Views within custom UICollectionViewCell not receiving touch events - events

I have a UICollectionView which supports horizontal and vertical scrolling. Each collection view cell is a subclass of UICollectionViewCell and they are loaded from a NIB that contains UIButton's, UITableView's and even another UICollectionView. They are all inside a TPKeyboardAvoidingScrollView.
Scrolling works perfectly both horizontally and vertically, but it is not receiving touch events on the elements on the individual UICollectionViewCell. When I touch any of the elements, say a button that's part of the UICollectionViewCell, then all that I get is the didSelectItemAtIndexPath event on the UICollectionViewDelegate - I am unable to get any touch event passed through to one of the subviews of the collection view cell the tap occurs on.

After going through some other stackoverflow articles I eventually found what caused my problem - the XIB file I used to initialise the UICollectionViewCell had a normal UIView element at the root; even though it was marked as a subclass of a UICollectionViewCell and behaved fine in any other way, that prevented the events to flow through.
So - if your custom UICollectionViewCell XIB file looks something like this at the the root (see the icon next to the Data Entry Matrix View, which is the name for my UICollectionViewCell subclass), then you will have the same problem:
My solution was to add a proper UICollectionViewCell class to the XIB, then move all the subviews under the existing Data Entry Matrix View into it, delete the old root, then reconnecting the Outlets. The end result looks like this:
You can see the different icon used - that's what you want. Once I'd change my XIB like this the events were passed through.
In the raw XIB file (view as Source), the non-working version introduced the root element as
<view ...>
whereas the working version changed that root element to
<collectionViewCell ...>
Hope this saves someone else a couple of hours...

a have the same problem for UIButton in my custom UICollectionViewCell
Adding that function to my UICollectionViewCell solved problem for me:
- (void)setBounds:(CGRect)bounds {
[super setBounds:bounds];
self.contentView.frame = bounds;
}

If you have a view/scrollView at the root and it is attached to backgroundView or selectedBackGroundView remove it and it will work fine.

Related

Xcode add collection view cell to collection view on interface builder

I am relatively new to using XCode interface builder.
When trying to drag a collection view cell onto an empty collection view, the interface builder refuses to do so.
Please have a look at attached screenshot:
Am I doing anything wrong?
Note that I can do the same on a storyboard but not on a normal xib file.
You can only add a UICollectionViewCell inside a UICollectionView when working on a Storyboard file. For sure, you must be using a single nib file and that's why it isn't working.
If you wanna use a custom UICollectionViewCell, then you must create a subclass of UICollectionViewCell. When subclassing UICollectionViewCell don't forget to check the box that says "Also create XIB file" beneath the expandable menu of "Subclass of". Now, try to drag a UICollecionViewCell onto the canvas and custom it the way you want.
Another posibility would be using a Storyboard file. Try setting your UICollectionView inside a scene in the storyboard and then drag a UICollectionViewCell inside it. When dragged, create a UICollectionViewCell subclass and assign it to the UICollectionViewCell you dragged previously inside your CollectionView in the Identity inspector.
In either case, don't forget to set the reuse identifier of your UICollectionViewCell in the Attributes inspector :)
Here is a code sample from Apple of how to create a UICollectionView with a custom UICollectionViewCell using a storyboard.
https://developer.apple.com/library/ios/samplecode/CollectionView-Simple/Introduction/Intro.html#//apple_ref/doc/uid/DTS40012860
Hope this helps :-)

NSToolbar in Xcode 7 using Storyboards (NSWindowController -> NSSplitViewController)

Hi I've seen this question asked a few times already but with no definite answer yet so I created it for xcode 7 and swift2 (which may have changed things a bit anyway).
I created a project using Xcode 7 and Cocoa OSX Story boards + swift2, so my project started with a NSWindowController that Connects to a NSViewController (as expected!). I added a NSToolbar to my window controller and added a NSButton to the toolbar. I changed my NSViewController to be one of the new NSSplitViewController that links to three NSViewControllers and displays their views horizontally - with vertical dividers - (similar to the layout you see in the photo app or pages in Yosemite +). My final goal will be that the button in My toolbar shows and hides the first split.
It is my understanding is, and I would expect that to achieve this I should create an action in the NSSplitViewController that changes the auto layout constrains more or less in the way they are working it out here: How to do collapse and expand view in mac application?.
And then somehow link this action to the NSButton that is in the Toolbar... which happens to be in the NSWindowController (far up and isolated in the hierarchy)...
I have already gone through other questions about NSToolbar and storyboards and failed to accomplish my goal:
The YouTube video: Cocoa Programming L17 - NSToolbar which is the closest I found to solve the problem, but his method does not work for storyboards, only creating your own xib file.
In this question: How to use NSToolBar in Xcode 6 and Storyboard? One person proposes to make the link using the first reponder and expecting everything to hook up at run-time (which looks a bit dodgy and not the way apple would implement it I think...). A second person suggested to create a view controller variable in the NSWindowController and manipulate its properties from there... but again, a bit dodgy too.
One latest comment I saw in that question which seems the best way to tackle the problem (but still not as good as I guess it could be) is to add a NSObjectController to the dock of each scene and when the scene loads, set the values of the objects to the other secene's controller. Is this really the best way to go ahead? If so, how could I achieve this one?
Apple did mention (again) in WWDC15 that they created storyboards for osx and the split-view controller that owns view-controllers so that you can move your logic and work to the specific view-controller, so I would be expecting to do everything from inside my split-view controller as this is the target that needs to change.
Does anyone know how to achieve this from the view controller itself? I really haven't been able to find a way to connect my ToolBarItem to it.
OK, I've created this question quite a few days ago and no answer so far so I've answer with what I recently did to overcome the problem.
After I created my Xcode project I did this:
Created a subclass MySplitViewController for the NSSplitViewController
Added an IBOutlet for each NSSplitViewItem. For example:
#IBOutlet weak var mySplitViewItem: NSSplitViewItem!
Created a subclass WindowController for the NSWindowController
Added an IBAction in the WindowController class that links to the NSToolbarItem (my button)
Added a property that gets the Window Controller's content as MySplitViewController
var mySplitViewController: MySplitViewController {
return self.window?.contentViewController as! MySplitViewController
}
Now I can access the split view controller's property from the Window Controller in the action I created:
mySplitViewController. mySplitViewItem.collapsed = true
I created some sample code that does this (but using a view controller and changing the text for a label here, just in case someone wants to see a working project with this behaviour. And a blog post about it too :)
One person proposes to make the link using the first reponder and expecting everything to hook up at run-time (which looks a bit dodgy and not the way apple would implement it I think...).
I think this first responder method is actually the proper way.
As an example:
Add something similar to the following, in whichever view controller makes sense.
#IBAction func doSomething(_ sender: AnyObject?) {
print("Do something.")
}
This will magically show up in the first responder:
In your storyboard, right-click the orange "first responder" icon above your window controller, and you should see doSomething in the very long list. You just need to connect that up to your toolbar button.
In the following screen capture, you can see my "Toggle Sidebar" button is connected to the toggleSidebar action in my first responder.
I didn't even have to write this method — it's provided by NSSplitViewController:
#IBAction open func toggleSidebar(_ sender: Any?)
So, I was working this same issue and finding no solution as you experienced. I read your post and was trying to figure how I would implement your solution when it occurred to me to use a notification. In about 30 seconds, I had a perfectly fine working solution:
In your windowController add an IBAction to post a notification like so
-(IBAction)toggleMasterViewClicked:(id)sender
{
[[NSNotificationCenter defaultCenter] postNotificationName:#"TestNotification" object:nil];
}
Hook up that action to your NSToolbarItem, then in the viewController add self as an observer for that notification like so
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(toggleMasterView:) name:#"TestNotification" object:nil];
In your case, selector would be updateMyLabelText
I don't really see any downside here. No reference to other objects needed, no dependancies. Works flawlessly for me
While connectiong IBActions works by using either the First Responder or by adding an "Object" to the scene, then changing its class to the window's view controller class, this doesn't help with IBOutlets and delegates that you'd like to point to the view controller.
Here's a work-around for that:
Add the Toolbar to the View Controller, not to its Window. That way, you can make all the IBOutlet connections in the View Controller Scene easily. I've done that for years and found no issues with it, even when using Tabs.
You'll have to assign the window's toolbar in code, then. E.g. like this:
#interface ViewController ()
#property (weak) IBOutlet NSToolbar *toolbar; // connect this in your storyboard to the Toolbar that you moved to the View Controller Scene
#end
- (void)viewWillAppear {
[super viewWillAppear];
self.view.window.toolbar = self.toolbar;
}

NSView added as subview doesn't show

I have a puzzling problem. Working on a cocoa app in mac os x 10.7.
My app main window contains a split view. In a certain use context in one of the subviews of the split view is loaded a custom view with some labels (nstextfield) and a split view (instantiating a view controller that loads a nib and getting view from that controller). Frame of the custom view is set to split view subview bounds and everything works fine.
Problem is that one of the subviews of the second split view should be loaded (same method: view controller-nib-view-frame/bounds) with a custom view containing a table view and a button, but in this case nothing shows. Everything is done the same way but last custom view is not visible. Any idea?
Thanks
(edit)
this is the code I use to instantiate controller for the view to be added, get the view, and add it as subview to a subview of the split view
- (void)loadSubview {
self.subviewToAddController = [[viewController alloc] initWithNibName:nil bundle:nil];
//nib name is coded in the controller class definition
[[self.subviewToAddController view] setFrame:[self.splitViewContainerSubView bounds]];
//container subView is an outlet
[self.splitViewContainerSubView addSubview:[self.subviewToAddController view]];
}
However I don't think the problem is in this code because if I ask the container subview for its own subviews I can see the new subview is present in the list. It just doesn't show. If I add it as a subview of the split view (a test a just made) or as subview of the subview of the most external split view it is correctly showed too (sorry for the confused explanation, I would need a diagram but in this moment I can't make it)
To elaborate more my doubt (I didn't want to misled so I didn't mention before) can't it be a problem of coordinates, so view is correctly loaded and added as subview but is not visible because hidden by something or showed out of visible area?
(update)
Sorry it took so long to post an update.
After more testing I found out the problem is related to autolayout. No idea what the exact problem is and how to solve it. I ended up turning it off for the nibs the were in troubles and use the old way to set interface objects position and size/resize. Not the best way but for now I can go on.
My best guess is that you didn't set the autoresizing masks of the view properly.

Cocoa: NSView drawRect painting over IBOutlets

I have an NSView in IB which sits above the app window. I have a subclass of NSView (AddSource) which I assign to the NSView.
On awakeFromNib I instantiate the view:
//add a new Add Source class
addSourceView = [[AddSource alloc] initWithFrame:NSMakeRect(0.0, 959.0, 307.0, 118.0)];
[[winMain contentView] addSubview:addSourceView];
in addSourceView's drawRect method I am adding a white background to the view:
[[NSColor whiteColor] set];
NSRectFill(rect);
[self setNeedsDisplay:YES];//added this to see if it might solve the problem
In winMain's contentView I have a NSButton that when clicked slides the addSourceView onto the window:
NSRect addSourceViewFrame = [addSourceView frame];
addSourceViewFrame.origin.y = 841.0;
[[addSourceView animator] setFrame:addSourceViewFrame];
But it seems as if the app is painting over the IBOutlets I placed on the NSView in IB. If, in IB, I repoistion the NSView so that it is on screen when the app launches everything works fine, the IBOutlets are there as well as the background color.
I'm not sure why this is happening. I've done this before with no problems. I must be doing something different this time.
Thanks for any help.
*note - on the 3rd screen capture, when I say this is what the app looks like when opened, that's when I hard code the Y position of the NSView. When it is functioning correctly it should open as screen capture 1.
Most likely your buttons and custom view are siblings, i.e. they are both subviews of your window's content view. Since siblings are "Stacked" depending on the order in which they are added, when you add the view in code it is being added on top of the buttons. You should be able to fix it by explicitly specifying where the view should be positioned relative to its new siblings like so:
[[winMain contentView] addSubview:addSourceView positioned:NSWindowBelow relativeTo:nil];
which should place it below any existing subviews of your window's content view. Also, remove the setNeedsDisplay: line in drawRect, that leads to unncessary, possibly infinite, redrawing.
EDIT: OK I see what you're doing.
I would suggest creating a standalove view in the NIB by dragging a "Custom View" object into the left hand side (the vertically-aligned archived objects section) and adding your controls there, that should ensure the controls are actualy subviews of the view, then you can just create a reference to the archived view in code, and add/remove it dynamically as needed.
Honestly though, you should probably be using a sheet for these kinds of modal dialogs. Why reinvent the wheel, and make your app uglier in the process?
You added TWO AddSource views to the window. You added one in IB - this view contains your textFields and buttons that are connected to the IBOutlets and it is positioned outside the window.
Then in -awakeFromNib you create another, blank AddSource view (containing nothing) and animate it into the window.
I can't recommend highly enough the Hillegass as the best introduction to IB and the correct way to build Cocoa Apps.
Also, Assertions can be useful to make sure what you think is happening is actually what is happening.
If you are certain you added a button to your view in IB, assert it is so:-
- (void)awakeFromNib {
NSAssert( myButton, #"did i hook up the outlet?");
}
NSAssert is a macro that has zero overhead in a release build.
Calling [self setNeedsDisplay:YES] from -drawRect just causes the same -drawRect to be called again. This will give you big problems.

How to pass scroll events to parent NSScrollView

I need fixed-size NSTextViews inside a larger scrolling window. IB requires that the textviews be inside their own NSScrollViews, even though their min/max sizes are fixed so that they won’t actually scroll. When trackpad gestures are made within the textview frames (regardless of whether they have focus), they are captured by the textviews’ scrollviews, so nothing happens.
How do I tell the textviews’ scrollviews to pass scroll events up to the window’s main scrollview? (Or perhaps I should be asking how I tell the window’s main scrollview to handle these events itself and not pass them on to its child scrollviews.)
The IB structure is like this:
window
window’s content view
big scrollview for window (desired target for scroll events)
box
swappable content view in separate xib
scrollview for textview
textview
And, yes, the window does scroll correctly when the textviews do not have focus.
You needn't create a outlet "svActive" to track your super scrollview. Just write this sentence in scrollWheel event:
[[self nextResponder] scrollWheel:event];
this will pass the event to next responder in the responder chain.
IB does not require you have a text view inside a NSScrollView; this is just the default, because most of the time you'll want your view to scroll. Select the NSTextView and choose Layout > Unembed Objects. Note that after this point, you can no longer move or resize your view in IB. This seems to be a bug.
Here's an example of how to put two NSTextViews in a single NSScrollView.
Add two text views next to each other; put some text in them so you can see what's happening.
Select the views; choose Layout > Embed Objects In > Scroll View. This puts them in a generic NSView inside a NSScrollView.
Select the text views; choose Layout > Unembed Objects.
Turn off the springs and struts (autosizing) for each text view, so they don't resize when you shrink the scroll view.
Take note of the height of the document view (here it's 175).
Make the scroll view smaller. This also resizes the document view (NSView).
Restore the document view to its original size (I set the height back to 175).
Done! Scrolling works as you'd expect.
This is really embarrassing. After weeks of putting it off, I made a first attempt to get a subclassed NSScrollView to behave passively — and it turned out to be a no brainer.
Here’s the subclass:
h file:
#import <Cocoa/Cocoa.h>
#interface ScrollViewPassive : NSScrollView {
// This property is assigned a ref to windowController’s main scrollview.
NSScrollView *svActive;
}
#property (nonatomic, retain) NSScrollView *svActive;
#end
m file:
#import "ScrollViewPassive.h"
#implementation ScrollViewPassive
#synthesize svActive;
// Pass any gesture scrolling up to the main, active scrollview.
- (void)scrollWheel:(NSEvent *)event {
[svActive scrollWheel:event];
}
#end
There’s no need to make outlets for these passive scrollviews; I give them their refs to the main scrollview right after their xibs are assigned as content to the NSBox:
[self.boxDisplayingTextViews setContentView:self.subviewCtllr1.view];
// A textview's superview's superview is its scrollview:
((ScrollViewPassive *)[[self.subviewCtllr1.textview1 superview] superview]).svActive = self.scrollviewMain;
That’s it. Works like a charm.
I find that IB3 and Xcode4 both fight you if you try to do this directly, but you can do it indirectly. First, drag the textview out of the scrollview and delete the scrollview. You'll wind up with an orphaned textview. I don't know any way to get IB to allow you to put this into your window, but it'll be in your NIB. Now, attach an IBOutlet to it, and at runtime do a addSubview: and adjust its frame to move it into whatever scrollview you wanted it to be in.
In my experience, NIBs are a good thing, but every complex NIB I've ever worked with needed some final rearranging in code.
Based on #phaibin's answer, here's how you'd do it in Swift 4.2.
First, subclass NSScrollView and override scrollWheel:
class ScrollThingy: NSScrollView{
override func scrollWheel(with event: NSEvent) {
self.nextResponder?.scrollWheel(with: event)
}
}
Then place the ScrollThingy class (or whatever you name it) on the NSScrollView that is wrapped around your NSTextView. The parent NSScrollView will get the scroll event thereafter.

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