I have a subview, and part of the view is transparent, so to the user, if they were to touch in that transparent space then whatever is visible (but also underneath it) should be interactive.
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
CGPoint pt = [[touches anyObject] locationInView:self];
if (CGRectContainsPoint(tableViewUse.frame, pt)){
[self becomeFirstResponder];
}else {
[super becomeFirstResponder];
}
}
I have the above code in my subview class, but the problem is that the [super becomeFirstResponder] call is not working. Now the obvious solution is to have a [self resignFirstResponder] call in the class of my superview; however, I plan to use many instances of this class in my code, so I would have to find the touch and compare it against the frame of each of my instances etc. So the elegant solution is to control everything from the subview.
Thank you for any help!
P.s just noticed a problem that will change my question. If I were to make the superview become the first responder, then any touchesBegan method will be called in that superview and the touch will have to be managed there. eeeeeek.
Tried this
[self.superview becomeFirstResponder]; ?
Related
Note: I already read some questions about the UIScrollView sending touches to the subviews (this included and although I have up voted, it's not working as I intended anymore).
What I have: I have a UIScrollView with a Custom UIView (let's call it A) inside which covers the entire UIScrollView. I am also allowed to put other custom UIViews inside the A.
On the code I am doing this:
[scrollView setDelaysContentTouches:YES];
scrollView.canCancelContentTouches = NO;
What is happening: At the moment my only issue is that, if I want to move a subview inside A, I have to touch it, wait, and then move it. Exactly as stated here:
Now, the behaviour changes depending on the "length in time" of the
first touch on the UIView. If it's short, then the relative dragging
is managed as it was a scroll for the UIScrollView. If it's long, then
I'm getting the touchesMoved: events inside my UIView.
What I want: The subviews inside A should always receive priority and I shouldn't have to touch and wait. If I touch A and not a subview of it, I want the UIScrollView to receive the touches, like panning and moving around (the contentSize is bigger than the frame).
Edit 1.0
The only reason for me to have this A view inside a generic UIScrollView, is because I want to be able to zoom in/out on the A view. So I am doing the following:
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView {
return customView; // this is the A view
}
In the beginning I didn't had the A view inside the UIScrollView and the only thing I did was adding the A as a subView of my UIViewController's root view and everything went well. If there is another way to enable zoom in/out I will gladly accept the answer.
Note: Thank you all for your contributions, specially to Aaron Hayman.
I was able to figure it out by doing the following on the UIScrollView sub-class I had:
-(BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
CGPoint pointOfContact = [gestureRecognizer locationInView:self];
// The view with a tag of 200 is my A view.
return (![[self hitTest:pointOfContact withEvent:nil] isEqual:[self viewWithTag:200]]);
}
I haven't tested this, but I believe how you are handling the touch events in View A (or it's subviews) will determine how touch events are passed on. Specifically, if you're trying to use the methods: touchesBegan, touchesMoves, touchesEnded, etc instead of a UIGestureRecognizer you won't receive the touches in the way you want. Apple design the UIGestureRecognizer to handle problems like the one you're facing. Specifically, the UIScrollView uses UIPanGestureRecognizer to handle the scrolling. If you add a UIPanGestureRecognizer to each of the subviews of View A any "panning" that occurs on one of those subviews should be sent to that subview instead of the UIScrollView. However, if you're simply using the "raw" touches methods, the UIPanGestureRecognizer in UIScrollView will never be cancelled.
In general, it's almost always best to use a UIGestureRecognizer instead of processing the touches directly in the view. If you need touches processed in a way that no standard UIGestureRecognizer can provide, subclass UIGestureRecognizer and process the touches there. That way you get all the the functionality of a UIGestureRecognizer along with your own custom touch processing. I really think Apple intended for UIGestureRecognizer to replace most (if not all) of the custom touch processing code that developers use on UIView. It allows for code-reuse and it's a lot easier to deal with when mitigating what code processes what touch event.
Jacky, I needed a similar thing: Within a building plan (your A, in my case a subclass of UIScrollView), let the user place and resize objects (call them Bs). Here's a sketch of what it took me to get at this behavior:
In the superview's (A) initWithFrame: method, set these two:
self.canCancelContentTouches = YES;
self.delaysContentTouches = NO;
This will ensure taps on B are immediately routed to the Bs.
In the embedded B, stop the superview A from cancelling taps, so it does not interfere with a gesture started on the B.
In the touchesBegan: method, search the view hierarchy upwards (using superview property of the views) until you find a UIScrollView, and set its canCancelContentTouches to NO. Remember the superview you changed, and restore this property in the touchesEnded and touchesCancelled methods of B.
I'd be interested whether this works for you as well. Good Luck!
nobi
I think you had better use "touchesBegan,touchesMoved,touchesEnded" to pass the event.
you can do like this:
you should make a mainView . It has 2 property. One is yourScrollView A , and One is yourCustomView.
`[yourScrollView addSubviews:yourCustomView];
[mainView addSubviews:yourScrollView];`
and then write your touches method in the mainView.m like this (ignor the scrollView statment)
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *mytouch=[[touches allObjects] objectAtIndex:0];
if ([[touches allObjects] isKindOfClass:[yourCustomView class]])
{
//do whatever you want
}
}
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *mytouch=[[touches allObjects] objectAtIndex:0];
if ([[touches allObjects] isKindOfClass:[yourCustomView class]])
{
//do whatever you want
}
}
The last step: pass the event to the subview of the scrollView(your A).
#import "yourScrollView.h"
#implementation yourScrollView
- (id)initWithFrame:(CGRect)frame {
self = [super initWithFrame:frame];
if (self) {
// Initialization code.
}
return self;
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
[super touchesBegan:touches withEvent:event];
if(!self.dragging)
[[self nextResponder] touchesBegan:touches withEvent:event];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
[super touchesMoved:touches withEvent:event];
if(!self.dragging)
[[self nextResponder] touchesMoved:touches withEvent:event];
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{
[super touchesEnded:touches withEvent:event];
if(!self.dragging)
[[self nextResponder] touchesEnded:touches withEvent:event];
}
- (void)dealloc {
[super dealloc];
}
#end
wish to help you
A simple problem but I can't find a solution for it:
I have 2 UIViews, one above the other in the same parent view. Both have GestureRecognizers on them but only the top most is receiving the events. How can I make the top most view pass all the gestures he gets to the other UIViews beneath it?
This is how i pass touches...
Subclass the uiview
and add
-(id)hitTest:(CGPoint)point withEvent:(UIEvent *)event {
UIView *hitView = [super hitTest:point withEvent:event];
if (hitView == self){
return nil;
}
else {
return hitView;
}
}
It seems you need to use the NSNotificationCenter for the said task.
Have a look at this tutorial.
I have UIViewControllerand UITableView as child in the view,
what I want to do is when I touch any row I am displaying a view at bottom. I want to hide that view if the user touch any where else then rows or the bottomView.
The problem is when I click on UITableView it doesn't fires touchesEnded event.
Now how can I detect touch on UITableView and distinguish it with row selection event.
Thanks.
No need to subclass anything, you can add a UITapGestureRecognizer to the UITableView and absorb the gesture or not depending on your criteria.
In your viewDidLoad:
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(didTapOnTableView:)];
[self.myTableView addGestureRecognizer:tap];
Then, implement your action like this for the criteria:
-(void) didTapOnTableView:(UIGestureRecognizer*) recognizer {
CGPoint tapLocation = [recognizer locationInView:self.myTableView];
NSIndexPath *indexPath = [self.myTableView indexPathForRowAtPoint:tapLocation];
if (indexPath) { //we are in a tableview cell, let the gesture be handled by the view
recognizer.cancelsTouchesInView = NO;
} else { // anywhere else, do what is needed for your case
[self.navigationController popViewControllerAnimated:YES];
}
}
And note that if you just want to simply pick up clicks anywhere on the table, but not on any buttons in cell rows, you need only use the first code fragment above. A typical example is when you have a UITableView and there is also a UISearchBar. You want to eliminate the search bar when the user clicks, scrolls, etc the table view. Code example...
-(void)viewDidLoad {
[super viewDidLoad];
etc ...
[self _prepareTable];
}
-(void)_prepareTable {
self.tableView.separatorStyle = UITableViewCellSeparatorStyleNone;
self.tableView.allowsSelection = NO;
etc...
UITapGestureRecognizer *anyTouch =
[[UITapGestureRecognizer alloc]
initWithTarget:self action:#selector(tableTap)];
[self.tableView addGestureRecognizer:anyTouch];
}
// Always drop the keyboard when the user taps on the table:
// This will correctly NOT affect any buttons in cell rows:
-(void)tableTap {
[self.searchBar resignFirstResponder];
}
// You probably also want to drop the keyboard when the user is
// scrolling around looking at the table. If so:
-(void)scrollViewDidScroll:(UIScrollView *)scrollView {
[self.searchBar resignFirstResponder];
}
// Finally you may or may not want to drop the keyboard when
// a button in one cell row is clicked. If so:
-(void)clickedSomeCellButton... {
[self.searchBar resignFirstResponder];
...
}
Hope it helps someone.
You should forward the touch event to the view's controller.
Subclass your tableview control and then override the method:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
[super touchesBegan:touches withEvent:event]; //let the tableview handle cell selection
[self.nextResponder touchesBegan:touches withEvent:event]; // give the controller a chance for handling touch events
}
then , you can do what you want in the controller's touch methods.
I just stumbled onto what may be a solution for your problem. Use this code when you create your table view:
tableView.canCancelContentTouches = NO;
Without setting this to NO, the touch events are cancelled as soon as there is even a slight bit of vertical movement in your table view (if you put NSLog statements in your code, you'll see that touchesCancelled is called as soon as the table starts scrolling vertically).
I was facing the problem since a long time and didn't got any working solution. Finally I choose to go with a alternative. I know technically this is not the solution but this may help someone looking for the same for sure.
In my case I want to select a row that will show some option after that I touch anywhere on table or View I want to hide those options or do any task except the row selected previously for that I did following:
Set touch events for the view. This will do the task when you touch anywhere on the view except the table view.
TableView's didSelectRowAtIndexPath do following
- (void)tableView:(UITableView*)tableView didSelectRowAtIndexPath:(NSIndexPath*)indexPath {
if(indexPath.row != previousSelectedRow && previousSelectedRow != -1) {
// hide options or whatever you want to do
previousSelectedRow = -1;
}
else {
// show your options or other things
previousSelectedRow = indexPath.row;
}
}
I know that this is older post and not a good technical solution but this worked for me. I am posting this answer because this may help someone for sure.
Note: The code written here may have spell mistakes because directly typed here. :)
Try this methods:
- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView
{
}
- (void)scrollViewDidEndDragging:(UIScrollView *)scrollView willDecelerate:(BOOL)decelerate
{
}
Use scrollViewDidEndDragging like alternative of touchesEnded. Hope it helps.
To receive touch events on the UITableView use:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
//<my stuff>
[super touchesBegan:touches withEvent:event];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
//<my stuff>
[super touchesMoved:touches withEvent:event];
}
- (void)touchesEnded:(NSSet*)touches withEvent:(UIEvent*)event
{
//<my stuff>
[super touchesEnded:touches withEvent:event];
}
- (void)touchesCancelled:(NSSet*)touches withEvent:(UIEvent*)event
{
//<my stuff>
[super touchesCancelled:touches withEvent:event];
}
In your controller class declare a method which removes the bottom view. Something like this:
-(IBAction)bottomViewRemove:(id)sender {
[bottomView removeFromSuperview];
}
In Interface Builder, select your view and in the identity inspector in the custom class section, change the class from UIView to UIControl. After that go to the connections inspector and connect the TouchUpInside event to the method declared above. Hope this helps.
Why does the touchesBegan method code get trigger in my UITableView?
Background: I have a UITableView within a UINavigationController. In the UITableView I have custom cells based on subclassing UITableViewCell. I current don't have a selectRowAtIndexPath method in my UITableView.
Some aspects of the answer that would be good to cover off would include:
why it doesn't work obviously
in terms of getting it to work, how does get one ensure that the correct touch (single-tap) detection will not prevent the other scenarios to work like: selecting a table row, scrolling the tableview contents up and down etc.
should the simulator be able to pick up touches etc, or are there cases here where you need the physical device
Code:
#interface AppointmentListController : UITableViewController <UIActionSheetDelegate>
.
.
.
#implementation AppointmentListController
.
.
.
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesBegan:touches withEvent:event];
timeStampStart = event.timestamp;
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{
NSTimeInterval timeStampEnd = event.timestamp;
NSTimeInterval touchDuration = timeStampEnd - timeStampStart;
if(touchDuration > 0.2)
[super touchesEnded:touches withEvent:event];
else
DLog(#" - TOUCH EVENT OCCURS");
[super touchesEnded:touches withEvent:event];
}
Wanted to put up this as a possible answer, the answer being there is no relative straight way to achieve what I've asked for this. That is a way for a tap or double-tap to be detected in a UITableView page, which is already picking up row touches and scroll up/down etc.
Haven't verified whether this is the case or not, but people could up-vote this answer if they believe this to be true.
I've seen some threads about how to dismiss the Keyboard when a UITextField loses focus, but it did not work for me and I don't know how. The "touchesBegan:withEvent:" in the following code, never gets called. Why?
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [[event allTouches] anyObject];
if ([self.textFieldOnFocus isFirstResponder] && [touch view] != self.textFieldOnFocus) {
[textFieldOnFocus resignFirstResponder];
}
[super touchesBegan:touches withEvent:event];
}
P.S.: This code has been inserted in the view controller which has a UITableView. The UITextField is in a cell from this table.
So, my opinion is: this method is not being called, cause the touch occurs on the UITableView from my ViewController. So, I think, that to I should have to subclass the UITableView, to use this method as I have seen on other Threads, but it may have a easier way.
Could you please help me? Thanks a lot!
Make sure you set the delegate of the UITextField to First Responder in IB. And I just put a custom (invisible) UIButton over the screen and set up an IBAction to hide the keyboard. Ex:
- (IBAction)hideKeyboard {
[someTextField resignFirstResponder];
}
With that hooked up to a UIButton.
Here is my solution, somewhat inspired by several posts in SO: Simply handle the tap gesture in the context of the View, the user is 'obviously' trying to leave the focus of the UITextField.
-(void)handleViewTapGesture:(UITapGestureRecognizer *)gesture
{
[self endEditing:YES];
}
This is implemented in the ViewController. The handler is added as a gesture recognizer to the appropriate View in the View property's setter:
-(void) setLoginView:(LoginView *)loginView
{
_loginView = loginView;
UITapGestureRecognizer *tapRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self.loginView action:#selector(handleTapGesture:)];
[tapRecognizer setDelegate:self]; // self implements the UIGestureRecognizerDelegate protocol
[self.loginView addGestureRecognizer:tapRecognizer];
}
The handler could be defined in the View as well. If you are unfamiliar with handling gestures, see Apple's docs are tons of samples elsewhere.
I should mention that you will need some additional code to make sure other controls get taps, you need a delegate that implements the UIGestureRecognizerDelegate protocol and this method:
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch
{
if ([touch.view isKindOfClass:[UIButton class]]) // Customize appropriately.
return NO; // Don't let the custom gestureRecognizer handle the touch
return YES;
}
-(void)touchesEnded: (NSSet *)touches withEvent: (UIEvent *)event
{
for (UIView* view in self.view.subviews)
{
if ([view isKindOfClass:[UITextField class]])
[view resignFirstResponder];
}
}