How to set a view to a tag set in code not in Interface Builder? - iphone

Question

I have an app that uses 4 different xibs, lets call them 1-4
So you start on view 1, if you press the button it takes you to view 2, on view 2, you have a back button (which takes you to 1) and forward button that takes you to 3 etc
Anyway, I am removing the next page buttons, and have added a swipe control instead of pressing a button, you can swipe to the next page.
However, I need to know how I can call a tagged view, using the swipe.
At the moment, the UIButton for next page is set in IB as tag 1
This is my swipe code (this is page 1 so only has a swipe left)
- (IBAction)swipeLeftDetected:(UIGestureRecognizer *)sender {
if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad){
Page2ViewController *UIViewController =
[[Page2ViewController alloc] initWithNibName:#"Page2ViewController~ipad" bundle:nil];
[self presentModalViewController:UIViewController animated:YES];
}else{
Page2ViewController *UIViewController =
[[Page2ViewController alloc] initWithNibName:#"Page2ViewController" bundle:nil];
[self presentModalViewController:UIViewController animated:YES];
Page2ViewController *VC = [[Page2ViewController alloc] initWithNibName:#"Page2ViewController" bundle:nil];
[self presentModalViewController:VC animated:YES];
[self.view removeGestureRecognizer:[self.view.gestureRecognizers lastObject]];
[VC release];
}
}
Whereabout in that code, can I tell it to swipe to tag 1?
Would appreciate any help :)
Thanks,
Chris
---- Updated FAO Rob;
In the appdelegate.m
- (void)swicthView:(int)viewControllerIndex :(CGRect)viewRect {
if (viewControllerIndex < 0 || viewControllerIndex > viewControllers.count) {
//invalid index passed to function - do nothing
}else{
if (subViewForceUseNibSize == NO) {
//pass the view frame size at runtime
if (CGRectIsEmpty(viewRect) || viewControllerIndex == 0) {
//no frame size so force full screen
if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad){
viewRect =CGRectMake(0, 0, 320, 480);
}else{
viewRect = CGRectMake(0, 0, 768, 1024);
}
}
}else{
//force use the nib size, so reduce size of NIB to leave display of NIB main nib below
viewRect = ((UIViewController *)[viewControllers objectAtIndex:viewControllerIndex]).view.frame;
}
}
//swicth our view
if (viewControllerIndex == 0) {
/*
for (UIView *subview in window.rootViewController.view.subviews) {
[window.rootViewController.view sendSubviewToBack:subview];
}
*/
for (int x = 1; x<[viewControllers count]; x++) {
if (((UIViewController *)[viewControllers objectAtIndex:x]).view.superview != nil) {
[window.rootViewController.view sendSubviewToBack:((UIViewController *)[viewControllers objectAtIndex:x]).view];
}
}
[window bringSubviewToFront:((UIViewController *)[viewControllers objectAtIndex:0]).view];
return;
}
if (((UIViewController *)[viewControllers objectAtIndex:viewControllerIndex]).view.superview != nil) {
((UIViewController *)[viewControllers objectAtIndex:viewControllerIndex]).view.frame = viewRect;
[window.rootViewController.view bringSubviewToFront:((UIViewController *)[viewControllers objectAtIndex:0]).view];
[window.rootViewController.view bringSubviewToFront:((UIViewController *)[viewControllers objectAtIndex:viewControllerIndex]).view];
}else{
((UIViewController *)[viewControllers objectAtIndex:viewControllerIndex]).view.frame = viewRect;
[window.rootViewController.view bringSubviewToFront:((UIViewController *)[viewControllers objectAtIndex:0]).view];
[window.rootViewController.view addSubview:((UIViewController *)[viewControllers objectAtIndex:viewControllerIndex]).view];
}
}

Answer 1

Looking at the revised code sample, it is clear that there is a UIAppDelegate method called swicthView [sic] that is used for transitioning between five different view controllers, all of which are loaded simultaneously. Given this structure, it is advised that you have a property to keep track of which of the five pages is loaded, and based on the left or right swipe, invoke swicthView to transition to that controller. Thus:
#interface ViewController ()
#property (nonatomic) NSInteger currentPage;
#end
#implementation ViewController
- (void)viewDidLoad
{
[super viewDidLoad];
self.currentPage = 0;
UISwipeGestureRecognizer *gesture = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleLeftSwipe:)];
gesture.direction = UISwipeGestureRecognizerDirectionLeft;
[self.view addGestureRecognizer:gesture];
[gesture release];
gesture = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleRightSwipe:)];
gesture.direction = UISwipeGestureRecognizerDirectionRight;
[self.view addGestureRecognizer:gesture];
[gesture release];
// the rest of the viewDidLoad
}
- (void)handleLeftSwipe:(UISwipeGestureRecognizer *)gesture {
if (self.currentPage < 4)
{
++self.currentPage;
[UIAppDelegate swicthView:self.currentPage :CGRectZero];
}
}
- (void)handleRightSwipe:(UISwipeGestureRecognizer *)gesture {
if (self.currentPage > 0)
{
--self.currentPage;
[UIAppDelegate swicthView:self.currentPage :CGRectZero];
}
}
Frankly, I'd strong advise retiring the swicthView design and rather employing a custom container view controller. If you watch WWDC 2011 - Implementing a UIViewController containment, you'll see a good introduction about the importance of keeping a view controller hierarchy synchronized with a view hierarchy, and see some practical demonstrations of custom containers.
The original answer, provided below, was based upon the original snippet of code that was performing presentViewController. It turns out that a very different solution was called for, outlined above, but I retain the original answer for historical purposes:
Original answer:
I assume you have the following sort of code in viewDidLoad:
UISwipeGestureRecognizer *gesture = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleLeftSwipe:)];
gesture.direction = UISwipeGestureRecognizerDirectionLeft;
[self.view addGestureRecognizer:gesture];
And then you gesture handler could be:
- (void)handleLeftSwipe:(UISwipeGestureRecognizer *)gesture
{
NSString *nibName;
if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad)
nibName = #"Page2ViewController~ipad";
else
nibName = #"Page2ViewController";
Page2ViewController *controller = [[Page2ViewController alloc] initWithNibName:nibName bundle:nil];
// if supporting iOS versions earlier than 5.0, then you should use:
//
// [self presentModalViewController:controller animated:YES];
//
// otherwise you should use presentViewController as done below.
[self presentViewController:controller animated:YES completion:nil];
[controller release];
}
Note, I'm don't remove the gesture (unless you really don't want the gesture there when you return back to this view, which is unlikely). Also note, I'm creating controller, presenting, and releasing.
I'm not understanding your repeated reference to tag properties in this context, as numeric tag values are used for identifying subviews of a view, not for identifying view controller or anything like that. So you say "UIButton for next page is set in IB as tag 1" and later you ask "Whereabout ... can I tell it to swipe to tag 1?" It doesn't make sense to "swipe to a button". You could, though, have the two handlers, the button's IBAction (which I'll call onPressNextButton ... I don't know what you called it) and the handleLeftSwipe call the same method, e.g.:
- (void)handleLeftSwipe:(UISwipeGestureRecognizer *)gesture
{
[self goToNextViewController];
}
- (IBAction)onPressNextButton:(id)sender
{
[self goToNextViewController];
}
- (void)goToNextViewController
{
NSString *nibName;
if (UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad)
nibName = #"Page2ViewController~ipad";
else
nibName = #"Page2ViewController";
Page2ViewController *controller = [[Page2ViewController alloc] initWithNibName:nibName bundle:nil];
[self presentViewController:controller animated:YES completion:nil];
[controller release];
}
References:
presentViewController, the preferred method for modal transitions.
presentModalViewController, the now deprecated method that you use if you need backward compatibility for iOS versions prior to 5.0.
Naming basics in the Coding Guidelines for Cocoa, for advice in naming variables and methods. Note variables generally start with lowercase letters and classes generally start with uppercase letters.