I am looking for a simple answer for this problem...
I have a UITextView in which the user can start typing and click on DONE and resign the keyboard.
When the wants to edit it again, I want the cursor (the blinking line) to be at the first position of the textView, not at the end of textView. (act like a placeholder)
I tried setSelectedRange with NSMakeRange(0,0) on textViewDidBeginEditing, but it does not work.
More Info:
It can be seen that.. when the user taps on the textView the cursor comes up at the position where the user taps on the textView.
I want it to always blink at starting position when textViewDidBeginEditing.
The property selectedRange can not be assigned at "any place", to make it work you have to implement the method - (void)textViewDidChangeSelection:(UITextView *)textView, in your case:
- (void)textViewDidChangeSelection:(UITextView *)textView
{
[textView setSelectedRange:NSMakeRange(0, 0)];
}
you will have to detect when the user is beginning editing or selecting text
My solution:
- (void) viewDidLoad {
UITextView *textView = [[UITextView alloc] initWithFrame: CGRectMake(0, 0, 200, 200)];
textView.text = #"This is a test";
[self.view addSubview: textView];
textView.delegate = self;
[textView release];
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget: self action: #selector(tapped:)];
[textView addGestureRecognizer: tap];
[tap release];
}
- (void) tapped: (UITapGestureRecognizer *) tap {
[textView becomeFirstResponder];
}
- (void) textViewDidBeginEditing:(UITextView *)textView {
textView.selectedRange = NSMakeRange(0, 0);
}
I guess it's UITextView internal mechanism to set the cursor when user taps on it. We need to override that by attaching a tap gesture recognizer and call becomeFirstResponder instead.
I was facing the same issue - basically there's a delay when becoming first responder that doesn't allow you to change selectedRange in any of textView*BeginEditing: methods. If you try to delay the setSelectedRange: (let's say with performSelector:withObject:afterDelay:) it shows ugly jerk.
The solution is actually pretty simple - checking order of delegate methods gives you the hint:
textViewShouldBeginEditing:
textViewDidBeginEditing:
textViewDidChangeSelection:
Setting selectedRange in the last method (3) does the trick, you just need to make sure you reposition the cursor only for the first time when the UITextView becomes first responder as the method (3) is called every time you update the content.
A BOOL variable set in shouldChangeTextInRange: one of the methods (1), (2) and check for the variable in (3) should do the trick ... just don't forget to reset the variable after the reposition to avoid constant cursor reset :).
Hope it helps!
EDIT
After few rounds of testing I decided to set the BOOL flag in shouldChangeTextInRange: instead of (2) or (3) as it proved to be more versatile. See my code:
#interface MyClass
{
/** A flag to determine whether caret should be positioned (YES - don't position caret; NO - move caret to beginning). */
BOOL _isContentGenerated;
}
- (BOOL)textView:(UITextView *)textView shouldChangeTextInRange:(NSRange)range replacementText:(NSString *)text
{
// deleting
if([text length] == 0)
{
// deleting last character
if(range.length == [[textView text] length])
{
// reached beginning
/**
code to show placeholder and reset caret to the beginning
*/
_isContentGenerated = NO;
}
}
else
{
// adding
if(range.location == 0)
{
/**
code to hide placeholder
*/
_isContentGenerated = YES;
}
}
return YES;
}
- (void)textViewDidChangeSelection:(UITextView *)textView
{
if(!_isContentGenerated)
{
[textView setSelectedRange:NSMakeRange(0, 0)];
}
}
I haven't worked enough with that to help you fully, but what happens when you try to play with different selectedRanges? Say, if you do [... setSelectedRange:[NSMakeRange(0,1)]] or [... setSelectedRange:[NSMakeRange(1,0)]]? Does it move the cursor anywhere?
So I ended up adding a UILabel over the UITextView which acts as a placeholder for the textView. Tapping on the UILabel would send the action down to the textView and becomeFirstResponder. Once you start typing, make the label hidden.
[_detailAreaView setTextContainerInset:UIEdgeInsetsMake(8, 11, 8, 11)];
I have a custom UIButton with UILabel added as subview. Button perform given selector only when I touch it about 15points lower of top bound. And when I tap above that area nothing happens.
I found out that it hasn't caused by wrong creation of button and label, because after I shift the button lower at about 15 px it works correctly.
UPDATE I forgot to say that button located under the UINavigationBar and 1/3 of upper part of the button don't get touch events.
Image was here
View with 4 buttons is located under the NavigationBar. And when touch the "Basketball" in top, BackButton get touch event, and when touch "Piano" in top, then rightBarButton (if exists) get touch. If not exists, nothing happened.
I didn't find this documented feature in App docs.
Also I found this topic related to my problem, but there is no answer too.
I noticed that if you set userInteractionEnabled to OFF, the NavigationBar doesn't "steal" the touches anymore.
So you have to subclass your UINavigationBar and in your CustomNavigationBar do this:
-(UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event {
if ([self pointInside:point withEvent:event]) {
self.userInteractionEnabled = YES;
} else {
self.userInteractionEnabled = NO;
}
return [super hitTest:point withEvent:event];
}
Info about how to subclass UINavigationBar you can find here.
I found out the answer here(Apple Developer Forum).
Keith at Apple Developer Technical Support, on 18th May 2010 (iPhone OS 3):
I recommend that you avoid having touch-sensitive UI in such close proximity to the nav bar or toolbar. These areas are typically known as "slop factors" making it easier for users to perform touch events on buttons without the difficulty of performing precision touches. This is also the case for UIButtons for example.
But if you want to capture the touch event before the navigation bar or toolbar receives it, you can subclass UIWindow and override:
-(void)sendEvent:(UIEvent *)event;
Also I found out,that when I touch the area under the UINavigationBar, the location.y defined as 64,though it was not.
So I made this:
CustomWindow.h
#interface CustomWindow: UIWindow
#end
CustomWindow.m
#implementation CustomWindow
- (void) sendEvent:(UIEvent *)event
{
BOOL flag = YES;
switch ([event type])
{
case UIEventTypeTouches:
//[self catchUIEventTypeTouches: event]; perform if you need to do something with event
for (UITouch *touch in [event allTouches]) {
if ([touch phase] == UITouchPhaseBegan) {
for (int i=0; i<[self.subviews count]; i++) {
//GET THE FINGER LOCATION ON THE SCREEN
CGPoint location = [touch locationInView:[self.subviews objectAtIndex:i]];
//REPORT THE TOUCH
NSLog(#"[%#] touchesBegan (%i,%i)", [[self.subviews objectAtIndex:i] class],(NSInteger) location.x, (NSInteger) location.y);
if (((NSInteger)location.y) == 64) {
flag = NO;
}
}
}
}
break;
default:
break;
}
if(!flag) return; //to do nothing
/*IMPORTANT*/[super sendEvent:(UIEvent *)event];/*IMPORTANT*/
}
#end
In AppDelegate class I use CustomWindow instead of UIWindow.
Now when I touch area under navigation bar, nothing happens.
My buttons still don't get touch events,because I don't know how to send this event (and change coordinates) to my view with buttons.
Subclass UINavigationBar and add this method. It will cause taps to be passed through unless they are tapping a subview (such as a button).
-(UIView*) hitTest:(CGPoint)point withEvent:(UIEvent *)event
{
UIView *v = [super hitTest:point withEvent:event];
return v == self? nil: v;
}
The solution for me was the following one:
First:
Add in your application (It doesn't matter where you enter this code) an extension for UINavigationBar like so:
The following code just dispatch a notification with the point and event when the navigationBar is being tapped.
extension UINavigationBar {
open override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
NotificationCenter.default.post(name: NSNotification.Name(rawValue: "tapNavigationBar"), object: nil, userInfo: ["point": point, "event": event as Any])
return super.hitTest(point, with: event)
}
}
Then in your specific view controller you must listen to this notification by adding this line in your viewDidLoad:
NotificationCenter.default.addObserver(self, selector: #selector(tapNavigationBar), name: NSNotification.Name(rawValue: "tapNavigationBar"), object: nil)
Then you need to create the method tapNavigationBar in your view controller as so:
func tapNavigationBar(notification: Notification) {
let pointOpt = notification.userInfo?["point"] as? CGPoint
let eventOpt = notification.userInfo?["event"] as? UIEvent?
guard let point = pointOpt, let event = eventOpt else { return }
let convertedPoint = YOUR_VIEW_BEHIND_THE_NAVBAR.convert(point, from: self.navigationController?.navigationBar)
if YOUR_VIEW_BEHIND_THE_NAVBAR.point(inside: convertedPoint, with: event) {
//Dispatch whatever you wanted at the first place.
}
}
PD: Don't forget to remove the observation in the deinit like so:
deinit {
NotificationCenter.default.removeObserver(self)
}
That's it... That's a little bit 'tricky', but it's a good workaround for not subclassing and getting a notification anytime the navigationBar is being tapped.
I just wanted to share another prospective to solving this problem. This is not a problem by design, but it was meant to help user get back or navigate. But we need to put things tightly in or below nav bar and things look sad.
First lets look at the code.
class MyNavigationBar: UINavigationBar {
private var secondTap = false
private var firstTapPoint = CGPointZero
override func pointInside(point: CGPoint, withEvent event: UIEvent?) -> Bool {
if !self.secondTap{
self.firstTapPoint = point
}
defer{
self.secondTap = !self.secondTap
}
return super.pointInside(firstTapPoint, withEvent: event)
}
}
You might be see why am i doing second touch handling. There is the recipe to the solution.
Hit test is called twice for a call. The first time the actual point on the window is reported. Everything goes well. On the second pass, this happens.
If system sees a nav bar and the hit point is around 9 pixels more on Y side, it tries to decrease that gradually to below 44 points which is where the nav bar is.
Take a look at the screen to be clear.
So theres a mechanism that will use nearby logic to the second pass of hittest. If we can know its second pass and then call the super with first hit test point. Job done.
The above code does that exactly.
There are 2 things that might be causing problems.
Did you try setUserInteractionEnabled:NO for the label.
Second thing i think might work is apart from that after adding label on top of button you can send the label to back (it might work, not sure although)
[button sendSubviewToBack:label];
Please let me know if the code works :)
Your labels are huge. They start at {0,0} (the left top corner of the button), extend over the entire width of the button and have a height of the entire view. Check your frame data and try again.
Also, you have the option of using the UIButton property titleLabel. Maybe you are setting the title later and it goes into this label rather than your own UILabel. That would explain why the text (belonging to the button) would work, while the label would be covering the rest of the button (not letting the taps go through).
titleLabel is a read-only property, but you can customize it just as your own label (except perhaps the frame) including text color, font, shadow, etc.
This solved my problem..
I added hitTest:withEvent: code to my navbar subclass..
-(UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event {
int errorMargin = 5;// space left to decrease the click event area
CGRect smallerFrame = CGRectMake(0 , 0 - errorMargin, self.frame.size.width, self.frame.size.height);
BOOL isTouchAllowed = (CGRectContainsPoint(smallerFrame, point) == 1);
if (isTouchAllowed) {
self.userInteractionEnabled = YES;
} else {
self.userInteractionEnabled = NO;
}
return [super hitTest:point withEvent:event];
}
Extending Alexander's solution:
Step 1. Subclass UIWindow
#interface ChunyuWindow : UIWindow {
NSMutableArray * _views;
#private
UIView *_touchView;
}
- (void)addViewForTouchPriority:(UIView*)view;
- (void)removeViewForTouchPriority:(UIView*)view;
#end
// .m File
// #import "ChunyuWindow.h"
#implementation ChunyuWindow
- (void) dealloc {
TT_RELEASE_SAFELY(_views);
[super dealloc];
}
- (void)motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event {
if (UIEventSubtypeMotionShake == motion
&& [TTNavigator navigator].supportsShakeToReload) {
// If you're going to use a custom navigator implementation, you need to ensure that you
// implement the reload method. If you're inheriting from TTNavigator, then you're fine.
TTDASSERT([[TTNavigator navigator] respondsToSelector:#selector(reload)]);
[(TTNavigator*)[TTNavigator navigator] reload];
}
}
- (void)addViewForTouchPriority:(UIView*)view {
if ( !_views ) {
_views = [[NSMutableArray alloc] init];
}
if (![_views containsObject: view]) {
[_views addObject:view];
}
}
- (void)removeViewForTouchPriority:(UIView*)view {
if ( !_views ) {
return;
}
if ([_views containsObject: view]) {
[_views removeObject:view];
}
}
- (void)sendEvent:(UIEvent *)event {
if ( !_views || _views.count == 0 ) {
[super sendEvent:event];
return;
}
UITouch *touch = [[event allTouches] anyObject];
switch (touch.phase) {
case UITouchPhaseBegan: {
for ( UIView *view in _views ) {
if ( CGRectContainsPoint(view.frame, [touch locationInView:[view superview]]) ) {
_touchView = view;
[_touchView touchesBegan:[event allTouches] withEvent:event];
return;
}
}
break;
}
case UITouchPhaseMoved: {
if ( _touchView ) {
[_touchView touchesMoved:[event allTouches] withEvent:event];
return;
}
break;
}
case UITouchPhaseCancelled: {
if ( _touchView ) {
[_touchView touchesCancelled:[event allTouches] withEvent:event];
_touchView = nil;
return;
}
break;
}
case UITouchPhaseEnded: {
if ( _touchView ) {
[_touchView touchesEnded:[event allTouches] withEvent:event];
_touchView = nil;
return;
}
break;
}
default: {
break;
}
}
[super sendEvent:event];
}
#end
Step 2: Assign ChunyuWindow instance to AppDelegate Instance
Step 3: Implement touchesEnded:widthEvent: for view with buttons, for example:
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesEnded: touches withEvent: event];
UITouch *touch = [touches anyObject];
CGPoint point = [touch locationInView: _buttonsView]; // a subview contains buttons
for (UIButton* button in _buttons) {
if (CGRectContainsPoint(button.frame, point)) {
[self onTabButtonClicked: button];
break;
}
}
}
Step 4: call ChunyuWindow's addViewForTouchPriority when the view we care about appears, and call removeViewForTouchPriority when the view disappears or dealloc, in viewDidAppear/viewDidDisappear/dealloc of ViewControllers, so _touchView in ChunyuWindow is NULL, and it is the same as UIWindow, having no side effects.
An alternative solution that worked for me, based on the answer provided by Alexandar:
self.navigationController?.barHideOnTapGestureRecognizer.enabled = false
Instead of overriding the UIWindow, you can just disable the gesture recogniser responsible for the "slop area" on the UINavigationBar.
Give a extension version according to Bart Whiteley. No need to subclass.
#implementation UINavigationBar(Xxxxxx)
- (UIView*)hitTest:(CGPoint)point withEvent:(UIEvent *)event
{
UIView *v = [super hitTest:point withEvent:event];
return v == self ? nil: v;
}
#end
The following worked for me:
self.navigationController?.isNavigationBarHidden = true
i am trying to implement my own gesture recognizer in addition to the one already used by the MKMapView. Right now i can tap on the map and set a pin. This behavior is realized by my UITapGestureRecognizer. When i tap on a pin that already exists, my gesture recognizer does nothing, but instead the callout bubble of this pin is shown. The UIGestureRecognizerDelegate looks like this:
-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch
{
if (gestureRecognizer == self.tapRecognizer)
{
bool hitAnnotation = false;
int count = [self.mapView.annotations count];
int counter = 0;
while (counter < count && hitAnnotation == false )
{
if (touch.view == [self.mapView viewForAnnotation:[self.mapView.annotations objectAtIndex:counter]])
{
hitAnnotation = true;
}
counter++;
}
if (hitAnnotation)
{
return NO;
}
}
return YES;
}
This works fine. My only problem are the callout bubbles of the pins and the double tap. Normally the double tap is used for zooming in. This still works but in addition to this, i also get a new pin. Is there any way to avoid this?
The other problem occurs with the callout bubble of a pin. I can open the bubble by tapping on the pin without setting a new pin at this place (see code above) but when i want to close the bubble by tapping on it, another pin is set. My problem is, that i cannot check with touch.view , if the user tapped on a callout bubble, because it is not a regular UIView as far as i know. Any ideas or workarounds for this problem?
Thanks
I had the same problem as your first problem: distinguishing double taps from single taps in an MKMapView. What I did was the following:
[doubleTapper release];
doubleTapper = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(mapDoubleTapped:)];
doubleTapper.numberOfTapsRequired = 2;
doubleTapper.delaysTouchesBegan = NO;
doubleTapper.delaysTouchesEnded = NO;
doubleTapper.cancelsTouchesInView = NO;
doubleTapper.delegate = self;
[mapTapper release];
mapTapper = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(mapTapped:)];
mapTapper.numberOfTapsRequired = 1;
mapTapper.delaysTouchesBegan = NO;
mapTapper.delaysTouchesEnded = NO;
mapTapper.cancelsTouchesInView = NO;
[mapTapper requireGestureRecognizerToFail:doubleTapper];
and then implemented the following delegate method:
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
{
return YES;
}
Using requireGestureRecognizerToFail: allows the app to distinguish single taps from double taps and implementing gestureRecognizer:shouldRecognizeSimultaneouslyWithGestureRecognizer: ensures that double taps are still forwarded to the MKMapView so that it continues zooming normally. Note that doubleTapper doesn't actually do anything (in my case, except log debug messages). It's simply a dummy UIGestureRecognizer that's used to help separate single taps from double taps.
HI,
I have a view that has three UIScrollViews on the screen. I want to randomly scroll the UIScrollViews to different positions whenever a user shakes the iPhone, but I am unable to get it done.
I have implemented the following in my ViewController class to detect and handle the shake gesture, the 3 UIScrollViews also belong to the same class. The shake gesture is detected, but the UIScrollViews do not change. What am I doing Wrong??
i have tried both motionBegan and motionEnded.
-(BOOL)canBecomeFirstResponder {
return YES;
}
-(void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
[self becomeFirstResponder];
}
- (void)viewWillDisappear:(BOOL)animated {
[self resignFirstResponder];
[super viewWillDisappear:animated];
}
- (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event
{
if (motion == UIEventSubtypeMotionShake)
{
int randomTag = arc4random() % [dirContents count];
CGRect nextImageView = [[scrollView1 viewWithTag:2] frame];
[scrollView1 scrollRectToVisible:nextImageView animated:YES];
randomTag = arc4random() % [dirContents count];
nextImageView = [[scrollView2 viewWithTag:4] frame];
[scrollView2 scrollRectToVisible:nextImageView animated:YES];
randomTag = arc4random() % [dirContents count];
nextImageView = [[scrollView3 viewWithTag:4] frame];
[scrollView3 scrollRectToVisible:nextImageView animated:YES];
NSLog(#"Shake Detected End");
}
}
Thank You
Have you tried using SetContentOffset instead of scrollRectToVisible yet?
if the images in your tableView are of equal height the offset per "Element" is always the same.
[scrollView3 setContentOffset:yourRandomOffsetInPixels animated:YES];
maybe this works.
also consider, that The Problem might be that your shake-detection Method runs on a separate Thread this would mean that you have to call your motionEnded Method on the mainthread like so:
[self performSelectorOnMainThread:#selector(motionEnded) withObject:nil waitUntilDone:NO];
Did you check your nextImageView variable to see if it was correct ?
Further more if you are trying will have the motion of a slot machine, I would recommend you to use UITableView instead of doing it by yourself with scrollView
Just one quick question. In your example code, you generate a random tag:
randomTag = arc4random() % [dirContents count];
but then you use a specific tag value (4 in this case)? I assume it still doesn't work when you use the randomTag value? and that you were just doing some testing?
nextImageView = [[scrollView2 viewWithTag:4] frame];
I am using - (void) touchesMoved to do stuff when ever I enter a specific frame, in this case the area of a button.
My problem is, I only want it to do stuff when I enter the frame - not when I am moving my finger inside the frame.
Does anyone know how I can call my methods only once while I am inside the frame, and still allow me to call it once again if I re-enter it in the same touchMove.
Thank you.
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = [[event touchesForView:self.view] anyObject];
CGPoint location = [touch locationInView:touch.view];
if(CGRectContainsPoint(p1.frame, location))
{
//I only want the below to me called
// once while I am inside this frame
[self pP01];
[p1 setHighlighted:YES];
}else {
[p1 setHighlighted:NO];
}
}
You can use some attribute to check if the code was already called when you were entering specific area. It looks like highlighted state of p1 object (not sure what it is) may be appropriate for that:
if(CGRectContainsPoint(p1.frame, location))
{
if (!p1.isHighlighted){ // We entered the area but have not run highlighting code yet
//I only want the below to me called
// once while I am inside this frame
[self pP01];
[p1 setHighlighted:YES];
}
}else { // We left the area - so we'll call highlighting code when we enter next time
[p1 setHighlighted:NO];
}
Simply add a BOOL that you check in touchesMoved and reset in touchesEnded
if( CGRectContainsPoint([p1 frame],[touch locationInView:self.view])) {
NSLog (#"Touch Moved over p1");
if (!p14.isHighlighted) {
[self action: p1];
p1.highlighted = YES;
}
}else {
p1.highlighted = NO;
}
try using a UIButton and use the 'touch drag enter' connection in Interface Builder.