I'm currently working on a prototype for a todo type app. I have a table which contains the user tasks. What I want to do is only present the user with pertinent task information. But to edit additional information, they would click on a disclosure button to expand the cell.
I was thinking of two possible ways to handle this:
Expanding NSTableViewCell
Using an NSStackView as the contents of each cell
If using the NSTableViewCell, I would probably have two NSViews to represent the cell (top part and lower part).
If using the NSStackView, I'd have an easy means of encapsulating the parts.
I suppose another method could also be just building it entirely with NSStackView.
The more difficult aspect of this seems to be related to the actual expansion/collapse of the cell.
I understand this could be deemed the type of question that's asking for an opinion. I've never built a MacOS app. So I'm looking for some guidance as to the best method to approach the problem versus spinning my wheels on approaches that are destined to not be productive.
Thanks!
In the end, it looks like the best thing to do is use an NSTableCellView with two NSViews for the top and bottom half. I had the case of this as well as the NSStackView working. But in the end, I found that using NSStackView to collapse or expand requires a call to make noteHeightOfRows work anyways.
So it would initially seem that it's not worth the effort of expanding it unless I have a more complicated cell where say I wanted a top, middle, and bottom, where the middle could expand and contract. While I would still need to use noteHeightOfRows, it would allow for it.
However, there is one benefit of using the NSStackView. The animation is much smoother for the collapse. I've found the NSTableCellView method with a top and bottom NSView shows signs of "tearing" as it collapses. This is what appears in the bottom edge, while horizontal, jitters. This is particularly apparent if you either spam the button or if the cell is selected because the bottom of the outline can sometimes grow in height.
I also found that when using NSAnimationContext to help make it look a little smoother, I'd see strange behavior. Like the hide would happen at the wrong time (even though it was in the completionHandler. I think the root cause of that are what becomes overlapping animations.
Related
I edited my view with auto layout. I clicked add missing constraints. I'm working 4 inch screen on mainstoryboard. Everything looks good for 4 inch, but not the other iphone screens. I tried some ways like someone did, but I didn't fix it.
Snapshot :
This screen from iPhone 6s. Something going wrong for picker view, google ad and the others.What shoul I do? By the way sorry for black lines.
My view and UIs are here. How should I do the constraints for each every one of them? I'm really new for iphone layout. If you explain step by step basically, I really appreciate for that.
Sorry but clicking add missing constraints it's never the ideal solution, you really should understand how and which constraints you really need for your layout.
If you have clicked add missing constraints now you probably have a lot of constraints, you need to check for example your picker view which constraints it has and fix one of them or more.
So IMHO now you have two ways: post here, updating your post, the full list constraints you have for one object at least and we can try to help you, of course, I'm the first; the second solution it's clear all constraints and add one by one, understanding each rules: it could be boring at first but it will be really helpful believe me.
I would begin adding your layout constraints from the top of your view controller. You can add the constraints manually by right click dragging from the target object to another object. Most of the time, it is necessary to add at least two constraints to a view, one constraint that modifies the x coordinate of the object and another constraint that modifies the y coordinate of the object.
I would recommend using the leading/trailing space constraints and the top/bottom space constraints for all of your objects that you want to be hugging the view controller. After you make these constraints between the controller and the objects, add constraints between two objects. If all of the lines are blue or orange, you probably have sufficient and satisfactory constraints.
I have a custom NSView subclass, and I put it in a NSScrollView, and the basics are working fine. It always takes up the full width of its available space, so its constraints take up the whole width of the scroll view. How much vertical space it takes up depends on how much data it has to display, so it can scroll vertically, only. That's all great.
The catch is that if my custom view needs less space than the NSScrollView that it's in, it doesn't expand to fill the visible area. In cases where there's less data than fits in the visible area, I want it to expand downwards -- so that space is available as a drag-and-drop target, among other things.
I've tried changing its "hugging priority". I've tried adding a constraint to keep the bottom below the NSClipView's bottom. I can't come up with any constraint-based solution to fix this (though I haven't ruled out the possibility, either).
I've tried catching the notifications when the NSScrollView changes size, and adjusting the custom view's frame if it's too small, but (presumably because I can only change its current frame, while the layout system does all layout later) I can't seem to make this work, either.
Is there a trick for adding a view to an NSScrollView such that it expands to the bottom of the visible area, whenever it would otherwise be too short? It seems like it should be so simple, and I've done it before in cases where I just call -setFrame on everything manually, but once you move to the autolayout world, that approach stops working.
Without knowing what your constraints and content hugging and content compression actually look like...
Content hugging with at least one edge having >= constraint to superview might do it but you might need to adjust priorities.
You might also need to make sure you've implemented intrinsicContentSize in your custom view class this tells the content hugging and compression what they need to knowfirst.
In order to categorize a wide variety of unique views, I have an elaborate setup: main categories are selected via a toolbar, and then specific panes are selected in a category's NSScrollView. This looks like: window -> NSViewController controlling five views -> sub-NSViewController for each view controlling X views -> each view contains a core-plot graph. In short, nested NSViewControllers with a core-plot CPLayerHostingView at the end of nearly every path.
Before I even get to my question, feel free to point out that this is a poor implementation. In terms of user-friendliness, I think it makes sense, but the sheer number of nested objects makes me wonder if there's a better way.
Now then, assuming I've designed it the best possible way, the question itself: suppose I have selected a category and then a sub-item within, and am looking at a rendered graph. I desire the graph to resize appropriately if the window is resized. In Interface Builder I have done everything necessary to make this happen: everything from the CPLayerHostingView to the NSView in the main window have been set to autosize in all directions. Despite this, if I resize at runtime, the graph stays still and does not resize or move. In a design with zero or one NSView tiers this would be much simpler to debug, but I'm out of ideas in this scenario.
What tricks, programmatic or IB-based, can I use to make sure an NSView resizes according to a window resize many, many levels up?
Not only do you need to set the springs and struts, but you also need to make sure "Autoresizes Subviews" is checked.
I am trying to create a view for a kind of brainstorming application like, for example, OmniGraffle, with elements that contain textviews and can be dragged around. (Also, the should be connectable with arrows, but that is not (yet) the problem)
I did my homework and searched via google and read books about cocoa, but there seems to be no similar example around.
Since I am also new to cocoa, I’m a bit helpless here.
The thing I am sure of is, that I need a custom view in which I can create my elements - what I tried until now to do that is:
First, I searched for the syntax to add subwindows to a window to create my elements. Subwindows, I imagined, would automatically be movable and come to front and so on.
The problem: As the experienced Cocoa-programmers of you probably are not surprised, I was stunned to find nothing about anything like that - this seems to be something, that is just not intended in Cocoa?!
Then I thought about creating subviews that contain a custom view for the title bar drawing (where the user can click to drag the element) and a NSTextView.
Problems:
I read, that it is not so clever to create dozens of subviews in a window because that would be very slow (or would that be not so bad in this case because all the subviews would be instances of always the same class?).
Also I can’t find out how to load a subview from a nib- or xib-file. Would I need a viewController? Or would that make the dozens-of-instances-problem even worse?
And Apple tells you not to overlap subviews (okay, that would be not so important, but I really wonder how the guys at OmniGroup made OmniGraffle...)
Because of that, I now wanted to do the title-bar-drawing in the surrounding custom view and create the textview programmatically (as I understand, a text-“view“ ist not really a view and takes its functionality from NSCell to reduce all the effort with the views?).
Problems:
Even that failed because I was not able to create a textview that doesn’t fill the complete window (the initWithFrame: of the [[NSScrollView alloc] initWithFrame: aRect] just seems to be ignored or do I get that wrong?).
Also, there should be some buttons on each element in the final application. I imagine that would be easier to accomplish with a subview from a nib-file for each element?
Well, now that nothing works and the more I read, the more problems seem to occur, I am pretty confused and frustrated.
How could I realize such a program? Could someone please push me in the right direction?
I created a class for the draggable elements where I save position, size and text in instance variables. In my view, every new element instance is added to an array (for now, this works without a controller). The array is used to draw all the elements in a loop in drawRect:. For the text of the element I just use a NSTextFieldCell which is set to the saved text from every element in the same loop.
That way it is also possible to overlap the elements.
I’m starting to develop my first full-blown Cocoa application containing a view which I would like to behave (and look) similar to Automator’s AMWorkflowView.
The basic features I’d like to achieve:
Positioning of subviews
Display of subviews in expanded / collapsed states
Multiple selection
Drag and drop
In order to get accustomed to Cocoa, I started with a custom NSView which mainly served as a container for the custom subviews and handled their positioning and multiple selection.
The subviews are also subclasses of NSView, and contain a variable amount of views themselves, like buttons, labels and popup menus, and therefore can have different heights.
This worked quite well, but before going on, I want to make sure to have everything neat and tidy according to the MVC pattern.
I suspect that there already is a class in Cocoa that facilitates the implementation of a view container, like maybe NSCollectionView.
It seems that there is no (easy) way to display differently sized views in an NSCollectionView, though. Should I continue implementing my custom NSView (probably using an NSArrayController for selection and sorting support), or are there better ways to go?
Any help is much appreciated
Unfortunately the answer is you'll have to roll your own. NSCollectionView does not allow for variable-sized items (which also rules out expanded/collapsed states).
For a limited number of items, you can accomplish this rather easily (you just need a container view that arranges the subviews properly when asked to layout, then you need to make sure you re-layout when things change). For many subviews, however, you'll need to take care to be as efficient as possible. This can start with laying out as little as possible (only those "after" the resized view, for example) and get as complex as caching a visual representation of a prototype view, drawing the cached images (fast!) for all but the view being edited, and only using/positioning a "real" view for the view being edited.
Drag and drop works the same as it always has, but none of the above accounts for the pretty animation NSCollectionView gives you. :-) It's fast and beautifully-animated precisely because all the subviews are uniform (so the layout calculations are fast and simple). Once you add irregular sizes, the problem becomes significantly more complicated.
The bottom line: If you need variably-sized views, NSCollectionView will not work and you'll need to roll your own or find someone else's shared code, but performance and beautiful animation will not be easy.