Key board will show notification. does not give notification of keyboard appearing - ios

Question

I have the following notification setup in my viewDidLoad() of my custom keyboard extension:
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: UIResponder.keyboardWillShowNotification, object: nil)
and this is the function I call outside of my viewDidLoad():
#objc func keyboardWillShow(_ notification: NSNotification) {
if let keyboardRect = (notification.userInfo?[UIResponder.keyboardFrameEndUserInfoKey] as? NSValue)?.cgRectValue {
print(keyboardRect.height)
ScreenHeight = Int(keyboardRect.height)
}
}
However, I set a breakpoint inside of my keyboardWillShow() function and it is never triggered. Is there something else I have to do to get the size of the keyboard before it shows?
I am trying to dynamically adjust the size of elements programmatically inserted into my keyboard.
Let me know if more information is necessary or if this is an obvious fix.
Full Code:
class KeyboardViewController: UIInputViewController {
#IBOutlet var nextKeyboardButton: UIButton! = UIButton(type: .system)
var centralManager: CBCentralManager!
var NUB5: CBPeripheral!
var characteristics = [CBCharacteristic]()
var connection: UILabel = UILabel()
var serialNum: UILabel = UILabel()
var serial: String = ""
var ScreenHeight = 0
let cornerRadii = 4
//setup Number buttons
var num1: UIButton = UIButton()
var num2: UIButton = UIButton()
var num3: UIButton = UIButton()
var num4: UIButton = UIButton()
var num5: UIButton = UIButton()
var num6: UIButton = UIButton()
var num7: UIButton = UIButton()
var num8: UIButton = UIButton()
var num9: UIButton = UIButton()
var num0: UIButton = UIButton()
var spaceBar: UIButton = UIButton()
var plus: UIButton = UIButton()
var minus: UIButton = UIButton()
var back: UIButton = UIButton()
var left: UIButton = UIButton()
var right: UIButton = UIButton()
var period: UIButton = UIButton()
var comma: UIButton = UIButton()
var returnKey: UIButton = UIButton()
let screensize: CGRect = UIScreen.main.bounds
override func updateViewConstraints() {
super.updateViewConstraints()
// Add custom view sizing constraints here
}
override func viewDidLoad() {
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow(_:)), name: UIResponder.keyboardDidChangeFrameNotification, object: nil)
var keyboard: UIView!
func loadInterface() {
// load the nib file
var calculatorNib = UINib(nibName: "keyboard", bundle: nil)
// instantiate the view
keyboard = (calculatorNib.instantiate(withOwner: self, options: nil)[0] as! UIView)
// add the interface to the main view
view.addSubview(keyboard)
// copy the background color
view.backgroundColor = keyboard.backgroundColor
ScreenHeight = Int(self.accessibilityFrame.height)
print(ScreenHeight)
}
super.viewDidLoad()
loadInterface()
self.centralManager = CBCentralManager(delegate: self, queue: nil)
//Setup Labels
let width = screensize.width
let height = CGFloat(200) //subtract 10 from total screensize to give space for connection indicator
let screensize = self.view.bounds.size
//ScreenHeight = Int(height)
connection.frame = CGRect(x: 0,y: 0,width: width,height: 10)
//TODO
serialNum.frame = CGRect(x: width/2+5, y:10,width: width/2 - 10,height:15)
spaceBar.frame = CGRect(x: width*4/5+4, y: height/4+10, width: width/5, height: height/4)
num1.frame = CGRect(x:width/5,y: 10, width: width/5,height: height/4)
num2.frame = CGRect(x:width*2/5,y: 10, width: width/5,height: height/4)
num3.frame = CGRect(x:width*3/5,y: 10, width: width/5,height: height/4)
num4.frame = CGRect(x:width/5+1,y: height/4+10, width: width/5,height: height/4)
num5.frame = CGRect(x:width*2/5+2,y: height/4+10, width: width/5,height: height/4)
num6.frame = CGRect(x:width*3/5+3,y: height/4+10, width: width/5,height: height/4)
num7.frame = CGRect(x:width/5+1,y: height/2+10, width: width/5,height: height/4)
num8.frame = CGRect(x:width*2/5+2,y: height/2+10, width: width/5,height: height/4)
num9.frame = CGRect(x:width*3/5+3,y: height/2+10, width: width/5,height: height/4)
num0.frame = CGRect(x:width*2/5+3,y: 3*height/4+10, width: width/5,height: height/4)
plus.frame = CGRect(x:0,y: 10, width: width/5,height: height/4)
minus.frame = CGRect(x:0,y: height/4+10, width: width/5,height: height/4)
back.frame = CGRect(x:width*4/5,y:10,width:width/5,height:height/4)
right.frame = CGRect(x: width*4/5+4, y: height/2+10, width: width/5, height: height/4)
left.frame = CGRect(x:0,y: height/2+10, width: width/5,height: height/4)
nextKeyboardButton.frame = CGRect(x:0,y: 3*height/4+10, width: width/5,height: height/4)
period.frame = CGRect(x:width/5,y: 3*height/4+10, width: width/5,height: height/4)
comma.frame = CGRect(x:width*3/5+2,y: 3*height/4+10, width: width/5,height: height/4)
returnKey.frame = CGRect(x:width*4/5+3,y: height*3/4+10, width: width/5,height: height/4)
num1.addTarget(self,action: #selector(addOne), for: .touchUpInside)
num2.addTarget(self,action: #selector(addTwo), for: .touchUpInside)
num3.addTarget(self,action: #selector(addThree), for: .touchUpInside)
num4.addTarget(self,action: #selector(addFour), for: .touchUpInside)
num5.addTarget(self,action: #selector(addFive), for: .touchUpInside)
num6.addTarget(self,action: #selector(addSix), for: .touchUpInside)
num7.addTarget(self,action: #selector(addSeven), for: .touchUpInside)
num8.addTarget(self,action: #selector(addEight), for: .touchUpInside)
num9.addTarget(self,action: #selector(addNine), for: .touchUpInside)
num0.addTarget(self,action: #selector(addZero), for: .touchUpInside)
spaceBar.addTarget(self,action: #selector(space), for: .touchUpInside)
plus.addTarget(self, action: #selector(plusSign), for: .touchUpInside)
minus.addTarget(self, action: #selector(minusSign), for: .touchUpInside)
back.addTarget(self, action: #selector(deleteOne), for: .touchUpInside)
left.addTarget(self, action: #selector(leftOne), for: .touchUpInside)
right.addTarget(self, action: #selector(rightOne), for: .touchUpInside)
nextKeyboardButton.addTarget(self, action: #selector(handleInputModeList(from:with:)), for: .allTouchEvents)
period.addTarget(self, action: #selector(addPeriod), for: .touchUpInside)
comma.addTarget(self, action: #selector(addComma), for: .touchUpInside)
returnKey.addTarget(self, action: #selector(returnButton), for: .touchUpInside)
num1.setTitle("1", for: .normal)
num2.setTitle("2", for: .normal)
num3.setTitle("3", for: .normal)
num4.setTitle("4", for: .normal)
num5.setTitle("5", for: .normal)
num6.setTitle("6", for: .normal)
num7.setTitle("7", for: .normal)
num8.setTitle("8", for: .normal)
num9.setTitle("9", for: .normal)
num0.setTitle("0", for: .normal)
spaceBar.setTitle("SPACE", for: .normal)
back.setTitle("<-", for: .normal)
plus.setTitle("+", for: .normal)
minus.setTitle("-", for: .normal)
left.setTitle("<", for: .normal)
right.setTitle(">", for: .normal)
nextKeyboardButton.setTitle("NEXT", for: .normal)
period.setTitle(".", for: .normal)
comma.setTitle(",", for: .normal)
returnKey.setTitle("Return", for: .normal)
num1.layer.cornerRadius = CGFloat(cornerRadii)
num2.layer.cornerRadius = CGFloat(cornerRadii)
num3.layer.cornerRadius = CGFloat(cornerRadii)
num4.layer.cornerRadius = CGFloat(cornerRadii)
num5.layer.cornerRadius = CGFloat(cornerRadii)
num6.layer.cornerRadius = CGFloat(cornerRadii)
num7.layer.cornerRadius = CGFloat(cornerRadii)
num8.layer.cornerRadius = CGFloat(cornerRadii)
num9.layer.cornerRadius = CGFloat(cornerRadii)
num0.layer.cornerRadius = CGFloat(cornerRadii)
spaceBar.layer.cornerRadius = CGFloat(cornerRadii)
plus.layer.cornerRadius = CGFloat(cornerRadii)
minus.layer.cornerRadius = CGFloat(cornerRadii)
back.layer.cornerRadius = CGFloat(cornerRadii)
left.layer.cornerRadius = CGFloat(cornerRadii)
right.layer.cornerRadius = CGFloat(cornerRadii)
nextKeyboardButton.layer.cornerRadius = CGFloat(cornerRadii)
period.layer.cornerRadius = CGFloat(cornerRadii)
comma.layer.cornerRadius = CGFloat(cornerRadii)
returnKey.layer.cornerRadius = CGFloat(cornerRadii)
num5.layer.borderWidth = CGFloat(1)
num1.setTitleColor(UIColor.black, for: .normal)
num2.setTitleColor(UIColor.black, for: .normal)
num3.setTitleColor(UIColor.black, for: .normal)
num4.setTitleColor(UIColor.black, for: .normal)
num5.setTitleColor(UIColor.black, for: .normal)
num6.setTitleColor(UIColor.black, for: .normal)
num7.setTitleColor(UIColor.black, for: .normal)
num8.setTitleColor(UIColor.black, for: .normal)
num9.setTitleColor(UIColor.black, for: .normal)
num0.setTitleColor(UIColor.black, for: .normal)
spaceBar.setTitleColor(UIColor.black, for: .normal)
plus.setTitleColor(UIColor.black, for: .normal)
minus.setTitleColor(UIColor.black, for: .normal)
back.setTitleColor(UIColor.black, for: .normal)
left.setTitleColor(UIColor.black, for: .normal)
right.setTitleColor(UIColor.black, for: .normal)
period.setTitleColor(UIColor.black, for: .normal)
comma.setTitleColor(UIColor.black, for: .normal)
nextKeyboardButton.setTitleColor(UIColor.black, for: .normal)
returnKey.setTitleColor(UIColor.black, for: .normal)
num1.backgroundColor = UIColor.white
num2.backgroundColor = UIColor.white
num3.backgroundColor = UIColor.white
num4.backgroundColor = UIColor.white
num5.backgroundColor = UIColor.white
num6.backgroundColor = UIColor.white
num7.backgroundColor = UIColor.white
num8.backgroundColor = UIColor.white
num9.backgroundColor = UIColor.white
num0.backgroundColor = UIColor.white
spaceBar.backgroundColor = UIColor.white
plus.backgroundColor = UIColor.white
minus.backgroundColor = UIColor.white
back.backgroundColor = UIColor.white
left.backgroundColor = UIColor.white
right.backgroundColor = UIColor.white
nextKeyboardButton.backgroundColor = UIColor.white
period.backgroundColor = UIColor.white
comma.backgroundColor = UIColor.white
returnKey.backgroundColor = UIColor.white
connection.text = "No Connection"
serialNum.text = "-"
connection.backgroundColor = UIColor.white
serialNum.backgroundColor = UIColor.white
connection.layer.cornerRadius = 4
serialNum.layer.cornerRadius = 4
self.view.addSubview(connection)
self.view.addSubview(serialNum)
self.view.addSubview(spaceBar)
self.view.addSubview(num1)
self.view.addSubview(num2)
self.view.addSubview(num3)
self.view.addSubview(num4)
self.view.addSubview(num5)
self.view.addSubview(num6)
self.view.addSubview(num7)
self.view.addSubview(num8)
self.view.addSubview(num9)
self.view.addSubview(num0)
self.view.addSubview(plus)
self.view.addSubview(minus)
self.view.addSubview(back)
self.view.addSubview(left)
self.view.addSubview(right)
self.view.addSubview(period)
self.view.addSubview(comma)
self.view.addSubview(nextKeyboardButton)
self.view.addSubview(returnKey)
}
#objc func returnButton(sender: UIButton){
textDocumentProxy.insertText("\n")
}
#objc func addPeriod(sender: UIButton){
textDocumentProxy.insertText(".")
}
#objc func addComma(sender: UIButton){
textDocumentProxy.insertText(",")
}
#objc func leftOne(sender: UIButton){
textDocumentProxy.adjustTextPosition(byCharacterOffset: -1)
}
#objc func rightOne(sender: UIButton){
textDocumentProxy.adjustTextPosition(byCharacterOffset: 1)
}
#objc func deleteOne(sender: UIButton){
textDocumentProxy.deleteBackward()
}
#objc func plusSign(sender: UIButton){
textDocumentProxy.insertText("+")
}
#objc func minusSign(sender: UIButton){
textDocumentProxy.insertText("-")
}
#objc func space(sender: UIButton){
textDocumentProxy.insertText(" ")
}
#objc func addOne(sender: UIButton){
textDocumentProxy.insertText("1")
textDocumentProxy.insertText(String(ScreenHeight))
}
#objc func addTwo(sender: UIButton){
textDocumentProxy.insertText("2")
}
#objc func addThree(sender: UIButton){
textDocumentProxy.insertText("3")
}
#objc func addFour(sender: UIButton){
textDocumentProxy.insertText("4")
}
#objc func addFive(sender: UIButton){
textDocumentProxy.insertText("5")
}
#objc func addSix(sender: UIButton){
textDocumentProxy.insertText("6")
}
#objc func addSeven(sender: UIButton){
textDocumentProxy.insertText("7")
}
#objc func addEight(sender: UIButton){
textDocumentProxy.insertText("8")
}
#objc func addNine(sender: UIButton){
textDocumentProxy.insertText("9")
}
#objc func addZero(sender: UIButton){
textDocumentProxy.insertText("0")
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
if self.centralManager.state == CBManagerState.poweredOn {
self.centralManager.scanForPeripherals(withServices: [lairdUUID], options: nil)
}
}
#objc func keyboardWillShow(_ notification: NSNotification) {
if let userInfo = notification.userInfo as? Dictionary<String, AnyObject>{
let frame = userInfo[UIResponder.keyboardFrameEndUserInfoKey]
let keyBoardRect = frame?.cgRectValue
ScreenHeight = Int(keyBoardRect!.height)
}
}
override func viewWillDisappear(_ animated: Bool) {
// super.viewWillDisappear(animated)
// if let centralManager = self.centralManager {
// if centralManager.state == CBManagerState.poweredOn {
// if let NUB5 = self.NUB5 {
// if peripheral.state == CBPeripheralState.connected {
// centralManager.cancelPeripheralConnection(NUB5)
// }
// }
// }
// }
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated
}
override func textWillChange(_ textInput: UITextInput?) {
// The app is about to change the document's contents. Perform any preparation here.
}
override func textDidChange(_ textInput: UITextInput?) {
// The app has just changed the document's contents, the document context has been updated.
}

Answer 1

For prevent crashes and for the best practice use
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow), name: UIResponder.keyboardWillShowNotification, object: nil)
on viewWillAppear.

Answer 2

Since your method keyboardWillShow has a parameter you should change the syntax accordingly to inform the compiler exactly the method that it has to look for.
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow(_:)), name: UIResponder.keyboardWillShowNotification, object: nil)
What was happening is that the compiler will search for the method keyboardWillShow without any parameters which is not there, Hence doesn't execute anything.