How to put UISlider vertical? - objective-c

I want to put UISlider in vertically. I have no idea about this, so please help me for this.

You have to do this programaticaly. Assuming your UISlider is bound to a variable called slider, add this code in your viewDidLoad method in ViewController.m:
- (void)viewDidLoad {
[super viewDidLoad];
CGAffineTransform trans = CGAffineTransformMakeRotation(M_PI * 0.5);
slider.transform = trans;
}
Let me know if you need any more help on this..

As of Xcode 4.2, you can sort of do the same in Interface Builder.
Create a slider
Show the "Identity Inspector"
Add a "User Defined Runtime Attribute"
Set the key path to "layer.transform.rotation.z", the type as "String" ("Number" won't allow floating point values) (possible since Xcode 5) and the value to "-1.570795" (-π/2).
Unfortunately, it will still appear as horizontal in Interface Builder.
But you can position the center and don't need to create a custom class, so it might be useful enough in some cases. The effect is the same as ravinsp's code.

Swift 3:
slider.transform = slider.transform.rotated(by: CGFloat(0.5 * Float.pi))
// Use 1.5 to invert the shadow of slider if you want

In case you work with auto layouts:
In your viewDidLoad, try:
UIView *superView = self.sizeSlider.superview;
[self.sizeSlider removeFromSuperview];
[self.sizeSlider removeConstraints:self.view.constraints];
self.sizeSlider.translatesAutoresizingMaskIntoConstraints = YES;
self.sizeSlider.transform = CGAffineTransformMakeRotation(M_PI_2);
[superView addSubview:self.sizeSlider];
It does not work with constraints, so the trick is to remove the constraints for your uislider.
You might have to resize it manually by setting its frame property.

Using an IBOutlet and setter observers.
If you want the max to be at the bottom, divide pi by positive 2
#IBOutlet weak var slider: UISlider! {
didSet {
slider.transform = CGAffineTransform(rotationAngle: .pi / -2)
}
}

Related

How to make UICollectionheader transparent while scrolling up?

Please help me to make the UICollectionview header transparent while we scroll the collection view up. I have used UICollectionReusableView and set it background as clear color, but no use. WHILE MOVING UP THE HEADER ( SHOWN IN BLACK COLOR) SHOULD BECOME TRANSPARENT.... THAT IS THE ORANGE BACKGROUND SHOULD BE SLIGHTLY VISIBLE....
Not enough info, but I'll try to answer
First, you should keep pointer to your header view constantly
#property UICollectionReusableView *collectionHeaderView;
Create it once in viewDidLoad and than use it as a header view (whatever that means) in your collection view.
Next, to change collor on dragging up you'll need delegate method.
UICollectionViewDelegate conforms to UIScrollViewDelegate, so you can use its method
- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView
{
CGPoint translation = [scrollView.panGestureRecognizer translationInView:scrollView.superview];
if(translation.y > 0)
{
//dragging down
collectionHeaderView.backgroundColor = <#Whatever you need#>;
} else
{
// dragging up
collectionHeaderView.backgroundColor = [UIColor clearColor];
}
}
Special thanks to #mvielbut for answer
Update
According to comments to mvielbut's answer, this method is not always reliable, so you can use another approach (you'll need to check offset.y instead).

Vertical UISlider in iOS with autolayout

As per my iPad app requirement, i've to show the UISlider vertically.
I'm using iOS7 compiler and deployment target is iOS6.
In the story board I added horizontal UISlider of width 600 pixels. I created IBOutlet in my view controller. I didn't set any auto layout constraints. I'm using the below code to rotate and make it vertical.
self.slider.transform = CGAffineTransformMakeRotation(M_PI_2);
After and before rotation I'm printing the frame size of the slider which is correct. But the slider is not looking proper. Its just showing only knob in the center. How can I rotate the UISlider?
I got a vertical slider working with iOS 8 and Xcode 6 with only 3 constraints in the storyboard and one line of code. Here's a cropped screencap of the interface:
There are 3 constraints between the vertical slider and the UIImageView next to it:
vSlider.Center Y = Image View.Center Y
vSlider.Width = Image View.Height
vSlider.Center X = Image View.Trailing + 16
And of course the one line of code is:
self.vSlider.transform = CGAffineTransform(rotationAngle: CGFloat(Double.pi / 2))
It's easy to set up these constraints in the storyboard in Xcode 6, but I think it should be simple to write these constraints in code to support iOS 7 or 6.
I got it to work this way:
In viewDidLoad: I added
[self.slider removeConstraints:self.slider.constraints];
[self.slider setTranslatesAutoresizingMaskIntoConstraints:YES];
so that it's called before rotating the slider with
self.slider.transform=CGAffineTransformRotate(self.slider.transform,270.0/180*M_PI);
and there is no need to remove and re-add it to superview.
This is an old topic, but here is a Swift solution with autolayout constraints in storyboard and nothing else.
1/ You need to add rotation to the IBOutlet:
#IBOutlet weak var mySlider: UISlider! {
didSet {
mySlider.transform = CGAffineTransform(rotationAngle: -CGFloat.pi/2)
} // didSet
} // IBOutlet
2/ Define in storyboard the constraints, keeping in mind that the Slider will be rotated around its center.
For instance if you want to locate mySlider on the left side of myView, you need three constraints.
myView.Leading = mySlider.CenterX - 20
mySlider.width = myView.Height (with a multiplier of 0.8 for instance)
mySlider.CenterY = myView.CenterY
mySlider will of course appear horizontal in storyboard, but will have the correct sizing, and the center will be correctly positioned.
Uncheck Auto-Layout on your ViewController, there is no other option under the SDK 7.0 to make it work vertically :(
There are so many possible solutions around about putting UISlider vertical. Here is my summary for iOS7 in XCode5 with autoLayout enabled(defaultly in storyboard):
in viewDidLoad add method
self.slider.transform = CGAffineTransformMakeRotation(M_PI_2);
define your autoLayout constraints about slider explicitly in storyboard as whatever you like
In your viewDidLoad, try:
UIView *superView = self.sizeSlider.superview;
[self.sizeSlider removeFromSuperview];
[self.sizeSlider removeConstraints:self.view.constraints];
self.sizeSlider.translatesAutoresizingMaskIntoConstraints = YES;
self.sizeSlider.transform = CGAffineTransformMakeRotation(M_PI_2);
[superView addSubview:self.sizeSlider];
It does not work with constraints, so the trick is to remove the constraints for your uislider.
You might have to resize it manually by setting its frame property.
You can't use storyboard to build up a UISlider.
Build up UISlider by coding.
slider = [[UISlider alloc] initWithFrame:CGRectMake(640, 150, 600, 400)];
[slider.layer setAnchorPoint:CGPointMake(0.0f, 0.0f)];
slider.transform = CGAffineTransformMakeRotation(M_PI/2);
[self.view addSubview:slider];
Try this :-
self.slider.transform=CGAffineTransformRotate(slideToUnlock.transform,-90.0/180*M_PI);
Try below code to Rotate the UISlider in Vertical Position..
//To rotate the slider in Vertical Position
CGAffineTransform sliderRotation = CGAffineTransformIdentity;
sliderRotation = CGAffineTransformRotate(sliderRotation, -(M_PI / 2));
sliderBrightness.transform=sliderRotation;
For me a two-step process worked best (incorporating some of the previous solutions)
Autolayout step)
I added a vertical view in IB and used autolayout to link it to neighboring views. Then I added a slider in the view and simply hooked it up to the center of the view. Then hooked up the width of the slider to the height of the view. Finally control-dragged the slider outlet to my ViewController code (as slider)
Code step)
Then simply added the to my viewWillAppear (swift-code):
let trans = CGAffineTransformMakeRotation(CGFloat(M_PI_2));
slider.transform = trans;

Added whitespace in UIWebview - removing UIWebView whitespace in iOS7 & iOS8

Im loading local html files, since iOS7 there is added white space on top in the UIWebView.(I cant post an image as i do not have enough points.)
image can be seen here- snap shot from iPhone simulator, uiwebview surrounded by black frame, the html content is grey, but there is white added above it
I have tried to adjust the zoom using
[webView stringByEvaluatingJavaScriptFromString:#"document. body.style.zoom = 5.0;"];
webView.scalesPageToFit = NO;
credit to: Srikar Appal
I also set tried to remove white spacing:
NSString *padding = #"document.body.style.margin='0';document.body.style.padding = '0'";
[webView stringByEvaluatingJavaScriptFromString:padding];
credit to: thenextmillionaire
still no luck. In the desktop chrome browser there is no whitespace. The html files are Google Swiffy files - containing html and JSON.
edit: updated Image
Try self.automaticallyAdjustsScrollViewInsets = NO; in ViewDidLoad.
ios 7 add 64px automatically for scroll view. (status bar and nav bar)
This problem only affects the UIWebView if it is the first subview of the parent view. One alternative way to work around this problem is to add another non-visible empty view to the parent view as the first view. In Interface Builder add a zero size subview and use the Editor->Arrange->Send to Back menu command.
If you're not using Interface Builder, but instead are subclassing the UIWebView, then it can be done by creating a UIView instance variable called scrollFixView and overriding the following methods:
- (void)didMoveToSuperview
{
[super didMoveToSuperview];
if ([self superview].subviews.firstObject == self) {
_scrollFixView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 0, 0)];
_scrollFixView.hidden = YES;
[[self superview] insertSubview:_scrollFixView belowSubview:self];
}
}
- (void)removeFromSuperview
{
if (_scrollFixView) {
[_scrollFixView removeFromSuperview];
_scrollFixView = nil;
}
[super removeFromSuperview];
}
I had the same problem so I tried a few things:-)
This worked for me, but correct me please if there is a better way.
-(void)webViewDidFinishLoad:(UIWebView *)webView
{
if(self.navigationController.navigationBar.translucent == YES)
{
_webView.scrollView.contentOffset = CGPointMake(_webView.frame.origin.x, _webView.frame.origin.y - 54);
}
}
So basically you need to :
1) Add the UIWebView delegate method - webViewDidFinishLoad:
2) Then I setup an if statement to check if the translucent option is active.
The last one you only need to do of course if you give the user the option within your app.
The number after the _webView.frame.origin.y is just for my app. It may differ for you.
I solved this problem by simply setting a constraint on the WebView, setting the top space between it and the View top to 0, causing the NavBar to overlap the whitespace.
One alternative to Jeff Kranenburg's method is to subclass and override the UIWebView subclasses' UIScrollViewDelegate method scrollViewDidScroll:. This is only appropriate if scrolling is turned off for your subclass.
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
if ([[self superclass] instancesRespondToSelector:_cmd]) {
[super scrollViewDidScroll:scrollView];
}
[self fixUpScrollViewContentOffset];
}
- (void)fixUpScrollViewContentOffset
{
if (!CGPointEqualToPoint(self.scrollView.contentOffset, CGPointZero)) {
self.scrollView.contentOffset = CGPointZero;
}
}
I already got it .
here my logic code, When the application open the website you must get the size of your webview then set it on height
here my code
ViewGroup.MarginLayoutParams p = (ViewGroup.MarginLayoutParams) webpage.getLayoutParams();
p.height = webpage.getHeight();
// check if how long you need to set your height for webpage then set it :)
Log.e(" webpage.getHeight()", String.valueOf(webpage.getHeight()));
webpage.setLayoutParams(p);
Hope you will take my code and my answer to :) works on any devices even tabs too :)

UIScrollView contentSize not working

I put a UIScrollView in my nib's view, and linked it to a an IBOutlet property.
Now, when I do this in my viewDidLoad method, it seems to have no effect on the contentSize:
self.sv.backgroundColor = [UIColor yellowColor]; // this works
CGSize size = CGSizeMake(1000.0, 1000.0);
[self.sv setContentSize:size]; // this does not
It behaves as if the contentSize was the same as the frame. What's going on?
This started working when I turned off AutoLayout. Why?
I had the same problem. Auto Layout for UIScrollView is messed up.
Work around: Put everything in the UIScrollView into another UIView, and put that UIView as the only child of the UIScrollView. Then you can use Auto Layout.
If things near the end is messed up (the end of whichever direction your UIScrollView scrolls), change the constraint at the end to have the lowest possible priority.
I tried viewWillLayoutSubviews to update scrollView's contentSize, it worked for me.
- (void)viewDidLayoutSubviews
{
[self.bgScrollView setContentSize:CGSizeMake(320, self.view.frame.size.height* 1.5)];
}
Apple Doc
-(void)viewDidLayoutSubviews
Called to notify the view controller that its view has just laid out its subviews.
Discussion
When the bounds change for a view controller’s view, the view adjusts the positions of its subviews and then the system calls this method. However, this method being called does not indicate that the individual layouts of the view’s subviews have been adjusted. Each subview is responsible for adjusting its own layout.
Your view controller can override this method to make changes after the view lays out its subviews. The default implementation of this method does nothing.
The easiest/cleanest way is to set contentSize at viewDidAppear so you negate the effects of autolayout. This doesn't involve adding random views. However relying on load order for an implementation to work may not be the best idea.
Use this code. ScrollView setContentSize should be called async in main thread.
Swift:
override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
DispatchQueue.main.async {
var contentRect = CGRect.zero
for view in self.scrollView.subviews {
contentRect = contentRect.union(view.frame)
}
self.scrollView.contentSize = contentRect.size
}
}
Objective C:
- (void)viewDidLayoutSubviews {
[super viewDidLayoutSubviews];
dispatch_async(dispatch_get_main_queue(), ^ {
CGRect contentRect = CGRectZero;
for(UIView *view in scrollView.subviews)
contentRect = CGRectUnion(contentRect,view.frame);
scrollView.contentSize = contentRect.size;
});
}
There are two problems here. (1) viewDidLoad is too soon; you have to wait until after layout has taken place. (2) If you want to use autolayout with a scrollview that comes from a nib, then either you must use constraints to completely describe the size of the contentSize (and then you don't set the contentSize in code at all), or, if you want to set it in code, you must prevent the constraints on the scrollview's subviews from dictating the contentSize. It sounds like you would like to do the latter. To do so, you need a UIView that acts as the sole top-level subview of the scrollview, and in code you must set it to not use autolayout, enabling its autoresizingMask and removing its other external constraints. I show an example of how to do that, here:
https://github.com/mattneub/Programming-iOS-Book-Examples/blob/master/ch20p573scrollViewAutoLayout/ch20p573scrollViewAutoLayout/ViewController.m
But notice also the next example, which shows how to use constraints completely, instead of contentSize.
A SUPER easy way to use AutoLayout with UIScrollViews inside Interface Builder:
Step 1: Create a UIScrollView
Step 2: Create a UIView that is a child of your scroll view like so:
-UIScrollView
---UIView
-----Your other content
(We'll call this one contentView).
Step 3: In the size inspector, give this view a height and width (say, 320x700).
Step 4 (using AutoLayout): Create unambiguous constraints from your contentView to its superview (the UIScrollView): connect the 4 edges (top, leading, trailing, bottom), then give it a defined width and height that you want it to scroll too.
For example: If your scroll view spans the entire screen, you could give your content view a width of [device width] and a height of 600; it will then set the content size of the UIScrollView to match.
OR:
Step 4 (not using AutoLayout): Connect both of these new controls to your view controller using IB (ctrl+drag from each control to your view controller's .h #implementation). Let's assume each is called scrollView and contentView, respectively. It should look like this:
#interface YourViewController : UIViewController
#property (strong, nonatomic) IBOutlet UIScrollView *scrollView;
#property (strong, nonatomic) IBOutlet UIView *contentView;
#end
Step 5 (not using AutoLayout): In the view controller's .h file add (actually, override) the following method:
-(void)viewDidLayoutSubviews
{
[super viewDidLayoutSubviews];
self.scrollView.contentSize = self.contentView.frame.size;
}
You can use this lines of code into your *.m file's
- (void)viewDidLoad{
[scroll setContentSize:CGSizeMake(320, 800)] ;
[scroll setScrollEnabled:TRUE];
[scroll setShowsVerticalScrollIndicator:NO];
[scroll setShowsHorizontalScrollIndicator:YES];
}
for this you need to take an IBOutlet property of UIScrollView into your *.h file this way:
IBOutlet UIScrollView *scroll;
And connect this from Storyboard.
Or,
You can use this method into your *.m file:
-(void)viewDidLayoutSubviews
{
[scroll setContentSize:CGSizeMake(320, self.view.frame.size.height* 1.5)];
// this will pick height automatically from device's height and multiply it with 1.5
}
This both solution works for me in xcode-5, xcode-6, xcode-6.1, xcode-6.2
Setting the contentSize in viewDidAppear is critical.
But I also had a variation of what worked in the 3.5 inch screen, and the 4 inch screen. The 4 inch screen worked, the older one does not. Both iOS 7. Bizarre is an understatement!
I could never get auto layout based on constraints to work. Since my view was already a subclass UIScrollView I solved it by overriding setContentView: and ignoring auto layouts zero height setContentSize: message.
#interface MyView : UIScrollView {}
#end
#implementation MyView
- (void)setContentSize:(CGSize)aSize {
if (aSize.height > 0)
[super setContentSize:aSize];
}
#end
I used to do set up the uiscrollview programmatically UNTIL I watched the following wonderful tutorial, step by step how to get uiscrollview and uiview to work: https://www.youtube.com/watch?v=PgeNPRBrB18
After watching the video you will start liking Interface Builder I am sure.
Vote up
Still not scrolling when dynamic height of labels exceeds view height.
I did what yuf's answer marked as correct above said to do (I added a content view to my scrollview and set the constraints leading, trailing, top bottom, and equal widths from the content view to the scroll view.) but still my view was not scrolling when the internal controls height exceeded the height of the scrollview.
Inside my content view I have an image and 3 labels below it. Each label adjusts their own height dependant on how much text is in them (they are set to word-wrap and numberoflines = 0 to achieve this).
The problem I had was my content view's height was not adjusting with the dynamic height of the labels when they exceeded the height of the scroll view/main view.
To fix this I worded out I needed to set the Bottom Space to Container constraint between my bottom label and the contentview and gave it a value of 40 (chosen arbitrarily to give it a nice margin at the bottom). This now means that my contentview adjusts its height so that there is a space between the bottom of the last label and itself and it scrolls perfectly!
Yay!
Try this out...
add all constraints like you do for UIView (See screenShot of my ViewControler in Storyboard)
Now trick begins. select your last object and select its bottom constraint. (See above screenShot, Instagram button's Bottom Constraint(Yellow line)) and Change the Constant in Size Inspector like in bellow screenshot.
i require Constant=8 but you can change as per your requirements.
this Constant is the Space between That Orange Button's Bottom and the scrollView.
EDIT
Make Sure about your view's hierarchy .
0) ViewController.view (optional)
1) UIScrollView
2) UIView (Rename as "contentView")
3) UIView (this view is your content that will make scrollView scroll)
I finally worked out my own solution to this problem because in my case I couldn't use the view controller's life cycle. Create your own scroll view subclass and use it instead of UIScrollView. This even worked for a scroll view inside a collection view cell.
class MyScrollView:UIScrollView {
var myContentSize:CGSize = CGSize.zero // you must set this yourself
override func layoutSubviews() {
super.layoutSubviews()
contentSize = myContentSize
}
}
My MyScrollView was defined in the nib with a tag of 90. If so this is a good way to set content size in the code in the parent view.
let scrollView = viewWithTag(90) as! MyScrollView
scrollView.myContentSize = ...
If you are using AutoLayout a really easy way to set the contentSize of a UIScrollView is just to add something like this:
CGFloat contentWidth = YOUR_CONTENT_WIDTH;
NSLayoutConstraint *constraintWidth =
[NSLayoutConstraint constraintWithItem:self.scrollView
attribute:NSLayoutAttributeTrailing
relatedBy:NSLayoutRelationEqual
toItem:self.scrollView
attribute:NSLayoutAttributeLeading
multiplier:1
constant:contentWidth];
[self.scrollView addConstraint:constraintWidth];
I got Autolayout to work for paginated scroll views whose pages occupy the full-width of the screen. The pages automatically resize according to the scroll view's size. I haven't tested this for lesser-width scroll views but do comment away if it works--I beleieve it should. Targeted for iOS 9, wrote code in Swift 2, used a mix of IB's and custom code in awakeFromNib.
Steps:
Define a full-screen scroll view.
Inside the scroll view, add a UIView (I called mine contentView) whose top, trailing, bottom, and leading edges to the scroll view are all zero; the height is equal to the scroll view's; but the width is the scroll view's width times the number of pages. If you're doing this visually, you will see your content view extend beyond your scroll view in Inteface Builder.
For every "page" inside the contentView, add Autolayout rules to put them side-by-side each other, but most importantly, give them each a constraint so that their widths are equal to the scroll view's, not the content view's.
Sample code below. embedChildViewController is just my convenience method for adding child VCs--do look at setupLayoutRulesForPages. I have exactly two pages so the function is too simple, but you can expand it to your needs.
In my view controller:
override func loadView() {
self.view = self.customView
}
override func viewDidLoad() {
super.viewDidLoad()
self.embedChildViewController(self.addExpenseVC, toView: self.customView.contentView, fillSuperview: false)
self.embedChildViewController(self.addCategoryVC, toView: self.customView.contentView, fillSuperview: false)
self.customView.setupLayoutRulesForPages(self.addExpenseVC.view, secondPage: self.addCategoryVC.view)
}
My custom view:
class __AMVCView: UIView {
#IBOutlet weak var scrollView: UIScrollView!
#IBOutlet weak var contentView: UIView!
#IBOutlet weak var pageControl: UIPageControl!
override func awakeFromNib() {
super.awakeFromNib()
self.scrollView.pagingEnabled = true
self.scrollView.bounces = true
self.scrollView.showsHorizontalScrollIndicator = false
self.scrollView.showsVerticalScrollIndicator = false
self.pageControl.numberOfPages = 2
self.contentView.backgroundColor = UIColor.blueColor()
self.scrollView.backgroundColor = UIColor.clearColor()
self.backgroundColor = UIColor.blackColor()
}
func setupLayoutRulesForPages(firstPage: UIView, secondPage: UIView) {
guard self.contentView.subviews.contains(firstPage) && self.contentView.subviews.contains(secondPage)
else {
return
}
let rules = [
"H:|-0-[firstPage]-0-[secondPage]-0-|",
"V:|-0-[firstPage]-0-|",
"V:|-0-[secondPage]-0-|"
]
let views = [
"firstPage" : firstPage,
"secondPage" : secondPage
]
let constraints = NSLayoutConstraint.constraintsWithVisualFormatArray(rules, metrics: nil, views: views)
UIView.disableAutoresizingMasksInViews(firstPage, secondPage)
self.addConstraints(constraints)
// Add the width Autolayout rules to the pages.
let widthConstraint = NSLayoutConstraint(item: firstPage, attribute: .Width, relatedBy: .Equal, toItem: self.scrollView, attribute: .Width, multiplier: 1, constant: 0)
self.addConstraint(widthConstraint)
}
}

IOS: change UIImageView with tag value

I have 20 UIImageView and i want change their image; but I don't want to create 20 IBOutlet, and I want to use tag value to change the image; I set the tag value in interface builder and after? If I want to change image at Imageview number 15? How can I do?
UIImageView *imageView=(UIImageView *)[self.view viewWithTag:*givetag*];
[imageView setImage:[UIImage imageNamed:#"nameof yourimage"]];
If you use tags you can identify your tagged view (UIImageView is a subclass of UIView, which has the tag attribute) like this:
- (UIView *)viewWithTag:(NSInteger)tag
So if you call this method on your superview (which all the UIImageViews reside in), you should do it like this:
UIImageView *myImageView = (UIImageView *)[myAwesomeSuperview viewWithTag:15];
(Documentation I found using Google).
P.S: if you think it is too much work to add 20 IBOutlets, I recommend you create the UIImageViews programmatically as well. This way you will not need a xib file at all, write a small piece of code and have better maintenance with less effort.
SWIFT, April 2015:
func createUIImageViews()
{
for i in 0...99
{
var imageView:UIImageView = UIImageView(frame: CGRectMake(CGFloat(0), CGFloat(0), CGFloat(100), CGFloat(100)))
imageView.userInteractionEnabled = true
imageView.tag = i
imageView.addGestureRecognizer(UITapGestureRecognizer(target: self, action: "onImageViewTap:"))
self.view.addSubview(imageView)
}
}
func onImageViewTap(sender:UITapGestureRecognizer)
{
println("TAP: \(sender.view!.tag)")
}