I am currently using this if statment to check if a uiview is loaded, this if statment works perfectly..
if (!myviewName.isViewLoaded) {
//not loaded so load my view
}
else (myviewName.isViewLoaded){
//is loaded so remove my view (unload)
}
However when I try to remove the view I dont think I am doing it correctly because I can never enter the first part of that if statement after the first time the view is loaded...
this is the code inside else (myviewName.isViewLoaded){
[myviewName removeFromParentViewController];
[animatedActionView removeFromSuperview];
the reason I use removeFromParentViewController is because I have added myviewName as a subview of animatedActionView, like so
[animatedActionView addSubview:b1VC.view];
[navigationController.view insertSubview:animatedActionView belowSubview:tabbarView];
the animatedActionView is being added as a subview to my navigationcontroller and I am placing it behind my tabbarview which is also a subview on my navigationcontroller..
hopefully this all makes sense..
Just to repeat my question, how do i remove a view so that it will access if (!myviewName.isViewLoaded) { properly.
anyhelp would be appreciated.
UPDATE:
As per reply I have been asked to explaine what I am trying to do in more detail which I will do here.
So, my original project has a NavController controlling all of the views I need for the first part of my project (querying the db) the second part of my project is displaying a ton or data.
So I am prototyping my final view in a new project to iron out all the problems I am likely to have, and also hopefully to do it in a way that will not get rejected by apple.
So when I reach the final view of my navController I am loading another navController inside of it. (will this get me rejected?)
this (sub)navController which I will refer to as otherNav will control the final view, it will load several different detailViewController with a special sliding transition animation which the user will be able to slide left and right between detailedViews.
I have also added a tabBar (in its own viewcontroller) as a subview to othernav, when the user transitions between detail views I plan to change the tabBar icons depending on the view, so when the user slide from one detail view to another then the previous icons will fade out and the new icons will fade in.
finally I have several other viewcontrollers which i call actionViews (this is what my question was about) which are loaded/inserted as subviews onto the otherNav but placed behind the tabBar and slide up and down when the tabbar button is selected and deselected.
here is a graphical representation of all of the views and how they sit on the screen.
You need to take care of myViewName's view:
[myViewName.view removeFromSuperview];
myViewName.view = nil;
Related
I am designing an iPhone application with a home page. This page has multiple buttons (6) that go to different things.
2 buttons are a simple view that just have some information and go back to the home screen. The next button opens up an email and I believe that will just be one view, so not a whole lot different than the other two.
Here is where it gets complicated. One button will take a picture, and another will select one from the library. Once that is done it will edit it and create an object that I will create. That object will be stored in an array, which will be opened by the last button one the home page and a UITableViewController will control that.
My first question is should I use a navigation based view controller or just a view controller that I can create myself? Or should I use something that I don't even know about?
Please Help!!! And if you help a sincere thank you!
EDIT:
Well i tried it my own way first and the only issue i'm having is this code
- (void) displayView:(int)intNewView {
NSLog(#"%i", intNewView);
[home.view removeFromSuperview];
Instructions *i = [[Instructions alloc]init];
instructions = i;
[self.view insertSubview:instructions.view atIndex:0];
}
It is in my SwitchClass, which controls the Main Window's view. I know it is working there because when it first runs the switch class directs it to the home screen. I know the method is being called because the console is displaying the NSLog thing, but it just won't switch.
Aside from the fact that you have 6 buttons, I would try and use a UITabBarController for what you are trying to do; it would seem more natural to me (but you should find a way to reduce you 6 button to 5, otherwise they will not be displayed all at once).
Otherwise, a UINavigationController seems fine to me. For each button you push a new controller to deal with that button functionality, then you pop back. It should work easily.
EDIT:
have you tried with?
[self.view addSubview:instructions.view];
Your first question Yes you should use navigation based controller ... so when you press any button will open the other view controller with animation.. also Navigation Based Controller keep track of the parent controller if you have any created objects will be retained in the parent view controller that is the root of the Navigation.
here is the steps that you should use.
1-Create Navigation controller in the main application delegate and make it's root is the view controller.
2-when you push the view controller that have 6 buttons .
3- you can check this link for get photo album also if you have changed the source type to camera then you can get the image...
Photo Libaray
4- once you get the image you can add it to NSMutableArray that exist on the NavigationViewController root in your case will be the view which have the 6 buttons.
5-sice every time you want to view the array which contain the photos you will initialize the data source of the uitableviewcontroller with the array that you save photos on.
Thanks
I think the problem is coming from one of two places:
As I understand it, these are all different View Controllers, correct? And they have their own xib files? If that is true, then calling:
Instructions *i = [[Instructions alloc]init];
is insufficient. You need to use
Instructions *i = [[Instructions alloc] initWithNibNamed:#"Instructions"];
in order to include that view that you have already constructed in the interface builder.
The other thing I see potentially going wrong is that you are inserting all the views at the same index. Think of the index as a layer in photoshop. If you want the new view to be visible overtop of the last one, then it needs to be a higher index. This is handled automatically if you use addSubview: instead of insertSubview: atIndex:
I have two subviews that load. One is a tabbar thats inside a viewcontroller which gets loaded fairly early on and the second is a view that appears when a tab bar item is pressed.
however when this subview is added it loads over the tabbar subview.. is there a way to bring to front or something along those lines?
There is a whole plethora of methods to choose from...see the section Managing the View Hierarchy in the UIView docs
I am putting an iPad application together that allows a user to work their way through a virtual tour. They are able to move forward through screens on which some will have buttons to other material such as a video or more info.
If Keynote supported Hyperlinks then it would be well suited but as it doesn't I am trying to recreate the tour within Xcode.
I am a newbie but have spent time researching and have code to display the 'slides' and the capability to move forward and back through them. The slides are no more that an image view with a full screen graphic and buttons for the various options, some slides are simple and have nothing other than back and forward but others will have additional links
However doing it in this simplistic way means I am ending up with a huge number of view controllers and XIB files, currently at 75 which I know must be more than any app should have. However it does work although on occasions when running it on the device and not in the simulator it will bomb out.
My questions are is there a limit to the number of view controllers in one app and will having a large number cause the instability? I'm aware of other ways to handle the views such as having them in arrays and pushing them out a single view controller but this won't give me the flexibility to tailor slides for different content.
I'd welcome any help or advice and I hope have gone about posting this question in the right way (its my first)
Many Thanks
Kieron
The code I am using to manipulate the view is
-(IBAction)goBack {
[self dismissModalViewControllerAnimated:NO];
}
-(IBAction)goForward {
Slide5ViewController *screen = [[Slide5ViewController alloc] initWithNibName:nil bundle:nil];
screen.modalTransitionStyle = UIModalTransitionStyleCrossDissolve;
[self presentModalViewController:screen animated:YES];
[screen release];
}
Kieron,
Why not have one "slide" view controller and a different image only? Use some sort of data structure to keep information about the buttons, images, and pathways for each slide, and then just keep re-using the same view controller for each slide?
The view controller can then dynamically load each image as it transitions between the currently visible view and the next instantiation of itself... It should be possible using only 1 view controller.
If you're comfortable with using Interface Builder, keep using the XIB files to lay everything out. However, instead of setting each "File's Owner" to a different view controller, set them all to the same one. Then, inside your IBAction methods (when the user pressed a button), use some logic to say "I am on this view right now, and the user pressed this button, so which one should I go to next?"
Then, call a method like loadNewSlide: that might look like this:
- (void) loadNewSlide:(NSInteger)slideNumber
{
// Make a string with the new XIB name
NSString* xibName = [NSString stringWithFormat:#"slide-%d",slideNumber];
// Create the next slide view controller (it doesn't matter if you create a slide view
// controller from within another slide view controller, remember, they are all just
// objects)
SlideViewController *newSlideViewController = [[SlideViewController alloc] initWithNibName:xibName bundle:nil];
// Change the view
UIWindow *theWindow = [self.view superview];
[self.view removeFromSuperview];
[theWindow addSubview:newSlideViewController.view];
// Release, the view stack now should be retaining the view controller instead
[newSlideViewController release];
}
This will work MUCH better than running "modally" with 75 view controllers (as you had previously suggested) because this will only keep 1 slide in memory at a time - whatever you are currently looking at - and then will load the next slide just in time to move to it.
Fist of all, what error is in the log?
Did you properly implemented viewDidUnload method of view controllers? View controllers should be able to unload loaded xib. Also, release data in didReceiveMemoryWarning.
Second, it could be better to use UINavigationController to handle view controllers stack instead of modal view controllers stack. You can hide navigation bar or customize it.
I have application with multiple UIViewControllers using navigation controller. UIViewController contains tableView, searchbar (that I can show/hide) and toolbar. All of this is added as subviews to its view. All this subviews are created after UIViewController is initialized and their content depend on UIVievController's content.
It works fine expect one problem. When I play with my app a little, move back and forth, open some modal views etc sometimes after navigating back to my root VC all it's subviews dissapear and all I get is white screen.
I double checked all my code and I can't find source of problem (I certainly don't remove them myself). I wasn't able to find exact patern how to reproduce this, it seems random. Any idea why iphone would remove my subviews from VC? I would post some code, but I don't want to put it all here and I am not sure which part is important, so if you wish to see some, let me know
Add your views in loadView or viewDidLoad: when viewDidUnload is called, the view is released, so they need to be created again when the view is shown again.
I posted earlier but am running into similar problems again. Basically the way that my app is setup there is a top bar that is basically just a static image that has UIButtons placed on top of it. That is the Main View Controller and is persistent no matter what view is shown beneath it. I can't use a navigation controller because it is not possible to change the height and I need the bar to be significantly larger than a navbar. However my bar is functioning in much the same way. There is a "Home" Button, a "Back" Button and several destination buttons.
I understand how to switch views from say the home screen. My confusion comes with the back button. In order to press back the app is going to need to know what view is currently being displayed so that it can be removed from view and a new subview can be added. Ideally I would use the UINavigationController so that I can push and pop views which is really what I want to do here, however that is not possible because of the visual problem.
Does anybody know of a method that returns the current displayed view so I could do something like the following
[currentview.view removeFromSuperView];
[self.view insertSubview:experienceViewController.view atIndex:0]
You can use UINavigationController with the nav bar hidden. Put the nav controller inside a view that does have your jumbo toolbar and you'll have access to the push/pop behavior you're looking for.