Scroll on textField when begin Editing and keyboard appear - iphone

I've a viewController composed by an UIImageView that fills the whole view and two textField located at the center of the view. All this is located inside a ScrollView.
I use Storyboard and I disabled the autolayout.
When I click on a textField, and thus opens the keyboard, I'd like that the scroll is displaced directly on textField. How can I do that?

Consider that your TextField outlet is named txtField then implement UITextField Delegate using
txtField.delegate = self;
Considering that your ScrollView outlet is named scrollView. Implement the Textfield Delegate method:
- (void)textFieldDidBeginEditing:(UITextField *)textField
{
NSLog(#"%#",NSStringFromCGRect(textField.frame));
[scrollView scrollRectToVisible:textField.frame animated:YES];
}
Hope this helps.
Do let me know if you need more help.

I usually use this successfully:
http://developer.apple.com/library/ios/#documentation/StringsTextFonts/Conceptual/TextAndWebiPhoneOS/KeyboardManagement/KeyboardManagement.html

Add your controller as an observer of the keyboard notifications. When you receive the notification, resize the scroll view frame and / or set the content offset (depending on the exact effect you want and content size you have).

Here are several options that I've used before:
Apple's Doco. See the section titled Moving Content That Is Located Under the Keyboard
Cocoa With Love article, Sliding UITextFields around to avoid the keyboard
If you have several text fields or other form elements in your view, you could alternatively use something like EZForm. It does automatic repositioning of views to keep input fields visible, and also handles input validation and other useful form-related stuff.

You can convert the text field coordinate system into Scroll view coordinate system. Use the below code
-(void)rearrangeView{
// previous
if (txtActiveField == txtUsername) {
CGPoint pt;
CGRect rc = [txtUsername bounds];
rc = [txtUsername convertRect:rc toView:scrollViewLogin];
pt = rc.origin;
pt.x = 0;
pt.y -= 40;
[scrollViewLogin setContentOffset:pt animated:YES];
}
else if (txtActiveField == txtPassword) {
// [self.txtEmail becomeFirstResponder];
CGPoint pt;
CGRect rc = [txtPassword bounds];
rc = [txtPassword convertRect:rc toView:scrollViewLogin];
pt = rc.origin;
pt.x = 0;
pt.y -= 40;
[scrollViewLogin setContentOffset:pt animated:YES];
}
}
#pragma mark- UITextField Delegate
-(BOOL)textFieldShouldBeginEditing:(UITextField *)textField
{
txtActiveField = textField;
//txtActiveField.placeholder = #"";
[self rearrangeView];
return YES;
}
Here txtActiveField is instance variable of type UItextField

Related

Scrolling when the keyboard activated

I have an app where you have textfields and one textview but when I get the keyboard it hides the lower textfields. How would I do it.
I have tried:
.m:
- (void)textFieldDidBeginEditing:(UITextField *)sender {
CGSize content = _scrollView.contentSize;
_scrollView.contentSize = CGSizeMake(content.width, content.height + 200);
svos = _scrollView.contentOffset;
CGPoint pt;
CGRect rc = [sender bounds];
rc = [sender convertRect:rc toView:_scrollView];
pt = rc.origin;
pt.x = 0;
pt.y -= 200;
[_scrollView setContentOffset:pt animated:YES];
}
- (IBAction)textFieldShouldReturn:(UITextField *)textField {
CGSize content = _scrollView.contentSize;
_scrollView.contentSize = CGSizeMake(content.width, content.height - 200);
[_scrollView setContentOffset:svos animated:YES];
[textField resignFirstResponder];
}
.h:
CGPoint svos;
Although the bottom text fields are still hidden it does scroll to the visible ones
You have obtained the origin of the sender textfield but only move up by 60, thus, the lower textfields are covered by the keyboard. You will need to know the height of the keyboard and calculate the distance to move up. Check this out. It has much of the answer so I will not explain again.
To scroll to the bottom textfield inside a scrollview, add these lines in textFieldDidBeginEditing:
CGSize content = _scrollview.contentSize;
_scrollview.contentSize = CGSizeMake(content.width, content.height + 200);
This will extend your contentSize programmatically so you can scroll to the last textfield and allow the keyboard to cover the empty space.
In textFieldDidEndEditing or textFieldShouldReturn, in your case, add these:
CGSize content = _scrollview.contentSize;
_scrollview.contentSize = CGSizeMake(content.width, content.height - 200);
I used an arbitrary 200 as example. You will need to figure out how much you want.
A drop-in universal solution for moving text fields out of the way of the keyboard in iOS
https://github.com/michaeltyson/TPKeyboardAvoiding
It works perfect for me.
Simply you need to copy the required classes(TPKeyboardAvoidingScrollView or TPKeyboardAvoidingTableView) in your project and in your interface builder file you have to change the UIScrollView class to TPKeyboardAvoidingScrollView or UITableView to TPKeyboardAvoidingTableView, the remaining things will be handled by these classes.
Have you seen the documentation about managing the keyboard? (apple documentation) There is an example of what i think you are working on. Hope it helps.

presentViewController needs to be dismissed with a slide while maintaing the view underneath

I got an gridview. Each cell within that grid is clickable. If a cell is clicked, another viewcontroller must be presented as a modal viewcontroller. The presentedviewcontroller must slide in fro the right to the left. After that, the modalviewcontroller can be dismissed with a slide. How do i achieve this? I got some images to show it :
Both views are separate viewcontrollers.
[Solution]
The answer from Matthew pointed me in the right direction. What i needed was a UIPanGestureRecognizer. Because UISwipeGestureRecognizer only registers one single swipe and i needed the view to follow the users finger. I did the following to accomplish it :
If i cell is tapped inside my UICollectionView, the extra view needs to pop up. So i implemented the following code first :
/* The next piece of code represents the action called when a touch event occours on
one of the UICollectionviewCells.
*/
-(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath {
NSString* release_id = releases[indexPath.row][0];
// Next boolean makes sure that only one new view can be seen. In the past, a user can click multiple cells and it allocs multiple instances of ReleaseViewController.
if(releaseViewDismissed) {
// Alloc UIViewController and initWithReleaseID does a request to a server to initialize some data.
ReleaseViewController *releaseViewController = [[ReleaseViewController alloc] initWithReleaseID: release_id];
// Create a new UIView and assign the height and width of the grid
UIView *releaseViewHolder = [[UIView alloc] initWithFrame:CGRectMake(gridSize.width, 0, gridSize.width, gridSize.height)];
// Add the view of the releaseViewController as a subview of the newly created view.
[releaseViewHolder addSubview:releaseViewController.view];
// Then add the UIView with the view of the releaseViewController to the current UIViewController's view.
[self.view addSubview:releaseViewHolder];
// Place the x coordinate of the new view to the same as width of the screen. Then after that get the x to 0 with an animation.
[UIView animateWithDuration:0.3 animations:^{
releaseViewHolder.frame = CGRectMake(0, 0, releaseViewHolder.frame.size.width, releaseViewHolder.frame.size.height);
// This is important. alloc an UIPanGestureRecognizer and set the method that handles those events to handleSwipes.
_panGestureRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(handleSwipes:)];
// Add the UIPanGestureRecognizer to the created view.
[releaseViewHolder addGestureRecognizer:_panGestureRecognizer];
releaseViewDismissed = NO;
}];
}
}
Then my handleSwipes is as follows:
-(void)handleSwipes:(UIPanGestureRecognizer *)sender {
CGPoint translatedPoint = [(UIPanGestureRecognizer*)sender translationInView:self.view];
CGPoint translation = [sender translationInView:sender.view];
CGRect newFrame = [sender view].frame;
[sender setTranslation:CGPointZero inView:sender.view];
if (sender.state == UIGestureRecognizerStateChanged)
{
newFrame.origin.x = newFrame.origin.x + translation.x;
// Makes sure it can't go beyond the left of the screen.
if(newFrame.origin.x > 0) {
[sender view].frame = newFrame;
}
}
if(sender.state == UIGestureRecognizerStateEnded){
CGRect newFrame = [sender view].frame;
CGFloat velocityX = (0.3*[(UIPanGestureRecognizer*)sender velocityInView:self.view].x);
// If the user swipes less then half of the screen, it has to bounce back.
if(newFrame.origin.x < ([sender view].bounds.size.width/2)) {
newFrame.origin.x = 0;
}
// If a user swipes fast, the velocity is added to the new x of the frame.
if(newFrame.origin.x + velocityX > ([sender view].bounds.size.width/2)) {
newFrame.origin.x = [sender view].bounds.size.width + velocityX;
releaseViewDismissed = YES;
}
// Do it all with a animation.
[UIView animateWithDuration:0.25
animations:^{
[sender view].frame = newFrame;
}
completion:^(BOOL finished){
if(releaseViewDismissed) {
// Finally remove the new view from the superView.
[[sender view] removeFromSuperview];
}
}];
}
}
If you want the presented view controller to slide in from the right to the left, it cannot be a modal view. #Juan suggested one way to achieve the right to left and swipe back, but it would result in the grid view being pushed out of the way by the new view. If you would like the new view to cover the grid view when it slides in, you will either need to accept the vertical slide of modal views or write your own code to slide the view in from the right -- the latter would not actually be all that difficult*.
As for the swipe to get back, the easiest way to do that from either a modally presented view or a view you animate in yourself is to use a UISwipeGestureRecognizer. You create the recognizer, tell it what direction of swipe to look for, and you tell it what method to call when the swipe occurs.
*The gist of this approach is to create a UIView, add it as a subview of the grid view, and give it the same frame as your grid view but an x-position equal to the width of the view, and then use the following code to make the view animate in from the right.
[UIView animateWithDuration:0.3 animations:^{
slidingView.frame = CGRectMake(0, 0, slidingView.frame.size.width, slidingView.frame.size.height);
}];
I believe what you need is the following:
Create another controller that is going to handle navigation between these two (ContentViewController for example). This controller should have a ScrollView with paging enabled.
Here is a simple tutorial if you don´t already know how to do this: click here
Once the cell is clicked you have to:
Create the new ViewController to be shown.
Enable paging and add this ViewController to the ContentViewController
Force paging to this newly created ViewController
Additionally you have to add some logic so that when the user swipes to change back to the first page, paging is disabled until a new cell is clicked to repeat the process.

Scrolling in a table

in my table I use cells with UITextField as subview. I also can edit it but only for the upper cells in the table I also see, what I edit, because the keyboard hides the lower cells.
Now what must I do, to scroll the cell I whant to edit move to the top?
I tried
selectRowAtIndexPath:indexPathOfCurrrentCell animated:NO scrollPostion:UITableViewSchrollPositionTop
and
scrollToRowAtIndexPath:idexPathOfCurrentCell atScrollPosition:UITableViewSchrollPositionTop animated:NO
but none of it works. Must I use an other command or add something additional? What must I change?
Thanks
If you can't manually scroll the tableView to somewhere where the cell is visible; the code won't either.
The solution is to set the frame of the tableView to have a height that respects the keyboard's height of 170 points.
You could try something like this:
tableView.frame = CGRectMake(tableView.frame.origin.x, tableView.frame.origin.y, tableView.frame.size.width, tableView.frame.size.height-170);
Do this in your method which gets called when the textField becomes the first responder.
Take a look at this post. I think you'll find what you need.
Get UITableView to scroll to the selected UITextField and Avoid Being Hidden by Keyboard
Use Delegate Method of UITextField
Even I encountered this scrolling problem and i use the below logic to get rid of this.
This Works fine
-(void)textFieldDidBeginEditing:(UITextField *)textField
{
if (textField==textFieldOfYourInterest )
{
CGRect frame = self.view.frame;
if ([textField isFirstResponder] && self.view.frame.origin.y >= 0)
{
frame.origin.y -= 70;
}
else if (![textField isFirstResponder] && self.view.frame.origin.y < 0)
{
frame.origin.y += 70;
}
[self.view setFrame:frame];
}
}
- (BOOL)textFieldShouldReturn:(UITextField *)textField
{
CGRect frame = self.view.frame;
if (![topTextFieldName isFirstResponder] && self.view.frame.origin.y < 0)
{
frame.origin.y += 70;
}
[self.view setFrame:frame];
NSLog(#"text field should return");
[textField resignFirstResponder];
return YES;
}
If any problem revert to me.
Thanks
Nagaraja Sathe

UITextView text not displayed when parent view is UIScrollView UNTIL I scoll

I have a UITextView inside of a UIScrollView that is configured offscreen when the code below runs in my ViewController's viewDidLoad. Unfortunately, if the "eventDetails" text is particularly long nothing is displayed inside the UITextView until I interact with it (e.g click inside and drag for example).
My question: How to have it so the text is displayed in the UITextView WITHOUT forcing the user to interact with the UITextView first?
Here is the code:
UITextView *txtDetails = [[UITextView alloc] initWithFrame:CGRectMake(-4, yOffset, page3ScrollView.frame.size.width, 0)];
[txtDetails setEditable:NO];
[txtDetails setScrollEnabled:NO];
[txtDetails setFont:[UIFont systemFontOfSize:12]];
[txtDetails resizeAndSetTextWithMaxSize:CGSizeMake(txtDetails.frame.size.width, 999999999) forText:eventDetails withAdditionalHeightOf:16.f];
[page3ScrollView addSubview:txtDetails];
CGRect frame = txtDetails.frame;
frame.size.height = [txtDetails contentSize].height;
txtDetails.frame = frame;
[page3ScrollView setContentSize:CGSizeMake(page3ScrollView.frame.size.width, txtDetails.frame.origin.y + txtDetails.frame.size.height)];
Thanks
I was able to get this working by setting the UITextView's text ONLY when needed (e.g. is about to come on screen). Below is the relevant code:
- (void)scrollViewDidEndDecelerating:(UIScrollView *)sv
{
if (sv == scrollView) [self updatePagedView];
}
- (void)updatePagedView
{
int currentPage = pageControl.currentPage;
// *** loadDetailsPage3 is where I set the text ***
if (currentPage == 2) {
[self loadDetailsPage3];
}
}
If anyone has a better solution or needs more explanation just hit me up in the comments.
I've had the same issue and it's taken me several hours to find a suitable fix for it... Here's what I came up with...
-(void)DidBecomeActive {
if (!DidUpdateBounds) {
DidUpdateBounds = true; // instance variable set to false on load
NSString *oldtext = uiTextView.text;
//The trick is (1) removing it from it's superview
// (2) resetting it's 'text' property
// (3) re-adding it to the view WHILE it's on-screen.
[uiTextView removeFromSuperview];
uiTextView.text = oldtext;
[self.view addSubview:uiTextView];
[self.view setNeedsDisplay];
}
}
I'm using CoreAnimation to switch to this view. So right before I execute that code, I call this
//The 0,-300,480,300 is bounds of the UIView my offscreen UITextview is on
[self.view.layer setBounds:CGRectMake(0, -300, 480, 300)];
// SetNeedsDisplay, then call my method above to
//FORCIBILY redrew the UITextView while it's effectively on-screen
[self.view setNeedsDisplay];
[TextLogVC DidBecomeActive];
//CoreAnimation then goes here
This solves the issue. After setting the layer.bounds it redraws the control(UITextView) and it thinks it's onscreen. Then CoreAnimation takes care of animating from my current UIView to the new UIView and all of the text in the uiTextView is displayed throughout the animation.
Looks like the views that you are setting up are not refreshed.
And when you interact with the views then they are refreshed and your changes are rendered to the display...
Try adding [txtDetails setNeedsDisplay]; [page3ScrollView setNeedsDisplay]; after your code in viewDidLoad.
If it will help then maybe we'll find some more elegant solution...

How can I make a UIScrollView scroll to a UITextView's cursor position?

I have a view which is similar to the notes app - i.e. typing on a lined piece of paper. To make the text and the paper scroll simultaneously, I have disabled the UITextView's scrolling, and instead placed both my UITextView and my UIImageView inside a UIScrollView.
The only problem with this is that, when the user types, the text disappears below the keyboard, because obviously the UIScrollView does not know to scroll to the cursor position.
Is there any simple way I can retrieve the cursor position and tell the UIScrollView to scroll there?
---EDIT---
Starting from something similar here (where someone was trying to do something similar with a UITableView), I have managed to make a growing, editable UITextView with a fixed background that almost scrolls perfectly. The only issues now are:
There is a slight judder as the text moves up if the user types particularly fast.
If the user hides the keyboard, selects text at the bottom of the screen, and then shows the keyboard again, they have to type a couple of letters before the text becomes visible again - it doesn't scroll up immediately.
When the user hides the keyboard, the animation as the scroll view's frame fills the screen doesn't feel quite right somehow.
Here is the code - I'd be really grateful if anyone can refine it further...
#import "NoteEditViewController.h"
#import "RLWideLabelTableCell.h"
#implementation NoteEditViewController
#synthesize keyboardSize;
#synthesize keyboardHideDuration;
#synthesize scrollView;
#synthesize noteTextView;
//
// Dealloc and all that stuff
//
- (void)loadView
{
[super loadView];
UIScrollView *aScrollView = [[UIScrollView alloc] initWithFrame:self.view.bounds];
self.scrollView = aScrollView; [aScrollView release];
self.scrollView.contentSize = CGSizeMake(self.view.frame.size.width, noteTextView.frame.size.height);
[self.view addSubview:scrollView];
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Get notified when keyboard is shown. Don't need notification when hidden because we are
// using textViewDidEndEditing so we can start animating before the keyboard disappears.
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(keyboardWasShown:)
name:UIKeyboardDidShowNotification object:nil];
// Add the Done button so we can test dismissal of the keyboard
UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemDone
target:self
action:#selector(doneButton:)];
self.navigationItem.rightBarButtonItem = doneButton; [doneButton release];
// Add the background image that will scroll with the text
CGRect noteImageFrame = CGRectMake(self.view.bounds.origin.x,
noteTitleImageFrame.size.height,
self.view.bounds.size.width, 500);
UIView *backgroundPattern = [[UIView alloc] initWithFrame:noteImageFrame];
backgroundPattern.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:#"Notepaper-iPhone-Line"]];
[self.scrollView addSubview:backgroundPattern];
[self.view sendSubviewToBack:backgroundPattern];
[backgroundPattern release];
// Add the textView
CGRect textViewFrame = CGRectMake(noteImageFrame.origin.x+27,
noteImageFrame.origin.y-3,
noteImageFrame.size.width-35,
noteImageFrame.size.height);
RLTextView *textView = [[RLTextView alloc] initWithFrame:textViewFrame];
self.noteTextView = textView; [textView release];
self.noteTextView.font = [UIFont fontWithName:#"Cochin" size:21];
self.noteTextView.backgroundColor = [UIColor clearColor];
self.noteTextView.delegate = self;
self.noteTextView.scrollEnabled = NO;
[self.scrollView addSubview:self.noteTextView];
}
- (void)doneButton:(id)sender
{
[self.view endEditing:TRUE];
}
// When the keyboard is shown, the UIScrollView's frame shrinks so that it fits in the
// remaining space
- (void)keyboardWasShown:(NSNotification*)aNotification
{
NSDictionary* info = [aNotification userInfo];
CGSize kbSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
float kbHideDuration = [[info objectForKey:UIKeyboardAnimationDurationUserInfoKey] floatValue];
self.keyboardHideDuration = kbHideDuration;
self.keyboardSize = kbSize;
self.scrollView.frame = CGRectMake(self.view.bounds.origin.x,
self.view.bounds.origin.y,
self.view.bounds.size.width,
self.view.bounds.size.height - kbSize.height);
}
// When the user presses 'done' the UIScrollView expands to the size of its superview
// again, as the keyboard disappears.
- (void)textViewDidEndEditing:(UITextView *)textView
{
[UIScrollView animateWithDuration:keyboardHideDuration animations:^{self.scrollView.frame = self.view.bounds;}];
}
// This method needs to get called whenever there is a change of cursor position in the text box
// That means both textViewDidChange: and textViewDidChangeSelection:
- (void)scrollToCursor
{
// if there is a selection cursor…
if(noteTextView.selectedRange.location != NSNotFound) {
NSLog(#"selectedRange: %d %d", noteTextView.selectedRange.location, noteTextView.selectedRange.length);
// work out how big the text view would be if the text only went up to the cursor
NSRange range;
range.location = noteTextView.selectedRange.location;
range.length = noteTextView.text.length - range.location;
NSString *string = [noteTextView.text stringByReplacingCharactersInRange:range withString:#""];
CGSize size = [string sizeWithFont:noteTextView.font constrainedToSize:noteTextView.bounds.size lineBreakMode:UILineBreakModeWordWrap];
// work out where that position would be relative to the textView's frame
CGRect viewRect = noteTextView.frame;
int scrollHeight = viewRect.origin.y + size.height;
CGRect finalRect = CGRectMake(1, scrollHeight, 1, 1);
// scroll to it
[self.scrollView scrollRectToVisible:finalRect animated:YES];
}
}
// Whenever the text changes, the textView's size is updated (so it grows as more text
// is added), and it also scrolls to the cursor.
- (void)textViewDidChange:(UITextView *)textView
{
noteTextView.frame = CGRectMake(noteTextView.frame.origin.x,
noteTextView.frame.origin.y,
noteTextView.frame.size.width,
noteTextView.contentSize.height);
self.scrollView.contentSize = CGSizeMake(self.scrollView.contentSize.width,
noteTextView.frame.size.height+200);
[self scrollToCursor];
}
// The textView scrolls to the cursor whenever the user changes the selection point.
- (void)textViewDidChangeSelection:(UITextView *)aTextView
{
[self scrollToCursor];
}
// PROBLEM - the textView does not scroll until the user starts typing - just selecting
// it is not enough.
- (void)textViewDidBeginEditing:(UITextView *)textView
{
[self scrollToCursor];
}
Cool that you found my post about it, glad it was helpful!
I believe you may not be seeing the bottom line because of this line:
CGRect finalRect = CGRectMake(1, scrollHeight, 1, 1);
You're creating a 1x1 point box. A single line of text might be something like 20 or 30 points tall (depending on font size). So if you're scrolling this point to visible, it may only be showing the very top pixel of the bottom line - making the bottom line effectively invisible! If you make finalRect a little taller so it covers the whole line, it might work better:
CGRect finalRect = CGRectMake(1, scrollHeight, 1, 30);
Also, you may be calling your scrollRectToVisible code multiple times at once, which can cause "judders". In my code, I only run scrollRectToVisible from textViewDidChangeSelection, and resize the UITextView (if needed) in textViewDidChange. UIScrollView (and by inheritance UITableView) has built-in support to scroll the actively selected element to be visible, which in my testing worked well when simply resizing the UITextView while typing (but not when selecting a specific point inside with a touch).
There is no easy way to find the screen coordinates for any text or cursor in a UITextView.
What you should do is registering for UIKeyboardWillShowNotification and UIKeyboardWillShowNotification. And in the callbacks you adjust the size or contentInsets of the UIScrollView to adjust for the size of the keyboard.
The size of the keyboard, and even the animation duration is provided in the notifications userInfo, so you can do it in a nice animated fashion.
You find more information and sample code here: http://developer.apple.com/library/ios/#documentation/StringsTextFonts/Conceptual/TextAndWebiPhoneOS/KeyboardManagement/KeyboardManagement.html
Not strictly an answer to your question, but here's a different approach to the notes lined background trick: http://www.cocoanetics.com/2010/03/stuff-you-learn-from-reverse-engineering-notes-app/
I've used it and it works well.