UIImagePickerController duplicates content on close - ios

Question

When I bring up a UIImagePickerController and then close it, it duplicates the content in my modal window. Below are the before and after pictures:
Here's the code that shows the image picker:
-(void) choosePhotos
{
UIImagePickerController *imagePicker = [[UIImagePickerController alloc] init];
[imagePicker setDelegate:self];
[imagePicker setAllowsEditing:YES];
[imagePicker setSourceType:UIImagePickerControllerSourceTypeCamera];
[self presentViewController:imagePicker animated:YES completion:nil];
}
Here's the rest of my code (if needed):
-(id) init
{
self = [super init];
if (self)
{
[self.navigationItem setTitle:#"Deposit"];
UIBarButtonItem *closeButton = [[UIBarButtonItem alloc] initWithTitle:#"Cancel" style:UIBarButtonItemStyleDone target:self action:#selector(cancel)];
[self.navigationItem setLeftBarButtonItem:closeButton];
toItems = #[#"Account...5544", #"Account...5567"];
UITapGestureRecognizer *recognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(hideKeyboard)];
[self.view addGestureRecognizer:recognizer];
}
return self;
}
-(void) hideKeyboard
{
for (UITextField *field in [scrollView subviews])
{
[field resignFirstResponder];
}
}
-(void) cancel
{
[self.navigationController dismissViewControllerAnimated:YES completion:nil];
}
-(NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView
{
return 1;
}
-(NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component
{
return [toItems count];
}
-(NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component
{
return [toItems objectAtIndex:row];
}
-(void) viewWillAppear:(BOOL)animated
{
[super viewWillAppear:YES];
[self.view setBackgroundColor:[UIColor whiteColor]];
UILabel *toLabel = [[UILabel alloc] initWithFrame:CGRectMake(20, 0, 50, 100)];
[toLabel setText:#"To:"];
toPicker = [[UIPickerView alloc] initWithFrame:CGRectMake(130, -30, 220, 100)];
[toPicker setDataSource:self];
[toPicker setDelegate:self];
UILabel *amountLabel = [[UILabel alloc] initWithFrame:CGRectMake(20, 100, 70, 100)];
amountLabel.lineBreakMode = NSLineBreakByWordWrapping;
amountLabel.numberOfLines = 0;
[amountLabel setText:#"Check Amount:"];
UITextField *amountField = [[UITextField alloc] initWithFrame:CGRectMake(130, 100, 270, 100)];
[amountField setPlaceholder:#"Enter Amount"];
[amountField setReturnKeyType:UIReturnKeyDone];
[amountField setKeyboardType:UIKeyboardTypeDecimalPad];
UILabel *imagesLabel = [[UILabel alloc] initWithFrame:CGRectMake(20, 200, 70, 100)];
imagesLabel.lineBreakMode = NSLineBreakByWordWrapping;
imagesLabel.numberOfLines = 0;
[imagesLabel setText:#"Check Images:"];
UIButton *imagesButton = [[UIButton alloc] initWithFrame:CGRectMake(120, 200, 244, 99)];
[imagesButton setBackgroundImage:[UIImage imageNamed:#"photos.png"] forState:UIControlStateNormal];
[imagesButton addTarget:self action:#selector(choosePhotos) forControlEvents:UIControlEventTouchUpInside];
CGRect bounds = [[UIScreen mainScreen] bounds];
scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, bounds.size.width, bounds.size.height)];
[scrollView setAlwaysBounceVertical:YES];
[scrollView setShowsVerticalScrollIndicator:YES];
[scrollView addSubview:toLabel];
[scrollView addSubview:toPicker];
[scrollView addSubview:amountLabel];
[scrollView addSubview:amountField];
[scrollView addSubview:imagesLabel];
[scrollView addSubview:imagesButton];
[self.view addSubview:scrollView];
}

Answer 1

I recommend you use viewDidLoad as the place to create and add your views:
- (void)viewDidLoad {
[super viewDidLoad];
//init and add your views here
//example view
self.someLabel = [[UILabel alloc] init];
self.someLabel.text = #"someExampleText";
[self.view addSubview:self.someLabel];
}
And either viewWillAppear or viewDidLayoutSubviews as the place to configure their sizes (i prefer viewDidLayoutSubviews so i'll use it as an example):
- (void)viewDidLayoutSubviews {
[super viewDidLayoutSubviews];
self.someLabel.frame = CGRectMake(kMargin,kMargin,kLabelWidth,kLabelHeight);
}
Of course, in order to do this you need to have a reference to all the views you wish to configure this way by creating a property to them in the interface:
#interface YourViewController ()
#property (nonatomic, strong) UILabel *someLabel;
#end;
static CGFloat const kMargin = 20.0f;
static CGFloat const kLabelHeight = 30.0f;
static CGFloat const kLabelWidth = 100.0f;
Also, it is recommended you avoid using hard coded values for their sizes (doing it like CGRectMake(20,20,100,70) but this it not completely wrong.
Not using hard coded values does not mean setting them yourself, it just means to make their values more readable (and on most cases, dynamic).
In my example, i created kMargin, kLabelHeight and kLabelWidth, meaning that anyone who looks at this code will understand what they mean, they will know what to change if needed, and these values can be used in other places.
For example, you could have 4 labels, and in order to keep them all following the same layout rules, all of them will use the kMargin value on the origin.x.
You could also, instead of using a static value for the width, you can implement a dynamic value, like this:
- (void)viewDidLayoutSubviews {
[super viewDidLayoutSubviews];
CGFloat labelWidth = self.view.bounds.size.width - (kMargin * 2);
self.someLabel.frame = CGRectMake(kMargin,kMargin,labelWidth,kLabelHeight);
}
What i did here is to make my label to have the same width as my super view, but i made it account for the left and the right margins (by taking the total view width and reducing twice the margin value).
Since we are doing this on the viewDidLayoutSubviews method, which gets called whenever the superview changes its size (for example, orientation change) this will ensure your UILabel can be shown on any size of view and orientation without extra code to handle 'specific cases'.

Answer 2

Your UI elements are being added to your view every time viewWillAppear is called. This is called when your image picker dismisses and returns to your view, so they're being duplicated. Either check to see whether your UI elements already exist before creating them again, or do your UI setup in the viewDidLoad method which will only be run once. You could try this perhaps, using a BOOL property to keep track:
-(void) viewWillAppear:(BOOL)animated
{
[super viewWillAppear:YES];
if (!self.alreadyAppeared) {
self.alreadyAppeared = YES;
// Create labels and buttons
}
}