I have a class which subclassed UIView. The class only have touch methods (to rotate view according to users touch).
From storyboard i added a view to my ViewController's view and subclassed it with that custom class. The idea behind to receive its touch events, thats it.
In that View some UIButton is place covering the whole view.
Now requirement is when user clicks on button then its action should call else if he tries to rotate the view it should give spin rotation.
Every thing is working fine if i make user interaction of button to be false as obviously now Uiview is the responder. But this not what i want. I want button to be interact to action as usual and if user move his figure then rotate the view.
I achieve same thing with UIRotationGestureRecognizer but it is meant with 2 figures touch and i need to achieve same thing with single finger touch.
Any help and suggestions will be appreciated.
Related
I have my standard app setup, window with lots of views. From time to time I place an NSView over the top of everything, black with some transparency, to act an a dimmer/overlay.
I need this top overlay view to absorb all clicks so that any views underneath it can't be interacted with. E.g. an NSButton under this NSView won't be clickable.
How can I do this?
I have seen -(NSView *)hitTest:(NSPoint)aPoint but I don't want to put this on every single subview with a rule to block clicks while the overlay view is present.
Override the NSView with an empty mouseDown: and the views underneath will not receive any mouse events.
I'm trying to recreate the Facebook slideout menu trick (yes I know there's lots of libraries already).
When a user touches a button on the screen, a new view controller is switched in and a rendered bitmap of the previous screen is shown in the foreground of this new view. The uiimageview has a pan gesture recogniser attached to it to allow it to be moved around on the screen.
Currently it's requiring two touches to activate the gesture recogniser, once to bring in the new view controller, and once for the pan gesture to move the uiimageview.
My question is, on touch down can I bring in the new view controller and then pass the touch events to the uiimageview? Or is there any other trick that will help?
I haven't managed to achieve this exactly, but instead I've subclassed UIViewController so the root view controller never changes, just the content that's being displayed.
I have custom UIScrollView subclass with some content views inside. In some of them I have UITapGestureRecogniser. All works fine when scroll view is not scrolling. But when it scrolling content views does not receive tap action. What is the simplest solution to handle tap action by subview while scroll view is scrolling?
Details:
MyScrollView scrolls horizontally. It contains a lot of content views (e.g. MyContentView). Each MyContentView has width about one third of MyScrollView width. So there are about 3-4 visible MyContentView elements at a moment. The main behavior of MyScrollView is to 1)make sure that after scrolling one of MyContentView elements will be at center of screen and 2)to scroll to center of MyContentView if user taps on it. So the main answer I hope to get is how to "properly" implement handling of tap action in MyContentView while MyScrollView is decelerating.
I found some same questions and answers but none of them satisfied me. The best was to implement gestureRecognizer:shouldRecognizeSimultaneouslyWithGestureRecognizer: of UITapGestureRecogniser delegate. But in this case I sometimes (when I tap, make smaaaal drag and release finger so tap is steel recognizable(lets called it quasi tap)) have both tap and scroll events and it leads to bugs for me even if scroll view is not scrolling when I begin tap. When user make quasi tap my application tries to scroll to tapped MyContentView element and than immediately handle normal scrolling. It seems even more terrible, due to some other functionality start to perform after handling tap (it must not perform when normal scrolling).
I need solution where scroll view wait enough to decide it is not tap event and only then make scroll. Otherwise if tap event had recognized scroll must not happen.
You can go with the custom delegates methods as well, using #protocol. Implement those delegate methods in view controller where your UIScrollView has been added.
like in MyContentView:
In touchesBegan method,
[self.delegate contentViewTapped:self];
Now in ContainerView class where scroll view is added, implement that method:
- (void)contentViewTapped:(MyContentView *)myContentView {
NSLog (#"ContentView no: %d", myContentView.tag); // if tag has been set while adding this view to scrollview.
}
Go through the examples for #protocol.
Hope this is what you required.
Enjoy Coding :)
This is built into UIScrollView - take a look at the delaysContentTouches and canCancelContentTouches properties. This should alleviate the problem when dragging a small bit after a tap.
This is all system built-in behaviour. I would suggest sticking with what Apple has provided for the feel of your interface (how it reacts to small drags, for instance) so that your app doesn't feel out of place on a user's phone.
EDIT:
Alternatively, you could disable scrolling of your scroll view in you gesture recognizer and re-enable it once it's ended/cancelled.
Further Edit:
I don't understand - I've created a sample project that illustrates how to intercept touches in a subview of a scroll view using gesture recognizer delegate methods. Play close attention to the "Cancellable Content Touches" and "Delays Content Touches" properties of the scroll view. They're both YES for very important reasons.
You scroll view should be delaying content touches until it has determined if the user is attempting a tap, pseudo-tap (as you put it), or a pan for the scroll view. Apple has already written the functionality you're trying to build; UIScrollView will already do what you want.
The problem is that the system doesn't want a scroll view's subviews intercepting tap events while the scroll view is scrolling. To this end, it cancels touch events if it determines that the user is actually trying to pan. Setting "Delays Content Touches" enables this behaviour. Ensure it's turned on and you should be fine.
I would like to create a button in my UIView that when touched spawns another button under the finger which immediately starts to follow the finger.
I have seen a tutorial here that deals with button following finger, but i can not figure out how to make this button follow finger WITHOUT user tapping it after creation.
Using iOS 5.1 SDK with XCode 4.3.2
Any help?
You can add target/action pairs to a button for various control events: to make something immediately start following your finger, you probably want UIControlEventTouchDown.
Hook up your first button to call a method on your view controller for that control state. In that action method, create your new button, and shove it in a property on your view controller so that you can refer to it later. Also set a BOOL property on your view controller that's called something like shouldTrackButton.
To make the new button follow your finger, I guess the easiest way is a pan gesture recogniser on the superview. Set that up to call a method on your view controller. In that method, if the gesture recogniser's state is UIGestureRecognizerStateChanged, call translationInView: on the gesture recogniser, passing in the view controller's view (i.e. the superview of the buttons). Now, if and only if shouldTrackButton is YES, take the frame of the original button, translate it by that amount (using CGRectApplyAffineTransform and CGAffineTransformMakeTranslation), and set the new button's frame to the result.
Finally, in the same method, if the gesture recogniser's state is UIGestureRecognizerStateEnded, set shouldTrackButton to NO.
In my iPhone application I've set up a default, blank view called Main View into which various child subviews will be loaded for different parts of the application. It's the same approach as if I was using a tool bar to switch between subviews. That case, in the MainView controller I could hook IBActions to buttons in the toolbar, so that when a button was pressed, MainView added different subviews to itself.
In my situation, though, I need to tell MainView to change its subview from within the subviews. So here are two sister subviews, each with their own controller and xib, that would be loaded as subviews of MainView:
- StartView
- FormView
In StartView, after some animations and welcome stuff, a button triggers the camera image picker. Once the image picker returns the image, I need to tell MainView to remove StartView and add FormView.
It may be the result of a long day or my newness to iPhone OS but I'm stuck getting my head around the right way to set up my objects/controllers.
You never have more than one view controller active at a time. (The nav and tabbar controllers don't control views, they control other controllers.) In this case, you will have a single controller that has the MainView as its view property. It will add StartView and formView as subviews of MainView.
However, this is not a good design. It will overload the MainView controller by forcing it to juggle many views. It would be better to use a hidden navigation controller or a tabbar. Hierarchies of controllers can create the illusion from the users point of view for almost any interface layout you can imagine. There is no need to create a logical structure that mimics the visual one.
From your description you may only need a single view/view-controller pair: Set the formView controller to open the camera view before it displays the formView. When the camera is dismissed it reverts to the formView automatically. No fuss, no muss.