In ios 3.1 and above how I can detect the Gesture in an UIView...
In ios >= 3.2.3 I use this code...(for example):
UISwipeGestureRecognizer *oneFingerSwipeLeft =
[[[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(oneFingerSwipeLeft:)] autorelease];
[oneFingerSwipeLeft setDirection:UISwipeGestureRecognizerDirectionLeft];
[[self view] addGestureRecognizer:oneFingerSwipeLeft];
UISwipeGestureRecognizer *oneFingerSwipeRight =
[[[UISwipeGestureRecognizer alloc] initWithTarget:self action:#selector(oneFingerSwipeRight:)] autorelease];
[oneFingerSwipeRight setDirection:UISwipeGestureRecognizerDirectionRight];
[[self view] addGestureRecognizer:oneFingerSwipeRight];
Someone have an idea/example...
Thanks
You're going to have to subclass the UIView (or implement the stuff within the view controller if the layout isn't too complicated) and track the gestures you want for yourself using ye olde UIResponder methods touchesBegan:withEvent:, etc.
For example:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
if(!trackingTouch && [touches count] == 1)
{
trackingTouch = [touches anyObject];
startingPoint = [trackingTouch locationInView:relevantView];
}
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
if(trackingTouch && [touches containsObject:trackingTouch])
{
CGPoint endingPoint = [trackingTouch locationInView:relevantView];
trackingTouch = nil;
if(endingPoint.x < startingPoint.x)
NSLog(#"swipe left");
else
NSLog(#"swipe right");
}
}
- (void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event
{
[self touchesEnded:touches withEvent:event];
}
// don't really care about touchesMoved:withEvent:
That's an imperfect solution because it assumes that all finger down to finger up progressions are necessarily swipes. You'll probably want to implement some sort of maximum time duration or track velocities in touchesMoved:withEvent: or check that the touch moved at least a minimum distance. I think it's because people were making different decisions for all of those sorts of things that Apple ended up providing the UIGestureRecognizers.
Related
I am using UISwipeGestureRecognizer to get swipe gesture in iPhone. i want to get 2 location points on Began of swipe touch and on end of swipe touch. i have implemented swipe touch method as below
- (void)handleSwipeFrom:(UISwipeGestureRecognizer *)recognizer {
CGPoint touchLocation = [recognizer locationInView:recognizer.view];
touchLocation = [[CCDirector sharedDirector] convertToGL:touchLocation];
touchLocation = [self convertToNodeSpace:touchLocation];
CCLOG(#"Hello %# - %d",NSStringFromCGPoint(touchLocation),recognizer.state);
if (recognizer.state == UIGestureRecognizerStateBegan) {
CGPoint touchLocation = [recognizer locationInView:recognizer.view];
touchLocation = [[CCDirector sharedDirector] convertToGL:touchLocation];
touchLocation = [self convertToNodeSpace:touchLocation];
CCLOG(#"UIGestureRecognizerStateBegan %#",NSStringFromCGPoint(touchLocation));
} else if (recognizer.state == UIGestureRecognizerStateChanged) {
CCLOG(#"UIGestureRecognizerStateChanged");
} else if (recognizer.state == UIGestureRecognizerStateEnded) {
CGPoint touchLocationEnd = [recognizer locationInView:recognizer.view];
touchLocationEnd = [[CCDirector sharedDirector] convertToGL:touchLocationEnd];
touchLocationEnd = [self convertToNodeSpace:touchLocationEnd];
CCLOG(#"UIGestureRecognizerStateEnded %#",NSStringFromCGPoint(touchLocationEnd));
}
//}
}
My swipe touch is working. but it only shows UIGestureRecognizerStateEnded. even when i swipe on screen and my touch is not ended yet but the StateEnded is called. how can i call StateBegin and get location and then StateEnd. right now just StateEnded is working other two Begin and Changing are not working.
Update:
I find the reason:
A swipe is a discrete gesture, and thus the associated action message
is sent only once per gesture.
And this image:
So there are only three states for UISwipeGestureRecognizer:possible, recognized and ended. But I still don't know why possible is not called.
I tried your code and get the same result. I also don't know why this happen. If you can't find solution for this problem I suggest you use the for touch methods to analysis the touch yourself. This can surely handle the event but a little complicated than use gesture recognizer.
- (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;
I was wondering how to pass on a tap on an UIView to an UITextView. This is my code so far:
- (void)foundTap:(UITapGestureRecognizer *)recognizer {
label.text = #"Touch detected";
[self.view bringSubviewToFront:aTextView];
[aTextView touchesBegan:touches withEvent:event];
}
Now, this obviously does not work as touches and event are not defined. But how do I define them? I can't declare touches as 1 (won't work). I could initialise it like so:
UITouch *touches =[touches anyObject];
But then again, touches is still undeclared. And I have no idea of how to declare the event. This is usually easy if you use the - (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {} method, but I want to pass on the tap not the touches. Any help would be very much appreciated.
Edit:
I rewrote the method, but I still can't pass on the tap to the UITextView. I now need to double tap in order to edit it, i.e. the first tap for bringing the aTextView upfront and the second tap will then edit the UITextView (as it is in front and thus receives all the touches swipes etc.):
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{
[super touchesMoved:touches withEvent:event];
UITouch *touch = [touches anyObject];
CGPoint currentPosition = [touch locationInView:self.view];
CGFloat deltaX = fabsf(gestureStartPoint.x - currentPosition.x); // will always be positive
CGFloat deltaY = fabsf(gestureStartPoint.y - currentPosition.y); // will always be positive
if (deltaY == 0 && deltaX == 0) {
label.text = #"Touch"; [self performSelector:#selector(eraseText) withObject:nil afterDelay:2];
[self.view bringSubviewToFront:aTextView];
[self.view bringSubviewToFront:doneEdit];
[aTextView touchesBegan:touches withEvent:event];
}
}
See if this previous SO question iPhone: Detecting Tap in MKMapView helps you.
This is a beginner's question I'm afraid:
I have an UIText which covers the entire screen. I have another transparent view on top of this UITextView so as to be able to recognise swiping gestures (horizontally and vertically), like so:
- (void)viewDidLoad
{
[super viewDidLoad];
// UITextView
CGRect aFrame = CGRectMake(0, 0, 320, 480);
aTextView = [[UITextView alloc] initWithFrame:aFrame];
aTextView.text = #"Some sample text.";
[self.view addSubview:aTextView];
// canTouchMe
CGRect canTouchMeFrame = CGRectMake(0, 0, 320, 480);
canTouchMe = [[UIView alloc] initWithFrame:canTouchMeFrame];
[self.view addSubview:canTouchMe];
}
Let's consider the user touches (not swipes) the canTouchMe View. In this case, I would like the canTouchMe view to disappear and pass on the touch to the UITextView hiding beneath so that it enters the editing mode and enable the 'natural' scrolling options an UITextView has (i.e. only horizontally).
My touches began method looks like this:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesBegan:touches withEvent:event];
UITouch *touch =[touches anyObject];
gestureStartPoint = [touch locationInView:self.view];
}
How do I tell this method that IF it recognises only ONE touch, that it should hide the canTouchMeFrame and PASS ON the touch to the UITextView?
Sorry if this is basic, but I have no idea how to implement this. Thanks for any suggestions.
EDIT:
I introduced a touchEnded method, but I still have no luck. The touch will not be forwarded to the UITextView. I need to tap twice in order to edit it:
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{
[super touchesMoved:touches withEvent:event];
UITouch *touch = [touches anyObject];
CGPoint currentPosition = [touch locationInView:self.view];
CGFloat deltaX = fabsf(gestureStartPoint.x - currentPosition.x); // will always be positive
CGFloat deltaY = fabsf(gestureStartPoint.y - currentPosition.y); // will always be positive
if (deltaY == 0 && deltaX == 0) {
label.text = #"Touch"; [self performSelector:#selector(eraseText) withObject:nil afterDelay:2];
[aTextView touchesBegan:touches withEvent:event];
[self.view bringSubviewToFront:aTextView];
[self.view bringSubviewToFront:doneEdit];
}
}
NSSet has a -count method. If touches only has one object, then you're responding to a single touch.
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesBegan:touches withEvent:event];
if ([touches count] == 1) {
[self hideMyRectangle];
[someOtherObject touchesBegan:touches withEvent:event];
//etc, etc.
return;
}
// if you get here, there's more than one touch.
UITouch *touch =[touches anyObject];
gestureStartPoint = [touch locationInView:self.view];
}
I have a great problem since last 2 days. I'm working with a multiple Touch enabled view. My UIViewController has 8-10 imageview. I want to detect touch on each view separately, but multiple view at a time. Touch is detected on all image view, but problem is here-
Suppose I have Tap on a image view and hold down this image view and now tap another image view, second image view is detected touch successfully but it also trigger to first image view which is previously touched and hold down. But I don't want it. So please any one help me. Code level help is appreciated.
NB. My UIViewController also implemented TouchesMoved Methods for swiping purpose.
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
for(UITouch *touch in event.allTouches) {
if(CGRectContainsPoint([imView1 frame], [touch locationInView:self.view])){
NSLog(#"imView 1 touched");
}
if(CGRectContainsPoint([imView2 frame], [touch locationInView:self.view])){
NSLog(#"imView 2 touched");
}
}
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
for(UITouch *touch in event.allTouches) {
if(CGRectContainsPoint([imView1 frame], [touch locationInView:self.view])){
NSLog(#"imView 1 touch moved");
}
if(CGRectContainsPoint([imView2 frame], [touch locationInView:self.view])){
NSLog(#"imView 2 touch moved");
}
}
}
Try subclassing a UIImageView and handle the touches code in that subclass. If you need to pass the touch to the parent for some reason, you can handle the touch then send it on to the parent which would be your view controller.
EDIT:
have your custom class like this
#interface CustomImageView : UIImageView {}#end
#implementation CustomImageView
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
NSLog(#"touch began %d",self.tag);
[self.nextResponder touchesBegan:touches withEvent:event];
}
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
NSLog(#"touch moved %d",self.tag);
[self.nextResponder touchesMoved:touches withEvent:event];
}
-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{
NSLog(#"touch ended %d",self.tag);
[self.nextResponder touchesEnded:touches withEvent:event];
}
#end
and have your parrent code something like this
#implementation trashmeTouchIpadViewController
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
NSLog(#"parent Touch Began");
//do parent stuff
}
-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{
NSLog(#"parent Touch ended");
//do parent stuff
}
- (void)viewDidLoad {
[super viewDidLoad];
[self.view setMultipleTouchEnabled:YES];
UIImage *i1 = [UIImage imageNamed:#"img1.jpg"];
CustomImageView *v1 = [[CustomImageView alloc] initWithImage:i1];
v1.frame = CGRectMake(100, 100, 200, 200);
v1.userInteractionEnabled = YES;
v1.multipleTouchEnabled = YES;
v1.tag = 111;
[self.view addSubview:v1];
[v1 release];
UIImage *i2 = [UIImage imageNamed:#"img2.jpg"];
CustomImageView *v2 = [[CustomImageView alloc] initWithImage:i2];
v2.frame = CGRectMake(500, 100, 200, 200);
v2.userInteractionEnabled = YES;
v2.multipleTouchEnabled = YES;
v2.tag = 999;
[self.view addSubview:v2];
[v2 release];
}
I have viewcontrollers set up to track gestures and commit an action, in this case, change the tab. The code for the viewcontrollers is as follows:
#define HORIZ_SWIPE_DRAG_MIN 100
CGPoint mystartTouchPosition;
BOOL isProcessingListMove;
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = [touches anyObject];
CGPoint newTouchPosition = [touch locationInView:self.view];
if(mystartTouchPosition.x != newTouchPosition.x || mystartTouchPosition.y != newTouchPosition.y) {
isProcessingListMove = NO;
}
mystartTouchPosition = [touch locationInView:self.view];
[super touchesBegan:touches withEvent:event];
}
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = touches.anyObject;
CGPoint currentTouchPosition = [touch locationInView:self.view];
// If the swipe tracks correctly.
double diffx = mystartTouchPosition.x - currentTouchPosition.x + 0.1; // adding 0.1 to avoid division by zero
double diffy = mystartTouchPosition.y - currentTouchPosition.y + 0.1; // adding 0.1 to avoid division by zero
if(abs(diffx / diffy) > 2.5 && abs(diffx) > HORIZ_SWIPE_DRAG_MIN)
{
// It appears to be a swipe.
if(isProcessingListMove) {
// ignore move, we're currently processing the swipe
return;
}
if (mystartTouchPosition.x < currentTouchPosition.x) {
isProcessingListMove = YES;
self.tabBarController.selectedViewController = [self.tabBarController.viewControllers objectAtIndex:0];
return;
}
else {
isProcessingListMove = YES;
self.tabBarController.selectedViewController = [self.tabBarController.viewControllers objectAtIndex:2];
return;
}
}
else if(abs(diffy / diffx) > 1)
{
isProcessingListMove = YES;
[super touchesMoved:touches withEvent:event];
}
}
-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
isProcessingListMove = NO;
[super touchesEnded:touches withEvent:event];
}
I'd like to have the same gesture do the same thing on a uiwebview I have set up under the view of the viewcontroller. In short, the uiwebview is on the view. When I swipe, I just get the basic uiwebview functions (scrolling). If I set up a custom uiwebview class with the same code as the uiviewcontroller, I get errors. I need to know how to translate that block of code, keeping the functionality intact, to suit the uiwebview.
You should be able to subclass UIWebView and override those methods. You may have to override all of the touch methods, though,
- (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
EDIT:
Ah, I see your errors now. They are because those things don't apply to the UIWebView like they did to the parent (which you already know...)
Since UIWebView is a UIView, you should be able to replace
[touch locationInView:self.view]
with
[touch locationInView:self]
To get to the parent's tab bar controller, though, you'll have to design a different way to do it. You could pass a reference to the parent to your UIWebView subclass and expose a method on the parent for changing which tab is active, for instance:
In your subclass, add a property for the parent tab bar controller:
UITabBarController *parent;
When creating your UIWebView subclass and adding it to the tab bar controller, also set the parent:
webView.parent = self;
If you're setting this up in Interface Builder, make the parent an IBOutlet and hook it up through IB.
In your tab bar controller view, add a method that changes the selected controller. You could use named constants for the view you want to switch to, or methods that describe exactly what you are switching to, but for simplicity, you'd do something conceptually similar this:
- (void) switchToView: (int)viewNumber
{
self.tabBarController.selectedViewController = [self.tabBarController.viewControllers objectAtIndex:viewNumber];
}
then call [parent switchToView:2] in your code.
Another and arguably better way is to use NSNotifications, registering the parent as a listener.
My full code is the following:
#import "CustomWebView.h"
#implementation CustomWebView
//Swipe between tabs
#define HORIZ_SWIPE_DRAG_MIN 100
CGPoint mystartTouchPosition;
BOOL isProcessingListMove;
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = [touches anyObject];
CGPoint newTouchPosition = [touch locationInView:self.view]; "error: request for member 'view' in something not a structure or union"
if(mystartTouchPosition.x != newTouchPosition.x || mystartTouchPosition.y != newTouchPosition.y) {
isProcessingListMove = NO;
}
mystartTouchPosition = [touch locationInView:self.view]; "error: request for member 'view' in something not a structure or union"
[super touchesBegan:touches withEvent:event];
}
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = touches.anyObject;
CGPoint currentTouchPosition = [touch locationInView:self.view]; "error: request for member 'view' in something not a structure or union"
// If the swipe tracks correctly.
double diffx = mystartTouchPosition.x - currentTouchPosition.x + 0.1; // adding 0.1 to avoid division by zero
double diffy = mystartTouchPosition.y - currentTouchPosition.y + 0.1; // adding 0.1 to avoid division by zero
if(abs(diffx / diffy) > 2.5 && abs(diffx) > HORIZ_SWIPE_DRAG_MIN)
{
// It appears to be a swipe.
if(isProcessingListMove) {
// ignore move, we're currently processing the swipe
return;
}
if (mystartTouchPosition.x < currentTouchPosition.x) {
isProcessingListMove = YES;
self.tabBarController.selectedViewController = [self.tabBarController.viewControllers objectAtIndex:0]; "error: request for member 'tabBarController' in something not a structure or union"
return;
}
else {
isProcessingListMove = YES;
self.tabBarController.selectedViewController = [self.tabBarController.viewControllers objectAtIndex:2]; "error: request for member 'tabBarController' in something not a structure or union"
return;
}
}
else if(abs(diffy / diffx) > 1)
{
isProcessingListMove = YES;
[super touchesMoved:touches withEvent:event];
}
}
-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
isProcessingListMove = NO;
[super touchesEnded:touches withEvent:event];
}
// End of swipe
#end
The errors are as follows are included with the code.
I appreciate the help.