I've looked over many online code samples but I couldn't find examples relevant to this particular situation and so I thought I would try asking.
My application is using the utility application template (a main view and a flipside view) with Automatic Reference Counting (ARC) enabled.
On the flipside view, I have an empty UITableView with a navigation bar with a "Done" button, that returns you to the main view, and an "Add" button. Clicking the "Add" button creates an empty row and activates the UIImagePicker. After selecting a photo from the UIImagePicker, that photo is passed into the new row's cell imageView.
My problem is that, after adding a new row to the table, when I switch to the main view then back to the flipside view, the table is empty again.
Since the NSMutableArray resides in FlipviewController, I suspected that the table was getting emptied when FlipviewController (and consequently the NSMutableArray) was unloaded in order to load MainViewController. As such, I tried moving the NSMutableArray to the AppDelegate which prevented the rows from disappearing when switching view controllers, but for some reason the images that I added in each row still disappeared when switching view controllers.
Anyone know what's going on here? Any help would be greatly appreciated!
AppDelegate.h
AppDelegate.m
MainViewController.h
MainViewController.m
FlipsideViewController.h
FlipsideViewController.m
My application is using the utility application template (a main view and a flipside view) with Automatic Reference Counting (ARC) enabled.
On the flipside view, I have an empty UITableView with a navigation bar with a "Done" button, that returns you to the main view, and an "Add" button. Clicking the "Add" button creates an empty row and activates the UIImagePicker. After selecting a photo from the UIImagePicker, that photo is passed into the new row's cell imageView.
My problem is that, after adding a new row to the table, when I switch to the main view then back to the flipside view, the table is empty again.
Since the NSMutableArray resides in FlipviewController, I suspected that the table was getting emptied when FlipviewController (and consequently the NSMutableArray) was unloaded in order to load MainViewController. As such, I tried moving the NSMutableArray to the AppDelegate which prevented the rows from disappearing when switching view controllers, but for some reason the images that I added in each row still disappeared when switching view controllers.
Anyone know what's going on here? Any help would be greatly appreciated!
AppDelegate.h
Code:
#import <UIKit/UIKit.h>
@class MainViewController;
@interface AppDelegate : UIResponder <UIApplicationDelegate>
@property (strong, nonatomic) UIWindow *window;
@property (strong, nonatomic) MainViewController *mainViewController;
@endAppDelegate.m
Code:
#import "AppDelegate.h"
#import "MainViewController.h"
@implementation AppDelegate
@synthesize window = _window;
@synthesize mainViewController = _mainViewController;
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
// Override point for customization after application launch.
self.mainViewController = [[MainViewController alloc] initWithNibName:@"MainViewController" bundle:nil];
self.window.rootViewController = self.mainViewController;
[self.window makeKeyAndVisible];
return YES;
}
- (void)applicationWillResignActive:(UIApplication *)application
{
/*
Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state.
Use this method to pause ongoing tasks, disable timers, and throttle down OpenGL ES frame rates. Games should use this method to pause the game.
*/
}
- (void)applicationDidEnterBackground:(UIApplication *)application
{
/*
Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later.
If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits.
*/
}
- (void)applicationWillEnterForeground:(UIApplication *)application
{
/*
Called as part of the transition from the background to the inactive state; here you can undo many of the changes made on entering the background.
*/
}
- (void)applicationDidBecomeActive:(UIApplication *)application
{
/*
Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface.
*/
}
- (void)applicationWillTerminate:(UIApplication *)application
{
/*
Called when the application is about to terminate.
Save data if appropriate.
See also applicationDidEnterBackground:.
*/
}
@endMainViewController.h
Code:
#import "FlipsideViewController.h"
@interface MainViewController : UIViewController <FlipsideViewControllerDelegate>
- (IBAction)showInfo:(id)sender;
@endMainViewController.m
Code:
#import "MainViewController.h"
@implementation MainViewController
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Release any cached data, images, etc that aren't in use.
}
#pragma mark - View lifecycle
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}
- (void)viewDidUnload
{
[super viewDidUnload];
}
- (void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
}
- (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
}
- (void)viewWillDisappear:(BOOL)animated
{
[super viewWillDisappear:animated];
}
- (void)viewDidDisappear:(BOOL)animated
{
[super viewDidDisappear:animated];
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
// Return YES for supported orientations
return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
}
#pragma mark - Flipside View
- (void)flipsideViewControllerDidFinish:(FlipsideViewController *)controller
{
[self dismissModalViewControllerAnimated:YES];
}
- (IBAction)showInfo:(id)sender
{
FlipsideViewController *controller = [[FlipsideViewController alloc] initWithNibName:@"FlipsideViewController" bundle:nil];
controller.delegate = self;
controller.modalTransitionStyle = UIModalTransitionStyleFlipHorizontal;
[self presentModalViewController:controller animated:YES];
}
@endFlipsideViewController.h
Code:
#import <UIKit/UIKit.h>
@class FlipsideViewController;
@protocol FlipsideViewControllerDelegate
- (void)flipsideViewControllerDidFinish:(FlipsideViewController *)controller;
@end
@interface FlipsideViewController : UIViewController <UIActionSheetDelegate, UIAlertViewDelegate, UIImagePickerControllerDelegate,UINavigationControllerDelegate>
{
NSMutableArray *dataArray;
IBOutlet UITableView *tableView;
IBOutlet UIBarButtonItem *addPhotoButton;
UITableViewCell *addedCell;
UIImage *image;
UIImagePickerController *imagePicker;
}
@property (nonatomic, strong) NSMutableArray *dataArray;
@property (nonatomic, strong) IBOutlet UITableView *tableView;
@property (nonatomic, strong) IBOutlet UIBarButtonItem *addPhotoButton;
@property (nonatomic, strong) UITableViewCell *addedCell;
@property (nonatomic, strong) UIImage *image;
@property (nonatomic, strong) UIImagePickerController *imagePicker;
@property (weak, nonatomic) IBOutlet id <FlipsideViewControllerDelegate> delegate;
- (IBAction)addPhoto:(id)sender;
- (IBAction)done:(id)sender;
@endFlipsideViewController.m
Code:
#import "FlipsideViewController.h"
#import "MainViewController.h"
@implementation FlipsideViewController
@synthesize delegate = _delegate;
@synthesize dataArray, tableView, addPhotoButton, addedCell, image, imagePicker;
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Release any cached data, images, etc that aren't in use.
}
#pragma mark - View lifecycle
- (void)viewDidLoad
{
[super viewDidLoad];
self.dataArray = [[NSMutableArray alloc] init];
self.imagePicker = [[UIImagePickerController alloc] init];
self.imagePicker.allowsEditing = NO;
self.imagePicker.delegate = self;
self.imagePicker.sourceType = UIImagePickerControllerSourceTypePhotoLibrary;
}
#pragma mark - UITableView delegate methods
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return self.dataArray.count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *kCellID = @"cellID";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:kCellID];
if (cell == nil)
{
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:kCellID];
cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
cell.showsReorderControl = YES;
}
return cell;
}
- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
}
- (void)viewWillAppear:(BOOL)animated
{
[super viewWillAppear:animated];
}
- (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
}
- (void)viewWillDisappear:(BOOL)animated
{
[super viewWillDisappear:animated];
}
- (void)viewDidDisappear:(BOOL)animated
{
[super viewDidDisappear:animated];
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
// Return YES for supported orientations
return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
}
#pragma mark - Actions
- (IBAction)addPhoto:(id)sender
{
[self presentModalViewController:self.imagePicker animated:YES];
}
- (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingImage:(UIImage *)img editingInfo:(NSDictionary *)editInfo {
// AppDelegate* appDelegate = (AppDelegate*)[[UIApplication sharedApplication] delegate];
// appDelegate.pickerImage = img;
image = img;
[self dismissModalViewControllerAnimated:YES];
[self.tableView beginUpdates];
[self.dataArray addObject:@""];
NSArray *paths = [NSArray arrayWithObject:[NSIndexPath indexPathForRow:(self.dataArray.count - 1) inSection:0]];
[self.tableView insertRowsAtIndexPaths:paths withRowAnimation:NO];
[self.tableView endUpdates];
addedCell = [self.tableView cellForRowAtIndexPath:[NSIndexPath indexPathForRow:(self.dataArray.count - 1) inSection:0]];
addedCell.imageView.image = image;
[self.tableView reloadData];
}
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {
NSUInteger row = [indexPath row];
[self.dataArray removeObjectAtIndex:row];
[tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationFade];
}
- (IBAction)done:(id)sender
{
[self.delegate flipsideViewControllerDidFinish:self];
}
@end
