I'm making an iPhone app in which the user can do gestures (left and right swipes) to flick through tabs. My problem is that some of the pages have views such as the pickerview, webview, textfields and buttons. The swipes don't work on these. Is there any way to have global gestures?
For reference, my gesture code example:
//Swipe between tabs
#define mindrag 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) > mindrag)
{
// 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:1];
return;
}
else {
isProcessingListMove = YES;
self.tabBarController.selectedViewController = [self.tabBarController.viewControllers objectAtIndex:3];
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
Any input is appreciated.
You can subclass UIImagePickerController and UIWebView and add these gesture capturing views to them, so long as you gesture detection can still pass touches to the underlying views of course.
Related
i am using this code in my app to recognize touch and drag on specific UIView,
now i have a problem that if i make the touch and immediate make a drag the touchesMoved called only 3-4 times and stop and then the touchesCancelled called, but if i touch the screen wait a second and then make a drag it call touchesMoved every time the finger move.
Edit
Ijust tested it on iphone 4s and with this device it work perfect,in ipod4 it still have the problem. both device are with 5.01 .
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
NSArray* touchArray = [touches allObjects];
UITouch* touch = [touchArray objectAtIndex:0];
CGPoint point = [touch locationInView:self.view];
UIView *tmp = [self.view hitTest:point withEvent:event];
if (tmp == volumeViewBackground) {
//do something
}else {
NSLog(#"err");
}
}
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
NSArray* touchArray = [touches allObjects];
UITouch* touch = [touchArray objectAtIndex:0];
CGPoint point = [touch locationInView:self.view];
UIView *tmp = [self.view hitTest:point withEvent:event];
if (tmp == volumeViewBackground) {
//do something
}else {
NSLog(#"err");
}
}
-(void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event{
NSLog(#"error");
}
Try calling super according to UIResponder Class Reference.
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
[super touchesBegan: touches withEvent: event];
NSArray* touchArray = [touches allObjects];
UITouch* touch = [touchArray objectAtIndex:0];
CGPoint point = [touch locationInView:self.view];
UIView *tmp = [self.view hitTest:point withEvent:event];
if (tmp == volumeViewBackground) {
//do something
}else {
NSLog(#"err");
}
}
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
[super touchesMoved: touches withEvent: event];
NSArray* touchArray = [touches allObjects];
UITouch* touch = [touchArray objectAtIndex:0];
CGPoint point = [touch locationInView:self.view];
UIView *tmp = [self.view hitTest:point withEvent:event];
if (tmp == volumeViewBackground) {
//do something
}else {
NSLog(#"err");
}
}
-(void)touchesCancelled:(NSSet *)touches withEvent:(UIEvent *)event{
[super touchesCancelled: touches withEvent: event];
NSLog(#"error");
}
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 an UIViewController which contains a UITableView (subclassed) and another UIView (subclassed). They are on the same hierarchy level but the UIView is added last so it is the frontmost.
I overrid touchesBegan/Moved/Ended to intercept the Gestures from the top UIView: my goal is to get the selected UITableViewCell and, if double tapped, create an ImageView to be dragged around.
I appear to get it done but now I cannot scroll the UITableView anymore, even though I forward the touch events.
Here are the methods for the UIView:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
NSLog(#"BO");
UITouch * touch = [touches anyObject];
CGPoint tPoint = [touch locationInView:self];
InventoryViewController * invViewCont = self.viewController;
UITableView * invTab = invViewCont.inventoryTableView;
[invTab deselectRowAtIndexPath:[invTab indexPathForSelectedRow]
animated:YES];
NSArray * cells = [invTab visibleCells];
BOOL found = NO;
for (UITableViewCell * cell in cells)
{
if (CGRectContainsPoint(cell.frame, tPoint))
{
[cell touchesBegan:touches withEvent:event];
found = YES;
break;
}
}
if (!found)
{
[invViewCont.inventoryTableView touchesBegan:touches withEvent:event];
}
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
NSLog(#"Mo");
UITouch * touch = [touches anyObject];
CGPoint tPoint = [touch locationInView:self];
copyObj.center = tPoint;
InventoryViewController * invViewCont = self.viewController;
UITableView * invTab = invViewCont.inventoryTableView;
[invTab deselectRowAtIndexPath:[invTab indexPathForSelectedRow]
animated:YES];
NSArray * cells = [invTab visibleCells];
BOOL found = NO;
for (UITableViewCell * cell in cells)
{
if (CGRectContainsPoint(cell.frame, tPoint))
{
[cell touchesMoved:touches withEvent:event];
found = YES;
break;
}
}
if (!found)
{
[invViewCont.inventoryTableView touchesMoved:touches withEvent:event];
}
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{
UITouch * touch = [touches anyObject];
if ([touch tapCount] == 2)
{
[self desubCopyView];
}
CGPoint tPoint = [touch locationInView:self];
copyObj.center = tPoint;
InventoryViewController * invViewCont = self.viewController;
UITableView * invTab = invViewCont.inventoryTableView;
[invTab deselectRowAtIndexPath:[invTab indexPathForSelectedRow]
animated:YES];
NSArray * cells = [invTab visibleCells];
BOOL found = NO;
for (UITableViewCell * cell in cells)
{
if (CGRectContainsPoint(cell.frame, tPoint))
{
[cell touchesEnded:touches withEvent:event];
//[cell.imageView touchesEnded:touches withEvent:event];
found = YES;
break;
}
}
if (!found)
{
[invViewCont.inventoryTableView touchesEnded:touches withEvent:event];
}
}
And here are those in the UITableViewCell
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
UITouch * touch = [touches anyObject];
if ([touch tapCount] == 2)
{
CGPoint tPoint = [touch locationInView:self];
NSLog(#"CellX %lf CY %lf", tPoint.x, tPoint.y);
UIGraphicsBeginImageContext(self.bounds.size);
[self.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
UIImageView * newView = [[UIImageView alloc] initWithImage:viewImage];
[dragArea addSubview:newView];
dragArea.copyObj = newView;
[newView release];
[UIView beginAnimations:nil context:nil];
[UIView setAnimationDuration:0.4];
dragArea.copyObj.transform = CGAffineTransformMakeScale(1.3, 1.3);
[UIView commitAnimations];
tPoint = [self convertPoint:tPoint toView:dragArea];
dragArea.copyObj.center = tPoint;
}
[super touchesBegan:touches withEvent:event];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
NSLog(#"MOV %#", self.imageView.image);
[super touchesMoved:touches withEvent:event];
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{
NSLog(#"ENDED");
[super touchesEnded:touches withEvent:event];
}
And in my UITableView I have simply:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
NSLog(#"BEGTB");
[super touchesBegan:touches withEvent:event];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
NSLog(#"MOVTB");
[super touchesMoved:touches withEvent:event];
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{
NSLog(#"ENDTB");
[super touchesEnded:touches withEvent:event];
}
I am surely missing something but I do not know what
I would highly recommend looking into UITapGestureRecognizer instead of handling the touchesX events yourself.
I found a workaround for this, override the methods for touch gestures in my custom UITableView in order to make it scroll programMatically as I drag upon it an object.
Here is the 'solution'.
I still believe there is another simpler way to do this but I did not find it, so posting this and marking it as an 'answer' might help someone else.
I have a project where a UITextView (for multilines) can be dragged around the screen. So far my solution to this has been an overlay of an invisible UIButton which when dragged its center is the same as the UITextView's center.
However I've seen apps that seem to just allow the UITextView to be dragged and edited on the fly so it seems there might not be an overlay in those but I'm not sure.
Thoughts?
By the way, c in this code is the UIButton and this is how I have moved it thus far:
- (void) draggedOut: (UIControl *) c withEvent: (UIEvent *) ev
{
if(self.interfaceOrientation == UIInterfaceOrientationPortrait)
{
c.center = [[[ev allTouches] anyObject] locationInView:self.view];
AddedText.center = c.center;
}
else if(self.interfaceOrientation == UIInterfaceOrientationPortraitUpsideDown)
{
c.center = [[[ev allTouches] anyObject] locationInView:self.view];
AddedText.center = c.center;
}
else if(self.interfaceOrientation == UIInterfaceOrientationLandscapeLeft)
{
c.center = [[[ev allTouches] anyObject] locationInView:self.view];
AddedText.center = c.center;
}
else if(self.interfaceOrientation == UIInterfaceOrientationLandscapeRight)
{
c.center = [[[ev allTouches] anyObject] locationInView:self.view];
AddedText.center = c.center;
}
}
- (void)panTextView:(UIPanGestureRecognizer *)recognizer {
NSLog(#"panning");
location1 = [recognizer translationInView:draggableTextView];
recognizer.view.center = CGPointMake(recognizer.view.center.x + location1.x,
recognizer.view.center.y + location1.y);
[recognizer setTranslation:CGPointMake(0,0) inView:draggableTextView];
location1 =[recognizer locationInView:draggableTextView];
NSLog(#"tranlation %#",NSStringFromCGPoint(location1));
[_imgpic addSubview:recognizer.view];
appDelegate.txt=draggableTextView.text;
}
call this method after creating textview.
Well have not been able to manipulate the actual uitextview.
First tried making a button overlay that could be moved and could be pressed to start editing, but it wasn't centered properly.
Then tried the above method to move the UITextView itself. But it would only work on touches or drags. (Note this was a modified form of touchesBegan & touchesMoved)
Ended up with a UIScrollView with the UITextView as a subview. Now it can move smoothly just that it can be moved from any place on the screen. Not optimal but is the best result to thus keep everything else intact.
Does the textView need to support scrolling? If so, this could get complicated.
But if not, there are two approaches. 1) subclass the textview and override touchesBegan, touchesMoved, touchesEnded. 2) write a gesture recognizer that processes the same messages and attach it to the textview.
Here's an example of a Gesture recognizer that will do the job:
#interface TouchMoveGestureRecognizer : UIGestureRecognizer
{
CGPoint _ptOffset;
}
#end
#implementation TouchMoveGestureRecognizer
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch* t = [touches anyObject];
_ptOffset = [t locationInView: self.view];
}
- (void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch* t = [touches anyObject];
CGPoint pt = [t locationInView: self.view.superview];
pt.x -= _ptOffset.x;
pt.y -= _ptOffset.y;
CGRect r = self.view.frame;
r.origin = pt;
self.view.frame = r;
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
_ptOffset = CGPointMake(-1, -1);
}
#end
and, how to use it:
- (void)viewDidLoad {
[super viewDidLoad];
_textView.scrollEnabled = NO;
TouchMoveGestureRecognizer* gr = [[[TouchMoveGestureRecognizer alloc] init] autorelease];
[_textView addGestureRecognizer: gr];
}
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.