Ok, this is more good information to keep in mind when designing autolayout constraints. Given that my design isn't animatable, it's back to the autolayout drawing board. Again.
Doug Hill > On Dec 14, 2016, at 3:07 PM, Gary L. Wade <garyw...@desisoftsystems.com> > wrote: > > Right, activate and deactivate are not animatable, but the constant values in > constraints are. > > True, it depends on what you’re showing as to whether to shrink or move your > view. When I wanted to use a search bar in UISearchController with a > collection view in iOS to appear similarly as UITableView, I moved the search > bar: > > https://whatweretheythinkingblog.wordpress.com/2016/11/19/effectively-using-uisearchcontroller-with-uicollectionview/ > > <https://whatweretheythinkingblog.wordpress.com/2016/11/19/effectively-using-uisearchcontroller-with-uicollectionview/> > > When I wanted to show an icon to the left of a title, where the item may not > have an icon but was only available through a REST call, I found it more > attractive to grow the icon and compress the title in that animation, > choosing a scale-to-fill option, when I determined there was an icon. > -- > Gary L. Wade > http://www.garywade.com/ <http://www.garywade.com/> >> On Dec 14, 2016, at 2:52 PM, Doug Hill <cocoa...@breaqz.com >> <mailto:cocoa...@breaqz.com>> wrote: >> >> Gary, >> >> Thanks for the reply. >> I tried moving the container rather than resizing to 0 because there's a >> table inside this view and it will relayout when resizing. For an animation, >> I guess it depends on what effect you want: either seeing the view move or >> resize to 0. >> >> Oddly, when I put my code to activate/deactivate constraints inside a >> [UIView animateWithDuration…] I get no animation. :( >> >> Doug Hill >> >>> On Dec 14, 2016, at 2:49 PM, Gary L. Wade <garyw...@desisoftsystems.com >>> <mailto:garyw...@desisoftsystems.com>> wrote: >>> >>> If I understand you correctly, you might prefer the approach I chose to do. >>> Rather than activating and deactivating constraints (BTW, you should >>> always deactivate before having multiple actives), set your constraints up >>> to always be active but change the width for the one you’re hiding to 0 and >>> the other to be the extra size needed to fill the gap. I also chose to >>> animate the constant values, so the size-change is smooth to the user. >>> -- >>> Gary L. Wade >>> http://www.garywade.com/ <http://www.garywade.com/> >>>> On Dec 14, 2016, at 2:19 PM, Doug Hill <cocoa...@breaqz.com >>>> <mailto:cocoa...@breaqz.com>> wrote: >>>> >>>> I'm seeing warnings in the console when I dynamically make autolayout >>>> constraints active/inactive at runtime. >>>> >>>> I have two constraints that align a container view leading or trailing >>>> edge with another view's edge. This is to move the container onscreen or >>>> offscreen. I have another view whose trailing edge aligns with the leading >>>> edge of the first container view so it moves with it as autolayout >>>> constraints change. >>>> >>>> At runtime, I make one of these constraints active and the other inactive, >>>> like so: >>>> >>>> - (IBAction)toggleCommentsVisibility:(id)sender >>>> { >>>> self.commentsAreHidden ? [self showComments:self] : [self >>>> hideComments:self]; >>>> } >>>> >>>> - (IBAction)showComments:(id)sender >>>> { >>>> self.showCommentsConstraint.active = YES; >>>> self.hideCommentsContainerConstraint.active = NO; >>>> >>>> self.commentsAreHidden = NO; >>>> } >>>> >>>> - (IBAction)hideComments:(id)sender >>>> { >>>> self.showCommentsConstraint.active = NO; >>>> self.hideCommentsContainerConstraint.active = YES; >>>> >>>> self.commentsAreHidden = YES; >>>> } >>>> >>>> When I call showComments, I get the following warning in the console: >>>> >>>> ===== >>>> >>>> Unable to simultaneously satisfy constraints. >>>> Probably at least one of the constraints in the following list is one you >>>> don't want. >>>> Try this: >>>> (1) look at each constraint and try to figure out which you don't >>>> expect; >>>> (2) find the code that added the unwanted constraint or constraints and >>>> fix it. >>>> ( >>>> "<NSLayoutConstraint:0x7f91426a3ef0 'CommentContainerProportionalWidth' >>>> UIView:0x7f91426d9db0.width == 0.33*UIView:0x7f91426def30.width>", >>>> "<NSLayoutConstraint:0x7f91426c91e0 'Hide Comments Constraint' >>>> H:[UIView:0x7f91426d7f00]-(0)-[UIView:0x7f91426d9db0]>", >>>> "<NSLayoutConstraint:0x7f91426e2990 'ShowComments' >>>> UIView:0x7f91426d9db0.trailing == UIView:0x7f91426d7f00.trailing>", >>>> "<NSLayoutConstraint:0x7f91427e43c0 'UIView-Encapsulated-Layout-Width' >>>> H:[UIView:0x7f91426def30(768)]>" >>>> ) >>>> >>>> Will attempt to recover by breaking constraint >>>> <NSLayoutConstraint:0x7f91426c91e0 'Hide Comments Constraint' >>>> H:[UIView:0x7f91426d7f00]-(0)-[UIView:0x7f91426d9db0]> >>>> >>>> Make a symbolic breakpoint at UIViewAlertForUnsatisfiableConstraints to >>>> catch this in the debugger. >>>> >>>> ===== >>>> >>>> This is puzzling because IB doesn't give me any autolayout errors/warning >>>> when I manually activate/deactivate these constraints. Also, I don't get >>>> this runtime warning when calling hideComments, only the 'show' case. >>>> Finally, things actually work at runtime because it's nice enough to >>>> "break" the constraint that I deactivated in code. But I would like to not >>>> have these warnings. >>>> >>>> Any ideas on what's going on how I might go about debugging this? >>>> >>>> Doug Hill _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
