Using the GestureRecognizer attached to a view triggers my app to crash with EXC_BAD_ACCESS error. Here's the classes involved
• BoardViewController - Displaying a board (as background) set as rootViewController in the AppDelegate. It instantiates multiple objects of the "TaskViewcontroller".
//BoardViewController.h
#interface BoardViewController : UIViewController {
NSMutableArray* allTaskViews; //for storing taskViews to avoid having them autoreleased
}
//BoardViewController.m - Rootviewcontroller, instantiating TaskViews
- (void)viewDidLoad
{
[super viewDidLoad];
TaskViewController* taskA = [[TaskViewController alloc]init];
[allTaskViews addObject:taskA];
[[self view]addSubview:[taskA view]];
}
• TaskViewController - An indivual box displayed on the board. It should be draggable. Therefore I attached UIPanGestureRecoginzer to its view
- (void)viewDidLoad
{
[super viewDidLoad];
UIPanGestureRecognizer* panRecognizer = [[UIPanGestureRecognizer alloc]initWithTarget:self action:#selector(handlePan:)];
[[self view] addGestureRecognizer:panRecognizer];
}
- (void)handlePan:(UIPanGestureRecognizer *)recognizer {
NSLog(#"PAN!");
}
The .xib file is a simple view.
All programming with the gesture recognizer I'd prefer to do in code. Any idea how to fix the error causing the app crash?
The method handlePan is on your view controller, not on your view. You should set the target to self:
UIPanGestureRecognizer* panRecognizer = [[UIPanGestureRecognizer alloc]initWithTarget:self action:#selector(handlePan:)];
EDIT (in response to the edit of the question) As omz has correctly noted, your TaskViewController gets released upon BoardViewController's viewDidLoad: exit. There are two ways of dealing with it:
Fold the handlePan method into the parent view controller, along with the code of viewDidLoad:, or
Make an instance variable for TaskViewController *taskA, rather than making it a local variable.
This is my way to use Gesture Recognizer. I think this way is easy and with low risk.
At first, you drag and drop Gesture Recognizer into the view.
Then, you wire the Gesture Recognizer icon to code.
Finally, you write code for this IBAction like below:
- (IBAction)handlePan:(id)sender {
NSLog(#"PAN!");
}
You can download this project from GitHub and just run it.
https://github.com/weed/p120812_PanGesture
I have two windows, my main window "window" and "help window" all inside my App Delegate. In my main window its view is subclassed and I want to draw a rect inside it. My help window has a rect also but it has an NSTracker on it. What I want to do is draw my rect in my window subclass with the x and y coordinates equal to my NSTracker position. The problem I am having is it crashes when I try to bring in the coordinates, any ideas of what I could be doing wrong? thanks
//My subclass of window is called CutoutView. This is all in draw rect
AppDelegate *controller = [[[NSApp delegate] window] contentView];
xValue = controller.mouseLoc.x;
yValue = controller.mouseLoc.y;
NSRectFillUsingOperation(NSMakeRect(xValue,yValue, 600, 400), NSCompositeClear);
[self update];
- (void)update
{
NSLog(#"test");
[self setNeedsDisplay:YES];
}
//My AppDelegate with the tracker helpView is a reference to the view of my second window "Help Window"
-(void)updateTrackingAreas
{
if(trackingArea != nil) {
[self.helpView removeTrackingArea:trackingArea];
[trackingArea release];
}
opts = (NSTrackingActiveAlways | NSTrackingMouseEnteredAndExited | NSTrackingMouseMoved);
trackingArea = [ [NSTrackingArea alloc] initWithRect:[self.helpView bounds]
options:opts
owner:self
userInfo:nil];
[self.helpView addTrackingArea:trackingArea];
}
-(void)mouseMoved:(NSEvent *)theEvent
{
mouseLoc = [NSEvent mouseLocation];
NSLog(#"mouseMoved: %f %f", mouseLoc.x, mouseLoc.y);
}
in my CutoutView am i getting the AppController wrong because it is in a different window "helpWindow"? or does it have to do with my int values?
There are many things wrong with your code and it's obvious that you are fundamentally misunderstanding some basic concepts.
Firstly, you state that this code is in your drawRect: method;
AppDelegate *controller = [[[NSApp delegate] window] contentView];
xValue = controller.mouseLoc.x;
yValue = controller.mouseLoc.y;
NSRectFillUsingOperation(NSMakeRect(xValue,yValue, 600, 400), NSCompositeClear);
[self update];
There are several immediate flaws apparent. Firstly, why are you declaring controller to be of type AppController* when the method you are calling (-contentView) returns an NSView?
Your AppController is not a view (at least it should not be!), so you should be declaring the object as such:
NSView* mainView = [[[NSApp delegate] window] contentView];
If you are indeed using a view as a controller then this is completely wrong. See below for my note about MVC.
You don't specify where the mouseLoc property is coming from. We need to see where this is declared, because that will affect whether or not there are problems with it.
Your drawing code calls [self update], which simply tells the view to redraw itself. This will result in an infinite loop because every time the view draws it is forced to redraw. You should never call setNeedsDisplay: from inside drawRect:.
Even after making these changes, this code is very badly structured and the design is broken.
As it stands, your code violates the Model-View-Controller pattern. A views should not have knowledge of other views. You need to restructure things so that your views display properties of your controller without needing knowledge of other views. That means that you must store the mouse location in your controller (or a model object) and use some method for the view to access that information, preferably a datasource protocol or similar. In my answer to this other question I give an example of how to do that.
You need to read the Cocoa Drawing Guide. You also need to learn more core Cocoa concepts as it is clear you are misunderstanding how Cocoa is supposed to work.
I have quite a few controls scattered throughout many table cells in my table, and I was wondering if there's an easier way to dismiss the keyboard without having to loop through all my controls and resigning them all as the first responder. I guess the question is.. How would I get the current first responder to the keyboard?
Try:
[self.view endEditing:YES];
You can force the currently-editing view to resign its first responder status with [view endEditing:YES]. This hides the keyboard.
Unlike -[UIResponder resignFirstResponder], -[UIView endEditing:] will search through subviews to find the current first responder. So you can send it to your top-level view (e.g. self.view in a UIViewController) and it will do the right thing.
(This answer previously included a couple of other solutions, which also worked but were more complicated than is necessary. I've removed them to avoid confusion.)
You can send a nil targeted action to the application, it'll resign first responder at any time without having to worry about which view currently has first responder status.
Objective-C:
[[UIApplication sharedApplication] sendAction:#selector(resignFirstResponder) to:nil from:nil forEvent:nil];
Swift 3.0:
UIApplication.shared.sendAction(#selector(resignFirstResponder), to: nil, from: nil, for: nil)
Nil targeted actions are common on Mac OS X for menu commands, and here's a use for them on iOS.
To be honest, I'm not crazy about any of the solutions proposed here. I did find a nice way to use a TapGestureRecognizer that I think gets to the heart of your problem: When you click on anything besides the keyboard, dismiss the keyboard.
In viewDidLoad, register to receive keyboard notifications and create a UITapGestureRecognizer:
NSNotificationCenter *nc = [NSNotificationCenter defaultCenter];
[nc addObserver:self selector:#selector(keyboardWillShow:) name:
UIKeyboardWillShowNotification object:nil];
[nc addObserver:self selector:#selector(keyboardWillHide:) name:
UIKeyboardWillHideNotification object:nil];
tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self
action:#selector(didTapAnywhere:)];
Add the keyboard show/hide responders. There you add and remove the TapGestureRecognizer to the UIView that should dismiss the keyboard when tapped. Note: You do not have to add it to all of the sub-views or controls.
-(void) keyboardWillShow:(NSNotification *) note {
[self.view addGestureRecognizer:tapRecognizer];
}
-(void) keyboardWillHide:(NSNotification *) note
{
[self.view removeGestureRecognizer:tapRecognizer];
}
The TapGestureRecognizer will call your function when it gets a tap and you can dismiss the keyboard like this:
-(void)didTapAnywhere: (UITapGestureRecognizer*) recognizer {
[textField resignFirstResponder];
}
The nice thing about this solution is that it only filters for Taps, not swipes. So if you have scrolling content above the keyboard, swipes will still scroll and leave the keyboard displayed. By removing the gesture recognizer after the keyboard is gone, future taps on your view get handled normally.
This is a solution to make the keyboard go away when hit return in any textfield, by adding code in one place (so don't have to add a handler for each textfield):
consider this scenario:
i have a viewcontroller with two textfields (username and password).
and the viewcontroller implements UITextFieldDelegate protocol
i do this in viewDidLoad
- (void)viewDidLoad
{
[super viewDidLoad];
username.delegate = self;
password.delegate = self;
}
and the viewcontroller implements the optional method as
- (BOOL)textFieldShouldReturn:(UITextField *)textField
{
[textField resignFirstResponder];
return YES;
}
and irrespective of the textfield you are in, as soon as i hit return in the keyboard, it gets dismissed!
In your case, the same would work as long as you set all the textfield's delegate to self and implement textFieldShouldReturn
A better approach is to have something "steal" first responder status.
Since UIApplication is a subclass of UIResponder, you could try:
[[UIApplication sharedApplication] becomeFirstResponder]
[[UIApplication sharedApplication] resignFirstResponder]
Failing that, create a new UITextField with a zero sized frame, add it to a view somewhere and do something similar (become followed by resign).
Tuck this away in some utility class.
+ (void)dismissKeyboard {
[self globalResignFirstResponder];
}
+ (void) globalResignFirstResponder {
UIWindow * window = [[UIApplication sharedApplication] keyWindow];
for (UIView * view in [window subviews]){
[self globalResignFirstResponderRec:view];
}
}
+ (void) globalResignFirstResponderRec:(UIView*) view {
if ([view respondsToSelector:#selector(resignFirstResponder)]){
[view resignFirstResponder];
}
for (UIView * subview in [view subviews]){
[self globalResignFirstResponderRec:subview];
}
}
#Nicholas Riley & #Kendall Helmstetter Geln & #cannyboy:
Absolutely brilliant!
Thank you.
Considering your advice and the advice of others in this thread, this is what I've done:
What it looks like when used:
[[self appDelegate] dismissKeyboard]; (note: I added appDelegate as an addition to NSObject so I can use anywhere on anything)
What it looks like under the hood:
- (void)dismissKeyboard
{
UITextField *tempTextField = [[[UITextField alloc] initWithFrame:CGRectZero] autorelease];
tempTextField.enabled = NO;
[myRootViewController.view addSubview:tempTextField];
[tempTextField becomeFirstResponder];
[tempTextField resignFirstResponder];
[tempTextField removeFromSuperview];
}
EDIT
Amendment to my answer to included tempTextField.enabled = NO;. Disabling the text field will prevent UIKeyboardWillShowNotification and UIKeyboardWillHideNotification keyboard notifications from being sent should you rely on these notifications throughout your app.
Quick tip on how to dismiss the keyboard in iOS when a user touches anywhere on the screen outside of the UITextField or keyboard. Considering how much real estate the iOS keyboard can take up, it makes sense to have an easy and intuitive way for your users to dismiss the keyboard.
Here's a link
A lot of overly-complicated answers here, perhaps because this is not easy to find in the iOS documentation. JosephH had it right above:
[[view window] endEditing:YES];
Here's what I use in my code. It works like a charm!
In yourviewcontroller.h add:
#property (nonatomic) UITapGestureRecognizer *tapRecognizer;
Now in the .m file, add this to your ViewDidLoad function:
- (void)viewDidLoad {
//Keyboard stuff
tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(didTapAnywhere:)];
tapRecognizer.cancelsTouchesInView = NO;
[self.view addGestureRecognizer:tapRecognizer];
}
Also, add this function in the .m file:
- (void)handleSingleTap:(UITapGestureRecognizer *) sender
{
[self.view endEditing:YES];
}
Even Simpler than Meagar's answer
overwrite touchesBegan:withEvent:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
[textField resignFirstResponder];`
}
This will dismiss the keyboardwhen you touch anywhere in the background.
You should send endEditing: to working window being the subclass of UIView
[[UIApplication sharedApplication].windows.firstObject endEditing:NO];
In your view controller's header file add <UITextFieldDelegate> to the definition of your controller's interface so that it conform to the UITextField delegate protocol...
#interface someViewController : UIViewController <UITextFieldDelegate>
... In the controller's implementation file (.m) add the following method, or the code inside it if you already have a viewDidLoad method ...
- (void)viewDidLoad
{
// Do any additional setup after loading the view, typically from a nib.
self.yourTextBox.delegate = self;
}
... Then, link yourTextBox to your actual text field
- (BOOL)textFieldShouldReturn:(UITextField *)theTextField
{
if (theTextField == yourTextBox) {
[theTextField resignFirstResponder];
}
return YES;
}
The best way to dismiss keyboard from UITableView and UIScrollView are:
tableView.keyboardDismissMode = UIScrollViewKeyboardDismissModeOnDrag
In swift 3 you can do the following
UIApplication.shared.sendAction(#selector(UIResponder.resignFirstResponder), to: nil, from: nil, for: nil)
Jeremy's answer wasn't quite working for me, I think because I had a navigation stack in a tab view with a modal dialog on top of it. I'm using the following right now and it is working for me, but your mileage may vary.
// dismiss keyboard (mostly macro)
[[UIApplication sharedApplication].delegate dismissKeyboard]; // call this in your to app dismiss the keybaord
// --- dismiss keyboard (in indexAppDelegate.h) (mostly macro)
- (void)dismissKeyboard;
// --- dismiss keyboard (in indexAppDelegate.m) (mostly macro)
// do this from anywhere to dismiss the keybard
- (void)dismissKeyboard { // from: http://stackoverflow.com/questions/741185/easy-way-to-dismiss-keyboard
UITextField *tempTextField = [[UITextField alloc] initWithFrame:CGRectZero];
UIViewController *myRootViewController = <#viewController#>; // for simple apps (INPUT: viewController is whatever your root controller is called. Probably is a way to determine this progragrammatically)
UIViewController *uivc;
if (myRootViewController.navigationController != nil) { // for when there is a nav stack
uivc = myRootViewController.navigationController;
} else {
uivc = myRootViewController;
}
if (uivc.modalViewController != nil) { // for when there is something modal
uivc = uivc.modalViewController;
}
[uivc.view addSubview:tempTextField];
[tempTextField becomeFirstResponder];
[tempTextField resignFirstResponder];
[tempTextField removeFromSuperview];
[tempTextField release];
}
You may also need to override UIViewController disablesAutomaticKeyboardDismissal to get this to work in some cases. This may have to be done on the UINavigationController if you have one.
Subclass your textfields... and also textviews
In the subclass put this code..
-(void)conformsToKeyboardDismissNotification{
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(dismissKeyBoard) name:KEYBOARD_DISMISS object:nil];
}
-(void)deConformsToKeyboardDismissNotification{
[[NSNotificationCenter defaultCenter] removeObserver:self name:KEYBOARD_DISMISS object:nil];
}
- (void)dealloc{
[[NSNotificationCenter defaultCenter] removeObserver:self];
[self resignFirstResponder];
}
In the textfield delegates (similarly for textview delegates)
-(void)textFieldDidBeginEditing:(JCPTextField *)textField{
[textField conformsToKeyboardDismissNotification];
}
- (void)textFieldDidEndEditing:(JCPTextField *)textField{
[textField deConformsToKeyboardDismissNotification];
}
All set.. Now just post the notification from anywhere in your code. It will resign any keyboard.
And in swift we can do
UIApplication.sharedApplication().sendAction("resignFirstResponder", to: nil, from: nil, forEvent: nil)
To dismiss a keyboard after the keyboard has popped up, there are 2 cases,
when the UITextField is inside a UIScrollView
when the UITextField is outside a UIScrollView
2.when the UITextField is outside a UIScrollView
override the method in your UIViewController subclass
you must also add delegate for all UITextView
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
[self.view endEditing:YES];
}
In a scroll view, Tapping outside will not fire any event, so in that case use a Tap Gesture Recognizer,
Drag and drop a UITapGesture for the scroll view and create an IBAction for it.
to create a IBAction, press ctrl+ click the UITapGesture and drag it to the .h file of viewcontroller.
Here I have named tappedEvent as my action name
- (IBAction)tappedEvent:(id)sender {
[self.view endEditing:YES]; }
the abouve given Information was derived from the following link, please refer for more information or contact me if you dont understand the abouve data.
http://samwize.com/2014/03/27/dismiss-keyboard-when-tap-outside-a-uitextfield-slash-uitextview/
I hate that there's no "global" way to programmatically dismiss the keyboard without using private API calls. Frequently, I have the need to dismiss the keyboard programmatically without knowing what object is the first responder. I've resorted to inspecting the self using the Objective-C runtime API, enumerating through all of its properties, pulling out those which are of type UITextField, and sending them the resignFirstResponder message.
It shouldn't be this hard to do this...
It's not pretty, but the way I resign the firstResponder when I don't know what that the responder is:
Create an UITextField, either in IB or programmatically. Make it Hidden. Link it up to your code if you made it in IB.
Then, when you want to dismiss the keyboard, you switch the responder to the invisible text field, and immediately resign it:
[self.invisibleField becomeFirstResponder];
[self.invisibleField resignFirstResponder];
You can recursively iterate through subviews, store an array of all UITextFields, and then loop through them and resign them all.
Not really a great solution, especially if you have a lot of subviews, but for simple apps it should do the trick.
I solved this in a much more complicated, but much more performant way, but using a singleton/manager for the animation engine of my app, and any time a text field became the responder, I would assign assign it to a static which would get swept up (resigned) based on certain other events... its almost impossible for me to explain in a paragraph.
Be creative, it only took me 10 minutes to think through this for my app after I found this question.
A slightly more robust method I needed to use recently:
- (void) dismissKeyboard {
NSArray *windows = [UIApplication sharedApplication].windows;
for(UIWindow *window in windows) [window endEditing:true];
// Or if you're only working with one UIWindow:
[[UIApplication sharedApplication].keyWindow endEditing:true];
}
I found some of the other "global" methods didn't work (for example, UIWebView & WKWebView refused to resign).
Add A Tap Gesture Recognizer to your view.And define it ibaction
your .m file will be like
- (IBAction)hideKeyboardGesture:(id)sender {
NSArray *windows = [UIApplication sharedApplication].windows;
for(UIWindow *window in windows) [window endEditing:true];
[[UIApplication sharedApplication].keyWindow endEditing:true];
}
It's worked for me
Yes, endEditing is the best option. And From iOW 7.0, UIScrollView has a cool feature to dismiss the keyboard on interacting with the scroll view. For achieving this, you can set keyboardDismissMode property of UIScrollView.
Set the keyboard dismiss mode as:
tableView.keyboardDismissMode = UIScrollViewKeyboardDismissModeOnDrag
It has few other types. Have a look at this apple document.
In swift :
self.view.endEditing(true)
the easist way is to call the method
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
if(![txtfld resignFirstResponder])
{
[txtfld resignFirstResponder];
}
else
{
}
[super touchesBegan:touches withEvent:event];
}
You have to use one of these methods,
[self.view endEditing:YES];
or
[self.textField resignFirstResponder];