TSStackView

TSStackView is an NSStackView subclass that observes the -hidden property of its subviews to determine if a given subview should be included in the stack layout.

The subclass retains all views passed to setViews:inGravity and performs layout as required when subview visibility changes are observed. This behaviour mimics the behaviour of the WPF StackPanel.

The -scrollViewContainer property can be used to create and retrieve a NSScrollView instance that wraps the stack view.

A simple demo project illustrates a stack of vertically expanding NSTextViews embedded in an NSScrollView.

Usage

- (void)awakeFromNib
{
	// add subviews
	[self.stackView setViews:@[self.headerView] inGravity:NSStackViewGravityTop];
	[self.stackView setViews:@[self.childView1, self.childView2, self.childView3] inGravity:NSStackViewGravityCenter];

	// we want our views arranged from top to bottom
	self.stackView.orientation = NSUserInterfaceLayoutOrientationVertical;

	// the internal views should be aligned with their centers
	self.stackView.alignment = NSLayoutAttributeCenterX;

	self.stackView.spacing = 0; // No spacing between the views

	// have the stackView strongly hug the sides of the views it contains
	[self.stackView setHuggingPriority:NSLayoutPriorityDefaultHigh forOrientation:NSLayoutConstraintOrientationHorizontal];

	// have the stackView grow and shrink as its internal views grow, are added, or are removed
	[self.stackView setHuggingPriority:NSLayoutPriorityDefaultHigh forOrientation:NSLayoutConstraintOrientationVertical];

	// toggle subview view hidden property
	[NSTimer scheduledTimerWithTimeInterval:1 target:self selector:@selector(foo) userInfo:nil repeats:YES];

	// wrap the stack in a scroll view and ...
	NSScrollView *scrollView = [stackView scrollViewContainer];
}

- (void)foo
{
	// Suspending layout only of benefit when mutating several subviews
	[self.stackView suspendAutoLayoutWhenSubviewVisibilityChanges];
	self.childView1.hidden = !self.childView1.isHidden;
	self.childView2.hidden = !self.childView2.isHidden;
	[self.stackView resumeAutoLayoutWhenSubviewVisibilityChanges];
}

Auto Content Size Options

A TSStackView instance can optionally resize to match its content. This is useful when displaying an expanding list that should not clip e.g: a list of optional email addresses. Both height and width auto content sizes are supported.

// StackView will resize 
self.stackView.autoContentSizeOptions = TSAutoContentSizeHeight;

Intrinsic Content Size Options

This is implemented but -autoContentSizeOptions should be preferred.

NSStackView has no intrinsic content size. A TSStackView instance can optionally report an intrinsic content size equal to the unclipped content size of all visible views.

// StackView will report an intrinsic height equal to the combined height of all the contained views
// plus the edge insets and view spacings (default or custom).
self.stackView.intrinsicContentSizeOptions = TSIntrinsicContentSizeHeight;

Build requirements

OS X 10.9 64bit ARC

Licence

MIT