Sizing a control to fit its container in Interface Builder - cocoa

Let's say I have a split view, and I want to fill half of it with a table view (a fairly common use case, I would think). Is there any way to tell the table view to size itself to fit the split view or do I really have to size it manually?

I've done this, the way Jon Hess mentions first. Assuming you're using Interface Builder version 3:
Drag and resize your GUI (tableview from what I understand?) component to fit into the enclosing area the way you want it.
Click it to select it.
Press Command-Shift-I to open the inspector window for this GUI component. The inspector window should now actually show that you've selected a "Scroll View".
Click the "ruler" heading to be able to set the sizing. You'll see to the right an animated representation of how your GUI component will behave within its enclosing GUI component, and to the left another represenation of the same, without animation, but with four springs and two struts that you can turn on or off.
Turn all six things on, making them red.
Voilà :-)

It's generally easier to create the subviews first, then use the Layout/Embed Objects In/Split View menu item to create the split view around them.

As far as I know, doing it manually is the only way to go. However, if you turn on "snap to cocoa guidelines", the inner view will snap to the edges of the enclosing view as you drag towards them. This makes it easier than having to manually mouse the edges into place, or manually edit the sizes to match.

You can set all of the springs and struts of the table view to "on" in the size inspector and that will cause the table view to fill the split view. Alternatively, you can use the outline view in the main document window to place the tableview's enclosing scroll view directly into the splitview instead of in an intermediary custom view.

Related

What is the appropriate UI set up for messaging functionality?

I have an app which allows users to send messages to each. The process is accomplished by saving the sent messages in a local SQLite database, while actually sending the messages to a database and using push notifications to send the message to the recipient's SQLite database. The set up I have works fine. However, what I am confused about is how to set up the actual interactive UI for the user (I am using XCode). I figured it should be a UITableView with each table cell representing a message. However, with this approach I run into a few requirements:
Variable TextView Sizes
Just as with regular iOS messaging, the TextView's size needs to be variable, adjusting its dimensions to fit all of the text in each message. I do not know how to accomplish this. I have a general understanding of how to generally vary sizes, but no clue how to dynamically have it based on the text within that view.
Variable TextView Positions
Again, just as with regular iOS messaging, the textview needs to be offset to either the right or left side depending on whether the sender was the user or who the are conversing with, respectively. I also do not know how to do this, because it changes the center of the textview.
Non-selectability
Xcode allows cells to be pressed. Handling what happens after this selection can be achieved by the didSelectRowatIndexPath tableView function. I can simply not implement this, but clicking on the cell causes it to turn darker to indicate it has been pressed. I would like to eliminate this while retaining the ability to, say, select some of the text and copy and paste it or whatever (just like messaging works normally on your phone).
Other Approaches?
This is the real meat of the question. I have considered the above approach because that is all that I have been able to come up with based on my limited experience with XCode UI elements. If there is a better approach (perhaps even a pod or framework) for this purpose I would love to hear it. I do not need the messaging UI to look amazing, just clean and crisp.
I suggest the following:
Variable TextView Sizes:
I assume you do use auto layout. If you don’t yet, please consider using it since it make life much easier!
If you use a UITableView, you can adjust the height of its UITableViewCells dynamically, depending on the actual content by using self-sizing cells. You can find a tutorial how to do this here.
Variable TextView Positions:
I assume you have a UITextView within a table view cell. In this case, you have to set auto layout constraints to the borders of the cell’s contentView. If you define a custom subclass of a UITableViewCell, you can define in this class 2 IBOutlet properties that are linked to say the left and the right layout constraints (e.g. var leftLayoutConstraint: NSLayoutConstraint). Then, you can set the constraint’s constant property as required when the cell is laid out, i.e. in the layoutSubviews function of the custom table view cell.
Non-selectability:
I am not sure what you mean by „I can simply not implement this“. Please make sure that you set the delegate property of the UITableView to the view controller where you want to handle cell selection. Selecting a cell changes the cells color by default, but you can change this: In the storyboard, select your table view’s prototype cell, and open Xcode’s utility pane (top rightmost button). Under „Table view cell“ you find „Selection“ that you can set to „None“.
I hope this helps!

Build a Cocoa UI for OSX

I'm trying to build a UI which look like this:
I'm using a storyboard with Xcode but I don't know how to start. I think a need different view in the window to manage button, text and tree but I don't know I to do it. I have try to use a split view but it gave me only 2 views instead of 3.
Any help in Cocoa and storyboard is welcome.
Thanks
Can't see where you'd want to use an NSSplitView but the UI you're attemting to create is trivial -
A plain NSWindow with the toolbar items configured as per your screenshot.
An NSOutlineView for the tree view with the three columns,
the content border of the window sized accordingly to make room for the label you intend to put at the bottom of the window.
As mentioned in the comments one way to populate the outline view would be to use an NSTreeController and Cocoa bindings. That's probably the only slightly more complicated bit about this UI..

How to call NSScrollView autoscroll-method programmatically

I have simple chat application with text messages view-based NSTableView as you can see at the picture below.
Each message contains NSTextView instance having height to fit all the text.
All I need is to start NSScrollView (which NSTableView-instance is enclosed by) autoscrolling while the user selecting text dragging mouse far enough. Unfortunately, autoscrolling doesn't appear. In case of dragging somewhere outside of the text views all succeed.
I tried to call autoscroll:-method directly by simply push NSEvent-instance from NSTextView-subclass "mouse dragged"-event (like in example from this article):
- (void)mouseDragged:(NSEvent *)event
{
[self.scrollView autoscroll:event];
}
As I've overrode all the mouse events and implemented all the text selecting, this method often invokes. But the autoscrolling doesn't seem to work.
UPDATE
I figured out that before calling -autoscroll:-method there must be -mouseDown: of the same object. But it breaks my text selecting mechanism. The point even not in being first responder, there must be nothing but the mouseDown:-method.
Normally, a text view is within a scroll view of its own. Even if that's big enough to show all of the text without scrolling, it's still there. A call of -autoscroll: on anything within that scroll view (possibly including that scroll view itself?) will just try to scroll that scroll view, not the scroll view that contains the table view.
Try calling -autoscroll: on a view higher up in the hierarchy. Either self.scrollView.superview, the table cell view, or the table view.
Note, though, that the table view's scroll view will keep scrolling even after the cell view containing the text view is fully on-screen. In fact, it may keep scrolling it so far that it's off the screen in the other direction. Basically, it doesn't know that you're trying to select within the text view so it doesn't know to stop when the selection extends all the way to the edge of the text view.
Another approach might be to try to use a "bare" text view with no enclosing scroll view. I don't think IB will let you do that, so you'd have to do it programmatically. Bare text views don't play well with auto layout, though.

Cursor above siblings

Suppose there is a window with a very simple UI hierarchy which has just two siblings: NSTextView and NSButton, and they do overlap.
My question is, why is the cursor different when hovering over the button, depending on whether there is the textview below it or not? Why is the text cursor "leaking" through the button? How do I make the button retain its cursor regardless what is beneath it?
I thought I could create an NSView, place the button inside it and somehow make the view "opaque" but I didn't get too far...
What I'm trying to do is to have a button which "floats" above the textview and still displays the proper (normal) cursor.
https://developer.apple.com/library/mac/documentation/Cocoa/Conceptual/CocoaViewsGuide/WorkingWithAViewHierarchy/WorkingWithAViewHierarchy.html
For performance reasons, Cocoa does not enforce clipping among sibling
views or guarantee correct invalidation and drawing behavior when
sibling views overlap. If you want a view to be drawn in front of
another view, you should make the front view a subview (or descendant)
of the rear view.
You can use NSTrackingArea to update cursor manually:
https://developer.apple.com/library/mac/documentation/Cocoa/Conceptual/EventOverview/TrackingAreaObjects/TrackingAreaObjects.html

make NSRect selectable

Is there a simple way to create a selectable NSRect in Cocoa? In need a rectangle that can be selected and stays selected after a mouse click.
Thanks.
NSRect is just a struct with a position and size. It's not an object that can actually do anything or have any properties other than a width and height. It sounds like what you want is to create an NSView that can be selected. (Here's Apple's Guide on the subject.)
Though not as immediate as you would like, you may be interested in the management of tracking rectangles and tracking areas performed by NSView class.
This mechanism allows you to define specific areas of your custom view. Then, an event is generated whenever the cursor enters or leaves the area, or a mouse button is pressed in this area (-mouseEntered:, -mouseExited:, -mouseDown:, -mouseUp:, -mouseDragged:, ... of NSResponder class). This up to you to define what you want your application do in response to these events (set the rectangle as selected and display it accordingly).
For an example implementation of this, take a look at the Sketch example included with the Apple developer tools (look in /Developer/Examples/AppKit). Sketch allows the user to create new graphics (including rectangles, but also ovals, lines, and text), select them, move them around in the document, etc. In particular, you'll probably want to look at the SKTGraphic class, which represents a single graphic object in the document, and the SKTGraphicView class, which is an NSView subclass that perform the actual layout and drawing, handling mouse events for dragging views around, etc.

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