Looping through UIImageViews in UIView - Swift - ios

I've been trying to do something in Swift that is very similar to the below code sample (Objective C). Is anyone able to provide a Swift implementation of the function shown below or something similar?
- (UIImageView *) getSectorByValue:(int)value {
UIImageView *res;
NSArray *views = [container subviews];
for (UIImageView *im in views) {
if (im.tag == value)
res = im;
}
return res;
}

This is a similar implementation in Swift:
func getSectorByValue(value: Int) -> UIImageView? {
for subView in container.subviews {
if subView.tag == value {
return subView as? UIImageView
}
}
return nil
}

Something like this should work.
func getSectorByValue(value: Int) -> UIImageView? {
let views = container.subviews()
if let i = views.indexOf({$0.tag == value}) {
return views[i] as? UIImageView
}
return nil
}

Looping though the subviews manually is needlessly complex.
There is a UIView method viewWithTag that fetches the desired view with 1 line of code:
func getSectorByValue(value: Int) -> UIImageView?
{
return container.viewWithTag(value) as? UIImageView
}

Related

iOS 13 Custom UISearchBar _searchField crash

with the new iOS 13, i got a crash trying to change the UISearchBar textField properties using valueForKey:#"_searchField"
Now seems that Apple has changed something.
I've created a subclass of UIView with the following custom method and now it seems to work!
- (UIView *)findSubview:(NSString *)name resursion:(BOOL)resursion
{
Class class = NSClassFromString(name);
for (UIView *subview in self.subviews) {
if ([subview isKindOfClass:class]) {
return subview;
}
}
if (resursion) {
for (UIView *subview in self.subviews) {
UIView *tempView = [subview findSubview:name resursion:resursion];
if (tempView) {
return tempView;
}
}
}
return nil;
}
You can simply call this method this way to change UITextField properties:
UITextField *textField = (UITextField*)[self findSubview:#"UITextField" resursion:YES];
Obviously this is an Objective-c snippet and if anyone knows how to write the same code in swift can add it to the answers.
Happy coding!
I'm not sure if it would help, but UISearchBar has a new searchTextField property allowing you to access its UISearchTextField and, in turn, its UITextField:
let searchBar = UISearchBar()
var searchField : UITextField
if #available(iOS 13.0, *) {
searchField = searchBar.searchTextField
} else {
searchField = //Your original method
}
You can do it by using below extension
extension UISearchBar {
func getAllSubview<T : UIView>(type : T.Type) -> [T]{
var all = [T]()
func getSubview(view: UIView) {
if let aView = view as? T{
all.append(aView)
}
guard view.subviews.count>0 else { return }
view.subviews.forEach{ getSubview(view: $0) }
}
getSubview(view: self)
return all
}
}
Use like:
self.searchBar.getAllSubview(type: UITextField.self).first
Output:
<UISearchBarTextField: 0x7fc68d850a00; frame = (0 0; 0 0); text = ''; opaque = NO; layer = <CALayer: 0x600000d29aa0>>
My project is in Objective c and i need to support XCode10 as well so, After two days of headache below line saved my day :
txfSearchField = [_searchBar valueForKey:#"searchField"];
Just need to Remove _ from the old code!!!
In Swift also you can use the same.
Hope it will help someone!

Trying to loop through UIView and all subviews to get the first responder, not working

I am trying to find the current focused First Responder by looping through the main UIView and all of it's SubViews, and all of it's SubViews through recursion, but I am coming up with nil.
extension UIView {
func getCurrentFirstResponder() -> AnyObject? {
if self.isFirstResponder() {
return self
}
for subView: UIView in self.subviews as [UIView] {
if subView.isFirstResponder() {
return subView
}
else {
subView.getCurrentFirstResponder()
}
}
return nil
}
}
let focusedView = self.view.getCurrentFirstResponder() as? UIView
Does this look correct? Why am I getting a nil view when I use this?
You code doesn't return anything in case the recursive call to subView.getCurrentFirstResponder() actually finds a first responder.
Try this:
for subView: UIView in self.subviews as [UIView] {
if subView.isFirstResponder() {
return subView
}
else {
if let sub = subView.getCurrentFirstResponder() {
return sub;
}
}
}
return nil

Find UILabel in UIView in Swift

I'm trying to find my UILabels in my superview of my UIViewControllers.
This is my code:
func watch(startTime:String, endTime:String) {
if superview == nil {println("NightWatcher: No viewcontroller specified");return}
listSubviewsOfView(self.superview!)
}
func listSubviewsOfView(view: UIView) {
var subviews = view.subviews
if (subviews.count == 0) { return }
view.backgroundColor = UIColor.blackColor()
for subview in subviews {
if subview.isKindOfClass(UILabel) {
// do something with label..
}
self.listSubviewsOfView(subview as UIView)
}
}
This is how it is recommended to in Objective-C, but in Swift I get nothing but UIViews and CALayer. I definitely have UILabels in the view that is supplied to this method. What am I missing?
The call in my UIViewController:
NightWatcher(view: self.view).watch("21:00", endTime: "08:30") // still working on
Here's a version that will return an Array of all the UILabel views in whatever view you pass in:
func getLabelsInView(view: UIView) -> [UILabel] {
var results = [UILabel]()
for subview in view.subviews as [UIView] {
if let labelView = subview as? UILabel {
results += [labelView]
} else {
results += getLabelsInView(view: subview)
}
}
return results
}
Then you can iterate over them to do whatever you'd like:
override func viewDidLoad() {
super.viewDidLoad()
let labels = getLabelsInView(self.view)
for label in labels {
println(label.text)
}
}
Using functional programming concepts you can achieve this much easier.
let labels = self.view.subviews.flatMap { $0 as? UILabel }
for label in labels {
//Do something with label
}
Swift 4
Adepting mKane's answer you can use this code:
let labels = self.view.subviews.compactMap { $0 as? UILabel }
for label in labels {
// do whatever
}
You could set a tag to your UILabel in the Storyboard or programmatically using:
myLabel.tag = 1234
Then, to find it use:
let myLabel = view.viewWithTag(1234)

UIBarButtonItem: How can I find its frame?

I have a button in a toolbar. How can I grab its frame? Do UIBarButtonItems not have a frame property?
Try this one;
UIBarButtonItem *item = ... ;
UIView *view = [item valueForKey:#"view"];
CGFloat width;
if(view){
width=[view frame].size.width;
}
else{
width=(CGFloat)0.0 ;
}
This way works best for me:
UIView *targetView = (UIView *)[yourBarButton performSelector:#selector(view)];
CGRect rect = targetView.frame;
With Swift, if you needs to often work with bar button items, you should implement an extension like this:
extension UIBarButtonItem {
var frame: CGRect? {
guard let view = self.value(forKey: "view") as? UIView else {
return nil
}
return view.frame
}
}
Then in your code you can access easily:
if let frame = self.navigationItem.rightBarButtonItems?.first?.frame {
// do whatever with frame
}
Oof, lots of rough answers in this thread. Here's the right way to do it:
import UIKit
class ViewController: UIViewController {
let customButton = UIButton(type: .system)
override func viewDidLoad() {
super.viewDidLoad()
customButton.setImage(UIImage(named: "myImage"), for: .normal)
self.navigationItem.rightBarButtonItem = UIBarButtonItem(customView: customButton)
}
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
print(self.customButton.convert(self.customButton.frame, to: nil))
}
}
Thanks to Anoop Vaidya for the suggested answer. An alternative could be (providing you know the position of the button in the toolbar)
UIView *view= (UIView *)[self.toolbar.subviews objectAtIndex:0]; // 0 for the first item
CGRect viewframe = view.frame;
Here's what I'm using in iOS 11 & Swift 4. It could be a little cleaner without the optional but I'm playing it safe:
extension UIBarButtonItem {
var view: UIView? {
return perform(#selector(getter: UIViewController.view)).takeRetainedValue() as? UIView
}
}
And usage:
if let barButtonFrame = myBarButtonItem.view?.frame {
// etc...
}
Edit: I don't recommend using this anymore. I ended up changing my implementation to use UIBarButtonItems with custom views, like Dan's answer
-(CGRect) getBarItemRc :(UIBarButtonItem *)item{
UIView *view = [item valueForKey:#"view"];
return [view frame];
}
You can create a UIBarButtonItem with a custom view, which is a UIButton, then you can do whatever you want. :]
in Swift 4.2 and inspired with luca
extension UIBarButtonItem {
var frame:CGRect?{
return (value(forKey: "view") as? UIView)?.frame
}
}
guard let frame = self.navigationItem.rightBarButtonItems?.first?.frame else{ return }
You can roughly calculate it by using properties like layoutMargins and frame on the navigationBar, combined with icon size guides from Human Interface Guidelines and take into count the current device orientation:
- (CGRect)rightBarButtonFrame {
CGFloat imageWidth = 28.0;
CGFloat imageHeight = UIDevice.currentDevice.orientation == UIDeviceOrientationLandscapeLeft || UIDevice.currentDevice.orientation == UIDeviceOrientationLandscapeRight ? 18.0 : 28.0;
UIEdgeInsets navigationBarLayoutMargins = self.navigationController.navigationBar.layoutMargins;
CGRect navigationBarFrame = self.navigationController.navigationBar.frame;
return CGRectMake(navigationBarFrame.size.width-(navigationBarLayoutMargins.right + imageWidth), navigationBarFrame.origin.y + navigationBarLayoutMargins.top, imageWidth, imageHeight);
}
Try this implementation:
#implementation UIBarButtonItem(Extras)
- (CGRect)frameInView:(UIView *)v {
UIView *theView = self.customView;
if (!theView.superview && [self respondsToSelector:#selector(view)]) {
theView = [self performSelector:#selector(view)];
}
UIView *parentView = theView.superview;
NSArray *subviews = parentView.subviews;
NSUInteger indexOfView = [subviews indexOfObject:theView];
NSUInteger subviewCount = subviews.count;
if (subviewCount > 0 && indexOfView != NSNotFound) {
UIView *button = [parentView.subviews objectAtIndex:indexOfView];
return [button convertRect:button.bounds toView:v];
} else {
return CGRectZero;
}
}
#end
You should do a loop over the subviews and check their type or their contents for identifying.
It is not safe to access view by kvo and you cannot be sure about the index.
Check out this answer: How to apply borders and corner radius to UIBarButtonItem? which explains how to loop over subviews to find the frame of a button.
I used a view on the bar button item with a tag on the view:
for view in bottomToolbar.subviews {
if let stackView = view.subviews.filter({$0 is UIStackView}).first {
//target view has tag = 88
if let targetView = stackView.subviews.filter({$0.viewWithTag(88) != nil}).first {
//do something with target view
}
}
}
Swift 4 up The current best way to do it is to access its frame from :
self.navigationItem.rightBarButtonItems by
let customView = navigationItem.rightBarButtonItems?.first?.customView // access the first added customView
Accessing this way is safer than accessing private api.
check out the answer in this :
After Add a CustomView to navigationItem, CustomView always return nil

Change default icon for moving cells in UITableView

I need to change default icon for moving cells in UITableView.
This one:
Is it possible?
This is a really hacky solution, and may not work long term, but may give you a starting point. The re-order control is a UITableViewCellReorderControl, but that's a private class, so you can't access it directly. However, you could just look through the hierarchy of subviews and find its imageView.
You can do this by subclassing UITableViewCell and overriding its setEditing:animated: method as follows:
- (void) setEditing:(BOOL)editing animated:(BOOL)animated
{
[super setEditing: editing animated: YES];
if (editing) {
for (UIView * view in self.subviews) {
if ([NSStringFromClass([view class]) rangeOfString: #"Reorder"].location != NSNotFound) {
for (UIView * subview in view.subviews) {
if ([subview isKindOfClass: [UIImageView class]]) {
((UIImageView *)subview).image = [UIImage imageNamed: #"yourimage.png"];
}
}
}
}
}
}
Or in Swift
override func setEditing(_ editing: Bool, animated: Bool) {
super.setEditing(editing, animated: animated)
if editing {
for view in subviews where view.description.contains("Reorder") {
for case let subview as UIImageView in view.subviews {
subview.image = UIImage(named: "yourimage.png")
}
}
}
}
Be warned though... this may not be a long term solution, as Apple could change the view hierarchy at any time.
Ashley Mills' answer was excellent at the time it was offered, but as others have noted in the comments, the view hierarchy has changed from version to version of iOS. In order to properly find the reorder control, I'm using an approach that traverses the entire view hierarchy; hopefully this will give the approach an opportunity to continue working even if Apple changes the view hierarchy.
Here's the code I'm using to find the reorder control:
-(UIView *) findReorderView:(UIView *) view
{
UIView *reorderView = nil;
for (UIView *subview in view.subviews)
{
if ([[[subview class] description] rangeOfString:#"Reorder"].location != NSNotFound)
{
reorderView = subview;
break;
}
else
{
reorderView = [self findReorderView:subview];
if (reorderView != nil)
{
break;
}
}
}
return reorderView;
}
And here's the code I'm using to override the -(void) setEditing:animated: method in my subclass:
-(void) setEditing:(BOOL)editing animated:(BOOL)animated
{
[super setEditing:editing animated:animated];
if (editing)
{
// I'm assuming the findReorderView method noted above is either
// in the code for your subclassed UITableViewCell, or defined
// in a category for UIView somewhere
UIView *reorderView = [self findReorderView:self];
if (reorderView)
{
// I'm setting the background color of the control
// to match my cell's background color
// you might need to do this if you override the
// default background color for the cell
reorderView.backgroundColor = self.contentView.backgroundColor;
for (UIView *sv in reorderView.subviews)
{
// now we find the UIImageView for the reorder control
if ([sv isKindOfClass:[UIImageView class]])
{
// and replace it with the image we want
((UIImageView *)sv).image = [UIImage imageNamed:#"yourImage.png"];
// note: I have had to manually change the image's frame
// size to get it to display correctly
// also, for me the origin of the frame doesn't seem to
// matter, because the reorder control will center it
sv.frame = CGRectMake(0, 0, 48.0, 48.0);
}
}
}
}
}
Swift 4
// Change default icon (hamburger) for moving cells in UITableView
func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
let imageView = cell.subviews.first(where: { $0.description.contains("Reorder") })?.subviews.first(where: { $0 is UIImageView }) as? UIImageView
imageView?.image = #imageLiteral(resourceName: "new_hamburger_icon") // give here your's new image
imageView?.contentMode = .center
imageView?.frame.size.width = cell.bounds.height
imageView?.frame.size.height = cell.bounds.height
}
Swift version of Rick's answer with few improvements:
override func setEditing(editing: Bool, animated: Bool) {
super.setEditing(editing, animated: animated)
if editing {
if let reorderView = findReorderViewInView(self),
imageView = reorderView.subviews.filter({ $0 is UIImageView }).first as? UIImageView {
imageView.image = UIImage(named: "yourImage")
}
}
}
func findReorderViewInView(view: UIView) -> UIView? {
for subview in view.subviews {
if String(subview).rangeOfString("Reorder") != nil {
return subview
}
else {
findReorderViewInView(subview)
}
}
return nil
}
Updated solution of Ashley Mills (for iOS 7.x)
if (editing) {
UIView *scrollView = self.subviews[0];
for (UIView * view in scrollView.subviews) {
NSLog(#"Class: %#", NSStringFromClass([view class]));
if ([NSStringFromClass([view class]) rangeOfString: #"Reorder"].location != NSNotFound) {
for (UIView * subview in view.subviews) {
if ([subview isKindOfClass: [UIImageView class]]) {
((UIImageView *)subview).image = [UIImage imageNamed: #"moveCellIcon"];
}
}
}
}
}
- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath
{
for (UIControl *control in cell.subviews)
{
if ([control isMemberOfClass:NSClassFromString(#"UITableViewCellReorderControl")] && [control.subviews count] > 0)
{
for (UIControl *someObj in control.subviews)
{
if ([someObj isMemberOfClass:[UIImageView class]])
{
UIImage *img = [UIImage imageNamed:#"reorder_icon.png"];
((UIImageView*)someObj).frame = CGRectMake(0.0, 0.0, 43.0, 43.0);
((UIImageView*)someObj).image = img;
}
}
}
}
}
I use editingAccessoryView to replace reorder icon.
Make a subclass of UITableViewCell.
Override setEditing. Simply hide reorder control and set editingAccessoryView to an uiimageview with your re-order image.
- (void) setEditing:(BOOL)editing animated:(BOOL)animated
{
[super setEditing: editing animated: YES];
self.showsReorderControl = NO;
self.editingAccessoryView = editing ? [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"yourReorderIcon"]] : nil;
}
If you are not using editing accessory view, this may be a good choice.
I could not get any other answer to work for me, but I found a solution.
Grzegorz R. Kulesza's answer almost worked for me but I had to make a couple changes.
This works with Swift 5 and iOS 13:
// Change default reorder icon in UITableViewCell
func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
let imageView = cell.subviews.first(where: { $0.description.contains("Reorder") })?.subviews.first(where: { $0 is UIImageView }) as? UIImageView
imageView?.image = UIImage(named: "your_custom_reorder_icon.png")
let size = cell.bounds.height * 0.6 // scaled for padding between cells
imageView?.frame.size.width = size
imageView?.frame.size.height = size
}
I did this on iOS 12 with swift 4.2
I hope this helps:
func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
for view in cell.subviews {
if view.self.description.contains("UITableViewCellReorderControl") {
for sv in view.subviews {
if (sv is UIImageView) {
(sv as? UIImageView)?.image = UIImage(named: "your_image")
(sv as? UIImageView)?.contentMode = .center
sv.frame = CGRect(x: 0, y: 0, width: 25, height: 25)
}
}
}
}
}
After debuging the UITableViewCell, you can use KVC in UITableViewCell subclass to change it.
// key
static NSString * const kReorderControlImageKey = #"reorderControlImage";
// setting when cellForRow calling
UIImage *customImage;
[self setValue:customImage forKeyPath:kReorderControlImageKey];
// to prevent crash
- (void)setValue:(id)value forUndefinedKey:(NSString *)key {
if ([key isEqualToString:kReorderControlImageKey]) return;
else [super setValue:value forUndefinedKey:key];
}
You can also simply add your own custom reorder view above all others inside your cell.
All you have to do is ensure this custom view is always above others, which can be checked in [UITableViewDelegate tableView: willDisplayCell: forRowAtIndexPath: indexPath:].
In order to allow the standard reorder control interaction, your custom view must have its userInteractionEnabled set to NO.
Depending on how your cell looks like, you might need a more or less complex custom reorder view (to mimic the cell background for exemple).
Swift 5 solution:
Subclass UITableViewCell and override didAddSubview method:
override func didAddSubview(_ subview: UIView) {
if !subview.description.contains("Reorder") { return }
(subview.subviews.first as? UIImageView)?.removeFromSuperview()
let imageView = UIImageView()
imageView.image = UIImage()
subview.addSubview(imageView)
imageView.snp.makeConstraints { make in
make.height.width.equalTo(24)
make.centerX.equalTo(subview.snp.centerX)
make.centerY.equalTo(subview.snp.centerY)
}
}
I've used SnapKit to set constraints, you can do it in your way.
Please note, it could be temporary solution in order of Apple updates.
Working with iOS 16 and Swift 5
I tried the above solution, but sometimes my custom image was not displayed in some cells.
This code works fine for me into the UITableViewCell subclass:
private lazy var customReorderImgVw: UIImageView = {
let img = UIImage(named: "imgCustomReorder")!
let imgVw = UIImageView(image: img)
imgVw.contentMode = .center
imgVw.frame = CGRect(origin: .zero, size: img.size)
imgVw.alpha = 0
return imgVw
}()
override func setEditing(_ editing: Bool, animated: Bool) {
super.setEditing(editing, animated: animated)
if editing {
for subVw in subviews {
if "\(subVw.classForCoder)" == "UITableViewCellReorderControl" {
subVw.subviews.forEach { $0.removeFromSuperview() }
customReorderImgVw.center.y = subVw.center.y
subVw.addSubview(customReorderImgVw)
break
}
}
}
showOrHideCustomReorderView(isToShow: editing)
}
private func showOrHideCustomReorderView(isToShow: Bool) {
let newAlpha: CGFloat = (isToShow ? 1 : 0)
UIView.animate(withDuration: 0.25) {
self.customReorderImgVw.alpha = newAlpha
}
}

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