How is it possible to detect in NSCollectionView when the last item is visible on scrolling ?
I was looking for a similar solution as this but NSCollectionView doesnt have a similar layout methods.
Any hints ?
It is possible to get noted when the scroll view has scrolled by registering for boundsDidChange notification of the document view as described here Callbacks When an NSScrollView is Scrolled? .
That way one can check which part of the content of the collection view is displayed.
Related
I have a view with several subviews (NSButton, NSTextField, NSPopUpButton) and a NSImageView with a spinner icon which should be displayed on top of the other views while data is retrieved from the web.
To display the NSImageView on top I have set
imageViewSpinner.wantsLayer = true
imageViewSpinner.layer?.backgroundColor = NSColor.windowBackgroundColor.cgColor
The problem is, that the focus borders and PopUpButtons are still accessible/shining through the NSImageView (see attached video).
To solve this, I could iterate over all the other subviews and set them to "isHidden" or "disabled" but I wonder, if there is a cleaner solution to this problem, for example defining the NSImageView as topmost layer without things getting through?
You could put all of the other views inside of one container view and hide that.
You can also use a tab-less tab view to programmatically switch between view sub-hierarchies. (That basically achieves the same thing. It's better when there are more than 2 views to manage.)
I have an NSCollectionView in an NSScrollView.
The scroll view scrolls horizontally to move along the line of items.
Inside each each collection item is a vertically scrolling NSOutlineView.
I have NSButton objects for opening and closing collection items - as supplementary views in my collection.
I set up NSTrackingAreas on these buttons to support mouse over effects.
This works correctly, until I scroll, at which point the NSTrackingArea areas are clearly left behind (the mouse over effects happen when the mouse is where the button was, not where it is).
I rebuild my tracking areas in updateTrackingAreas in my button class, and this is called, but not often enough.
I have tried using .inVisibleRect when setting up my tracking areas, rather than explicitly rebuilding them, but that doesn't improve the tracking update.
I have tried calling updateTrackingAreas on the NSCollectionView when scroll occurs, but it is never passed down to the child views as I expected it would.
As a side note, I also have NSTextViews in my collection view items with toolTips that are very flakey too. They are often left hanging. Pointing hand cursors over links are often misaligned.
It feels as though the default updateTrackingArea is over-optimised and is not being called as often as it should.
So, I am about to embark on building my own tracking-area-tracker to register and update my views when they are not updated by default...
...but maybe someone can see something obvious that I am missing? Thank you.
The tracking area setup can be subtly broken when nesting scroll views incorrectly. See the answers regarding nesting scroll views here for details:
NSScrollView inside another NSScrollView
I want to make the search bar disappear by clicking the navigation bar item and make the collection view to fill the blank, animated obviously. ( like making the screen move upwards because the keyboard is showing )
is it Possible also to make it disappear when I scroll down an appear when I scroll up again ?
I dont think both ways will work at the same time but anyway I want to know how to make each way work.
thanks for the help :)
A collection view is a scroll view. A scroll view can have a delegate. A scroll view's delegate is told when the scroll view is scrolling. Therefore you can do anything you like in response to the user scrolling the scroll view, including moving the search bar.
I've got a Mac app involving an NSOutlineView. The view controller containing the outline view implements outlineViewSelectionIsChanging: to set selection state in a custom way on the cells in the outline view (it's view-based). But selectionIsChanging is called on mouse up, not mouse down. I've got other view controllers with other outline views in the app that get selectionIsChanging properly on mouse down, but I can't find a difference. Is this a property on NSOutlineView / NSTableView? Or is there another probable cause of this?
Turns out that if drag-and-drop is implemented on the outline view, it only posts selection messages on mouse up.
Can anyone please tell me how to fix the following issue.
I am building an iPhone app using Storyboard. I have a Navigation Controller as root view and off that a view controller. On this I have a few buttons that when clicked takes you to a table view controller. All fine and well, but when I link the buttons to their respective table views, the top navigation bar obscures the top cell in the table view controller.
Does anyone know why this is happening and how I can fix it?
Also it seems to have thrown off my layouts from the view controller from which they inherit.
See attached image for a better explanation perhaps.
I believe this is the intended behavior when using the translucent navigation bar. It's semi transparent specifically so that you can see items pass behind it (e.g. a table scrolling). If you don't want this, changing the navigation bar's style to opaque should solve the problem.
Since I wanted to keep the translucence, I just added a UIView between the navigation controller and the prototype cell (width of the view, height 60). That way the first cell in the table starts beneath the navigation bar but I can still see the scrolling underneath.
This is a bug/feature in IB when you use a translucent navigation bar, the content view runs under the navigation bar. For non transparent bars the content view begins after the bar. If your content view is a UIScrollView (UITableView is a descendent of UIScrollView) the content will be automatically scrolled so as to not be hidden under the navigation bar. So the problem only exist in IB when you run the app everything should be ok.
You just need go to the Navigation Controller properties, then Simulated Metrics, and change the Top Bar to be a Transluscent Navigation Bar WITH PROMPT. And that should be it. No need for that extra UIView