I have icons in my assets that I want to use for my tab bar, 2 for each tab (one representing not highlighted i.e just an outline, and one representing highlighted i.e all filled in). The idea is to use the outlined icons for the tabs that aren't currently selected, and the filled in one for the tab that is currently selected. How can I go about doing this?
Just make an Class for your Tabbar, for example:
class MainTabBarController: UITabBarController {
override func viewDidLoad() {
super.viewDidLoad()
for item in self.tabBar.items! as [UITabBarItem] {
// loop through all of your elements in TabBar
if let image = item.image {
item.selectedImage = your Selected Image
item.image = your base Image
}
}
}
You could store all your images in an Array containing UIImage, like:
let TabImages = [UIImage]()
let HighlightedImages = [UIImage]()
And then set them in your for each loop.
var tabBarController = self.window!.rootViewController as UITabBarController
let tabItems = tabBarController.tabBar.items as [UITabBarItem]
tabItems[2].selectedImage = UIImage(named: "tabImage1_Selected")
Related
After reading a few articles about custom UITabBarControllers, I am left more confused than before I even started doing the research in the first place.
My goal is to create a custom TabBar with 3 important properties:
No text, just icons
The active icon is marked by a circle filled with a color behind it, and therefore needs a different icon color
Here's what I am trying to achieve:
I've been able to remove the text and center the icon by following another StackOverflow answer (Remove tab bar item text, show only image), although the solution seems like a hack to me.
How would I go about creating a circle behind the item and change the active item's color?
Also, would someone mind explaining the difference between the XCode inspector sections "Tab Bar Item" and "Bar Item", which appear directly under each other?
The first step is simple: leaving the title property of the UITabbarItem empty should hide the label.
Your second step can actually be broken down into two steps: changing the color of the icon and adding a circle behind it.
The first step here is simple again: you can set a different icon to use for the currently selected ViewController (I use Storyboards, this process is pretty straightforward). What you'd do is add a white version of the icon to be shown when that menu option is selected.
The final step is displaying the circle. To do this, we'll need the following information:
Which item is currently selected?
What is the position of the icon on the screen?
The first of these two is pretty easy to find out, but the second poses a problem: the icons in a UITabBar aren't spaced around the screen equally, so we can't just divide the width of the tabbar by the amount of items in it, and then take half of that to find the center of the icons. Instead, we will subclass UITabBarController.
Note: the tabBar property of a UITabBarController does have a .selectionIndicatorImage property. You can assign an image to this and it will be shown behind your icon. However, you can't easily control the placement of this image, and that is why we still resort to subclassing UITabBarController.
class CircledTabBarController: UITabBarController {
var circle: UIView?
override func viewDidLoad() {
super.viewDidLoad()
let numberOfItems = CGFloat(tabBar.items!.count)
let tabBarItemSize = CGSize(width: (tabBar.frame.width / numberOfItems) - 20, height: tabBar.frame.height)
circle = UIView(frame: CGRect(x: 0, y: 0, width: tabBarItemSize.height, height: tabBarItemSize.height))
circle?.backgroundColor = .darkGray
circle?.layer.cornerRadius = circle!.frame.width/2
circle?.alpha = 0
tabBar.addSubview(circle!)
tabBar.sendSubview(toBack: circle!)
}
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
let index = -(tabBar.items?.index(of: tabBar.selectedItem!)?.distance(to: 0))!
let frame = frameForTabAtIndex(index: index)
circle?.center.x = frame.origin.x + frame.width/2
circle?.alpha = 1
}
override func tabBar(_ tabBar: UITabBar, didSelect item: UITabBarItem) {
let index = -(tabBar.items?.index(of: item)?.distance(to: 0))!
let frame = frameForTabAtIndex(index: index)
self.circle?.center.x = frame.origin.x + frame.width/2
}
func frameForTabAtIndex(index: Int) -> CGRect {
var frames = tabBar.subviews.compactMap { (view:UIView) -> CGRect? in
if let view = view as? UIControl {
for item in view.subviews {
if let image = item as? UIImageView {
return image.superview!.convert(image.frame, to: tabBar)
}
}
return view.frame
}
return nil
}
frames.sort { $0.origin.x < $1.origin.x }
if frames.count > index {
return frames[index]
}
return frames.last ?? CGRect.zero
}
}
Now use this subclass of UITabBarController instead of the base class.
So why this approach over simply changing the icon to a circled one? Because you can do many different things with this. I wrote an article about animating the UITabBarController in a similar manner, and if you like, you can easily use above implementation to add animation to yours too.
The easiest and actually cleanest way to do it is to design your icons and import them as images to the .xcassets folder. Then you can just set the different icons for the different states for each of the viewControllers with:
ViewController.tabBarItem = UITabBarItem(title: "", image: yourImage.withRenderingMode(.alwaysOriginal), selectedImage: yourImage)
your selected image will be the one with the circle and the image will be without. It is way easier than manipulating the images in xcode and it is also less expensive since the compiler only has to render the images and doesn't have to manipulate them.
About the other question UIBarItem is
An abstract superclass for items that can be added to a bar that appears at the bottom of the screen.
UITabBarItem is a subclass of UIBarItem to provide extra funtionality.
I'm trying set background image for UINavigationBar but status bar always white color
Result
My code
self.navigationController?.navigationBar.setBackgroundImage(UIImage(named:"bg_nav")?.resizableImage(withCapInsets: UIEdgeInsets.zero, resizingMode: .stretch), for: .default)
Expected result image background fill include status bar
Just integrate below function inside your viewController where your need to change the status bar appearance.
func setStatusBarBackgroundColor(color: UIColor) {
guard let statusBar = UIApplication.shared.value(forKeyPath: "statusBarWindow.statusBar") as? UIView else { return }
statusBar.backgroundColor = color
}
uses: self.setStatusBarBackgroundColor(color: yourColor)
You can apply this to the whole app using common viewController and make this viewController to the sub class of other viewController's, by usign this approach you dont need to write this code again.
You can Do like that
extension UINavigationController{
func setNavBarImage(_ image:UIImage?) {
guard let image = image else {return}
self.navigationBar.setBackgroundImage(image, for: .default)
self.navigationBar.shadowImage = UIImage()
self.navigationBar.isTranslucent = true
//clear statusBar color
let statusBar = UIApplication.shared.value(forKeyPath: "statusBarWindow.statusBar") as? UIView
statusBar?.backgroundColor = UIColor.clear
}
}
And in ViewController used like that
self.navigationController?.setNavBarImage(UIImage(named: "NavigationBar"))
Result
How can I change the background colour for each tab in an iOS application in Swift, as shown in the image?
This can be implemented with the help of setting images on each tab:
let aryTabImages = ["home-icon.png","help-icon.png","photos-icon.png","cart-icon.png","search-icon.png"]
Assign to each tabbar item:
for (index, item) in self.tabBarController!.tabBar.items!.enumerate() {
item.image = UIImage(named: aryTabImages.objectAtIndex(index) as! String)!.imageWithRenderingMode(.AlwaysOriginal)
item.selectedImage = UIImage(named: aryTabImages.objectAtIndex(index) as! String)!.imageWithRenderingMode(.AlwaysOriginal)
}
Also Make sure about:
Tabbar item height for each IOS device
Tint color correctly selected of UITabbarController's tabbar.
I have UITabBarController with view
So on every TabBar I have ViewController. But on my center UITabBarItem I need to call something like modal UIViewController. And It should be like this
My UITabBarController class look like
class PlanetTabBarController: UITabBarController {
override func viewDidLoad() {
super.viewDidLoad()
self.tabBar.tintColor = kTintColor
var items = self.tabBar.items as! [UITabBarItem]
let centredTabBar:UITabBarItem = items[2]
self.tabBar.layer.borderWidth = 0.50
centredTabBar.image = ktabCentredBarImage
self.tabBar.layer.borderColor = UIColor.clearColor().CGColor
self.tabBar.layer.borderWidth = 0
self.tabBar.shadowImage = UIImage()
// self.tabBar.backgroundImage = ktabBarImage
self.tabBar.backgroundImage?.imageWithAlignmentRectInsets
print( UIDevice.currentDevice().modelName)
if( UIDevice.currentDevice().modelName != "iPhone 6" && UIDevice.currentDevice().modelName != "iPhone 6 Plus") {
self.tabBar.backgroundImage = ktabBarImage
}
if( UIDevice.currentDevice().modelName == "iPad 2" ) {
self.tabBar.backgroundImage = ktabBarImage
}
if let font = UIFont(name: "Avenir-Black", size: 10) {
let appearance = UITabBarItem.appearance()
let attributes = [NSFontAttributeName:font]
appearance.setTitleTextAttributes(attributes, forState: UIControlState.Normal)
}
}
}
I really have no idea how to override standart calling of UIViewController and call modal like this =) Please give me advice where I need to search
You can either place a UIButton in the same area as the UITabBarItem and fire an action or you can simply fire an action when the selectedSegmentIndex changes("value changed" in IB) for the UITabBar after creating a center UITabBarItem. The design choice is yours. The first step is to understand the objects you're working with. It would probably be easier to just add a button, center aligned, over top of the standard UITabBar at the bottom so you don't deal with a custom UITabBarController to handle that non-uniform image above the tab bar.
Or just create your own TabBar down there. It's very simply to setup a few UIButtons or UIViews next to one another that don't have a static height such as a UITabBarController which would allow for that center object.
UITabBarController
UIViewController
Presenting a ViewController
At the moment I have a standard tab bar, when tapped goes to its corresponding viewController. But I want to make a menu pop out from tab bar when more tab is selected, as shown in below image.
Is any suggestion to implement this?
Thanks in advance.
I would recommend you do so:
First, you should think of all the tab types that could be in tab bar. On your screenshot there are tabs, that present controller, and tab, that presents menu. So we could create enum with all these types:
enum TabType {
case controller
case menu
}
After that you can store array of tab types in order they are shown in tab bar, for your screenshot like so
let tabTypes: [TabType] = [.controller, .controller, .controller, .controller, .menu]
Then you should implement UITabBarControllerDelegate's func tabBarController(_:, shouldSelect:) -> Bool method, which returns true if tab bar is allowed to select the passed controller, and false otherwise.
If you return true than all other work (like presenting view controller and other stuff) tab bar controller will do for you.
In your case you want to execute custom action on tab click, so you should return false. Before returning you should present your menu.
func tabBarController(_ tabBarController: UITabBarController, shouldSelect viewController: UIViewController) -> Bool {
if let index = tabBarController.viewControllers?.index(of: viewController),
index < tabBarTypes.count {
let type = tabBarTypes[index]
switch type {
case .menu:
// perform your menu presenting here
return false
case .controller:
// do nothing, just return true, tab bar will do all work for you
return true
}
}
return true
}
In this implementation you can easily change tab types order or add some another tab type and handle it appropriate.
Its not good UI but although if you want.
First You have to implement delegate method of UITabbarControllerDelegate as below
func tabBarController(_ tabBarController: UITabBarController, shouldSelect
viewController: UIViewController) -> Bool {
if viewController.classForCoder == moreViewController.self
{
let popvc = MoreSubMenuViews(nibName: "MoreSubMenuViews", bundle: Bundle.main)
self.addChildViewController(popvc)
let tabbarHeight = tabBar.frame.height
let estimatedWidth:CGFloat = 200.0
let estimatedHeight:CGFloat = 300.0
popvc.view.frame = CGRect(x:self.view.frame.width - estimatedWidth, y: self.view.frame.height - estimatedHeight - tabbarHeight, width: estimatedWidth, height: estimatedHeight)
self.view.addSubview(popvc.view)
popvc.didMove(toParentViewController: self)
print("sorry stop here")
return true // if you want not to select return false here
}else{
//remove popup logic here if opened
return true
}
}
Here moreViewController is last tab controller & MoreSubMenuViews is nib/xib file which contains buttons shown in you image.
Instead of showing a menu, you could use a scrollable tabs view for a better UI. If you prefer using a library, here's a simple scrollable tab-bar you could implement.
This is an abuse of the UI patterns layout in Apples HIG. Specifically:
Use a tab bar strictly for navigation. Tab bar buttons should not be used to perform actions. If you need to provide controls that act on elements in the current view, use a toolbar instead.
This control should be used to flatten your app hierarchy. It seems that in this case you are mixing functionality of the button. Sometimes it selects a separate view controller, sometimes it displays a action list. This is a confusing situation for users and should be avoided.
A way you could achieve this and still adhere to HIG is by using navigation or tool bars. Imbed this control in a toolbar button. The most simple case would be to invoke a UIActionController with the .actionSheet style selected.
As per my understanding what you want is that, tab 1 is selected and user goes to tab 5 then background will be tab 1 & vice-versa for tab 2,3 & 4 and there should be pop up like buttons as shown in your image. please correct me if I'm wrong.
For this you have to capture the image while user navigate through tabs.
Please find below code in AppDelegate,
var currentImage: UIImage! //It will be public variable
Tabbar delegate methods,
func tabBarController(_ tabBarController: UITabBarController, didSelect viewController: UIViewController) {
if tabBarController.selectedIndex == 4 {
let moreVC = tabBarController.selectedViewController as! MoreVC
moreVC.currentImage = currentImage
}
}
func tabBarController(_ tabBarController: UITabBarController, shouldSelect viewController: UIViewController) -> Bool {
if tabBarController.selectedIndex != 4 {
let navController = tabBarController.selectedViewController as! UINavigationController
let viewController = navController.viewControllers.last
currentImage = Common.imageWithView(inView: (viewController?.navigationController?.view)!) //UIImage(view: (viewController?.navigationController?.view)!)
}
return true
}
Here I've taken static 4 as last tab index & MoreVC will be the associated ViewController of tab index 4.
Common class to get image from view,
class Common {
static func imageWithView(inView: UIView) -> UIImage? {
UIGraphicsBeginImageContextWithOptions(inView.bounds.size, inView.isOpaque, 0.0)
defer { UIGraphicsEndImageContext() }
if let context = UIGraphicsGetCurrentContext() {
inView.layer.render(in: context)
let image = UIGraphicsGetImageFromCurrentImageContext()
return image
}
return nil
}
}
Please find MoreVC,
#IBOutlet weak var imageView: UIImageView!
var currentImage: UIImage! {
didSet {
imageView.image = currentImage
}
}
Please find below image for MoreVC Storyboard. Look it does not contain NavigationController like all other ViewControllers.
Let me know in case of any queries.
1)
Create a "Tab5ViewController" and use this:
static func takeScreenshot(bottomPadding padding: CGFloat = 0) -> UIImage? {
let layer = UIApplication.shared.keyWindow!.layer
let scale = UIScreen.main.scale
UIGraphicsBeginImageContextWithOptions(CGSize(width: layer.frame.size.width, height: layer.frame.size.height - padding), false, scale)
guard let context = UIGraphicsGetCurrentContext() else { return nil }
layer.render(in: context)
let screenshot = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return screenshot
}
Use the screenshot as a background image for your "Tab5ViewController"
2) In your "Tab5ViewController" you can have the stack component (the additional tabs) and then just add/remove child view controllers based on the selection
3)
fix edge cases (like tab selection highlight and so on...)