The scroller works perfectly when the tab bar item is pressed for the first time. After I switch between tab bar items, the scroller can only move down with the width and height I originally set.
This is my code
-(void)viewDidAppear:(BOOL)animated{
[scroller2 setScrollEnabled:YES];
[scroller2 setContentSize:CGSizeMake(320, 2000)];
[super viewDidAppear:animated];
I will highly appreciate suggestions.
I had the same problem... try this:
- (void) viewWillDisappear:(BOOL)animated {
[self.scrollView setContentOffset:CGPointMake(self.scrollView.contentOffset.x, 0)
animated:NO];
}
Related
I have the following code to dismiss the keyboard if the user taps the background. It works fine if the scrollview is in the PointZero position, but if the user scrolls the view and then selects the textview, it doesn't call the "dismissKeyboard' method until the 2nd background tap.
On the first tap (for some reason) moves the scrollview offset to align with the scrollview frame to the screen bottom. The second tap will dismiss the keyboard and run the code below. I know it has to do with the scrollview. Any help would be appreciated.
Thanks
- (void)viewDidLoad {
UITapGestureRecognizer *tapGesture = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(dismissKeyboard)];
tapGesture.cancelsTouchesInView = NO;
[_scrollView addGestureRecognizer:tapGesture];
}
-(void)dismissKeyboard {
[self.view endEditing:YES];
}
- (void)keyboardWasShown:(NSNotification *)notification {
scrollViewRect = _scrollView.contentOffset.y;
NSDictionary* info = [notification userInfo];
CGSize keyboardSize = [[info objectForKey:UIKeyboardFrameBeginUserInfoKey] CGRectValue].size;
keyboardSize.height += 10;
CGFloat viewBottom = CGRectGetMaxY(self.scrollView.frame);
if ([_itemNotes isFirstResponder]) {
CGFloat notesBottom = CGRectGetMaxY(_itemNotes.frame);
viewBottom -= notesBottom;
if (viewBottom < keyboardSize.height) {
keyboardSize.height -= viewBottom;
CGPoint scrollPoint = CGPointMake(0.0, keyboardSize.height);
[self.scrollView setContentOffset:scrollPoint animated:YES];
}
else {
[self.scrollView setContentOffset:CGPointZero animated:YES];
}
}
else {
[self.scrollView setContentOffset:CGPointZero animated:YES];
}
}
- (void)keyboardWillBeHidden:(NSNotification *)notification {
CGPoint scrollPoint = CGPointMake(0.0, scrollViewRect);
[self.scrollView setContentOffset:scrollPoint animated:YES];
}
EDIT:
So I figured out a solution but it seems like there must be a better way to handle this. The problem was because I was setting the contentOffset of the scrollView so that the contentSize was beyond the screen boundaries. Thus the first tap was moving the scrollView contentOffset back within the screen boundaries and the second was performing the tap gesture. I will post my solution below hoping that someone has a better answer.
I would recommend setting
_scrollView.layer.borderColor = [UIColor redColor].CGColor;
_scrollView.layer.borderWidth = 1;
This will show you exactly where your scrollview boundaries are, which may not be where you think they are, or may be covered by something else. Also, when I open the keyboard, I generally set the scrollview frame bottom to the top of the keyboard. Otherwise, you may have content below the keyboard you can't get to. Not sure if this is exactly related to your issues.
I am assuming there must be a better solution to this but I was able to solve the issue by extending the contentSize when the keyboard is displayed and then shrinking it back down when the keyboard is hidden.
Set a float (scrollViewHeight) to hold the original content size for the reset.
//add this right before setting the content offset
scrollViewHeight = _scrollView.contentSize.height;
_scrollView.contentSize = CGSizeMake(_scrollView.frame.size.width , scrollViewHeight + keyboardSize.height);
//add this right before reseting the content offset
_scrollView.contentSize = CGSizeMake(_scrollView.frame.size.width , scrollViewHeight);
It really seems like there must be a better way that I'm not aware of. I will have to go back through the documentation to see if there is another way.
After switching to iOS8, I'm getting weird behavior when I move views during a keyboard transition. Can anyone explain what's going on?
Here's a minimal example to demonstrate the problem. I have a simple view with a UITextField and a UIButton. The function nudgeUp moves the text field and the button up by 10 points. It is triggered either by the buttonPressed callback, or the keyboardWillShow callback.
When I tap the button, the code works as expected: buttonPressed calls nudgeUp and the button and text field jump up by 10 points.
When I tap the text field, keyboardWillShow calls nudgeUp, but the behaviour is very different. The button and text field immediately jump down by 10 points, and then slide back up to their original position as the keyboard shows itself.
Why is this happening? How can I regain control of animations during keyboard presentation in iOS8?
#import "ViewController.h"
#implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(keyboardWillShow:)
name:UIKeyboardWillShowNotification
object:nil];
}
- (void)keyboardWillShow:(NSNotification *)notification
{
// Called when the keyboard appears.
[self nudgeUp];
}
- (IBAction)buttonPressed:(id)sender {
[self nudgeUp];
}
- (void)nudgeUp
{
CGRect newTextFieldFrame = self.textField.frame;
newTextFieldFrame.origin.y -= 10;
self.textField.frame = newTextFieldFrame;
CGRect newButtonFrame = self.button.frame;
newButtonFrame.origin.y -= 10;
self.button.frame = newButtonFrame;
}
#end
It's AutoLayout. Something changed in iOS8 and you can't just change frame or center points anymore if you have AutoLayout enabled. You have to create an outlet(s) of your constraint (vertical space) and update it accordingly instead of changing frame position. Constraints are like any other ui control and can have an outlet. Constraint change can be animated.
Example:
[UIView animateWithDuration:[notification.userInfo[UIKeyboardAnimationDurationUserInfoKey] doubleValue] delay:0 options:[[[notification userInfo] objectForKey:UIKeyboardAnimationCurveUserInfoKey] integerValue] animations:^{
self.bottomSpaceConstraint.constant = adjustmentedValue;
[self.view layoutIfNeeded];
} completion:^(BOOL finished) {
}];
You should use UIKeyboardDidShowNotification (you're using will version) and everything will work as you expect:
- (void)viewDidLoad {
[super viewDidLoad];
[[NSNotificationCenter defaultCenter] addObserver:self
selector:#selector(keyboardDidShow:)
name:UIKeyboardDidShowNotification
object:nil];
}
- (void)keyboardDidShow:(NSNotification *)notification
{
// Called when the keyboard finished showing up
[self nudgeUp];
}
The explanation is that with UIKeyboardWillShowNotification you are changing the frames too early. After your changes the system will relayout everything to accomodate the keyboard and your changes won't have any effect.
Also, I recommend you to switch to autolayout and forget about frames.
Try using the UIKeyboardWillShowNotification userInfo to give you the frame of the keyboard. Then move the onscreen elements based on that.
I have created a secondary NSViewController to create a progress indicator "popup". The reason for this is that the software has to interact with some hardware and some of the functions take the device a few seconds to respond. So being thoughtful of the end user I have a NSViewController that has a NSView (that is black and semi-transparent) and then a message/progress bar on top. This is added to the window using addSubView.
Everything works great except when the screen has a NSTextField in it. The popup shows but the NSTextField is drawn on top. What is this?
The view code I used for drawing semi-transparent:
#implementation ConnectingView
- (id)initWithFrame:(NSRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code here.
}
return self;
}
- (void)drawRect:(NSRect)dirtyRect
{
[super drawRect:dirtyRect];
// Drawing code here.
CGContextRef context = (CGContextRef) [[NSGraphicsContext currentContext] graphicsPort];
CGContextSetRGBFillColor(context, 0.227,0.251,0.337,0.8);
CGContextFillRect(context, NSRectToCGRect(dirtyRect));
}
#end
The code I use to show the progress view
-(void) showProgressWithMessage:(NSString *) message andIsIndet:(BOOL) indet
{
connectingView = [[ConnectingViewController alloc] init];
[self.view.window.contentView addSubview:connectingView.view];
connectingView.view.frame = ((NSView*)self.view.window.contentView).bounds;
[connectingView changeProgressLabel:message];
if (indet)
[connectingView makeProgressBar:NO];
}
Is there a better way to add the subview or to tell the NSTextFields I don't want them to be drawn on top?
Thanks!
So Setting [self setWantsLayer] to my custom NSViews sort of worked however there are a lot of redraw issues (white borders, and backgrounds). A NSPopover may be better in some instances however I was going for "locked down" approach where the interface is unreachable until it finishes (or times out).
What worked for me was to go to the instance of my NSView, select the window in Interface Builder, then go to layers (far right on properties view) and select my view under "Core Animation Layer".
So I have a UIToolbar which has a custom height (which I set by overriding UIToolbar's -sizeThatFits. I want to position my UIBarButtonItems higher in the tool bar. I do so by overriding -layoutSuviews as such:
-(void)layoutSubviews
{
[super layoutSubviews];
for(UIBarButtonItem* item in self.items)
{
UIView *view;
#try {
view = [item valueForKey:#"view"];
}
#catch (NSException *exception) { NSLog(#"%#", exception.reason); }
view.frame = CGRectMake(view.frame.origin.x, view.frame.origin.y, view.frame.size.width, view.frame.size.height-33);
}
}
}
This works fine for bar buttons made with -initWithBarButtonSystemItem:, however it has no effect on bar buttons that I've made with -initWithCustomView: or -initWithTitle:.
Should I be using something different in [item valueForKey:#"view"], or is there a different way?
Never figured out a sublime answer to this question. I solved my needs by adding switches, etc to custom bar button item.
I places a UIScrollView inside the main UIView of my viewcontroller.
Then I added some controls at the bottom of the view and a UIPageControl near the top.
When i scroll the view, the bottom controls scroll fine but the UIPageControl remains in place, so it ends up blocking the buttons and labels at the bottom.
How do I make the UIPageControl and its views scroll up or down with the rest?
Here is what it looks like
I got it to work by:
1) Putting all views/controls inside a containerView and declaring it as a property.
2) Adding this code:
-(void)viewDidLayoutSubviews{
[super viewDidLayoutSubviews];
self.scrollView.contentSize = self.containerView.bounds.size;
}
- (void)viewDidLoad{
[super viewDidLoad];
//added with containerview from g8productions
self.containerView = [[UIView alloc] initWithFrame:CGRectMake(36, 59, 900, 1200)];
self.scrollView.translatesAutoresizingMaskIntoConstraints = NO;
[self.scrollView addSubview:self.containerView];
[self.scrollView setContentSize:self.containerView.bounds.size];
}
Now it scrolls! :)