I'm creating custom gesture recognizer. The problem is that reset method is never called so I can't reset the state of recognizer. As result it works only for the first time
#implementation TouchGestureRecognizer {
UIGestureRecognizerState mState;
}
-(UIGestureRecognizerState) state {
return mState;
}
-(void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
if( [touches count] == 1 ) {
mState = UIGestureRecognizerStateBegan;
}
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
if( [touches count] == 1 ) {
mState = UIGestureRecognizerStateChanged;
}
}
- (void)reset {
mState = UIGestureRecognizerStatePossible;
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
mState = UIGestureRecognizerStateRecognized;
}
#end
The documentation states:
The runtime calls this method after the gesture-recognizer state has been set to UIGestureRecognizerStateEnded or UIGestureRecognizerStateRecognized.
It seems that is what you are doing in touchesEnded:. Put a breakpoint in this method and take it from there.
You have to write this in your .h file.
#import <UIKit/UIGestureRecognizerSubclass.h>
Related
I used the codes below to detect touch on the object
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
NSArray *allTouches = [touches allObjects];
for (UITouch *touch in allTouches)
{
NSLog(#"TOUCH DETECT");
}
}
but it is not triggered
Welcome any comment
What kind of object? touchesBegan:withEvent: is only called for UIResponder subclasses.
Also, if it's a UIView, make sure userInteractionEnabled is YES.
How do I capture touch events such as - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event without subclassing a UIView nor using UIViewControllers.
What happens is that I have a simple UIView created programmatically and I need to detect basic tap events.
If you are writing your app for iOS 4, use UIGestureRecognizer. You can then do what you want. Recognize gestures without subclassing.
Otherwise, subclassing is the way to go.
There's just no reason not to. If you subclass and add nothing it's just a UIView called by another name. All you are doing is intercepting those functions that you are interested in. Don't forget you can do [super touchesBegan:touches] inside your subclass' touchesBegan if you don't want to stop responders up the chain from getting those events too.
I don't why you don't want to use the normal method of subclassing a UIView to capture touch events, but if you really need to do something weird or sneaky, you can capture all events (including touch events) before they get sent down the view hierarchy by trapping/handling the sendEvent: method at the UIWindow level.
CustomGestureRecognizer.h
#import <UIKit/UIKit.h>
#interface CustomGestureRecognizer : UIGestureRecognizer
{
}
- (id)initWithTarget:(id)target;
#end
CustomGestureRecognizer.mm
#import "CustomGestureRecognizer.h"
#import <UIKit/UIGestureRecognizerSubclass.h>
#interface CustomGestureRecognizer()
{
}
#property (nonatomic, assign) id target;
#end
#implementation CustomGestureRecognizer
- (id)initWithTarget:(id)target
{
if (self = [super initWithTarget:target action:Nil]) {
self.target = target;
}
return self;
}
- (void)reset
{
[super reset];
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
[super touchesBegan:touches withEvent:event];
[self.target touchesBegan:touches withEvent:event];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
[super touchesMoved:touches withEvent:event];
[self.target touchesMoved:touches withEvent:event];
}
- (void) touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
[super touchesEnded:touches withEvent: event];
[self.target touchesEnded:touches withEvent:event];
}
#end
Usage:
CustomGestureRecognizer *customGestureRecognizer = [[CustomGestureRecognizer alloc] initWithTarget:self];
[glView addGestureRecognizer:customGestureRecognizer];
I am working to make my iPhone app compatible for the iPad. The user can tap or swipe the screen to activate certain functions, and it works fine on my iPhone version. There is a UIScrollView on the page which I have subclassed to make it "swipeable," i.e. it passes up all of its touch functions to its superview as such:
#implementation SwipeableScrollView
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesBegan:touches withEvent:event];
[self.superview touchesBegan:touches withEvent:event];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesMoved:touches withEvent:event];
[self.superview touchesMoved:touches withEvent:event];
}
-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesEnded:touches withEvent:event];
[self.superview touchesEnded:touches withEvent:event];
}
#end
This works fine on the iPhone version, passing both taps and swipe gestures, but on the iPad, I get the following strange behavior:
Taps are passed to the superview properly.
But, swipe gestures are not passed at all.
Any idea why this would be working on the iPhone but not the iPad?
The problem is, that UIScrollView on the iPad cancels content touches very fast, even if canCancelContentTouches is set to NO. Also, overwriting -touchesShouldCancelInContentView: does not help. Read more here: link text
While overriding touch events was necessary on the iPhone, for the iPad Apple has introduced UIGestureRecognizers that make tasks like this much more straightforward and easy to implement. You will probably need to refactor your code to use them.
you can make custom uiscrollView and implements it's delegate so you can do what you want with scrollview it works with me fine
#import <UIKit/UIKit.h>
#protocol ScrollingDelegate <NSObject>
#required
- (void)scrolltouchesBegan:(NSSet *)touches withEvent:(UIEvent *)event;
- (void)scrolltouchesMoved:(NSSet *)touches withEvent:(UIEvent *)event;
- (void)scrolltouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event;
#end
Implementation
#interface CustomScrollView : UIScrollView
{
id <ScrollingDelegate> delegate;
}
#property (nonatomic,strong) id scrollDelegate;
#end
#import "CustomScrollView.h"
#implementation CustomScrollView
#synthesize scrollDelegate;
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code
}
return self;
}
- (id)initWithCoder:(NSCoder *)aDecoder
{
self=[super initWithCoder:aDecoder];
if (self)
{
}
return self;
}
-(BOOL)touchesShouldCancelInContentView:(UIView *)view
{
return NO;
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
[self.scrollDelegate scrolltouchesBegan:touches withEvent:event];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
[self.scrollDelegate scrolltouchesMoved:touches withEvent:event];
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
[self.scrollDelegate scrolltouchesEnded:touches withEvent:event];
}
-(void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
}
#end
I have a UITextView in a custom UITableViewCell. The textview works properly (scrolls, shows text, etc.) but I need the users to be able to tap the table cell and go to another screen. Right now, if you tap the edges of the table cell (i.e. outside the UItextView) the next view is properly called. But clearly inside the uitextview the touches are being captured and not forwarded to the table cell.
I found a post that talked about subclassing UITextView to forward the touches. I tried that without luck. The implementation is below. I'm wondering if maybe a) the super of my textview isn't the uitableviewcell and thus I need to pass the touch some other way or b) If the super is the uitableviewcell if I need to pass something else? Any help would be much appreciated.
#import "ScrollableTextView.h"
#implementation ScrollableTextView
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
if (parentScrollView) {
[parentScrollView touchesBegan:touches withEvent:event];
}
[super touchesBegan:touches withEvent:event];
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event {
if (parentScrollView) {
[parentScrollView touchesCancelled:touches withEvent:event];
}
[super touchesCancelled:touches withEvent:event];
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
if (parentScrollView) {
[parentScrollView touchesEnded:touches withEvent:event];
}
[super touchesEnded:touches withEvent:event];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
if (parentScrollView) {
[parentScrollView touchesMoved:touches withEvent:event];
}
[super touchesMoved:touches withEvent:event];
}
- (BOOL)canBecomeFirstResponder {
return YES;
}
#end
Try [theTextView setUserInteractionEnabled:NO]; If the user needs to be able to edit the contents of the TextView, then you might have a design problem here.
Swift 3 : theTextView.isUserInteractionEnabled = false
Storyboard : tick the "User Interaction Enabled" checkbox.
I know that this question has been asked 5 years ago, but the behaviour is still very much needed for some app to have a clickable Cell with UIDataDetectors.
So here's the UITextView subclass I made up to fit this particular behaviour in a UITableView
-(id) initWithFrame:(CGRect)frame {
self = [super initWithFrame:frame];
if (self) {
self.delegate = self;
}
return self;
}
- (BOOL)canBecomeFirstResponder {
return NO;
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UIView *obj = self;
do {
obj = obj.superview;
} while (![obj isKindOfClass:[UITableViewCell class]]);
UITableViewCell *cell = (UITableViewCell*)obj;
do {
obj = obj.superview;
} while (![obj isKindOfClass:[UITableView class]]);
UITableView *tableView = (UITableView*)obj;
NSIndexPath *indePath = [tableView indexPathForCell:cell];
[[tableView delegate] tableView:tableView didSelectRowAtIndexPath:indePath];
}
- (BOOL)textView:(UITextView *)textView shouldInteractWithURL:(NSURL *)URL inRange:(NSRange)characterRange {
return YES;
}
You can modify this to fit your needs...
Hope it helps someone.
The problem with your solution is that if you put UITextView inside UITableViewCell, its superview won't be the actual cell. There's even a slight difference between iOS 7 and iOS 8 on the cell's view structure. What you need to do is drill down (or drill up) through the hierarchy to get UITableViewCell instance.
I am using and modifying #TheSquad's while loop to get the UITableViewCell, and assign it to a property. Then override those touch methods, use the cell's touches method whenever needed, and just use super's touch method's implementations to get the default behaviour.
// set the cell as property
#property (nonatomic, assign) UITableViewCell *superCell;
- (UITableViewCell *)superCell {
if (!_superCell) {
UIView *object = self;
do {
object = object.superview;
} while (![object isKindOfClass:[UITableViewCell class]] && (object != nil));
if (object) {
_superCell = (UITableViewCell *)object;
}
}
return _superCell;
}
#pragma mark - Touch overrides
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
if (self.superCell) {
[self.superCell touchesBegan:touches withEvent:event];
} else {
[super touchesBegan:touches withEvent:event];
}
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
if (self.superCell) {
[self.superCell touchesMoved:touches withEvent:event];
} else {
[super touchesMoved:touches withEvent:event];
}
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
if (self.superCell) {
[self.superCell touchesEnded:touches withEvent:event];
} else {
[super touchesEnded:touches withEvent:event];
}
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event {
if (self.superCell) {
[self.superCell touchesEnded:touches withEvent:event];
} else {
[super touchesCancelled:touches withEvent:event];
}
}
The answers above don't solve the problem if you have links in the UITextView and want them to work as usual when user taps a link, and pass the tap to the cell if user taps regular text. With the proposed method cell will be "selected" in both cases.
Here are some possible solutions:
https://stackoverflow.com/a/59010352/11448489 - add a tap gesture recognizer to the cell, and set it to require UITextInteractionNameLinkTap recognizer failure. The problem is that UITextInteractionNameLinkTap string is from internal Apple API and can change. Also, we still have to directly call delegate's didSelectRowAtIndexPath, so the cell won't be animated.
Implement override of touchesEnded in the text view. In it perform some selector after delay of at least 0.4s. In the text view delegate cancel this perform request if an interaction with url happened:
class TappableTextView: UITextView, UITextViewDelegate {
var tapHandler: (() -> Void)?
override var delegate: UITextViewDelegate? {
get { self }
set { }
}
override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
self.perform(#selector(onTap), with: nil, afterDelay: 0.5)
}
func textView(_ textView: UITextView, shouldInteractWith URL: URL, in characterRange: NSRange, interaction: UITextItemInteraction) -> Bool {
Self.cancelPreviousPerformRequests(withTarget: self, selector: #selector(onTap), object: nil)
return true
}
#objc func onTap() {
self.tapHandler?()
}
}
It works, but delay is noticeable and annoying. It is not possible to reduce this delay because shouldInteractWith happens after 350ms after touchesEnded.
And we still have to call didSelectRowAtIndexPath.
I came to another solution, which seems to work perfectly if you need clickable links, but no other interactions (not scrollable, selectable etc). Essentially, we need to make the text view ignore all touches which are not in the links area:
class TapPassingTextView: UITextView, UITextViewDelegate {
var clickableRects = [CGRect]()
override func layoutSubviews() {
super.layoutSubviews()
self.updateClickableRects()
}
override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
clickableRects.contains { $0.contains(point) } ? super.hitTest(point, with: event) : nil
}
private func updateClickableRects() {
self.clickableRects = []
let range = NSRange(location: 0, length: self.attributedText.string.count)
self.attributedText.enumerateAttribute(.link, in: range) { link, range, _ in
guard link != nil else { return }
self.layoutManager.enumerateLineFragments(forGlyphRange: range) { rect, _, _, _, _ in
self.clickableRects.append(rect)
}
}
}
}
That's it! Taps on links are working and taps in other areas go below the text view, cells are selected natively.
Is there a bug in the 3.0 SDK that disables real-time zooming and intercepting the zoom-in gesture for the MKMapView? I have some real simple code so I can detect tap events, but there are two problems:
zoom-in gesture is always interpreted as a zoom-out
none of the zoom gestures update the Map's view in realtime.
In hitTest, if I return the "map" view, the MKMapView functionality works great, but I don't get the opportunity to intercept the events.
Any ideas?
MyMapView.h:
#interface MyMapView : MKMapView
{
UIView *map;
}
MyMapView.m:
- (id)initWithFrame:(CGRect)frame
{
if (![super initWithFrame:frame])
return nil;
self.multipleTouchEnabled = true;
return self;
}
- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event {
NSLog(#"Hit Test");
map = [super hitTest:point withEvent:event];
return self;
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
NSLog(#"%s", __FUNCTION__);
[map touchesCancelled:touches withEvent:event];
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent*)event
{
NSLog(#"%s", __FUNCTION__);
[map touchesBegan:touches withEvent:event];
}
- (void)touchesMoved:(NSSet*)touches withEvent:(UIEvent*)event
{
NSLog(#"%s, %x", __FUNCTION__, mViewTouched);
[map touchesMoved:touches withEvent:event];
}
- (void)touchesEnded:(NSSet*)touches withEvent:(UIEvent*)event
{
NSLog(#"%s, %x", __FUNCTION__, mViewTouched);
[map touchesEnded:touches withEvent:event];
}
The best way I have found to achieve this is with a Gesture Recognizer. It's unclear if you want to recognize zoom events yourself or just detect when the user is zooming/panning.
I don't need to detect a map pan or zoom--i just care if the user has put a finger down anywhere in the MKMapView. If you need to detect zooming or panning with 100% recall and precision, it might be more complicated than this. What we really need is an open source implementation of MKMapView so we can add this to the delegate, among many other features.
Here's what I do: Implement a gesture recognizer that cannot be prevented and that cannot prevent other gesture recognizers. Add it to the map view and deal with the relevant touch events as you desire.
How to detect any tap inside an MKMapView (sans tricks)
WildcardGestureRecognizer * tapInterceptor = [[WildcardGestureRecognizer alloc] init];
tapInterceptor.touchesBeganCallback = ^(NSSet * touches, UIEvent * event) {
self.lockedOnUserLocation = NO;
};
[mapView addGestureRecognizer:tapInterceptor];
WildcardGestureRecognizer.h
//
// WildcardGestureRecognizer.h
// Copyright 2010 Floatopian LLC. All rights reserved.
//
#import <Foundation/Foundation.h>
typedef void (^TouchesEventBlock)(NSSet * touches, UIEvent * event);
#interface WildcardGestureRecognizer : UIGestureRecognizer {
TouchesEventBlock touchesBeganCallback;
}
#property(copy) TouchesEventBlock touchesBeganCallback;
#end
WildcardGestureRecognizer.m
//
// WildcardGestureRecognizer.m
// Created by Raymond Daly on 10/31/10.
// Copyright 2010 Floatopian LLC. All rights reserved.
//
#import "WildcardGestureRecognizer.h"
#implementation WildcardGestureRecognizer
#synthesize touchesBeganCallback;
-(id) init{
if (self = [super init])
{
self.cancelsTouchesInView = NO;
}
return self;
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
if (touchesBeganCallback)
touchesBeganCallback(touches, event);
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
}
- (void)reset
{
}
- (void)ignoreTouch:(UITouch *)touch forEvent:(UIEvent *)event
{
}
- (BOOL)canBePreventedByGestureRecognizer:(UIGestureRecognizer *)preventingGestureRecognizer
{
return NO;
}
- (BOOL)canPreventGestureRecognizer:(UIGestureRecognizer *)preventedGestureRecognizer
{
return NO;
}
#end
I had the same problem - I wanted to draw map scales on top of Map View. In order to do it I had to intercept the touch events, and then send them back to the Map View. Unfortunately, when the MKMapView isn't the original receiver of the events, some smooth panning and zooming animations are not working any more.
However I have found a solution to this problem - a bit hacky but works:
1. I have put my MapScales UIView on top of MKMapView, and turned off receiving events in it, so that underlying MKMapView received the events by default.
2. I have subclassed UIWindow with MyMainWindow class and in it I have overriden the method:
- (void) sendEvent:(UIEvent*)event {
[super sendEvent:event];
[self send_the_event_also_to_my_MapScales_component_with_use_of_listener_design_pattern];
}
I have made the main window of my application an instasnce of MyMainWindow.
In this way my MapScales component receives and can react to all the touch events, and at the same time it is not spoiling the underlying MKMapView :)
#import <UIKit/UIKit.h>
#import "UIViewTouch.h"
#import <MapKit/MapKit.h>
#interface MapTouchAppDelegate : NSObject <UIApplicationDelegate>
{
UIViewTouch *viewTouch;
MKMapView *mapView;
UIWindow *window;
}
#property (nonatomic, retain) IBOutlet UIWindow *window;
#property (nonatomic, retain) UIViewTouch *viewTouch;
#property (nonatomic, retain) MKMapView *mapView;
#end
#import "MapTouchAppDelegate.h"
#implementation MapTouchAppDelegate
#synthesize window;
#synthesize viewTouch;
#synthesize mapView;
- (void)applicationDidFinishLaunching:(UIApplication *)application
{
//We create a view wich will catch Events as they occured and Log them in the Console
viewTouch = [[UIViewTouch alloc] initWithFrame:CGRectMake(0, 0, 320, 480)];
//Next we create the MKMapView object, which will be added as a subview of viewTouch
mapView = [[MKMapView alloc] initWithFrame:CGRectMake(0, 0, 320, 480)];
[viewTouch addSubview:mapView];
//And we display everything!
[window addSubview:viewTouch];
// Override point for customization after application launch
[window makeKeyAndVisible];
}
- (void)dealloc {
[window release];
[super dealloc];
}
#import <UIKit/UIKit.h>
#interface UIViewTouch : UIView
{
UIView *viewTouched;
}
#property (nonatomic, retain) UIView * viewTouched;
- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event;
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event;
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event;
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event;
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event;
#end
#import "UIViewTouch.h"
#implementation UIViewTouch
#synthesize viewTouched;
//The basic idea here is to intercept the view which is sent back as the firstresponder in hitTest.
//We keep it preciously in the property viewTouched and we return our view as the firstresponder.
- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
{
NSLog(#"Hit Test");
self.multipleTouchEnabled = true;
viewTouched = [super hitTest:point withEvent:event];
return self;
}
//Then, when an event is fired, we log this one and then send it back to the viewTouched we kept, and voilà!!! :)
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
NSLog(#"Touch Began");
[viewTouched touchesBegan:touches withEvent:event];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
NSLog(#"Touch Moved");
[viewTouched touchesMoved:touches withEvent:event];
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
NSLog(#"Touch Ended");
[viewTouched touchesEnded:touches withEvent:event];
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
NSLog(#"Touch Cancelled");
}
#end
This code will detect touches as well as zooming.
Try
[super touchesEnded:touches withEvent:event];
instead of
[map touchesEnded:touches withEvent:event];
And apply this idea to all of the touch event methods. That way, the touches should travel down the responder chain, and peace will be restored.
To extend up on #chomasek's answer, in order to only process those touches for the map view, I do the following:
Give the map view a tag, like 99
When I get touch, traverse up the view hierarchy of the receiving view, looking for a view with the above tag.
Here is the code:
// this is in the view controller containing the map view
// kICTagForMapView is just a constant
_mapView.tag = kICTagForMapView;
Then in sendEvent:
// this does into the UIWindow subclass
BOOL isMapView = NO;
UIView* superView = touch.view.superview;
while(superView)
{
//Debug(#"superView = %#", superView);
if (superView.tag == kICTagForMapView)
{
isMapView = YES;
break;
}
superView = superView.superview;
}
if (isMapView == NO) return;
// do stuff here
MKMapView does not respond to the touch methods listed above...