This is the most complicated UI related problem I've come across yet. I've been trying to find a solution for literally weeks but no avail. Let em explain.
In this app I'm working on, I need to display a certain list. It's actually a schedule. Here's how it should look like,
The fields circled by red circles don't change. To explain what change means I have to show you this.
Its a set of filters which the user can show/hide certain fields and the ones that are circled in the first image are static ones. They can't be toggled on and off.
Now the problem arises with the ones that can be toggled. Here's what it looks like if you turn off the Show Actions flag.
A new label with a blue background replaces the bottom one you can see in the first image.
Here's another one where you disable Show Time option and the time labels are gone (yes it affects only for some. Its expected).
If this filter list were an option list, it would have been easy. Just create a custom cell for each option and you're good to go. But unfortunately the user is able to toggle multiple filters! For example the user can turn off both Show Actions and Show Time and it'd look like the last image but the bottom label would have the blue label in the third image.
To top it all off, the cells' height is dynamic. In iOS 8 creating self resizing cells are easy enough from the IB when you could just add auto layout constraints and done.
But it seems to me that creating these cells from the IB isn't an available option to me. Simply because there are way too many filter combinations a user can make. So the cell's subviews need to adjust to it.
My question is how can I create a dynamic cell like that? My best guess is through code, right? I haven't written my UI in code before so I tried creating a test project to familiarize myself with it. But the problems I'm facing is setting fixed frame sizes makes the dynamic nature obsolete. And how can I move a view to fill up a removed view's space (Last image. Time labels are gone so the name and the id labels move to the left to fill that space).
I know this question is a little too broad. I'm not asking for a straight answer either. I'd really appreciate some pointers, or even a better suggestion on how to approach this because I'm truly at the rock bottom on this issue.
Thank you.
It's hard to give you any precise help since your question is so broad. First, I would recommend watching the 3 videos on Auto Layout from the WWDC 2012 (sessions 202, 228, and 232).
To answer your one example, how to move a view to replace a view that's removed. You would need to make two left edge constraints from the view with the text (Kund Alof...). One with a constant of 0 to the time label with a priority of 1000 (that's the default), and another to the left edge of the cell, also with a constant of 0, but with a lower priority, say 900. As long as the time label is present, the constraint to it will determine the position of the text label, but when it's removed, the lower priority constraint to the left edge will take over and move the label over to the left edge.
Related
My use-case is like this:
The user defined some tags (text like "#asdf", "#qwerty", "#let_me_think_about_it" and "#decide later"). I want to display these in a box without scrolling (and don't know, how many tags the user created until I display the box).
The box itself should not be scrollable at all but be shown in a UITableViewCell (which is being scrolled). So it must compute the proposed height and respond to Autolayout mechanisms. If a (ARM) Mac user resizes the window to be smaller than before (or an iOS user rotates the device), the box should increase/decrease its height, as necessary (within the limits of Autolayout, since I know of some issues). Each of the tags should be (de)selectable at the same time (UILabel with UITapGestureRegognizer attachted?) and be able to displayed 'selected' (via a background view).
So, the box should primary try to align all content horizontal. If There's not enough horizontal space, do a "line break" and continue on the next "line".
My current solution is a UIScrollView that the user can scroll horizontal and tap any of the (UILabel) views. The displayed views itself are being loaded from a NIB file, like a UITableView does. The issue here is that not any of the selected tags might be visible at the first glance.
If there was no Autolayout, I'd exactly know what to do. But since there it is, I want to use Autolayout in my NIB files and wonder what you would do?
(How do you compute the required width of such a view and decide when a line break is to be done (and how?))
I think I need a simple hint. But if it needs code to explain, ObjC and Swift is both acceptable. :-)
So, the box should primary try to align all content horizontal. If There's not enough horizontal space, do a "line break" and continue on the next "line".
This sounds like a job for UICollectionView with UICollectionViewFlowLayout. You can disable scrolling, and the layout object will tell you the size of the content so that you can adjust the size of the box.
(How do you compute the required width of such a view and decide when a line break is to be done (and how?))
If you're doing it yourself, you add up the widths of all the items on the first line, and if it's larger than the available space, you move the item that extends past the limit and any subsequent items to the next line. Repeat as needed. But that's exactly what a flow layout does for a collection view, so there's no need to roll your own.
I am working on auto layout and making those UIIMages as Button.
I would like to make those button to be clicked and switch the images
as well as showing some words in the label.
In this case what should I do?
In addition, as it is shown, the auto layout ratio is different only from the iPhone SE. In. this case What should I consider?
Many thanks,
The first thing you need to learn is auto layout. Start with basic Always go with Apple's doc first
This one I likes he is good and you will also find how to use buttons as image view, using card game example, check other tutorials also very helpfull.
Stanford university autolayout by Michel Deiman
As far, your question just gives your label Horizontal in the container constraints(open storyboard in the right bottom third from last (allin) click on it popUp will open), and 20 bottom to the buttons and it will be in the centre. Every elements need x,y height and width so it knows exactly where to place, so you also need to give constraints to the buttons, Learn stackView to understand how to place your button without giving many constraints to each button and stack view will handle it for you, try hide and show to one of the button and magically stack view will adjust all adjustment. I suggest before staring Do read apple's doc first.
And Your question is too broad to answer, so read and try adding different constraints based on your need and ask a specific question(after trying by yourself) like why this label getting cut what constraints should i add so people know exactly what you want to achieve, people are always ready to help, just ask the right question.
happyCoding
Swift 2.2 Xcode 7.3.1. iOS 9. Storyboard. I have 7 rows of four labels across. I was intending to select each row to place it in a stack. Saw this technique in Hagerty's iTunes U (Stanford). Each time I select a row and press the button to add the four across to a stack, it makes these huge rectangles... They have a width of 127,000,000. I keep trying different things, adding all suggested constraints, getting rid of all contstraints, etc.
Any idea what I am doing wrong? TIA
Sorry, I'm apparently not allowed to add images as yet here... The rectangles on the View Controller are all UILabels. When I select a row of them and press the Stack button, next to pin, etc., it appears to make one wide rectangle, all 4 on top of each other, this last time is was 27,216,026 pixels across. I think the comment about not using "suggested" constraints is probably a clue... there certainly seem to be more than necessary. There are also some where I tried to delete a constraint where the constraint item appears to be dimmed. There are one or two where the dimmed one, and an exact copy of the dimmed are both there...
There are no images on the view... the only button is up top, a "Back" button.
Someone gave me the clue. It turns out that there are some bugs in the constraints setup, especially when using "suggested" constraints. I deleted all the constraints, then added just the minimum needed, made sure they were all perfect, and I got one row to work properly. Now I can do the others.
After I do this enough times I am sure it will make sense, there is probably one constraint mechanism that doesn't work as it should - an Xcode bug. One adds size constraints both in the size inspector, and potentially the constraint mechanism, and sometimes they do not match. Those things have to be fuddled with until they do... and then Stacking works...
I've been doing iOS for a while now, but when it comes to dynamically hiding / showing elements, I'm a bit lost.
Coming from Android, I'm used to being able to simply set views to visibility gone, but this doesn't exist on iOS.
So let's say I have the following scenario:
Basically I want to have a table, but the table should not fill the entire view controller. Instead it should leave place for optionally either a button, a multiline label, or possibly both at the bottom (if visible, these should be fixed, not scroll).
One way to solve this would be to use auto layout and modify constraints, like adding a zero height constraint. But that would make iOS kill one of the other constraints, which would make it hard to change it again. For the label, I wouldn't always want to have a height constraint, because it could be multiline, and should take the size it needs.
Maybe it's easier to skip autolayout here and modify frames instead, I don't know.
My question is: What approach would be best here?
Is there some other way of doing this I haven't thought of, or do I have to try to do what I described above?
I'm not primarily looking for code (code can be ok), but I'm more interested in a description of how it can be done.
I'd like to support iOS 7.
This problem had a variety of solutions, and opinion based, but I'm facing such questions a lot, when I don't know what to choose and what would be the "right thing".
So, I my opinion, the best solution here is using autolayout, you need to set height of label manually, but you have a few methods for this, at least you can play with it and if you don't succeed ask question about it. Using frames, you'll face same problem of calculating height, right? But with auto layout, you only need to set height, vertical space to 0, when you need to hide message.
You can also use constrains with priority lower 1000, and remove completely constraints from message (button, label) if you don't need it at all anymore.
For example, taking your layout image, you can make UIView with subviews: button, label. Top constraint connect to the UITableView, other constraints to the sides.Label and button will calculate the view's height. The only question here is label height.
So in ios assuming that the background of both these objects is opaque only the front most view in the Heirarchy will be visible and interactable, An easy solution would be to change the different frames of these two things you need and make sure they are in the back of your view heirachy, and when you need them to appear use view.bringSubviewToFront(mySubview) and view.pushSubviewToBack(mySubview) to make it disappear again. View obviously would be referring to main view of your view controller.
I'm trying to create a custom accordion-list. On tap it should expand the tapped line and the next lines should change their position relative to the expanded one. By tapping it again it should contract. By tapping another non-expanded line, the expanded line should contract and the tapped one should expand.
I tried to solve this by using subviews with TapGestureRecognizers. I have a undefined number of lines. On tap I change the height of the tapped line and rearrange the position of the following lines manually. Now, it's getting really confusing to handle all possibilities of expanding/contraction/positioning. I'm looking for a more comfortable way to handle this.
Is there any way to align the subviews vertically so that the positions of the lines change automatically if one height changes?
I think a better solution is to use the tableView where the cells will contribute your custom view.Positioning and all will be handled by tableview itself.
If you are working with iOS 6, this should be pretty easy with constraints. Specify that each view is to be located a certain distance from the bottom of the one above it, and when the ones above it move or expand or contract, that constraint should force everything else to move to keep the gap you specified.
EDIT: I just realized that you mentioned in your OP that you may not know for sure how many views you are going to need ahead of time. That probably makes the table view method others have suggested more favorable. It is still possible to do with constraints though (and I found a pretty detailed tutorial here that goes over everything).