Passing a UIImage to a SubView's UIImageView? - ios

I'm trying to pass a UIImage value to a UIImageView inside a View that I'm adding as a subView.
Here's what I'm doing in my mainViewController:
- (IBAction)selectStore:(id)sender {
StoreSelectorViewController *SSVC = [[StoreSelectorViewController alloc] initWithNibName:#"StoreSelectorViewController" bundle:nil];
[self.navigationController addChildViewController:SSVC];
[SSVC.backgroundView setImage:[UIImage imageNamed:#"CoolBG.png"]];
[self.view.window addSubview:SSVC.view];
}
I did the following in my StoreSelectorViewController.h file:
#property (nonatomic, retain) IBOutlet UIImageView *backgroundView;
And I also linked it in the XIB file.
Everything loads, except that I never receive the UIImage value. Thanks

Sometimes using this doesn't seem to work:
[SSVC.backgroundView setImage:[UIImage imageNamed:#"CoolBG.png"]];
So instead I use this two line version, in a slightly dif't order, setting the image, before displaying its parent (SSVC):
StoreSelectorViewController *SSVC = [[StoreSelectorViewController alloc] initWithNibName:#"StoreSelectorViewController" bundle:nil];
UIImage *img = [UIImage imageNamed:#"CoolBG.png"];
[SSVC.backgroundView setImage:img];
[self.navigationController addChildViewController:SSVC];
[self.view.window addSubview:SSVC.view];

You really shouldn't be calling addChildViewController regardless, it's not what you want. You're not making use of the UIViewController either, just stealing its view property. It's possible that because of this, the UIViewController is not fully instantiated since it's not presented (viewWill/Did) methods never get called, and so backgroundView is probably nil.

The problem is in this line [self.view.window addSubview:SSVC.view]; So just replace the line to below:-
Also you want to add imageview as a subview of view. So use below code where backgroundView is the imageview:-
[SSVC.view addSubview:SSVC.backgroundView];
[self.view addSubview:SSVC.view];.

Related

uiimageview addSubView not working as intended?

I have an uiImageview which is intended to use in multiple viewControllers.
What I am thinking is an independant UiImageview that can bind and
unbind from viewController to viewController if needed.
Here is my bind/ unbind part of code.
#synthesize uiImgView1;
-(void) sendUIObjToViewController : (UIImageView*)imgView : (UIViewController*)vController{
[vController.view addSubview:imgView];
}
-(UIImageView*)constructUiImgView : (NSString*) imgAddress{
UIImageView *imgView = [[UIImageView alloc] initWithFrame : CGRectMake(50,50,100,100)];
[imgView setImage:[UIImage imageNamed:imgAddress]];
return imgView;
}
-(void) construct : (UIViewController*) vController{
uiImgView1 = [self constructImgView : #"abc.png"];
[self sendUIObjToViewController : uiImgView1 : vController];
}
If I call addSubView method from scope of constructUiImgView,
addSubView works.
-(UIImageView*)constructUiImgView : (NSString*) imgAddress : (viewController*)vController{
UIImageView *imgView = [[UIImageView alloc] initWithFrame : CGRectMake(50,50,100,100)];
[imgView setImage:[UIImage imageNamed:imgAddress]];
[vController.view addSubView imgView];
return imgView;
}
However, that means constructed uiImageView is depandant to one
specific viewController and I don't want to do that.
and If I call sendUiObjToViewController method, uiImageView
should bind to view of viewController but not works.
Am I doing some mistake of referencing variable or something??
My knowledge of Object-c is very limited so I really
need you guys help. Could you tell me what is wrong with my code?
any help will be appreciated.

UIImageView set image programmatically bug

I have a UIImageView in a storyboard, connected to the header of the subclassed UIViewController like this:
#property (retain, nonatomic) IBOutlet UIImageView *displayPhoto;
In the .m of the UIViewController subclass, I try to set the image of the displayPhoto.
#synthesize displayPhoto;
-(void)awakeFromNib {
UIImage *image = [UIImage imageNamed:#"dp.jpg"];
[displayPhoto setImage:image];
displayPhoto.layer.cornerRadius = displayPhoto.image.size.width/2;
[self.view addSubview:displayPhoto];
}
but it does absolutely nothing. If I add one more line, adding another view of the image like so: [self.view addSubview:[[UIImageView alloc] initWithImage:image]];, making my methodf
#synthesize displayPhoto;
-(void)awakeFromNib {
UIImage *image = [UIImage imageNamed:#"dp.jpg"];
[self.view addSubview:[[UIImageView alloc] initWithImage:image]];
[displayPhoto setImage:image];
displayPhoto.layer.cornerRadius = displayPhoto.image.size.width/2;
[self.view addSubview:displayPhoto];
}
It suddenly starts working and adds to instances of the image to the view. One in the top left corner (from the line I added) and a second in the storyboard image location.
What's changing? How is adding that one line making my code work and is there any work around so I can make the image just show up as normal?
If you added the UIImage in your storyboard and connected the outlet correctly, there is no need to create a new image programmatically. Try this.
- (void) viewDidLoad {
[super viewDidLoad];
self.displayPhoto.image = [UIImage imageNamed:#"dp.jpg"];
}
Check the connection of imageview to storyboard will solve your problem.
Use this:
self.imgObj.image=[UIImage imageNamed:#"Your string"];

Why setNeedsDisplay required when initWithNibName used

I have custom UIViewController class called MSPageViewController with and associated nib file. I have an IBOutlet which is a UIImageView called pageImage.
Now, I want to use this view controller in another UIViewController which will display a series of my custom MSPageViewController in a UIPageViewController. So, I use the following code:
// alloc and init my custom view controller
MSPageViewController *page1 = [[MSPageViewController alloc] initWithNibName:#"MSPageViewController" bundle:nil];
// I must call this or, the image that I set below will always be null
// why? I guess it's because the view hasn't been drawn yet because it hasn't been displayed, so I need to force the redraw - but this is my question. Is this is the right approach?
[page1.view setNeedsDisplay];
// set the image
page1.pageImage.image = [UIImage imageNamed:#"tutorialPage1.png"];
// make my array of view controllers, it expects an array because could be double-sided
NSArray *viewController = [NSArray page1];
// pass the array that contains my custom view controller
[self.pageController setViewControllers:viewController direction:UIPageViewControllerNavigationDirectionForward animated:NO completion:nil];
So am I doing this right? I have to force the redraw so that my outlets exist when I try to assign to them?
It's not the setNeedsDisplay part that you "need", it's the self.view part. By accessing the view property you are forcing the view controller to actually load the NIB. I guess that as a side effect of this, the pageImage property is populated as well (and was nil before you called self.view).
So, just calling self.view; instead of [self.view setNeedsDisplay]; should be enough.
As others have noted, pageImage (a UIImageView?) is likely not loaded from the nib yet when you're accessing it.
If you have a custom getter for pageImage, you could do the following:
- (UIImageView*) pageImage
{
[self view];
return _pageImage; // assuming the property backing ivar is synthesized as _pageImage.
}
But my personal preference would be to not expose the imageview itself and just expose a property for image. Then you can set the image to the viewcontroller regardless of it's loaded state, and internally set it to the imageView once the view loads:
- (void) setImage: (UIImage*) image
{
_image = image;
if ( self.isViewLoaded )
{
self.pageImage.image = image;
}
}
- (void) viewDidLoad
{
[super viewDidLoad];
self.pageImage.image = self.image;
}
If you moved some code to the viewDidLoad method you would be guaranteed that the view had been drawn.

iOS - passing Sender (button) name to addSubview

I have a main view with 3 buttons. Clicking on any of the buttons adds a SubView.
The buttons have different titles and are all linked to IBAction "switchView"
The "switchView" code is below.
- (IBAction)switchView:(id)sender{
secondView *myViewController = [[secondView alloc] initWithNibName:#"secondView" bundle:nil];
[self.view addSubview:myViewController.view];
}
The "secondView" loads up correctly and everything works well.
The problem is I want to be able to know which button was the Sender.
I don't want to create 3 subviews, one for each button. The code and XIB would be absolutely the same>
The only difference would be a variable that I would like to set up in the second view (viewDidLoad method) depending on who is the Sender (which button was clicked)
Is this possible? Or I would need to create 3 subViews - one for each button?
Your help is greatly appreciated!
You can identify different buttons with the tag property.
e.g. with your method:
-(IBAction)switchView:(id)sender {
UIButton *button = (UIButton*)sender;
if (button.tag == 1) {
//TODO: Code here...
} else if (button.tag == 2) {
//TODO: Code here...
} else {
//TODO: Code here...
}
}
The tag property can be set via the InterfaceBuilder.
Hope this helps.
I think you can solve in 2 ways:
Create a property like:
#property (nonatomic, strong) IBOutlet UIButton *button1, *button2, *button3;
in your viewcontroller and link the buttons to them as referencing outlet on the XIB.
Give a different tag to each button on your xib and ask for the tag of the sender with UIButton *b=(UIButton*)sender; b.tag; like Markus posted in detail.
Solving my problem it all came down to transferring data between the mainView and subView.
In my mainView.h I declared an NSString and its #property
...
NSString *btnPressed;
}
#property(nonatomic, retain) NSString *btnPressed;
...
then in my mainView.m inside the switchView method I did this:
- (IBAction)switchView:(id)sender{
secondView *myViewController = [[secondView alloc] initWithNibName:#"secondView" bundle:nil];
btnPressed = [NSString stringWithFormat:#"%i", [sender tag]];
[myViewController setBtnPressed:self.btnPressed];
[self.view addSubview:myViewController.view];
}
This line in the code above actually takes care of transferring the data to the newly created subView:
[myViewController setBtnPressed:self.btnPressed];
Then in my secondView.h I declare exactly the same NSString *btnPressed and its #property (though this a completely different object than the one declared in main)
Then in my secondView.m I get the value of the button pressed I'm interested in.
- (void)viewDidLoad {
[super viewDidLoad];
int theValueOfTheButtonPressed = [self.btnPressed intValue];
}
This works well.
Don't forget to #synthesize btnPressed; as well as [btnPressed release]; in both mainView.m and secondView.m

UITableView headings shown on top of MBProgressHUD

So I have a subclass of UITableViewController that loads some data from the internet and uses MBProgressHUD during the loading process. I use the standard MBProgressHUD initialization.
HUD = [[MBProgressHUD alloc] initWithView:self.view];
[self.view addSubview:HUD];
HUD.delegate = self;
HUD.labelText = #"Loading";
[HUD show:YES];
This is the result:
.
Is there any way to resolve this issue, or should I just abandon MBProgressHUD?
Thanks!
My solution was pretty simple. Instead of using self's view, I used self's navigationController's view.
HUD = [[MBProgressHUD alloc] initWithView:self.navigationController.view];
[self.navigationController.view addSubview:HUD];
This should work for the OP because his picture shows he's using a UINavigationController. If you don't have a UINavigationController, you might add another view on top of your UITableView, and add the HUD to that. You'll have to write a little extra code to hide/show this extra view.
An unfortunate thing with this simple solution (not counting my idea adding another view mentioned above) means the user can't use the navigation controls while the HUD is showing. For my app, it's not a problem. But if you have a long running operation and the user might want to press Cancel, this will not be a good solution.
It's probably because self.view is a UITableView, which may dynamically add/remove subviews including the headers, which could end up on top of the HUD after you add it as a subview. You should either add the HUD directly to the window, or (for a little more work but perhaps a better result) you could implement a UIViewController subclass which has a plain view containing both the table view and the HUD view. That way you could put the HUD completely on top of the table view.
My solution was:
self.appDelegate = (kmAppDelegate *)[[UIApplication sharedApplication] delegate];
.
.
_progressHUD = [[MBProgressHUD alloc] initWithView:self.appDelegate.window];
.
[self.appDelegate.window addSubview:_progressHUD];
Works like a charm for all scenarios involving the UITableViewController. I hope this helps someone else. Happy Programming :)
Create a category on UITableView that will take your MBProgressHUD and bring it to the front, by doing so it will always appear "on top" and let the user use other controls in your app like a back button if the action is taking to long (for example)
#import "UITableView+MBProgressView.h"
#implementation UITableView (MBProgressView)
- (void)didAddSubview:(UIView *)subview{
for (UIView *view in self.subviews){
if([view isKindOfClass:[MBProgressHUD class]]){
[self bringSubviewToFront:view];
break;
}
}
}
#end
A simple fix would be to give the z-index of the HUD view a large value, ensuring it is placed in front of all the other subviews.
Check out this answer for information on how to edit a UIView's z-index: https://stackoverflow.com/a/4631895/1766720.
I've stepped into a similar problem a few minutes ago and was able to solve it after being pointed to the right direction in a different (and IMHO more elegant) way:
Add the following line at the beginning of your UITableViewController subclass implementation:
#synthesize tableView;
Add the following code to the beginning of your init method of your UITableViewController subclass, like initWithNibName:bundle: (the beginning of viewDidLoad might work as well, although I recommend an init method):
if (!tableView &&
[self.view isKindOfClass:[UITableView class]]) {
tableView = (UITableView *)self.view;
}
self.view = [[UIView alloc] initWithFrame:[UIScreen mainScreen].applicationFrame];
self.tableView.frame = self.view.bounds;
self.tableView.contentInset = UIEdgeInsetsMake(0.0, 0.0, 0.0, 0.0);
[self.view addSubview:self.tableView];
Then you don't need to change your code you posted in your question any more. What the above code does is basically seperating the self.tableView from self.view (which was a reference to the same object as self.tableView before, but now is a UIView containing the table view as one might expect).
I've Just solved that issue manually , it has been 2 years since Chris Ballinger asked but maybe someone get used of what is going on here.
In UITableViewController i execute an HTTP method in viewDidLoad , which is running in background so the table view is loaded while the progress is shown causing that miss.
i added a false flag which is changed to yes in viewDidLoad, And in viewDidAppear something like that can solve that problem.
-(void) viewDidAppear:(BOOL)animated{
if (flag) {
[self requestSomeData];
}
flag = YES;
[super viewDidAppear:animated];
}
I had the same problem and decided to solve this by changing my UITableViewController to a plain UIViewController that has a UITableView as a subview (similar to what jtbandes proposed as an alternative approach in his accepted answer). The advantage of this solution is that the UI of the navigation controller isn't blocked, i.e. users can simply leave the ViewController in case they don't want to waiting any longer for your timely operation to finish.
You need to do the following changes:
Header file:
#interface YourViewController : UIViewController <UITableViewDelegate, UITableViewDataSource>
- (id)initWithStyle:(UITableViewStyle)style;
#end
Implementation file:
#interface YourViewController ()
#property (nonatomic, retain) UITableView *tableView;
#property (nonatomic, retain) MBProgressHUD *hud;
#end
#implementation YourViewController
#pragma mark -
#pragma mark Initialization & Memory Management
- (id)initWithStyle:(UITableViewStyle)style;
{
self = [super init];
if (self) {
// create and configure the table view
_tableView = [[UITableView alloc] initWithFrame:CGRectNull style:style];
_tableView.delegate = self;
_tableView.dataSource = self;
}
return self;
}
- (void)dealloc
{
self.tableView = nil;
self.hud = nil;
[super dealloc];
}
#pragma mark -
#pragma mark View lifecycle
- (void)loadView {
CGRect frame = [self boundsFittingAvailableScreenSpace];
self.view = [[[UIView alloc] initWithFrame:frame] autorelease];
// add UI elements
self.tableView.frame = self.view.bounds;
[self.view addSubview:self.tableView];
}
- (void)viewWillDisappear:(BOOL)animated
{
// optionally
[self cancelWhateverYouWereWaitingFor];
[self.hud hide:animated];
}
The method -(CGRect)boundsFittingAvailableScreenSpace is part of my UIViewController+FittingBounds category. You can find its implementation here: https://gist.github.com/Tafkadasoh/5206130.
In .h
#import "AppDelegate.h"
#interface ViewController : UITableViewController
{
MBProgressHUD *progressHUD;
ASAppDelegate *appDelegate;
}
In .m
[UIApplication sharedApplication].networkActivityIndicatorVisible = YES;
appDelegate = (ASAppDelegate *) [UIApplication sharedApplication].delegate;
progressHUD = [MBProgressHUD showHUDAddedTo:appDelegate.window animated:YES];
progressHUD.labelText = #"Syncing To Sever";
[appDelegate.window addSubview:progressHUD];
This should work.
[MBProgressHUD showHUDAddedTo:self.navigationController.view animated:YES];
And to remove you can try
[MBProgressHUD hideHUDForView:self.navigationController.view animated:YES];

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