How do I detect a tap anywhere in the view? - iphone

I have a tutorial for my app, which should display only the first time the app is opened and should be tapped to dismiss.
I am initializing a UITapGestureRecognizer in my viewDidLoad:
tapper_tut = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleSingleTap:)];
tapper_tut.cancelsTouchesInView = FALSE;
[self.view addGestureRecognizer:tapper_tut];
and I have an IBAction to detect the tap and set the tutorial to hidden:
- (IBAction)dismiss_tut{
if (????????????????) {
_tutorial.hidden = YES;
}
}
But I have no idea what to put in the if statement condition, or if this is even that right way to go about this.
How would I dismiss a UIImageView on a tap?

UITapGestureRecognizer *gr = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleGesture:)];
[self.view addGestureRecognizer:gr];
// if not using ARC, you should [gr release];
// mySensitiveRect coords are in the coordinate system of self.view
- (void)handleGesture:(UIGestureRecognizer *)gestureRecognizer {
CGPoint p = [gestureRecognizer locationInView:self.view];
if (CGRectContainsPoint(mySensitiveRect, p)) {
NSLog(#"got a tap in the region i care about");
} else {
NSLog(#"got a tap, but not where i need it");
}
}

You can make viewDidLoad like this
- (void)viewDidLoad
{
[super viewDidLoad];
self.view.backgroundColor = [UIColor whiteColor];
/* Create the Tap Gesture Recognizer */
self.tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self
action:#selector(handleTaps:)];
/* The number of fingers that must be on the screen */
self.tapGestureRecognizer.numberOfTouchesRequired = 1;
/* The total number of taps to be performed before the gesture is recognized */
self.tapGestureRecognizer.numberOfTapsRequired = 1;
/* Add this gesture recognizer to the view */
[self.view addGestureRecognizer:self.tapGestureRecognizer];
}
To detect the taps you can make the method like this.
- (void) handleTaps:(UITapGestureRecognizer*)paramSender
{
NSUInteger touchCounter = 0;
for (touchCounter = 0;touchCounter < paramSender.numberOfTouchesRequired;touchCounter++)
{
CGPoint touchPoint =[paramSender locationOfTouch:touchCounter inView:paramSender.view];
NSLog(#"Touch #%lu: %#",(unsigned long)touchCounter+1, NSStringFromCGPoint(touchPoint));
}
}

you have to declare .h file as "UIGestureRecognizerDelegate"
you have getting tap of gesture as two way as given below steps.
1) Call delegate method of GestureRecognizer (not given action )
UITapGestureRecognizer *recognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:nil]; // not given action.
recognizer.numberOfTouchesRequired=1;// here how many tap you want set it
[self.view addGestureRecognizer:recognizer];
recognizer.delegate = self;
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
//whatever you want write code here
return NO;
}
2) given action
UITapGestureRecognizer *oneTouch=[[UITapGestureRecognizer alloc]initWithTarget:self action:#selector(Addphoto)];
[oneTouch setNumberOfTouchesRequired:1];
[self.view addGestureRecognizer:oneTouch];
-(IBAction)Addphoto
{
//whatever you want write code here
}
may be it will help .

I think u need to detect the first time launch of the application which u can do with following
![[NSUserDefaults standardUserDefaults] boolForKey:#"HasLaunchedOnce"]
Put this in your if statement .

Related

Touch count detect and perform function

tapGesture = [[UITapGestureRecognizer alloc] initWithTarget:self
action:#selector(handleTapGesture:)];
tapGesture.numberOfTapsRequired = 2;
tapGesture.numberOfTouchesRequired = 1;
[self.view addGestureRecognizer:tapGesture];
[tapGesture release];
and
- (void)handleTapGesture:(UITapGestureRecognizer *)sender {
if (sender.state == UIGestureRecognizerStateRecognized) {
// handling code
NSLog(#"We got double tap here");
DashBoardViewController* dashboardObj = [[DashBoardViewController alloc] initWithNibName:#"DashBoardViewController" bundle:nil];
[self.navigationController pushViewController:dashboardObj animated:YES];
}
what i am trying to do is , i want to call 2 different events on single tap and on double tap.
So how can i detect when tap==1 and tap==2?
Double tap is recognised in my code, but i am not sure, how to find and work,when a single tap is find.
Thanks
This may give u a soln
UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleSingleTap:)];
UITapGestureRecognizer *doubleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleDoubleTap:)];
[doubleTap setNumberOfTapsRequired:2];
[singleTap setNumberOfTouchesRequired:1];
[self.view addGestureRecognizer:singleTap];
[self.view addGestureRecognizer:doubleTap];
- (void)handleSingleTap:(UIGestureRecognizer *)gestureRecognizer {
// single tap action
}
- (void)handleDoubleTap:(UIGestureRecognizer *)gestureRecognizer {
// double tap action
}
or u have to use NSTimer as darren pointed to validate the single touch.
In the method,
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
Following seems to a good post about touch in iOS.
http://www.sitepen.com/blog/2008/07/10/touching-and-gesturing-on-the-iphone/

UIGestureRecognizer across entire view

I want to be able to make a gesture recognizer listening for a two finger swipe, anywhere on the screen.
Right now I have a UITableView in a sub-view that scrolls, of course, and it doesn't seem to pick up the UIGestureRecognizer that I set on the view. When you use the two fingers, it just scrolls...
Is there a way to make the entire view, maybe superview, listen for a two finger touch and when it recognizes it, it will instead of scrolling the table view, do what I want it to do?
EDIT: Heres my code but this is suposed to be a very general question. I just want to be able to have UIGestureRecognizers across the entire view, the whole thing.
navBarTitle.title = #"Crunch";
//opening the menuView from launch
//setup the customtable view as a subview in menuView
SDMenuViewController *mvc = [[[SDMenuViewController alloc] initWithNibName:#"SDNestedTableView" bundle:nil] autorelease];
[self addChildViewController:mvc];
[mvc didMoveToParentViewController:self];
[menuView addSubview:mvc.view];
[mvc.view setFrame:CGRectMake(mvc.view.frame.origin.x, mvc.view.frame.origin.y, mvc.view.frame.size.width, mvc.view.frame.size.height + 44)]; //add navBarHeight, for some strage reason
//add swipe down gesture on for the menu
UISwipeGestureRecognizer *swipeClose =[[[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(closeMenu)] autorelease];
swipeClose.numberOfTouchesRequired = 2;
swipeClose.direction = UISwipeGestureRecognizerDirectionUp;
UISwipeGestureRecognizer *swipeOpen = [[[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(openMenu)] autorelease];
swipeOpen.numberOfTouchesRequired = 2;
swipeOpen.direction = UISwipeGestureRecognizerDirectionDown;
for (UIGestureRecognizer* rec in menuView.gestureRecognizers) {
[rec requireGestureRecognizerToFail:swipeClose];
[rec requireGestureRecognizerToFail:swipeOpen];
}
for (UIGestureRecognizer* rec in mvc.view.gestureRecognizers) {
[rec requireGestureRecognizerToFail:swipeClose];
[rec requireGestureRecognizerToFail:swipeOpen];
}
[mvc.view addGestureRecognizer:swipeClose];
[mvc.view addGestureRecognizer:swipeOpen];
[self.view addGestureRecognizer:swipeClose];
[self.view addGestureRecognizer:swipeOpen];
Maybe I did not explain my question clearly. But for what I was doing this ended up working, and maybe it will help other people in the future:
Two finger swipe in UIScrollview for iPad application
you can try to do something like this:
UISwipeGestureRecognizer* p = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(actionPan:)];
p.numberOfTouchesRequired = 2;
for (UIGestureRecognizer* rec in tableView.gestureRecognizers) {
[rec requireGestureRecognizerToFail:p];
}
[self.view addGestureRecognizer:p];
hope that will help
//In view did load
[self.view setMultipleTouchEnabled:YES];
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
if ([[event touchesForView:self.view] count] > 1) {
NSLog(#"%d active touches",[[event touchesForView:self.view] count]) ;
UISwipeGestureRecognizer *swipeGesture = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleSwipeGesture:)];
swipeGesture.direction = UISwipeGestureRecognizerDirectionUp;
[self.view addGestureRecognizer:swipeGesture];
}
}
-(void)handleSwipeGesture:(UISwipeGestureRecognizer *) sender
{
//Gesture detect - swipe up/down , can be recognized direction
if(sender.direction == UISwipeGestureRecognizerDirectionUp)
{
// do some thing...
}
}
i Hope this would solve your problem. and in touches enabled make the count equal to 2 or any number of touches.. :) feel free to ask if you have any doubts
  Add another view with frame of self.view over self.view like "viewForGesture" and add gesture recognizer on that view like
UIView *viewForGesture = [[ [UIView alloc]initWithFrame:self.view.frame] autorelease];
[viewForGesture setBackgroundColor:[UIColor clearColor]];
[self.view addSubview:viewForGesture];
.
.
.
[viewForGesture addGestureRecognizer:swipeOpen];
[viewForGesture addGestureRecognizer:swipeClose];
There's two way of making UIView detecting touch. The approach you defined and want that's UIGestureRecognizer, that answer already given by Ezeki.
Another approach you can use to detect touch is to override UITouch delegates.
- (void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = [touches anyObject];
if(touch.tapCount==2)
{
//Do something ... (Here, you can also check for the object which touched.)
}
}

Detect when user taps the selection indicator in a UIDatePicker?

How can I detect when the user taps the selection indicator in a UIDatePicker?
Without this the user has to scroll to some other date and then back again to pick the date which is displayed under the selection indicator when the date picker slides up.
Thanks a lot,
Stine
UPDATE: This is the only solution I could come up with myself:
UIDatePicker *aDatePicker = [[UIDatePicker alloc] init];
self.datePicker = aDatePicker;
[aDatePicker release];
[self.datePicker addTarget:self action:#selector(datePicked:) forControlEvents:UIControlEventValueChanged];
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(datePicked:)];
[self.datePicker addGestureRecognizer:tap];
[tap release];
Which means that datePicked will be called twice when the user actually rotates the wheel.
UPDATE: The above mentioned solution does not work for UIPickerViews though. I do not know how to achieve the wanted behavior in those cases.
You can do some tweak in this way:-
Conform delegate <UIGestureRecognizerDelegate>in your .h file
UITapGestureRecognizer* gestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(pickerViewTapGestureRecognized:)];
[yourDatePicker addGestureRecognizer:gestureRecognizer];
gestureRecognizer.delegate=self;
gestureRecognizer.numberOfTapsRequired=2;//Whenever you do double tap it will called. So allow user to do double tap on selected date.
//Below is the Delegate method
-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
return YES;
}
//Below method will trigger when do the double tap
-(void)pickerViewTapGestureRecognized:(UITapGestureRecognizer*)recognizer
{
UIDatePicker *datePicker=(UIDatePicker*)[[recognizer view] viewWithTag:101];
NSLog(#"datePicker=%#", datePicker.date);
}
Try this code:
UITapGestureRecognizer *recognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(pickerViewTapped:)];
[recognizer setNumberOfTapsRequired:2];
[recognizer setCancelsTouchesInView:NO];
[recognizer setDelaysTouchesEnded:NO];
[recognizer setDelaysTouchesBegan:NO];
[self.answerPicker addGestureRecognizer:recognizer];
// ....
- (IBAction)pickerViewTapped:(UITapGestureRecognizer *)sender {
CGPoint coord = [sender locationInView:self.answerPicker];
if(coord.y <= 126 && coord.y >= 90) {
//do something
}
}
This is an old question but here's what I did in order to grab the selection bar rect on the UIDatePicker. With this, you could just add a button/view with a gesture recognizer to detect taps. It's a bit of a hack but it seems to be working well in iOS6 and iOS7.
+ (CGRect)getSelectionBarRectFromPicker:(UIDatePicker *)picker
{
int counter = 0;
CGRect selectionBarRect;
for(UIView *datePickerView in picker.subviews){
for(UIView *subview in datePickerView.subviews){
if([[[UIDevice currentDevice] systemVersion] floatValue] < 7.0){
if([NSStringFromClass([subview class]) isEqualToString:#"_UIPickerViewSelectionBar"]){
if(counter == 0){
selectionBarRect.origin = subview.frame.origin;
selectionBarRect.size.height = subview.frame.size.height;
}
selectionBarRect.size.width += subview.frame.size.width;
counter++;
}
} else {
if(subview.frame.size.height < 1){
if(counter == 0){
selectionBarRect.origin = subview.frame.origin;
selectionBarRect.size.width = subview.frame.size.width;
} else {
selectionBarRect.size.height = subview.frame.origin.y - selectionBarRect.origin.y;
}
counter++;
}
}
}
}
return selectionBarRect;
}

Objective-c: How to detect double tap on view?

I am developing an application where I have multiple controls on view but I want to enable them when user double tap the view
You can take the example of double click but in device I want to catch the event when their is double tap.
You need to add an UITapGestureRecognizer to the view which you want to be tapped.
Like this:
- (void)viewDidLoad {
[super viewDidLoad];
UITapGestureRecognizer *tapGesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleTapGesture:)];
tapGesture.numberOfTapsRequired = 2;
[self.view addGestureRecognizer:tapGesture];
[tapGesture release];
}
- (void)handleTapGesture:(UITapGestureRecognizer *)sender {
if (sender.state == UIGestureRecognizerStateRecognized) {
// handling code
}
}
Add a UITapGestureRecognizer to the view, with numberOfTapsRequired = 2.

Limit tap gesture to scrollview and not the button placed upon it

I have a scroll view and a button placed over it , When i add a tap gesture recognizer the button does not work. Is there any way of limiting the tap only to scroll view and not to the button, so that the button functions normally.
here is my code
UITapGestureRecognizer* tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(tapGesture:)];
tap.numberOfTapsRequired = 1;
tap.numberOfTouchesRequired = 1;
[scroll addGestureRecognizer:tap];
[tap release];
- (void)tapGesture:(UIGestureRecognizer*)gesture{
NSLog(#"scroll tapped");
}
If you do
tap.cancelsTouchesInView = NO;
It will allow button to be pressed. However taps will be detected along with the button press when you press a button. Do avoid this, you will have to subclass UIScrollView and implement the following method –
- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event {
for ( UIView * subview in self.subviews ) {
UIView * hitView = [subview hitTest:point withEvent:event];
if ( hitView )
return hitView;
}
return [super hitTest:point withEvent:event];
}
Implementing the method above pass the touches to the scroll view's subviews.
There is no need to subclass Scrollview. Following code solves the problem easy way. The method gestureRecognizer:shouldReceiveTouch: does the trick.
UITapGestureRecognizer* tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(tapGesture:)];
tap.numberOfTapsRequired = 1;
tap.numberOfTouchesRequired = 1;
tap.delegate = self;
tap.cancelsTouchesInView = NO;
[scroll addGestureRecognizer:tap];
[tap release];
-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
if (scroll.superview != nil) {
if ([touch.view isKindOfClass:[UIButton class]])
{
return NO; // ignore the touch
}
}
return YES; // handle the touch
}
- (void)tapGesture:(UIGestureRecognizer*)gesture {
NSLog(#"scroll tapped");
}