I have the following issue in my iPhone app.
I have 4 buttons in my IB also linked to my UIViewController (IBOutlet)
When I for example hide the second button which is AfvalSoorten with [self.btnAfvalSoorten setHidden:YES]; then it disappears, that's what I want, but I still got the button space when I debug the app on the simulator.
How can I get rid of that?
Below there is an example.
Is there an option on the Storyboard for the buttons to clip together?
You should use autolayout. Otherwise it's a nightmare with the new screen sizes.
With autolayout you can do what you ask programmatically: setup the buttons with certain constraints and then when you decide to hide the button remove the constraints that are not needed. It's flexible and powerful but not the easiest way for a beginner.
One simple way to do it is with additional constraints. For instance, if you have buttons 1, 2 and 3 (see screenshot), and you plan to remove button 2, you can add an extra constraint between 3 and 1:
That constraint should have less priority (250 in my example) than the others (1000 by default). That mean that the constraint won't be applied when button 2 is in place (with higher priority constraints).
Then, remove the button instead of hiding it.
[self.button removeFromSuperview];
When you hide the button it still considered by the layout system to take decisions, and it makes layout more complex. If you want to keep the button around make sure it's using strong modifier in the property declaration.
A better approach for above scenario - You dont need to set any autolayout or frames :)
Use UITableView and create custom cell with UIButtons in it.
Set UITableViewCellSelectionStyle to None
Here your button background is same for all cell
Create an array with above button titles
When ever you want to hide buttons just remove it from array.
The modern preferred way of doing so is to use Stack Views. Great tutorial. Requires iOS 9.
You'll find the icon of stack view in the Auto Layout toolbar at the bottom right of the storyboard canvas.
You had just make it hidden.
You have to set the frames according to your need.
OR
You can set autolayout.
maybe there is a solution with autoLayout in IB but I'm not sure about that. Programmatically you can add all your button to an array in order. and whenever you hide a button or not you loop trough the array of button and each time you find one that is not hidden you set the y coordinate on the frame to a a value and you increment this value by what you need so the next not hidden will be placed according to the last position used.
You can add the buttons programmatically -> you will have the array
of Btns and method to add array to the view controller.
You can play with the Constraints and set Height Constraint for 2nd button when hide it to 0 but all buttons should be connected with the constraints in this case.
Related
I used to be able to do this:
UIButton *bigBottomBtn=[[UIButton alloc]initWithFrame:CGRectMake(0, self.view.frame.size.height-60, self.view.frame.size.width, 60)];
I also used to be able to just drag a button onto a storyboard and add a constraint that would hold it to the bottom of the parent.
What is going on with Xcode, Autolayout and Apple for that matter....is my Xcode not working properly? Have I missed a major memo? is Apple just going downhill fast?
Your button-creating code used to work (and still does) if self.view's frame was correct at the time you created the button. Note that the view doesn't necessarily come out of the xib or storyboard with the correct frame; the xib/storyboard contains the view at some design size which might not match the current device. This wasn't as much of a problem when all iPhones had 3.5 inch screens, but became a pretty common problem with the advent of the iPhone 5's 4 inch screen.
The view isn't guaranteed to have its correct frame until its superview's layoutSubviews returns, so if for example you're creating bigBottomBtn in viewDidLoad, that's too early. Many questions on stackoverflow cover this problem. You either need to set the autoresizingMask of the button, or implement layoutSubviews or viewDidLayoutSubviews to update the button's frame, or turn off translatesAutoresizingMaskIntoConstraints and install constraints. Note too that your view can change size if you support rotation, slide over or split view multitasking, or if your view can be the detail view of a UISplitViewController, so it's a bad idea to try to guess the correct frame of the button based on the device's screen size at the moment the button is created.
Note that storyboards now by default use a design size of 600x600, which isn't the size of any device. This is probably because if Apple chose some device's size (say, the iPhone 5's 320x568) as the default, and you happened to use a device of that size as your primary (or only) test device, you could easily forget to think about what your app will look like at other sizes. However, you can explicitly set the design size to some device's size if you want:
I usually use “iPhone 3.5-inch” if I don't specifically need something bigger, because it lets me get the most scenes on the screen simultaneously (and produces the smallest screen shots for stackoverflow).
As for “I also used to be able to just drag a button onto a storyboard and add a constraint that would hold it to the bottom of the parent”, I have good news: you still can. Example:
However, you do need to be careful if you have filled your root view with a table view as appears to be the case in your screen shots. You need to drag the button to the document outline in that case, because if you drop it on the table view, Xcode will assume you want it to be the table view header:
Trying to pin a table view header to the bottom of the screen would be folly.
As for the Editor > Align menu, I have found that the items can be mysteriously inactive, which is frustrating.
Note, though, that only the “Horizontally in Container” and “Vertically in Container” will work (when they work at all) with a single view selected. To use the other items in the menu, you need to have at least two views selected, because the other items align the selected views with each other by setting their frames:
If you only have one view selected, Xcode doesn't know what other view you might want to align it to.
Those menu items are perhaps useful in the springs'n'struts model, but they don't add constraints, and under autolayout you probably want constraints to enforce the alignment at run time.
As far as I know, those menu items have never added constraints, but I'm not going to reinstall Xcode 6 to verify that, because there's a convenient popover that will add constraints corresponding to all of those menu items:
In xcode you always need to add buttons according to its visibility. As you said you need to show button on top of tableView and it should be aligned to bottom. For that You just need to arrange the order of items. as shown in the image below.Provide the layout for the button.
My application gathers input from users and hence it is full of Labels, text boxes and buttons and I have to show or hide set of labels and text boxes based on certain conditions.
To accomplish it, I did the following.
Set fixed height (lets say 30) for all the controls
Set height constraint on each of the controls and created an outlet to the height constraint in the ViewController
Alter the heightConstraint.constant value programatically (between 0.0 and 30.0) based on the scenarios.
Having programmed like this, it is very difficult for me if there is any change in layout. (i.e., if user requested to add/remove any particular control from the view Controller).
I am using Auto Layout constraints. Could anyone suggest if there is a better way to accomplish my goal.
I am using IOS9 and Swift.
Many thanks in advance.
You can use UITableViewController with static cells for this case.
For hide/show row or section, you can change the size in the tableView:heightForRowAtIndexPath method.
UITableViewController automatically manages the layout and with static cell you can even create outlet for all the controls.
Have you considered using a table for this? It has mechanisms for inserting and deleting rows and would manage the layouting for you - only part you'd need to care about are the contents of the cells.
Instead of making IBOutlets to the height constraints of all the views that you might need to hide, you can just use the hidden property of UIViews to hide/show the view.
In case you need the view to make space for other views, you could set a simple animation and move the view out of screen bounds. You might face issues with layout constraints but it's surely worth the effort from a UI/UX perspective.
Additionally, if you know that you don't need a view any more you can even remove the view from it's superview.
I'm looking for customized solution.
I have these two buttons with their constrains
I want to swipe their places During run time.
I've tried the translatesAutoresizingMaskIntoConstraints option but it's misbehave in many scenarios.
also I can't just outlet some constrains and change their constants during run time because the two buttons are related to each other
What to do ?
If you just want position of both button to change and not to perform any animation, then you can simply swap the background color and title text of next/back buttons. You would also need some extra logic to handle actions of both buttons after the swap.
In that way they will appear swapped
I am hiding the second button below, but I want the top button to drop down. Is there a way to do that where it has a relative layout.
Yes you can do this. One of my project I had to do this. If you are using autolayout then you can not manually change your buttons frames. You can either have to disable autolayout, or modify the constraints programmatically. I followed the first one.
In your case, if you want the first button to take the position of the second one (which you are hiding) then take the frame of the second button and assign it to the first button.
Hope this helps. :)
I have a UIView, defined in a nib, and I need to be able to show/hide a middle button in that view. When I show the button, I need to reposition the two bottom buttons below it, as well as make the view taller to make room for everything. When I hide the middle button, I need to move the two bottom buttons up and vertically resize the view to make it less tall. I do NOT need to animate any of this since it the changes will never occur while the view is visible to the user.
I'm new to iOS and I'm used to using Autolayout, but I can't use Autolayout in this case to handle this automatically, so my current approach is to hardcode the frame position and dimensions for the two bottom buttons for each of the two different situations. I'm also hardcoding the two different frame sizes for the view itself. In viewDidLoad, I determine if I need to show/hide the middle button and set the frames for the view and bottom buttons appropriately. This works, but if feels hacky. Is there a better way I should be doing this?
Thanks in advance for your wisdom!
You don't need to hardcode your frame sizes in viewDidLoad. The only thing you should take care of is determining that whether you need to show you middle button or not. Within the implementation file where you are allocating your UIButtons, check if the middle button has to be shown, if Yes allocate it, if not then don't. The frames of two buttons and the view should contain a factor which can set/size them accordingly.
You'd basically be managing the Auto-layout programmatically. And if you're not even allowed to that then whatever else you'd end up doing would pretty much be a hack.