How can I detect double tap in UIScrollview?
I tried:
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
UITouch *touch = [touches anyObject];
if (touch.tapCount == 2) {
// some operations here
}
}
But this is not detecting double tap in UIScrollView, is there any other way to detect double tap?
Regards
If you're targeting 3.2+ you could try using a UITapGestureRecognizer
UITapGestureRecognizer* tap = [[UITapGestureRecognizer alloc] initWithTarget:yourViewController action:#selector(tapGesture:)];
tap.numberOfTapsRequired = 2;
tap.numberOfTouchesRequired = 1;
[scrollView addGestureRecognizer:tap];
[tap release];
Then you handle the tap in your viewcontroller:
- (void)tapGesture:(UIGestureRecognizer*)gesture {
// Do something
}
Use the below code for double tap.
-(void) viewDidLoad{
// other necessary operations
UITapGestureRecognizer* dTap = [[UITapGestureRecognizer alloc] initWithTarget : self action : #selector (doubleTap:)];
[doubleTap setDelaysTouchesBegan : YES];
dTap.numberOfTapsRequired = 2;
dTap.numberOfTouchesRequired = 1;
[self.view addGestureRecognizer : dTap];
[dTap release];
}
- (void) doubleTap : (UIGestureRecognizer*) sender
{
NSLog (#"Double tap Do operations here...");
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
NSUInteger numTaps = [[touches anyObject] tapCount];
if (numTaps== 2) {
//some operations here
}
}
Use this Code
Related
Programmaticaly how can we close or hide drop down list when clicked outside in iphone?
-(void)RecommendDropDownSelect
{
dropDown=[[DropDownView alloc]initWithArrayData:arr_RecommendName cellHeight:30 heightTableView:100 paddingTop:-100 paddingLeft:10 paddingRight:20 refView:txt_Recommend animation:BLENDIN openAnimationDuration:0.5 closeAnimationDuration:0.5];
dropDown.delegate=self;
[scr_View addSubview:dropDown.view];
[dropDown openAnimation];
btn_RecommendDropDown.enabled=NO;
}
-(void)dropDownCellSelected:(NSInteger)returnIndex
{
btn_RecommendDropDown.enabled=YES;
txt_Recommend.text=[arr_RecommendName objectAtIndex:returnIndex];
}
Besides subclassing UIView and override touchesBegan, using UITapGestureRecognizer seems to be easier if you are using UIViewController
First, setup a tap gesture for your view:
UITapGestureRecognizer *gestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(hideDropDown)];
[gestureRecognizer setCancelsTouchesInView:NO];
[self.view addGestureRecognizer:gestureRecognizer];
then implement the method for hiding the dropdown:
- (void)hideDropDown
{
if ((dropDown != nil) && (dropDown.view != nil))
{
[drdropDown.view removeFromSuperview];
}
}
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [touches anyObject];
if (touch.view==self.view) {
[dropDown removeFromSuperView];
}
}
or
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [touches anyObject];
if (touch.view==self.view) {
dropDown.alpha=0;
}
}
Try this:
-(void)touchesBegan:(NSSet*)touches withEvent:(UIEvent*)event
{
if(dropDown)
{
[drdropDown.view removeFromSuperView];
}
}
I am trying to implement game control that will be changes direction of unit
movement. So if i do right swipe it turns to the right, if i do down swipe it turns to the down direction etc.
It's cocos2d game, and i'am using CCNode+SFGestureRecognizers with UISwipeGestureRecognizer.
At now I have next implementation for it
UISwipeGestureRecognizer *rightSwipeGestureRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleRightSwipe:)];
[self addGestureRecognizer:rightSwipeGestureRecognizer];
rightSwipeGestureRecognizer.direction = UISwipeGestureRecognizerDirectionRight;
rightSwipeGestureRecognizer.delegate = self;
[rightSwipeGestureRecognizer release];
UISwipeGestureRecognizer *upSwipeGestureRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleUpSwipe:)];
[self addGestureRecognizer:upSwipeGestureRecognizer];
upSwipeGestureRecognizer.direction = UISwipeGestureRecognizerDirectionUp;
upSwipeGestureRecognizer.delegate = self;
[upSwipeGestureRecognizer release];
UISwipeGestureRecognizer *leftSwipeGestureRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleLeftSwipe:)];
[self addGestureRecognizer:leftSwipeGestureRecognizer];
leftSwipeGestureRecognizer.direction = UISwipeGestureRecognizerDirectionLeft;
leftSwipeGestureRecognizer.delegate = self;
[leftSwipeGestureRecognizer release];
UISwipeGestureRecognizer *downSwipeGestureRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(handleDownSwipe:)];
[self addGestureRecognizer:downSwipeGestureRecognizer];
downSwipeGestureRecognizer.direction = UISwipeGestureRecognizerDirectionDown;
downSwipeGestureRecognizer.delegate = self;
[downSwipeGestureRecognizer release];
but the problem is that for to recognize the following gesture you need to lift your finger from the screen. if you do not lift a finger after the first swipe, it will recognize only the first swipe.
at now:
How it should be:
What the best way to do that? Thanks!
cancelsTouchesInView should help, it prevents the cancellation of touch events when a gesture recognizer has recognized a gesture. This will allow other gesture recognizers to continue checking for their gesture.
rightSwipeGestureRecognizer.cancelsTouchesInView = NO;
upSwipeGestureRecognizer.cancelsTouchesInView = NO;
leftSwipeGestureRecognizer.cancelsTouchesInView = NO;
downSwipeGestureRecognizer.cancelsTouchesInView = NO;
Ok, there is my solution. I dont think that is really good solution, but in my case it works, because i need getting direction at every time interval.
So, in my CCLayer subclass:
#define SWIPE_LENGTH 60
#define SWIPE_TANGENT 2
...
#property(nonatomic, assign) CGPoint latestLocation;
...
-(id) init
{
if( (self=[super init]) )
{
self.isTouchEnabled = YES;
}
return self;
}
- (void)ccTouchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = [touches anyObject];
CGPoint location = [touch locationInView:[touch view]];
location = [[CCDirector sharedDirector] convertToGL:location];
self.latestLocation = location;
}
- (void)ccTouchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = [touches anyObject];
CGPoint location = [touch locationInView:[touch view]];
location = [[CCDirector sharedDirector] convertToGL:location];
CGPoint delataLocation = CGPointMake(location.x - self.latestLocation.x, location.y - self.latestLocation.y);
if ( sqrt(pow((delataLocation.x), 2) + pow((delataLocation.y), 2) ) > SWIPE_LENGTH ) {
if (delataLocation.y > 0 && delataLocation.y > SWIPE_TANGENT * ABS(delataLocation.x))
{
[self handleSwipeWithDirestion:SDirectionTypeUp];
} else if (delataLocation.y < 0 && ABS(delataLocation.y) > SWIPE_TANGENT * ABS(delataLocation.x))
{
[self handleSwipeWithDirestion:SDirectionTypeDown];
} else if (delataLocation.x > 0 && delataLocation.x > SWIPE_TANGENT * ABS(delataLocation.y))
{
[self handleSwipeWithDirestion:SDirectionTypeRight];
} else if (delataLocation.x < 0 && ABS(delataLocation.x) > SWIPE_TANGENT * ABS(delataLocation.y))
{
[self handleSwipeWithDirestion:SDirectionTypeLeft];
}
self.latestLocation = location;
}
}
I am trying to figure out how to select an object first then I am able to move it. For example I want to select cow first by touching it then I am able to move it. The reason being is when I am touching the screen it is moving both cow and cow1. When I only want to move one cow at a time. Any help will be appreciated.
-(void) touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [touches anyObject];
CGPoint touchLocation = [touch locationInView:touch.view];
cow.center = CGPointMake(touchLocation.x, touchLocation.y);
cow1.center = CGPointMake(touchLocation.x, touchLocation.y);
}
Try using UIPanGestureRecognizer, like this:
#synthesize myImage; //UIImageView
- (void)viewDidLoad
{
[super viewDidLoad];
[self startMoveImage];
}
-(void) startMoveImage{
UIPanGestureRecognizer *panGestureRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(pan:)];
[self.view addGestureRecognizer:panGestureRecognizer];
}
- (void)pan:(UIPanGestureRecognizer *)gesture
{
if ((gesture.state == UIGestureRecognizerStateChanged) ||
(gesture.state == UIGestureRecognizerStateEnded)) {
CGPoint position = [gesture locationInView:[myImage superview]];
[myImage setCenter:position];
}
}
There are many ways to implement this sort of thing. It depends on how your graphics are implemented, amongst other things, check out this Apple sample code:
http://developer.apple.com/library/ios/#samplecode/Touches/Introduction/Intro.html
The standard solution would be to add separate gesture recognizers for your two cow objects, e.g., in viewDidLoad:
UIPanGestureRecognizer *panCow1 = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(moveCow:)];
[cow1 addGestureRecognizer:panCow1];
// if non ARC, make sure to add a line that says
// [panCow1 release];
UIPanGestureRecognizer *panCow2 = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(moveCow:)];
[cow2 addGestureRecognizer:panCow2];
// if non ARC, make sure to add a line that says
// [panCow2 release];
And then you have your moveCow method look something like:
- (void)moveCow:(UIPanGestureRecognizer *)sender
{
if (sender.state == UIGestureRecognizerStateChanged)
{
CGPoint translate = [sender translationInView:self.view];
sender.view.center = CGPointMake(sender.view.center.x + translate.x, sender.view.center.y + translate.y);
}
}
I haven't tested this code, but you get the idea. This is how I generally move separate subviews around...
I Know filtering oneTap/doubleTap using a Apple API. code are follows.
UITapGestureRecognizer *doubleTapGestureRecognizer = [[UITapGestureRecognizer alloc]
initWithTarget:self action:#selector(handleDoubleTap:)];
doubleTapGestureRecognizer.numberOfTapsRequired = 2;
[self addGestureRecognizer:doubleTapGestureRecognizer];
UITapGestureRecognizer *singleTapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleSingleTap:)];
singleTapGestureRecognizer.numberOfTapsRequired = 1;
**[singleTapGestureRecognizer requireGestureRecognizerToFail: doubleTapGestureRecognizer];**
[self addGestureRecognizer:singleTapGestureRecognizer];
but oneTap/doubleTap checkDelayTime is feeling a so Long (About 0.5sec?).
Generally App Users of the reaction is very fast. Although 0.5 seconds is typically short-time. but In Mobile Device Environment is long-time, because users react is very important.
Speaking to the point, YouTubeApp have a very Perfectly algorithm about filtering at a moment oneTap/doubleTap. oneTap-doubleTap checkDelay is VeryVeryShort Perfectly Optimization.
oneTap(show/hidden controlBar)
doubleTap(full/default videoScreenSize)
How to implement like YoutubeApp? about oneTap-doubleTap filtering Not Using a requireGestureRecognizerToFail Selector. about very short delay oneTap-doubleTap distinguishing.
I think YoutubeApp is Not Use a requireGestureRecognizer Selector.
The easiest way to do this is to subclass UITapGestureRecognizer and not a general UIGestureRecognizer.
Like this:
#import <UIKit/UIGestureRecognizerSubclass.h>
#define UISHORT_TAP_MAX_DELAY 0.2
#interface UIShortTapGestureRecognizer : UITapGestureRecognizer
#end
And simply implement:
#implementation UIShortTapGestureRecognizer
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
[super touchesBegan:touches withEvent:event];
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(UISHORT_TAP_MAX_DELAY * NSEC_PER_SEC)), dispatch_get_main_queue(), ^
{
// Enough time has passed and the gesture was not recognized -> It has failed.
if (self.state != UIGestureRecognizerStateRecognized)
{
self.state = UIGestureRecognizerStateFailed;
}
});
}
#end
This is easiest to do without gesture recognizers. Then you can control the delay. The code below is a variation of Apple's original documentation that I use in one of my projects. I have blog post that talks about it as well.
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
UITouch *touch = [touches anyObject];
if (touch.tapCount == 2) {
//This will cancel the singleTap action
[NSObject cancelPreviousPerformRequestsWithTarget:self];
}
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{
UITouch *touch = [touches anyObject];
if (touch.tapCount == 1) {
//if they tapped within the coin then place the single tap action to fire after a delay of 0.3
if (CGRectContainsPoint(coin.frame,[touch locationInView:self.view])){
//this is the single tap action being set on a delay
[self performSelector:#selector(onFlip) withObject:nil afterDelay:0.3];
}else{
//I change the background image here
}
} else if (touch.tapCount == 2) {
//this is the double tap action
[theCoin changeCoin:coin];
}
}
only thing you need to do is add extra line of code to use requireGestureRecognizerToFail
[singleTapRecognizer requireGestureRecognizerToFail:doubleTapRecognizer];
then whole code become to:
UITapGestureRecognizer *doubleTapRecognizer = [[[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(beginComicTransitions:)] autorelease];
doubleTapRecognizer.numberOfTapsRequired = 2;
doubleTapRecognizer.numberOfTouchesRequired = 1;
doubleTapRecognizer.delegate = self;
UITapGestureRecognizer *singleTapRecognizer = [[[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(bringMenu:)] autorelease];
singleTapRecognizer.numberOfTapsRequired = 1;
singleTapRecognizer.numberOfTouchesRequired = 1;
singleTapRecognizer.delegate = self;
[singleTapRecognizer requireGestureRecognizerToFail:doubleTapRecognizer];
here's requireGestureRecognizerToFail means:
if not recognized double tap, then single tap be recognized
if recognized double tap, will not recognize single tap
swift version code is:
let doubleTap = UITapGestureRecognizer(target: self, action: "doubleTapped:")
doubleTap.numberOfTapsRequired = 2
doubleTap.numberOfTouchesRequired = 1
self.scrollView.addGestureRecognizer(doubleTap)
let singleTap = UITapGestureRecognizer(target: self, action: "singleTap:")
singleTap.numberOfTapsRequired = 1
singleTap.numberOfTouchesRequired = 1
self.scrollView.addGestureRecognizer(singleTap)
singleTap.requireGestureRecognizerToFail(doubleTap)
Here is a simple custom gesture recognizers for double taps where you can specify the maximum allowed time between taps. This is based on #Walters answer.
PbDoubleTapGestureRecognizer.h :
#interface PbDoubleTapGestureRecognizer : UIGestureRecognizer
#property (nonatomic) NSTimeInterval maximumDoubleTapDuration;
#end
PbDoubleTapGestureRecognizer.m :
#import "PbDoubleTapGestureRecognizer.h"
#import <UIKit/UIGestureRecognizerSubclass.h>
#interface PbDoubleTapGestureRecognizer ()
#property (nonatomic) int tapCount;
#property (nonatomic) NSTimeInterval startTimestamp;
#end
#implementation PbDoubleTapGestureRecognizer
- (id)initWithTarget:(id)target action:(SEL)action {
self = [super initWithTarget:target action:action];
if (self) {
_maximumDoubleTapDuration = 0.3f; // assign default value
}
return self;
}
-(void)dealloc {
[NSObject cancelPreviousPerformRequestsWithTarget:self];
}
- (void)reset {
[super reset];
[NSObject cancelPreviousPerformRequestsWithTarget:self];
self.tapCount = 0;
self.startTimestamp = 0.f;
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesBegan:touches withEvent:event];
if (touches.count != 1 ) {
self.state = UIGestureRecognizerStateFailed;
} else {
if (self.tapCount == 0) {
self.startTimestamp = event.timestamp;
[self performSelector:#selector(timeoutMethod) withObject:self afterDelay:self.maximumDoubleTapDuration];
}
self.tapCount++;
}
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesMoved:touches withEvent:event];
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesEnded:touches withEvent:event];
if (self.tapCount > 2) {
self.state = UIGestureRecognizerStateFailed;
} else if (self.tapCount == 2 && event.timestamp < self.startTimestamp + self.maximumDoubleTapDuration) {
[NSObject cancelPreviousPerformRequestsWithTarget:self];
NSLog(#"Recognized in %f", event.timestamp - self.startTimestamp);
self.state = UIGestureRecognizerStateRecognized;
}
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesCancelled:touches withEvent:event];
self.state = UIGestureRecognizerStateFailed;
}
- (void)timeoutMethod {
self.state = UIGestureRecognizerStateFailed;
}
#end
You can use it like this:
PbDoubleTapGestureRecognizer *doubleTapGr = [[PbDoubleTapGestureRecognizer alloc]initWithTarget:self action:#selector(_doubleTapAction)];
doubleTapGr.maximumDoubleTapDuration = 0.4;
[yourView addGestureRecognizer:doubleTapGr];
You can combine this with requireGestureRecognizerToFail: to get the behavior that was asked for.
Swift 3.1 version of eladleb's answer.
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent) {
super.touchesBegan(touches, with: event)
DispatchQueue.main.asyncAfter(deadline: .now() + 0.3) { [weak self] in
if self?.state != .recognized {
self?.state = .failed
}
}
}
Here's a simpler answer to this problem, if you already have an action attached to the button or view. First, change the IBAction so that it includes the UIEvent (don't forget to reconnect it to your button or view in the Storyboard):
-(IBAction)buttonAction:(id)sender forEvent:(UIEvent*)event
Next, in your you can capture the touches from the event, and then easily test for the tap count:
-(IBAction)buttonAction:(id)sender forEvent:(UIEvent*)event {
UITouch* firstTouch = nil;
if ((nil != ((firstTouch = event.allTouches.allObjects.firstObject)))
&& (2 == firstTouch.tapCount))
{
// do something for double-tap
} else {
// do something for single-tap
}
}
You can extend this solution with other cases for different event parameters, such as long taps.
#interface NaMeClass ()
#property (nonatomic, strong) UITapGestureRecognizer * singleTap;
#property (nonatomic, strong) NSTimer *timer;
#end
//...code...
//viewDidLoad
self.singleTap = [[UITapGestureRecognizer alloc]initWithTarget:self action:#selector(tapIcon:)];
self.singleTap.numberOfTapsRequired = 1;
self.singleTap.cancelsTouchesInView = YES;
self.singleTap.delaysTouchesBegan = YES;
[self addGestureRecognizer:self.singleTap];
//.....code
-(void)tapIcon:(UITapGestureRecognizer *)tapGesture
{
if (tapGesture.state == UIGestureRecognizerStateEnded){
if (!self.timer) {
self.timer = [NSTimer scheduledTimerWithTimeInterval:0.2
target:self selector:#selector(singleTap) userInfo:nil repeats:NO];
}else{
[self doubleTap];
}
}
}
-(void)singleTap{
[self.timer invalidate];
self.timer = nil;
NSLog(#"1111111111111");
}
-(void)doubleTap{
[self.timer invalidate];
self.timer = nil;
NSLog(#"22222222222");
}
How to set the slider to clicked position and get the slider value on the clicked location on UISlider in iPhone programming.
i know we can drag the slider to that position but i dont want to do it. Can you please tel me how to set the slider to clicked position? Is this possible to do?
Here is the part "left as a user exercise":
- (void) tapped: (UITapGestureRecognizer*) g {
UISlider* s = (UISlider*)g.view;
if (s.highlighted)
return; // tap on thumb, let slider deal with it
CGPoint pt = [g locationInView: s];
CGFloat percentage = pt.x / s.bounds.size.width;
CGFloat delta = percentage * (s.maximumValue - s.minimumValue);
CGFloat value = s.minimumValue + delta;
[s setValue:value animated:YES];
}
The way I did it is to subclass the slider and check in touchesBegan. If the user taps on the thumb button area (which we track) then ignore the tap, but any where else on the trackbar we do:
:
-(void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [[event allTouches] anyObject];
CGPoint touchLocation = [touch locationInView:self];
// if we didn't tap on the thumb button then we set the value based on tap location
if (!CGRectContainsPoint(lastKnownThumbRect, touchLocation)) {
self.value = self.minimumValue + (self.maximumValue - self.minimumValue) * (touchLocation.x / self.frame.size.width);
}
[super touchesBegan:touches withEvent:event];
}
- (CGRect)thumbRectForBounds:(CGRect)bounds trackRect:(CGRect)rect value:(float)value {
CGRect thumbRect = [super thumbRectForBounds:bounds trackRect:rect value:value];
lastKnownThumbRect = thumbRect;
return thumbRect;
}
You can simply add a UITapGestureRecognizer to the slider, then pull out the UIEvent and Touches associated with it to figure out where along the UISlider the tap took place. Then set your slider's value to this calculated value.
UPDATE:
First, setup your slider and add the gesture recognizer to it.
UISlider *slider = [[[UISlider alloc] init] autorelease];
…
<slider setup>
…
UITapGestureRecognizer *gr = [[[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(sliderTapped:)] autorelease];
[slider addGestureRecognizer:gr];
Then implement the selector
- (void)sliderTapped:(UIGestureRecognizer *)gestureRecognizer {
<left as a user excercise*>
}
*Hint: Read the docs to figure out how to get the locationInView extrapolated and figure out what the slider should be
It seems like just subclassing UISlider and returning always true to the beginTracking produce the desired effect.
iOS 10 and Swift 3
class CustomSlider: UISlider {
override func beginTracking(_ touch: UITouch, with event: UIEvent?) -> Bool {
return true
}
}
I was using the subclassed UISlider code to listen to ValueChanged events in ios6> in order to implement a snap-to-grid type of function.
This was broken when upgrading to iOS7 as it no longer fired the UIControlEventsValueChanged. For anyone having the same problem it is fixed by adding a line in the if() as below:
-(void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [[event allTouches] anyObject];
CGPoint touchLocation = [touch locationInView:self];
// if we didn't tap on the thumb button then we set the value based on tap location
if (!CGRectContainsPoint(lastKnownThumbRect, touchLocation)) {
self.value = self.minimumValue + (self.maximumValue - self.minimumValue) * (touchLocation.x / self.frame.size.width);
[self sendActionsForControlEvents:UIControlEventValueChanged];
}
[super touchesBegan:touches withEvent:event];
}
- (CGRect)thumbRectForBounds:(CGRect)bounds trackRect:(CGRect)rect value:(float)value {
CGRect thumbRect = [super thumbRectForBounds:bounds trackRect:rect value:value];
lastKnownThumbRect = thumbRect;
return thumbRect;
}
Hope it helps someone :)
I have used this code. Get from: http://imagineric.ericd.net/2012/11/15/uislider-touch-to-set-value/
UITapGestureRecognizer *gr = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(sliderTapped:)];
[slider addGestureRecognizer:gr];
- (void)sliderTapped:(UIGestureRecognizer *)g {
UISlider* s = (UISlider*)g.view;
if (s.highlighted)
return; // tap on thumb, let slider deal with it
CGPoint pt = [g locationInView: s];
CGFloat percentage = pt.x / s.bounds.size.width;
CGFloat delta = percentage * (s.maximumValue - s.minimumValue);
CGFloat value = s.minimumValue + delta;
[s setValue:value animated:YES];
}
Hope this can help you.