I've got a UIView which the user drags on and off of the screen (like a drawer).
The UIView has a bunch of buttons, some always visible, others hidden until the user 'opens' the drawer.
For some reason, the UIButtons that are 'off screen' on the initial UIView presentation aren't being passed events when they're later moved onto screen.
While the others receive all the events all the time.
Seems buggy to me, I would have thought the SDK would handle all this itself?
I've got a very simple example which you can take a look at: http://cl.ly/2r1c0k2p361B3B1A461L
Thanks in advance.
After a bit more research, it had to do with the views clipping boundaries.
The buttons were being drawn, but were essentially out of the views frame, so no events were registered.
More details on this question: Programmatically Created UIButtons Below Screen Not Working?
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My goal is to create an alert that has three text fields, one taller than the others, and an image that, when tapped, allows the user to choose a picture to replace a set default one.
After unsuccessfully searching for a library for this, I decided to create my own alert by placing a UIView off the screen and, when prompted by a button, would zoom onto the screen; it consists of all the elements I require.
When I run the application, the view pops up correctly, but none of the elements on the view are responding to touch. I've checked that isUserInteractionEnabled for everything is turned on.
What's also odd is that when I keep the view on the screen (instead of placing it some distance away on Storyboard), all the elements work fine.
I'm assuming it had something to do with the animation. I tested it with a fade in instead of a displacement, and the result was the same - the elements were unresponsive.
In order for your elements to be responsive you have to link the action of you clicking them to your view's code. You can do this in a non-programmatic manner by ctrl-clicking your element on story-views and then dragging to the view controller. Then choose action instead of outlet, and choose when the action you want will be triggered (bottom part). Then insert your code in the viewController.
So I figured it out. I used the debug view hierarchy and saw that the alert was behind the elements behind it, even though it was still being shown (for some reason). I changed the zIndex of the UIView and it worked!
I have been only using Xcode 5 for a little while now and I need help when it comes to auto scrolling a UIScrollView. I am using a single view application. I need the screen to scroll down at a pace that speeds up incrementally. Also I need the screen to keep progressing even when the screen is touched. If someone can explain which code goes where it would be great! Your help will be greatly appreciated. :)
Check out this library: https://github.com/danielamitay/DAAutoScroll
It stops to scroll when the user touches the screen and that's the only solution I see possible. I don't even see why you wouldn't want the user to be able to stop the scrolling..
OK, just adding this from your duplicate question.
I suspect the Piano Tiles game is actually using something like Sprite Kit.
This allows a lot more control over thing like "scrolling" speed.
Instead of using a UIScrollView you would use an SKNode as a layer with the buttons added to that parent layer.
Then using the update game loop you can incrementally increase the speed of the movement based on the time since the game started.
In essence... don't use UIScrollView, don't use UIKit, use SpriteKit.
I can see a few options:
1) suggested by Fogmeister, use Sprite Kit instead.
2) see setContentOffset
3) just use a normal view as parent, then have another child view on top with the full content (would be longer than the parent view), create a NSTimer to periodically call a method which scrolls the child view in whatever direction and speed as required.
Note that might need something on top to mask around the child view from showing the suppose-to-be-hidden sections of the child view.
Hope this helps
I know this has been probably asked before but I've seen many approaches and i don't know which is best for me, so plz don't send me a link to another post unless it addresses my problem directly.
I have a controller which has a uiview on the top (like a header) (this header is bigger than it seems because is partially hidden on top). on that view i have a uibutton which now with a touch up inside shows the entire header view and taping again returns it to its starting position (changing frame with animation). I want to also be able to drag the view but only changing position on the y axis(dragging up and down)... i was thinking of adding the dragInside/Outside event to the button but this doesn't give me the position of the finger... and also want to know when the user releases the drag so the view ends animation to any of its two possible states (showing or partially hidden). Is this a "touches began" , "touches moved" , "touches ended" thing? if it is please provide a code example. I also want to do this with another view but this is on the left side... same thing but this one moves on the X axis... any help is appreciated. or maybe it can be made with drag event if i only can save a CGpoint of last touch, maybe that's better, any other suggestions
Look at using a UIPanGestureRecognizer to detect the touch movements. Use the translationInView: of the gesture to set the view y position. The translation is the total movement since the start of the gesture so you don't need to remember and accumulate the offset position yourself.
The main thing to worry about while implementing this is bounding the y position of the view so that no matter how far the user drags the view won't go too high or low on the screen.
Use a UIPanGestureRecognizer, that's a class dedicated to handling such drag/pan gestures.
Everything is described here in Apple's documentation, including examples, so you should find your answer here.
There is also some sample code in Apple Developer Library that shows you how to use Gesture Recognizers if needed.
I've been banging my head with this issue for the last two days. Googled a lot but wasn't able to find the answer yet, so I decided to request some help here. Let's see if I get any luck.
I'm coding a reusable control that consists of an UIView with a variable number of customized UIButtons. I implemented initWithFrame:, initWithCoder: and drawRect: where the buttons (which are built prior to drawing) are actually added to the view. Everything is done programmatically since the UIButton content should be supplied when using the control, so there's no XIB for this UIView.
This UIView, let's call it CustomizableBarButton is then used in an UIViewController, let's call it MyTestViewController with a view on it, let's call it customizableBarButtonView.
MyTestViewController's GUI was set on IB where an UIView was tied to customizableBarButtonView (the class was matching accordingly).
MyTestViewController's is a pretty standard class except for the viewWillAppear: that initializes the buttons and passes them to the CustomizableBarButton along with some other options.
The issue is that everything works perfectly...except for the first time!
I mean, when I run the app on the simulator (I haven't tried it on the iPhone yet but I strongly believe that it's not an hardware issue) the MyTestViewController shows the customizableBarButtonView background but not the buttons. Now when you click on the place where a button should be all the buttons suddenly appear!
I'm puzzled since the CustomizablebarButton drawRect: runs before the strange "click n'appear" effect and the buttons are actually added to the subview.
Another hint that my help: if you don't click on the buttons (so you still got no buttons yet) but rotate the device they will also appear as if by magic!
It is probably something very simple but I'm missing it and I'm going nuts...
Can someone lend a hand on this, please?
Thanks in advance!
You said you're adding the buttons in drawRect:. Don't do that. You need to add the buttons in your init methods.
I have a ScrollView with several UIButtons (custom type). The UIButtons are shown as Images. I made it to subclass UIButton to shoot an event if the user taps on a button for a long time (approx. 3 seconds).
If a user tap's one of the subclassed UIButtons i thought about animating the selected UIButton the way the apps are animated if you want to delete them.
I have nearly no experiance with animations. Is there something somebody can point me to? All i've found was transitions, but thats not what i need.
(Ill rephrase) On SO, there are quite a few questions to answer this. One of then is this link How do you make images wobble like on the iPhone home screen?