arrayFromA;
}
#property (nonatomic, assign) NSMutableArray *arrayFromA;
Synthesize the variable.
And in this method pass the array like:
- (void) goToClassB
{
ViewControllerB *viewController = [[ViewControllerB alloc] initWithStyle:UITableViewStylePlain];
[viewController setArrayFromA:yourArray];
// Present view controller modally.
if ([self
respondsToSelector:#selector(presentViewController:animated:completion:)])
{
[self presentViewController:viewController animated:YES completion:nil];
}
else
{
[self presentModalViewController:viewController animated:YES];
}
}
Create a NSMutableArray in ViewControllerA and pass it to ViewControllerB after your allocation.
This can be achieve Creating NSMutableArray And And Make it in Property assign in one of the class
#property(nonatomic,assign) NSMutableArray *array;
I mention that you want edit by both so.You can use application delegation for sharing app level variable. Check this link.
Some code is here. In your app delegate class.
#interface YourDelegateClass:UIResponder
{
NSMutableArray *array;
}
#property (nonatomic, assign) NSMutableArray *array;
You can access that array from everywhere of your app class with this code
YourDelegateClass * delegate =[[UIApplication shareApplication]delegate];
yourclassa.array = delegate.array;
or yourclassb.array = delegate.array;
Note: your must alloc *delegate.array* on your prefer at class or your delegate.
Create NSMutable array in view1 set property
#property(nonatomic,assign) NSMutableArray *array;
Create same array in viewB and set property and
#property (nonatomic, assign) NSMutableArray *arrayB;
#Synthesize that
Now at the time call viewB set value of array of viewA to viewB like this
ViewControllerB *viewController = [[ViewControllerB alloc] initWithStyle:UITableViewStylePlain];
[viewController arrayB:array];
The simplest way would, just as others point out, be simply passing the array to B by setting a property, but one other option would be to let B have a weak back reference to A. Thus you're always using the same array. This could be useful if A and B are changing the array at the same time.
#interface ViewControllerA : UIViewController
#property (nonatomic, strong) NSArray *array;
#end
#interface ViewControllerB : UIViewController
#property (nonatomic, weak) ViewControllerA *viewControllerA;
#end
/* When you're creating the ViewControllerB, do this: */
...
viewController.viewControllerA = self;
...
/* Use the array (From ViewControllerB) */
- (void)doSomethingWithTheArray
{
self.viewControllerA.array = ...
}
i am using UITabBar to display two viewControllers, firstViewController is a uiview and secondViewController is a table view. what my need is when i clicked the second view table cell, the value should be updated on UILabel of firstViewController.
my code is here,
In secondviewcontroller.h
#interface firstviewcontroller {
NSMutableArray *stationnamestobepassed;
}
#property (nonatomic, retain) NSMutableArray *stationnamestobepassed;
#end
In secondviewcontroller.m declare this
#implementation firstviewcontroller
#synthesize stationnamestobepassed;
-(void) someaction{
stationnamestobepassed = [NSMutableArray
arrayWithObjects:#"string1",#"string2",#"string3"];
secondviewcontroller = [[secondviewcontroller alloc]initWithNibName:#"NIbName"
Bundle:nil];
secondviewcontroller.stationnamespassed = self.stationnamestobepassed;
//i am not pushing the view controller.
}
#end
In firstviewcontroller.h declare this
#interface secondviewcontroller {
NSMutableArray *stationnamespassed;
}
#property (nonatomic, retain) NSMutableArray *stationnamespassed;
#end
In firstviewcontroller.m declare this
#implementation secondviewcontroller
#synthesize stationnamespassed;
-(void)viewWillAppear:(BOOL)animated
{
//stationNameDisplay is a uilabel
stationNameDisplay.text=[stationnamespassed objectAtIndex:0];
NSLog(#"station name %#",[stationnamespassed objectAtIndex:0]);
}
-(void) dealloc{
[stationnamespassed release];
[super release];
}
#end
problem is , value is not updating and it gives NULL. but i tried with pushing the first vie and it works. actually i don't want to push that view controller because i was already exist on tab.
your view will appear called out when you select the tab. while this line makes a new object of that controller, not that of tab controller.
secondviewcontroller = [[secondviewcontroller alloc]initWithNibName:#"NIbName"
Bundle:nil];
to do what you want. you will have to do some thing like this
UINavigationController* navController = [[self.tabBarController viewControllers] objectAtIndex:/*your tab index on which desiredControllerResides*/];
NSArray* viewControllers= [navController viewControllers];
for(UIViewController *theController in viewControllers)
{
if([theController isKindOfClass:[secondviewcontroller]])
{
theController.stationnamespassed = self.stationnamestobepassed;
//i.e this line of your code secondviewcontroller.stationnamespassed = self.stationnamestobepassed;
}
}
I cannot seem to find this anywhere online. I have an add button in one of my views and I have hooked it up to an IBAction method called add. In my storyboard, I have created a view that has a form all set up on it. I have assigned a class to that view in the storyboard as well. That class is called AddItemViewController.
I am trying to present this view modally and then set the delegate to the view that called the AddItemViewController. However, all I get is an empty UITableViewController that shows up. Here is my code that I'm trying to use:
- (IBAction)add {
AddItemViewController *addItem = [[AddItemViewController alloc] init];
addItem.delegate = self;
[self presentModalViewController:addItem animated:YES];
}
Is there anything I'm missing? Why does it just show an empty table and not the view controller that I set up in the storyboard?
Here is the code from the AddItemViewController:
#interface AddItemViewController : UITableViewController <UITextFieldDelegate> {
}
#property (strong, nonatomic) IBOutlet UITextField *note;
- (void)save:(id)sender;
- (void)cancel:(id)sender;
#end
#implementation AddItemViewController
- (void)viewDidLoad {
}
- (IBAction)cancel:(id)sender {
[self dismissViewControllerAnimated:YES completion:nil];
}
- (IBAction)save:(id)sender {
DbHandler *db = [[DbHandler alloc] init];
[db executeUpdate:self.note];
[self dismissViewControllerAnimated:YES completion:nil];
}
#end
Well, AddItemViewController inherits from UITableViewController, not UIViewController, so it makes sense that a UITableViewController is showing up.
You should initiate the AddItemViewController like this:
AddItemViewController *addItem = [[AddItemViewController alloc] initWithNibName:#"AddItemViewController"];
I have an existing TableViewController as follows
// TableViewController.h
#interface TableViewController : UITableViewController { NSArray *dataArray; }
#property (nonatomic, retain) NSArray *dataArray;
And a navAppDelegate - to be specific:
// navAppDelegate.h
#import <UIKit/UIKit.h>
#interface navwAppDelegate : NSObject
<UIApplicationDelegate, UINavigationControllerDelegate> {
UIWindow *window;
IBOutlet UINavigationController *navigationController;}
#property (nonatomic, retain) IBOutlet UIWindow *window;
#property (nonatomic, retain) UINavigationController *navigationController;
// navAppDelegate.m
#import "navAppDelegate.h"
#implementation navigationtableviewAppDelegate
#synthesize window, navigationController;
- (void)applicationDidFinishLaunching:(UIApplication *)application
{
[window makeKeyAndVisible];
[window addSubview:[navigationController view]];
}
Now, I simply added the files to an existing project, except I put the content of (void)applicationDidFinishLaunching{} in a (void)viewDidLoad{} since it's a view from now on and not a window (right?). It doesn't work and my guess is that I have to change all the window calls from above to a view? What am I making here fundamentally wrong?
I'm making a call from
// StartOffHere.m
- (void)LetsGoButtonTouched {
navAppDelegate *newview = [[navAppDelegate alloc] initWithNibName:nil bundle:nil]; // I get a SIGABRT here
[[self navigationController] pushViewController: newview animated: YES];
}
- (void)LetsGoButtonTouched {
TableViewController *tableViewController = [[TableViewController alloc] init];
[[self navigationController] pushViewController:tableViewController animated: YES];
}
Try that. Is that what you wanted to happen?
If so, what I have done is created a new instance of your table view controller and pushed that. In your original code, you were trying to push on the app delegate which cannot be done; the app delegate is not a view controller. TableViewController, your subclass of UITableViewController, is though, so you can use this for the pushViewController: method - and the table view will appear on screen.
Thanks Benjamin. Excellent. But it didn't work quite that way though - after two hard days I managed it to run. For those who are interesed, here's what I did:
If you want to add an existing TableViewController with a NavigationController you'll only need the TableViewController and the DetailViewController files. Forget the AppDelegate.
Do twice new file -> Subclass and copy your existing code into identical TableViewController .h/.m/.xib - and DetailViewController .h/.m/.xib respectively.
When you make the method call you have to integrate both the TableViewController and the NavigationController - like this:
- (void)LetsGoButtonTouched {
TableViewController *tvc = [[[TableViewController alloc] init] autorelease];
UINavigationController *navigationController = [[[UINavigationController alloc] initWithRootViewController:tvc]autorelease];
[self presentModalViewController:navigationController animated:YES];
By the way, this question gave me the hint:
Add a UINavigationBar to a UITableViewController without a UINavigationController
To begin, I would like to apologize for my English :)
I have FirstViewController, which contains scrollView. This is scrolView with enabled paging, and have 2 pages with 2 different view controllers. From one of the view controllers by touching the button the third view controller appears like a modal view. I call a method in FirstViewController that must disable scrolling and hide two labels which is not contained in the scrollView.
Method is executing, but UI not changes, scrolling still enabled and labels still visible.
Now a bit of code:
This is a piece of the FirstViewController.h (not the whole code):
#interface FirstViewController : UIViewController <UIScrollViewDelegate> {
IBOutlet UIScrollView *scrollView;
IBOutlet UILabel *label1;
IBOutlet UILabel *label2;
}
#property (nonatomic, retain) UILabel *label1;
#property (nonatomic, retain) UILabel *label2;
#property (nonatomic, retain) UIScrollView *scrollView;
-(void)prepareToModal;
#end
Now it's -(void)prepareToModal; implementation:
-(void)prepareToModal {
[label1 setHidden:YES];
[label2 setHidden:YES];
scrollView.scrollEnabled = NO;
}
So, from the one of the view controllers, which contained in scrollView, I call prepareToModal
Previously:
#import "FirstViewController.h"
Next:
FirstViewController *vc = [[FirstViewController alloc] init];
[vc prepareToModal];
[vc release];
So, that's all. I put a breakpoint in prepareToModal, and it stopped executing. The method is called, but nothing changes on screen...
What am I doing wrong?
How to do this correctly?
Update:
I solved this problem.
When I present this modal view, I wrote this:
ThirdViewController *tvc = [[ThirdViewControler alloc] init];
tvc.delegate = self;
UINavigationController *nc = [[UINavigationController alloc] initWithRootViewController:tvc];
[self presentModalViewController:nc animated:YES];
[tvc release];
[nc release];
Now, insted of [self presentModalViewController:nc animated:YES]; I write this:
[[[[UIApplication sharedApplication].windows objectAtIndex:0] rootViewController] presentModalViewController:nc animated:YES];
And It's working very well, I don't need a method -(void)prepareToModal;
Thanks a lot :)
Make sure you have hooked up your IBOutlets in Interface Builder.