The default behavior in a Xamarin Tableview is to highlight the cell someone selects on touch up inside. The Tasky example app shows this behavior.
The standard iOS behavior is to highlight the cell on touch down inside, then allow the user to scroll (un-highlights cell). Then the cell is selected when you touch up inside. Mail is a good example of this.
We're racking our brains on this one. This behavior seems like it should be built in. We tried to build it ourselves with gestures but it gets a bit tricky.
This seems like a common problem that has already been solved, so we don't want to re-invent the wheel. Rdio even does it the 'right' way :).
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I'm an intermediate iOS developer who's trying to jump on the OSX side of things.
I've been struggling to create an accordion-like display of several views, where only one view at a time can be unfolded to occupy the whole parent's view's available space. In other words, click on a view's title bar, it will both open/unfold this view and close/fold the currently open view, with animations'n'all. Oh end, I need the views' contents to be scrollable.
I tried starting from Apple's NSStackView sample code, but first it is not quite what I want, and what's more, I can't figure out how to start from here to end up where I eventually want to be.
Then I tried to master the Auto-Layout facilities but with no success. Truth be told, this whole Auto-Layout thing still confuses me some.
Does any of you have clues as to how I should proceed? Sample code? Tutorials (I tried several Auto-Layout tutorial but at the end of the day they still leave me missing the tricks I'd need to figure...).
Thanks.
/Julian
Check out the sample code: InfoBarStackView. It creates an accordion-like interface, the one difference from what you're describing is it lets multiple views be revealed at the same time (although, that's a simple difference).
It uses NSStackView and autolayout constraints to create the interface and drive the reveal/hide animations.
The stack view could also be put into an NSScrollView to allow the content to be scrollable. (Something similar was done during a WWDC 2013 Cocoa Animation talk).
When editing code, Xcode is capabale of displaying in-text controls, like drop down buttons which can show context menu's. I've seen other OS X apps that handle text capable of similar features. See the attached sample.
I presume this effect is obtained using NSTextAttachmentCell - although I'm not sure whether this is the proper way to implement this.
For my own app I would like to use this technique as well.
I have the following questions:
Is NSTextAttachmentCell the correct way to implement such a feature? If not, what would be?
How do I attach a control -comparable to the one in the above sample- to a specific range of text so that its location within NSTextView is dynamic and follows layout actions?
I found this which gives some hints but does not cover the attachment to specific text ranges.
Although NSTextAttachmentCell will work, it has a disadvantage: the cell will become just a glyph in the text which was not what I wanted. It distorts the layout of the text, is selectable etc. I wanted the cell to be drawn over the text, just like the behaviour in Xcode.
The challenge was to find a way of translating a point from a Mouse Moved event to the position of a particular string of characters inside the NSTextView.
After some more digging I found a little gem in Apple's demo apps called LayoutManagerDemo. This demo shows a custom subclass of NSTextView capable of highlighting individual characters, words and lines while the mouse is hoovering its view. From there on it was pretty easy to fade in a button at the required NSPoint and then show a popup menu with some options.
Although I know of a solution to this problem, I am interested if someone can explain this solution to me. I also wanted to get this out there because I could not find any mention of this problem online, and it took me several hours over several days to track down. I have an NSTableView behaving strangely regarding redraws and its selection. The problem looks like this:
Table contents fades in, instead of appearing instantly upon it's appearance on screen. When scrolling through the contents, the newly appearing rows also fade in. When you make a selection (single or multiple), and scroll it off screen, then make another selection (that should replace, not add-to first selection), the first selection does not get cleared properly. If you scroll back to it, it is still there, in addition to your new selection. This is a display-update problem, not selection problem - i.e. your new selection is valid, it is just displayed wrong.
I tracked this through the NSArrayController I was binding to, the underlying Array, sorting, all the connections, and settings, etc., but all that has nothing to do with it.
What solved the problem was:
In the View Effects (right-most) Inspector, uncheck "Core Animation Layer" for the Window's main view.
Can anyone explain what is happening here, and perhaps improve upon the solution ?
It looks like Core Animation and NSTableView aren't getting along so well. The "fading" effect is a by-product of the way core animation works. When you have core animation in one view, it is also enabled in all of that view's subviews.
I don't recommend using core animation on the Mac unless absolutely necessary, because some interface elements (NSTextView and NSTableView, for example) aren't compatible with it. iOS has much better support for table views and such using core animation, mainly because it was designed with core animation in mind.
I know that some more simple UI elements are compatible (NSTextField and NSButton, for example).
If you absolutely need core animation in the rest of the window, put all the other views in a subview of the content view, while leaving the table view directly in the content view. You can then enable Core Animation in the other view.
Commenters, feel free to add to the list of what is and isn't compatible.
I have been trying to create a simple swipe transition. However buttons seem immune to any CAAnimation that crops.
I am trying to get it so that a bar moves across the screen and as it goes over the button it removes the part it has just gone over.
I have tried bounds.width, size.x and many other key-value paths to achieve the affect but I haven't got what I wanted. It just relocates the text which always remains entirely visible
I have also tried changing the UIButton to a UIImage but the text does not seem to print on a UIImage.
I tried using masks too but I have heard they should be used as infrequently as possible as they consume the phones resources. I didn't really get very far with this either anyway as I hadn't used them much before.
I also tried placing it in a container view and then change the dimensions of that but again all of the text remained entirely visible.
I know I could have a view hide the button but I am trying to reveal the view behind as the bar swipes.
Does anyone have any suggestions of how to achieve a swipe transition on a UIButton?
Help would be much appreciated.
Thanks
I think what you're looking for really is a mask. See the tutorial here:
http://iosdevelopertips.com/cocoa/how-to-mask-an-image.html
What I'd do in your situation is create a custom UIButton class, and add a mask as in the tutorial, then animate the position of the mask. Slide the mask of, nothing shows. Slide it on, part shows until the whole thing is visible.
Edit: I haven't really heard anything about hogging resources, especially since it appears to be simple core graphics.
Unfortunately this is hard for me to test myself because I have yet to get a Magic Mouse of my own, but I've been told by my testers who do have a magic mouse that momentum scrolling isn't working in my app. I've not subclassed NSScrollView, but scrollview's document view is all custom. I have not overridden scrollWheel: anywhere, either, and yet momentum apparently just isn't working. I'm not even sure where to begin. I thought it'd just send scrollWheel events and things would take care of themselves. (Scrolling with a wheel or on the MBP trackpad works as expected.) Obviously I must somehow be doing something that's stopping it, but I don't even know where to begin. Thoughts?
I figured this out awhile ago and the problem was that on scroll, I was doing a lot of fancy view manipulation somewhat like how on the iPhone the UITableView adds and removes views as they scroll on and off screen. This worked great for performance - but the more I got into OSX programming, the more I realized this was wrong for OSX (but the right idea of iPhone).
Anyway, what's really going on, it seems, is that when you do something like a wheel scroll, the scroll event is sent to the view that's under the mouse cursor and then it ripples down the responders/views until it gets somewhere that handles it. Normally this isn't a problem, but with momentum scrolling the OS is really just sending ever smaller scrollWheel events to the view that was under the cursor at the time the momentum started. That means if the view is removed during the course of scrolling (because it scrolls off screen or something), it breaks the chain and the momentum stops because the view that's still getting the scrollWheel messages is no longer in the view hierarchy.
The "simple" fix is to not remove the view that got the last scrollWheel event - even if it's off screen. The better fix (and the one I went with) is to not try to use NSViews like they are UIViews and instead just draw the content using drawRect. :) Not only is that about a billion times faster, it Just Works(tm) with momentum scrolling because it's how OSX expects things to be done.
Repeat after me: OSX is not iPhoneOS.. :P
Odd scrolling behavior can occur when you don't set the Line Scroll and Page Scroll properties of the NSScrollView itself.
Beyond that, you're quite simply going to have to get a Magic Mouse - easily said or not :-) - to test this yourself or post the entire code of your custom view as well as the xib containing it. There's no way others can offer you more than guesses (like the above) without it.