Swift 4 reverse change height of a UIView - uiview

I would like to build a progressbar. I took a rectangular view (progressBarBckgr) and put another one in front of it (progressBar).
The one in the front should increase its height by tabbing on the correct answer within a quiz app.
func updateUI () {
let numberOfAllQuestions = allQuestion.questionList.count
print(numberOfAllQuestions) //prints 3
let progressBarBckgrHeight = progressBarBckgr.frame.size.height
let progressBarBckgrHeightInt = Int(progressBarBckgrHeight)
let progressBarBckgrHeightPiece = progressBarBckgrHeightInt / numberOfAllQuestions
progressBarOutlet.frame.size.height = (progressBarBckgr.frame.height) + CGFloat (progressBarBckgrHeightPiece)
}
So with every correct clicked answer the progressbar should increase just so far, that in the end of quiz the whole backgroundprogressbar is covered.
Example:
10 Questions
-> clicked answer fills increases the progressbar's height for 1/10
In addition to that i would like to increase the bar from the bottom to the top. As i enter the property height to increase it, it only gets bigger in direction bottom. Is there a nice turnaround trick?
Thanks!!!

You also need to move the view up by the amount of height you have increased (progressBarBckgrHeightPiece)
Also, you should set the frame directly.
progressBarOutlet.frame = CGRect(x: progressBarOutlet.frame.origin.x,
y: progressBarOutlet.frame.origin.y - progressBarBckgrHeightPiece, // Notice here
width: progressBarOutlet.frame.width,
height: progressBarOutlet.frame.height + CGFloat(progressBarBckgrHeightPiece))

Related

Why does slides[i].frame print a different value than SlideScrollView.subviews[i].frame

I was trying to calculate the current visible "Slide" in my UIScrollView when I noticed this. I couldn't figure out why I am getting these values. Especially frame 2 & 3 show strange values.
can anyone tell me if and where I am wrong and how do I get the bottom values to match that of the top?
Here is my code :
{...}
for i in 0 ..< slides.count
{
slides[i].frame = CGRect(x:CONSTwid * CGFloat(i),y:0,width:CONSTwid+20,height : view.frame.height)
print("slide \(i) frame : \(slides[i].frame)")
SlideScrollView.addSubview(slides[i])
}
let container = CGRect(x: SlideScrollView.contentOffset.x, y: SlideScrollView.contentOffset.y, width: SlideScrollView.frame.size.width, height: SlideScrollView.frame.size.height)
//this was just to see the result (do not ask me to loop it...I know :-P)
print("sr \(container)")
print("srcz\(SlideScrollView.contentSize)")
print("slide 0 frame \(SlideScrollView.subviews[0].frame)")
print("slide 1 frame \(SlideScrollView.subviews[1].frame)")
print("slide 2 frame \(SlideScrollView.subviews[2].frame)")
{...}
here is the output :
Console Output :
Thanks in advance
Since slides is an array of views you wan't to check then that is the array you need to use. Although subviews is opened property it can still hold views you should not be looking into. Basically any view can have any number of subviews for any reason. This may even vary between devices or OS versions.
In your case you seem to have an extra view of size 2.5 x 7 that looks like a very small view. Perhaps a scroll indicator?

Gap between overlaying views in swift

I was wondering how I can get a gap between overlaying views in swift. This is really hard for me to explain so I added a couple images to explain what I'm talking about This is the effect in iMessage The same effect in Facebook Messenger And again in facebook messenger. I am talking about the little gap of space in between the view that says the number of minutes and the profile image (in the 3rd image). I was wondering how I could achieve the same thing in Swift because I'd like to integrate this into my app. Thank you so much!
You can do this many ways.
One of the way, I am posting.
One View, UIView, that should be Square. Inside that, One UIImageView and One SmallView
Constraints as follows:
OuterView: width & height be 120, top 50, and Center Horizontally
ImageView = { 4,4,4,4 },
SmallView = right and bottom as 0, width and height be 40 [Square]
PlusSignImgVw = { 4,4,4,4 }
Like below:
Coding:
override func viewDidAppear(_ animated: Bool) {
imageVw.layer.cornerRadius = imageVw.frame.size.width / 2
smallSquareView.layer.cornerRadius = smallSquareView.frame.size.width / 2
smallSquareView.clipsToBounds = true
plusSign.layer.cornerRadius = plusSign.frame.size.width / 2
plusSign.clipsToBounds = true
}
Output:
It's a bit tricky, not obvious at first, but not too difficult either.
For the round images, try this:
customView.layer.cornerRadius = customView.bounds.size.width / 2.0
customView.layer.borderWidth = 2.0
customView.layer.borderColor = UIColor.white.cgColor
For the rectangular image with round corners, first line will calculate the .cornerRadius based on height (or you can actually do it for all the cases, and it would also work):
customView.layer.cornerRadius = customView.bounds.size.width / 2.0
Just replace customView with yourCustomViewName and write those 3 lines for each view. That should do the job.

How to center the subviews of UIScrollView

I'm a beginner in creating a custom view. I'm trying to create a custom UIView with a scrollview and buttons that will look like this:
I'm adding a view(view with label of page number) inside of scrollView depending on the the number of pages. Is that how it should be?
Currently it looks like this:
My question is how can I center the subviews of scrollview? and next is what's wrong with this code? Why is that I can only see 1 label inside the view? and the other doesn't show up. How can I scroll to the selected page if the page number is not visible already in the scrollview?
Here's my code:
func addPageNumberViewWithCount(count: Int) {
var pageNumberViewX: CGFloat! = 0
let pageNumberViewDistance: CGFloat! = 10
for i in 1...count {
let pageNumberView = UIView(frame: CGRectMake(pageNumberViewX, 0, 30, 30))
pageNumberView.backgroundColor = UIColor.redColor()
pageNumberView.layer.cornerRadius = pageNumberView.frame.height / 2
pageNumberView.layer.masksToBounds = true
pageNumberView.clipsToBounds = true
// add number label
let label = UILabel(frame: CGRectMake(pageNumberViewX, 0, 30, 30))
label.center = pageNumberView.center
label.text = "\(i)"
label.textAlignment = .Center
pageNumberView.addSubview(label)
// update x for next view
pageNumberViewX = pageNumberView.frame.origin.x + pageNumberView.frame.width + pageNumberViewDistance
// add view inside scrollview
scrollView.addSubview(pageNumberView)
if i == count {
scrollView.contentSize = CGSizeMake(pageNumberViewX + pageNumberView.frame.width, 30)
}
}
}
Part of my answer will go to providing a solution to your question,and another part of my answer will go toward strongly suggesting that this not be the method you use to complete your desired tasks.
At this point, AutoLayout and Interface Builder have come a long way. Where they used to be difficult to use because of their inconsistency and unpredictability, they are now highly predictable and consistent as long as you understand the tools and how to use them.
Apple's suggested method for completing this task (which I mostly stand behind) is creating a .xib file (nib) to lay out the base components of the design, and to load the nib into the view or view controller whenever that design should be used. My question for you: have you tried this, or have you determined for some reason that this would be an unsatisfactory solution to your problem? AutoLayout exists to solve these problems not just in allowing you to achieve your desired solution in this one situation but to achieve it in other situations as well, with varying screen sizes and device types.
Now, if you were to simply ignore all of that and continue on your path, there would be a few good ways to handle your problem. One suggested solution I have:
1) Wrap your pageNumberView in another view. Constrain that view to the size of the scrollView. Doing this gives the scrollView content with which to base its scrollable content size, and gives the inner pageNumberView something to compare itself to.
2) Center the pageNumberView horizontally in its container (the new view that we just created).
Doing this, the page numbers should now center themselves in the container until they reach a size where they exceed the width of the scrollView. At that point, they will then continue to expand, making the area horizontally scrollable.
I can provide code examples of how you would do this, but frankly I would much prefer if you scrapped the idea of doing things this way and instead opted for the AutoLayout method at least, and perhaps even the Interface Builder method. I started out with iOS the same way you did, trying to do everything in code. It really isn't the best way to do things, at least with regard to iOS.
Edit: I've provided an example of how this would look in Interface Builder using UINib. I've populated the view with an example of 5 pages to show what it is like. I will see if I can make a GIF or something similar to show what each of the subviews look like.
For the OP, my suggestion would be this: Use this for reference, and go learn the constraints system. It is extremely unlikely that you will find success with iOS if you do not learn and utilize the constraints system. Coding in X values to a UIView's frame is only going to create a product with poor, inconsistent performance across devices, and will take much, much longer than it would to take the time to learn constraints.
Perhaps you should have a UICollectionView with a cell for each of these buttons. That's a better way of doing this, and you can lay it out again when the screen rotates and it changes width.
Those cells will layout offset to the left. You can solve that this way:
let pageNumberViewTotalWidth = 30 * count + (pageNumberViewDistance * count - 1)
self.collectionView.contentInset.left = (self.collectionView.frame.size.width - pageNumberViewTotalWidth) / 2
The labels aren't showing up because you're setting their frame's x to be the same as the page number view's x. It's frame should be relative to it's superview, in this case pageNumberView.
First Question of yours "how can I center the subviews of scrollview?"
Solution: lets suppose you have in total 50 pages and you want to show 5 pages at a time in the scrollview.
Then make 10 subviews of equal widths where each subview width will be equal to visible portion of the collection view that is
self.view.size.width - 2*(width of toggle button)
Then in each container view add 5 of your pageNumberView placed at equal distance
lets pageNumberViewWidth = container.width/5 - 2*margin
now pageNumberView frame will be (margin,0,pageNumberViewWidth,height)
In this way in each container view your pageNumberViews will be placed equally and it will look as if you have centred them.
Second Question "Why is that I can only see 1 label inside the view?"
Answer : Its because you are setting label frame incorrectly
let label = UILabel(frame: CGRectMake(pageNumberViewX, 0, 30, 30))
Here label is the subview of pageNumberView So you have to set its frame according to its parent's view which is pageNumberView, so change it to
let label = UILabel(frame: CGRectMake(0, 0, 30, 30))
First time it was right because pageNumberViewX is 0 for first iteration after that it become some positive value which makes its frame shifted to right but its parent's width is small so its not visible to you.
Third Question : "How can I scroll to the selected page if the page number is not visible already in the scrollview?"
For this you need to find the frame of your selected page:
you can do that by using the offset that you used to create pageNumberView.
(width of each pageNumberView)*pageNumber = starting point of the required pageNumberView.
let frame : CGRect = CGRectMake(calculated offset above, 0,30, 30)
//where you want to scroll
self.scrollView.scrollRectToVisible(frame, animated:true)
I hope this will help you in solving your problem
Edit for first problem
func addPageNumberViewWithCount(count: Int) {
var containerViewX: CGFloat! = 0
let pageNumberViewDistance: CGFloat! = 10
let pageNumberViewPerSubview = 5
var numberOfSubview = count/pageNumberViewPerSubview
if(count % pageNumberViewPerSubview > 0){
numberOfSubview = numberOfSubview + 1
}
var pagesLeft = count
for i in 1...numberOfSubview {
var pageNumberViewX: CGFloat! = 0
let containerView : UIView = UIView(frame:CGRectMake(containerViewX,0,scrollView.frame.size.width,scrollView.frame.size.height))
if(pagesLeft < pageNumberViewPerSubview){
for k in 1...pagesLeft{
}
}
else{
for j in 1...pageNumberViewPerSubview{
let pageNumberView = UIView(frame: CGRectMake(pageNumberViewX, 0, 30, 30))
pageNumberView.backgroundColor = UIColor.redColor()
pageNumberView.layer.cornerRadius = pageNumberView.frame.height / 2
pageNumberView.layer.masksToBounds = true
pageNumberView.clipsToBounds = true
// add number label
let label = UILabel(frame: CGRectMake(0, 0, 30, 30))
label.text = "\(i)"
label.textAlignment = .Center
pageNumberView.addSubview(label)
// update x for next view
pageNumberViewX = pageNumberView.frame.origin.x + pageNumberView.frame.width + pageNumberViewDistance
containerView.addSubview(pageNumberView)
}
containerViewX = containerViewX + scrollView.frame.size.width
// add view inside scrollview
scrollView.addSubview(containerView)
pagesLeft = pagesLeft - pageNumberViewPerSubview
}
if i == count {
scrollView.contentSize = CGSizeMake(numberOfSubview*scrollView.frame.size.width, 30)
}
}
}

Xcode 6 Interface Builder centre multiple labels in middle of view

I'm writing an iOS app which has multiple labels in one view, like shown:
I would like these labels to be in the vertical centre of the view, with the middle of the collection of labels as the centre of the view.
I need to use auto layout for this, as the top label may be multiple lines, or may only be one depending on input, and will change height depending on this. This, along with the top label being a different size, means that I cannot simple have the middle label in the middle, and the others relative to that.
I'm looking for a solution either in code or IB.
EDIT: To clarify, I am looking to centre the middle of multiple labels, like so:
(The vertical middle might be slightly off)
*The image should read vertical middle
This is an old question of mine, but it maintains a fair number of views, and is quite a common use-case. I do not feel the other answer is a very efficient method to achieve this.
The easiest method to centre a collection of views is to place them within a UIView object which is itself centred.
To use the example above, the three UILabels would be within one UIView, with a 0 constraint between the top and bottom labels and the View. The view itself would then be set to be centred vertically.
I don't think there is a way to do this with Auto Layout, but you can code. I'm assuming you've already figured out the spacing of the labels, so I'll just help you center the whole thing.
var o1 = label1.frame.origin
var o4 = label4.frame.origin
var h4 = label4.frame.height
var w4 = label4.frame.width
var hc4 = o4.y + h4
var wc4 = o4.x + w4
var screen = UIScreen.mainScreen().bounds.size.height
var remainingScreen = (screen - (hc4 - o1.y))/2.0
var screenW = UIScreen.mainScreen().bounds.size.width
var remainingScreenW = (screenW - (wc4 - o1.x))/2.0
var moveH = remainingScreen - o1.y
var moveW = remainingScreenW - o1.x
var frame1 = label1.frame
var frame2 = label2.frame
var frame3 = label3.frame
var frame4 = label4.frame
label1.frame = CGRect(x: frame1.origin.x + moveW, y: frame1.origin.y + moveH, width: frame1.width, height: frame1.height)
label2.frame = CGRect(x: frame2.origin.x + moveW, y: frame2.origin.y + moveH, width: frame2.width, height: frame2.height)
label3.frame = CGRect(x: frame3.origin.x + moveW, y: frame3.origin.y + moveH, width: frame3.width, height: frame3.height)
label4.frame = CGRect(x: frame4.origin.x + moveW, y: frame4.origin.y + moveH, width: frame4.width, height: frame4.height)
This whole thing isn't very self explanatory, but I won't talk about what every line does. The overall idea is it finds the distance between the upper left and lower right corner of all the labels (so UL of label1 and LR of label4 [this only works if you've already set the spacing between labels and the width/height of each label]), then it finds the width/height (W/H) of the screen and subtracts the W/H of the label area, divides by two, giving the space between the top of the screen and the labels. Finally, it finds the distance the entire assembly needs to move by comparing the UL corner with where it should be, and combines the amount to be moved with the original location of all the labels.
Note: This code could be heavily condensed, it is just easier to view and read if it is written like this.

iCarousel - How to shift the focus to the left side

I need to implement iCarousel in a way so that it looks like this:
I have done all the modifications at my end to make it look like this but now the problem is that iCarousel works with the center image in the focus. Can I make it so that if there are only two images, they don't appear in the center but rather on the left? Think about it like the "left indented" content.
How do I do this?
iCarousal provide a property to sift focus left or right by set the width offset.
For right side use this code for swift 2.3 -
let widthOffset: Float = -120.0
self.customCarousel.viewpointOffset = CGSize(width: CGFloat(widthOffset), height: CGFloat(0))
This should be the property in iCarousel you are looking for viewpointOffset
Example...
// Modifiy widthOffset so it works well in your case
float widthOffset = 100.0;
[_yourCarousel setViewpointOffset:CGSizeMake(widthOffset, 0)];
The viewpointOffset property doesn't really work that way. It will let you align to one edge, but then when you scroll to the end you'll have the same problem.
iCarousel wasn't designed to do this. I suggest you switch to SwipeView instead (http://github.com/nicklockwood/SwipeView) which has the same delegate/datasource interface, but has an alignment property that you can use to set edge alignment, like this:
swipeView.alignment = SwipeViewAlignmentEdge;
Visit https://github.com/nicklockwood/iCarousel/issues/142
it may help.
nicklockwood (author) answer:
You could use the delegate and create a custom transform that offsets all of your views by a negative amount. Something like this:
- (CATransform3D)carousel:(iCarousel *)carousel itemTransformForOffset:(CGFloat)offset baseTransform:(CATransform3D)transform
{
float OFFSET_WIDTH = ...; // set this to about half the width of your view
return CATransform3DMakeTranslation(offset * itemWidth - OFFSET_WIDTH, 0, 0);
}
The only problem would be that when you reach the rightmost end of the
carousel there would be a gap, but you could use placeholder views to
fill the gap up.
I tripped over the same problem. After simple math I've found a more accurate answer. I've put this code in my viewDidAppear() function, because when I put it in viewDidLoad() the view.frame.width and view.frame.height took the original width of my storyboard, which didn't fit to bigger devices.
My use case was the following. My iCarousel items are simple squares. That means, I have for example a height of 3 and a width of 3. But the width of my iCarousel view is 5. In sum I have 5-3=2 space, 1 left and 1 right (because we know it's default is centered). So last step is to divide with 2 to get the width on one site = 1. With this knowledge we just have to set the viewPointOffset to 1 (in this case).
Final formular: let widthOffset = (view.frame.width - view.frame.height) / 2
Example in my code:
let widthOffset: Float = Float((mDetailCarousel.frame.width - mDetailCarousel.frame.height) / 2 )
mDetailCarousel.viewpointOffset = CGSize(width: CGFloat(widthOffset), height: CGFloat(0))

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