I have six button i want that user must select any of the six button before moving to next screen if it does not select any then it should not move to next screen I have read to use BOOL flag but this show which button is clicked i want that if any of the six buttons is clicked then user can move to next screen
-(IBAction)locationOneButtonAction{
// your stuff
_flag = YES;
}
-(IBAction)locationTwoButtonAction{
// your stuff
_flag = YES;
}
I think the best solution this problem is to declare a bool for your class (let's say it is called "ClickViewController" like (so at the top)
#interface ClickViewController () {
bool wasClicked;
}
...
-(IBAction)locationOneButtonAction{
// your stuff
wasClicked = YES;
}
Then when the button that should move to the next page is clicked utilize a method like this.
-(void)nextPageClicked{
if (wasClicked){
[self performSegueWithIdentifier:#"segueIdentifier" sender: self];
} else {
// do something else here, like tell the user why you didn't move them
}
}
This means that you cannot draw the segue from the button to the next view. If you are using storyboards, this means that you can't draw the segue from the button that is supposed to move it to the next view, rather you should draw it from the view controller icon to the next view. Then select the segue, name it, and use the method above with the name.
I'm also not sure if you mean that you want each of the buttons to move to the next view, if that is the case, you can use basically the same code, but just put the code [self performSegueWithIdentifier:#"segueIdentifier" sender: self]; line in action for the button.
Hopefully this helps.
Intially add BOOL _flag; int curIndex; in .h file.
Now add intially _flag = FALSE; in viewDidLoad method as it indicate no button clicked.
Make userInteractionEnabled for each button to be able to click and add tag to each button.
Now in action method of each click of button do this:
(IBAction)locationOneButtonAction:(id)sender{
curIndex = [sender tag]; //which button clicked
// your stuff
_flag = TRUE;
}
-(IBAction)locationTwoButtonAction{
curIndex = [sender tag]; //which button clicked
// your stuff
_flag = YES;
}
........
........
Now check like this if button clicked:
if(_flag)
{
NSLog(#"Button clicked with tag: %d",curIndex);
}
else
{
NSLog(#"Not any Button clicked");
}
I want to get a pointer reference to UIKeyboard *keyboard to the keyboard on screen so that I can add a transparent subview to it, covering it completely, to achieve the effect of disabling the UIKeyboard without hiding it.
In doing this, can I assume that there's only one UIKeyboard on the screen at a time? I.e., is it a singleton? Where's the method [UIKeyboard sharedInstance]. Brownie points if you implement that method via a category. Or, even more brownie points if you convince me why it's a bad idea to assume only one keyboard and give me a better solution.
Try this:
// my func
- (void) findKeyboard {
// Locate non-UIWindow.
UIWindow *keyboardWindow = nil;
for (UIWindow *testWindow in [[UIApplication sharedApplication] windows]) {
if (![[testWindow class] isEqual:[UIWindow class]]) {
keyboardWindow = testWindow;
break;
}
}
// Locate UIKeyboard.
UIView *foundKeyboard = nil;
for (UIView *possibleKeyboard in [keyboardWindow subviews]) {
// iOS 4 sticks the UIKeyboard inside a UIPeripheralHostView.
if ([[possibleKeyboard description] hasPrefix:#"<UIPeripheralHostView"]) {
possibleKeyboard = [[possibleKeyboard subviews] objectAtIndex:0];
}
if ([[possibleKeyboard description] hasPrefix:#"<UIKeyboard"]) {
foundKeyboard = possibleKeyboard;
break;
}
}
}
How about using -[UIApplication beginIgnoringInteractionEvents]?
Also, another trick to get the view containing the keyboard is to initialize a dummy view with CGRectZero and set it as the inputAccessoryView of your UITextField or UITextView. Then, get its superview. Still, such shenanigans is private/undocumented, but I've heard of apps doing that and getting accepted anyhow. I mean, how else would Instagram be able to make their comment keyboard interactive (dismiss on swipe) like the Messages keyboard?
I found that developerdoug's answer wasn't working on iOS 7, but by modifying things slightly I managed to get access to what I needed. Here's the code I used:
-(UIView*)findKeyboard
{
UIView *keyboard = nil;
for (UIWindow* window in [UIApplication sharedApplication].windows)
{
for (UIView *possibleKeyboard in window.subviews)
{
if ([[possibleKeyboard description] hasPrefix:#"<UIPeripheralHostView"])
{
keyboard = possibleKeyboard;
break;
}
}
}
return keyboard;
}
From what I could make out, in iOS 7 the keyboard is composed of a UIPeripheralHostView containing two subviews: a UIKBInputBackdropView (which provides the blur effect on whatever's underneath the keyboard) and a UIKeyboardAutomatic (which provides the character keys). Manipulating the UIPeripheralHostView seems to be equivalent to manipulating the entire keyboard.
Discaimer: I have no idea whether Apple will accept an app that uses this technique, nor whether it will still work in future SDKs.
Be aware, Apple has made it clear that applications which modify private view hierarchies without explicit approval beforehand will be rejected. Take a look in the Apple Developer Forums for various developers' experience on the issue.
If you're just trying to disable the keyboard (prevent it from receiving touches), you might try adding a transparent UIView that is the full size of the screen for the current orientation. If you add it as a subview of the main window, it might work. Apple hasn't made any public method of disabling the keyboard that I'm aware of - you might want to use one of your support incidents with Apple, maybe they will let you in on the solution.
For an app I am currently developing I am using a really quick and easy method:
Add this in the header file:
// Add in interface
UIWindow * _window;
// Add as property
#property (strong, nonatomic) IBOutlet UIView * _keyboard;
Then add this code in the bottom of the keyboardWillShow function:
-(void) keyboardWillShow: (NSNotification *) notification {
.... // other keyboard will show code //
_window = [UIApplication sharedApplication].windows.lastObject;
[NSTimer scheduledTimerWithTimeInterval:0.05
target:self
selector:#selector(allocateKeyboard)
userInfo:nil
repeats:NO];
}
This code look for when the keyboard is raised and then allocates the current window. I have then added a timer to allocate the keyboard as there were some issues when allocated immediately.
- (void)allocateKeyboard {
if (!_keyboard) {
if (_window.subviews.count) {
// The keyboard is always the 0th subview
_keyboard = _window.subviews[0];
}
}
}
We now have the keyboard allocated which gives you direct "access" to the keyboard as the question asks.
Hope this helps
Under iOS 8 it appears you have to jump down the chain more than in the past. The following works for me to get the keyboard, although with custom keyboards available and such I wouldn't rely on this working unless you're running in a controlled environment.
- (UIView *)findKeyboard {
for (UIWindow* window in [UIApplication sharedApplication].windows) {
UIView *inputSetContainer = [self viewWithPrefix:#"<UIInputSetContainerView" inView:window];
if (inputSetContainer) {
UIView *inputSetHost = [self viewWithPrefix:#"<UIInputSetHostView" inView:inputSetContainer];
if (inputSetHost) {
UIView *kbinputbackdrop = [self viewWithPrefix:#"<_UIKBCompatInput" inView:inputSetHost];
if (kbinputbackdrop) {
UIView *theKeyboard = [self viewWithPrefix:#"<UIKeyboard" inView:kbinputbackdrop];
return theKeyboard;
}
}
}
}
return nil;
}
- (UIView *)viewWithPrefix:(NSString *)prefix inView:(UIView *)view {
for (UIView *subview in view.subviews) {
if ([[subview description] hasPrefix:prefix]) {
return subview;
}
}
return nil;
}
I am trying to hide and display a UIView on BarButtonItem click. Priviously i also posted the question regarding same but didnt find any suitable answer. I created UIView manually in IB and just placed it in view so it must be shown as soon as view is loaded but i made it hidden in viewDidLoad method by writing
myvew.hidden = YES;
secondly, when i click BarButtonItem then i set
-(IBAction)mymethod
{
myview.hidden = NO;
}
so its diplaying view but when i again click on it it must hide.. how do i do it?
Put the following statement in your button action
myview.hidden = !myview.hidden ;
So your code must be like below.
-(IBAction)mymethod
{
myview.hidden = !myview.hidden ;
}
if (myview.hidden == YES)
{
myview.hidden = NO;
}
else
{
myview.hidden = YES;
}
Check if the view is already hidden and then show, and if not hidden then hide it.
You should do in this way
-(IBAction)mymethod
{
if( myview.hidden == NO ) myview.hidden = YES;
else myview.hidden = NO;
}
I have alert view having 2 buttons "OK" and "Cancel" and a textfield.
Now i want to disable "OK" button until user enter some text in textfield.
How can i do this?
thanks in advance
UPDATE 2: For Swift 5.1
<#your alert controller#>.addTextField {(tf) in
//... set your tf characteristics i.e .keyboardType here
NotificationCenter.default.addObserver(forName: UITextField.textDidChangeNotification,
object: tf,
queue: OperationQueue.main) { _ in
//enable or disable the selected action depending on whether the textField text is empty
<#your alert controller#>.actions[0].isEnabled = !tf.text!.isEmpty
}
}
posting this to update the response since ios 5 :
- (BOOL)alertViewShouldEnableFirstOtherButton:(UIAlertView *)alertView
{
UITextField *textField = [alertView textFieldAtIndex:0];
if ([textField.text length] == 0)
{
return NO;
}
return YES;
}
UPDATE:iOS 8 Since Apple have deprecated the UIAlertView in favour of the UIAlertController. There is no longer a delegate call to alertViewShouldEnableFirstOtherButton:
So instead you would set the buttons enabled property via the UITextFieldTextDidChangeNotification
Add a textView to the alert with
(void)addTextFieldWithConfigurationHandler:(void (^)(UITextField *textField))configurationHandler
[<#your alert#> addTextFieldWithConfigurationHandler:^(UITextField *textField) {
textField.delegate = self;
textField.tag = 0; //set a tag to 0 though better to use a #define
}];
Then implement the delegate method
(void)textFieldDidBeginEditing:(UITextField *)textField
- (void)textFieldDidBeginEditing:(UITextField *)textField{
//in here we want to listen for the "UITextFieldTextDidChangeNotification"
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(textFieldHasText:)
name:UITextFieldTextDidChangeNotification
object:textField];
}
When the text in textField changes it will invoke a call to "textFieldHasText:" and pass along a NSNotification*
-(void)textFieldHasText:(NSNotification*)notification{
//inside the notification is the object property which is the textField
//we cast the object to a UITextField*
if([[(UITextField*)notification.object text] length] == 0){
//The UIAlertController has actions which are its buttons.
//You can get all the actions "buttons" from the `actions` array
//we have just one so its at index 0
[<#your alert#>.actions[0] setEnabled:NO];
}
else{
[<#your alert#>.actions[0] setEnabled:YES];
}
}
Don't forget to remove your observer when done
I wanted to extend the answer by Ryan Forsyth by adding this. If you add a Default styled UIAlertView, you can get an out of range exception if you try to access a textfield as none exist, so check your view style first.
-(BOOL)alertViewShouldEnableFirstOtherButton:(UIAlertView*)alertView
{
if(alertView.alertViewStyle == UIAlertViewStyleLoginAndPasswordInput ||
alertView.alertViewStyle == UIAlertViewStylePlainTextInput ||
alertView.alertViewStyle == UIAlertViewStyleSecureTextInput)
{
NSString* text = [[alertView textFieldAtIndex:0] text];
return ([text length] > 0);
}
else if (alertView.alertViewStyle == UIAlertViewStyleDefault)
return true;
else
return false;
}
You can create two buttons for Ok and Cancel.Then add those two as sub views in the UIAlertView.Now by checking the text(text length) in the textfield,You can perform enable and disable actions.
Without knowing the context of your application, the following may not apply - but have you read the iOS Human Interface Guidelines? It sounds as though you may be better off finding an alternative to UIAlertView if this is something that's going to be displayed to the user often.
Not really related to your question, but do not modify default UIAlertView if you don't want your app to be rejected. If I'm not wrong, you're adding textfields to the alertview, don't you? Like a login view. You should create your own view.
So, regarding your question, create your view, set the buttons has disabled, and delegate the UITextFields. When
- (void)textFieldDidBeginEditing:(UITextField *)textField;
is called, enable those buttons.
My app has several buttons which trigger different events. The user should NOT be able to hold down several buttons. Anyhow, holding down several buttons crashes the app.
And so, I'm trying to disable multi-touch in my app.
I've unchecked 'Multiple Touch' in all the xib files, and as far as I can work out, the properties 'multipleTouchEnabled' and 'exclusiveTouch' control whether the view uses multitouch. So in my applicationDidFinishLaunching I've put this:
self.mainViewController.view.multipleTouchEnabled = NO;
self.mainViewController.view.exclusiveTouch = YES;
And in each of my view controllers I've put this in the viewDidLoad
self.view.multipleTouchEnabled = NO;
self.view.exclusiveTouch = YES;
However, it still accepts multiple touches. I could do something like disable other buttons after getting a touch down event, but this would be an ugly hack. Surely there is a way to properly disable multi-touch?
If you want only one button to respond to touches at a time, you need to set exclusiveTouch for that button, rather than for the parent view. Alternatively, you could disable the other buttons when a button gets the "Touch Down" event.
Here's an example of the latter, which worked better in my testing. Setting exclusiveTouch for the buttons kind-of worked, but led to some interesting problems when you moved your finger off the edge of a button, rather than just clicking it.
You need to have outlets in your controller hooked up to each button, and have the "Touch Down", "Touch Up Inside", and "Touch Up Outside" events hooked to the proper methods in your controller.
#import "multibuttonsViewController.h"
#implementation multibuttonsViewController
// hook this up to "Touch Down" for each button
- (IBAction) pressed: (id) sender
{
if (sender == one)
{
two.enabled = false;
three.enabled = false;
[label setText: #"One"]; // or whatever you want to do
}
else if (sender == two)
{
one.enabled = false;
three.enabled = false;
[label setText: #"Two"]; // or whatever you want to do
}
else
{
one.enabled = false;
two.enabled = false;
[label setText: #"Three"]; // or whatever you want to do
}
}
// hook this up to "Touch Up Inside" and "Touch Up Outside"
- (IBAction) released: (id) sender
{
one.enabled = true;
two.enabled = true;
three.enabled = true;
}
#end
- (void)viewDidLoad {
[super viewDidLoad];
for(UIView* v in self.view.subviews)
{
if([v isKindOfClass:[UIButton class]])
{
UIButton* btn = (UIButton*)v;
[btn setExclusiveTouch:YES];
}
}
}
- (void)viewDidLoad {
[super viewDidLoad];
for(UIView* v in self.view.subviews)
{
if([v isKindOfClass:[UIButton class]])
{
UIButton* btn = (UIButton*)v;
[btn setExclusiveTouch:YES];
}
}
}
This code is tested and working perfectly for me.there is no app crash when pressing more than one button at a time.
Your app crashes for a reason. Investigate further, use the debugger, see what's wrong instead of trying to hide the bug.
Edit:
OK, ok, I have to admit I was a bit harsh. You have to set the exclusiveTouch property on each button. That's all. The multipleTouchEnabled property is irrelevant.
To disable multitouch in SWIFT:
You need first to have an outlet of every button and afterwards just set the exclusive touch to true.Therefore in you viewDidLoad() would have:
yourButton.exclusiveTouch = true.
// not really necessary but you could also add:
self.view.multipleTouchEnabled = false
If you want to disable multi touch throughout the application and don't want to write code for each button then you can simply use Appearance of button. Write below line in didFinishLaunchingWithOptions.
UIButton.appearance().isExclusiveTouch = true
Thats great!! UIAppearance
You can even use it for any of UIView class so if you want to disable multi touch for few buttons. Make a CustomClass of button and then
CustomButton.appearance().isExclusiveTouch = true
There is one more advantage which can help you. In case you want to disable multi touch of buttons in a particular ViewController
UIButton.appearance(whenContainedInInstancesOf: [ViewController2.self]).isExclusiveTouch = true
Based on neoevoke's answer, only improving it a bit so that it also checks subviews' children, I created this function and added it to my utils file:
// Set exclusive touch to all children
+ (void)setExclusiveTouchToChildrenOf:(NSArray *)subviews
{
for (UIView *v in subviews) {
[self setExclusiveTouchToChildrenOf:v.subviews];
if ([v isKindOfClass:[UIButton class]]) {
UIButton *btn = (UIButton *)v;
[btn setExclusiveTouch:YES];
}
}
}
Then, a simple call to:
[Utils setExclusiveTouchToChildrenOf:self.view.subviews];
... will do the trick.
This is quite often issue being reported by our testers. One of the approach that I'm using sometimes, although it should be used consciously, is to create category for UIView, like this one:
#implementation UIView (ExclusiveTouch)
- (BOOL)isExclusiveTouch
{
return YES;
}
Pretty much simple you can use make use of ExclusiveTouch property in this case
[youBtn setExclusiveTouch:YES];
This is a Boolean value that indicates whether the receiver handles touch events exclusively.
Setting this property to YES causes the receiver to block the delivery of touch events to other views in the same window. The default value of this property is NO.
For disabling global multitouch in Xamarin.iOS
Copy&Paste the code below:
[DllImport(ObjCRuntime.Constants.ObjectiveCLibrary, EntryPoint = "objc_msgSend")]
internal extern static IntPtr IntPtr_objc_msgSend(IntPtr receiver, IntPtr selector, bool isExclusiveTouch);
static void SetExclusiveTouch(bool isExclusiveTouch)
{
var selector = new ObjCRuntime.Selector("setExclusiveTouch:");
IntPtr_objc_msgSend(UIView.Appearance.Handle, selector.Handle, isExclusiveTouch);
}
And set it on AppDelegate:
public override bool FinishedLaunching(UIApplication app, NSDictionary options)
{
...
SetExclusiveTouch(true); // setting exlusive to true disables the multitouch
...
}
My experience is that, by default, a new project doesn't even allow multitouch, you have to turn it on. But I suppose that depends on how you got started. Did you use a mutlitouch example as a template?
First of all, are you absolutely sure multitouch is on? It's possible to generate single touches in sequence pretty quickly. Multitouch is more about what you do with two or more fingers once they are on the surface. Perhaps you have single touch on but aren't correctly dealing with what happens if two buttons are pressed at nearly the same time.
I've just had exactly this problem.
The solution we came up with was simply to inherit a new class from UIButton that overrides the initWithCoder method, and use that where we needed one button push at a time (ie. everywhere):
#implementation ExclusiveButton
(id)initWithCoder: (NSCoder*)decoder
{
[self setExclusiveTouch:YES];
return [super initWithCoder:decoder]
}
#end
Note that this only works with buttons loaded from nib files.
I created UIView Class Extension and added this two functions. and when i want to disable view touch i just call [view makeExclusiveTouch];
- (void) makeExclusiveTouchForViews:(NSArray*)views {
for (UIView * view in views) {
[view makeExclusiveTouch];
}
}
- (void) makeExclusiveTouch {
self.multipleTouchEnabled = NO;
self.exclusiveTouch = YES;
[self makeExclusiveTouchForViews:self.subviews];
}
If you want to disable multitouch programmatically, or if you are using cocos2d (no multipleTouchEnabled option), you can use the following code on your ccTouches delegate:
- (BOOL)ccTouchesBegan:(NSSet *)touches
withEvent:(UIEvent *)event {
NSSet *multiTouch = [event allTouches];
if( [multiTouch count] > 1) {
return;
}
else {
//else your rest of the code
}
Disable all the buttons on view in "Touch Down" event and enable them in "Touch Up Inside" event.
for example
- (void) handleTouchDown {
for (UIButton *btn in views) {
btn.enable = NO;
}
}
- (void) handleTouchUpInside {
for (UIButton *btn in views) {
btn.enable = Yes;
}
------
------
}
I decided this problem by this way:
NSTimeInterval intervalButtonPressed;
- (IBAction)buttonPicturePressed:(id)sender{
if (([[NSDate date] timeIntervalSince1970] - intervalButtonPressed) > 0.1f) {
intervalButtonPressed = [[NSDate date] timeIntervalSince1970];
//your code for button
}
}
I had struggled with some odd cases when dragging objects around a view, where if you touched another object at the same time it would fire the touchesBegan method. My work-around was to disable user interaction for the parent view until touchesEnded or touchesCancelled is called.
override func touchesMoved(touches: Set<UITouch>, withEvent event: UIEvent?) {
// whatever setup you need
self.view.userInteractionEnabled = false
}
override func touchesEnded(touches: Set<UITouch>, withEvent event: UIEvent?) {
// whatever setup you need
self.view.userInteractionEnabled = true
}
override func touchesCancelled(touches: Set<UITouch>?, withEvent event: UIEvent?) {
// whatever setup you need
self.view.userInteractionEnabled = true
}
A Gotcha:
If you are using isExclusiveTouch, be aware that overriding point(inside:) on the button can interfere, effectively making isExclusiveTouch useless.
(Sometimes you need to override point(inside:) for handling the "button not responsive at bottom of iPhone screen" bug/misfeature (which is caused by Apple installing swipe GestureRecognizers at the bottom of the screen, interfering with button highlighting.)
See: UIButton fails to properly register touch in bottom region of iPhone screen
Just set all relevant UIView's property exclusiveTouch to false do the trick.