I have a tableView. on view is UIButton. i want when scroll down button fade and when scroll stop or up button show.
code:
- (void)scrollViewWillBeginDecelerating:(UIScrollView *)scrollView{
NSLog(#"Start scroll");
//I assume the buttons are within your cells so you will have to enable them within your cells so you will probably have to handle this by sending a custom message to your cells or accessing them with properties.
CGRect frame = addCommentBtn.frame;
frame.origin.y = scrollView.contentOffset.y + self.newsTableView.frame.size.height + 4;
addCommentBtn.frame = frame;
[self.view bringSubviewToFront:addCommentBtn];}
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView{
NSLog(#"End scroll");
// do the same to enable them back
CGRect frame = addCommentBtn.frame;
frame.origin.y = scrollView.contentOffset.y + self.newsTableView.frame.size.height + 4;
addCommentBtn.frame = frame;
[self.view bringSubviewToFront:addCommentBtn];}
but don't work correctly!
Thanks
You are using wrong method. Instead of
scrollViewWillBeginDecelerating: use scrollViewDidScroll: and update button alpha and position based on contentOffset of the scroll view.
Related
So far I have customized the tableview and implemented the iPad General Setting Page. Below is the code for tableview which will change frame accordingly. But the issue is when I insert/delete rows or section in the tableview. My tableviewcell backgroundview (not cell) width get shrinks. Any idea what wrong am I doing here?
- (void)setFrame:(CGRect)frame
{
if (UI_USER_INTERFACE_IDIOM()==UIUserInterfaceIdiomPad)
{
CGFloat inset =10;
frame.origin.x += inset;
frame.size.width -= 2 * inset;//The issue is in this line
}
[super setFrame:frame];
}
I found the simple solution to achieve this. No need of customizing UITableView subclass. Just take the outlet of tableview and set the frame and change the color of backgroundview. like that below:-
CGFloat tableBorderLeft = 10;
CGFloat tableBorderRight = 10;
CGRect tableRect = self.view.frame;
tableRect.origin.x += tableBorderLeft; // make the table begin a few pixels right from its origin
tableRect.size.width -= tableBorderLeft + tableBorderRight; // reduce the width of the table
yourTableView.frame = tableRect;
self.view.backgroundColor=[UIColor colorWithRed:(239/255.0f) green:(239/255.0f) blue:(244/255.0f) alpha:1.0];
I want animation like home screen of this app.This screen has a view (with a label on it) on top and a table view under it. When i scroll the table the top view and title on it become small with animation and after a specific point it becomes like navigation bar with title in centre. And the same thing when i scroll down.
Here is what i tried so far
-(void)scrollViewDidScroll:(UIScrollView *)scrollView
{
CGPoint offset = scrollView.contentOffset;
NSLog(#"y is::: %f", offset.y);
if (offset.y > 0 && offset.y < 16 && self.topView.frame.size.height > 64) {
[UIView animateWithDuration:0.8 animations:^{
CGRect rect = self.topView.frame;
rect.size.height = rect.size.height-offset.y;
self.topView.frame = rect;
}completion:^(BOOL finish){
}];
}
else if(offset.y <= 0 && offset.y > -16 && self.topView.frame.size.height < 80)
{
[UIView animateWithDuration:0.8 animations:^{
CGRect rect = self.topView.frame;
rect.size.height = 80;
self.topView.frame = rect;
}completion:^(BOOL finish){
}];
}
}
Note that my top view initial height is 80 and i want to make it 64 when scroll up and vice versa.
with this code the view height animated but it depends upon animation duration.So if i scroll fast then it is not working properly.The original app i mentioned have very smooth animation. How could i achieve that?
Screen shot of original App-
These screen shots showing three different scroll position, please note the "MySurgery" text on top.1- Larger text and right align.
2- small text and near centre position
3- smaller text and centralised(like navigation bar)
I think you dont need animation for this, you just need some calculations and setting frame of the top view. like,
-(void)scrollViewDidScroll:(UIScrollView *)scrollView
{
CGPoint offset = scrollView.contentOffset;
if (offset.y>0 && offset.y<64) {
[topView layoutIfNeeded];
CGRect viewFrame = topView.frame;
viewFrame.size.height--;
topView.frame = viewFrame;
}
}
Note that layoutIfNeeded is required if your view is using autolayout
I have view with UITableView. Above this list I have UIButton. I need to implement an animation what will move button vertically according to scrolling on list and return to base location when scrolling is finished. I show scrolling down in pictures bellow:
This is not scrolled list:
This is list scrolled to half:
This is list fully scrolled:
For now I detect start and stop scrolling list events and do animation like that:
-(void)scrollViewWillBeginDragging:(UIScrollView *)scrollView
{
CGRect screenRect = [[UIScreen mainScreen] bounds];
CGFloat screenWidth = screenRect.size.width;
CGRect newFrame = button.frame;
newFrame.origin.y = screenHeight - (newFrame.size.height/2.0);
[UIView animateWithDuration:2
animations:^{
button.frame = newFrame;
}];
}
-(void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
CGRect newFrame = storedButtonFrame;
[UIView animateWithDuration:2
animations:^{
button.frame = newFrame;
}];
}
I have few issues with this First is that when I scrolling down my animation is animating to then end and I want to animate based on scrolled list eg. when I scroll down list for 10px I would like to move button only for 10px not to the end of list. Second is that I get stop scroll event when begin scroll animation is still running the start animation is blink to the end and the end animation is start animating what is definitly what I dont want. I dont have to much experiance in iOS and I really dont have any ide how can I do this. Have any idea how can I do something like this?
Instead of using scrollViewWillBeginDragging: you could use scrollViewDidScroll: like so:
/// Animate the button position as the scroll view scrolls
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
CGFloat percentage = scrollView.contentOffset.y / scrollView.contentSize.height;
CGRect frame = _button.frame;
frame.origin.y = scrollView.contentOffset.y + percentage * self.tableView.frame.size.height;
_button.frame = frame;
}
/// Animate the button back to the top-right corner
- (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView
{
CGRect frame = _button.frame;
frame.origin.y = scrollView.contentOffset.y;
[UIView animateWithDuration:0.4f
animations:^{
_button.frame = frame;
}];
}
This makes the button follow the scroll indicator as you scroll the list. scrollViewDidScroll: fires very often so the movement is smooth.
When the list stops, it goes back to its default position at the top-right, which you get from contentOffset.y.
Im building a custom UIView similar to UIPopover view , simply I subclass the UIView class and build the stuff of controls and events inside .. to show this view I assign the superView through My sub Class datasource like this
if ([dataSource respondsToSelector:#selector(containerView)])
superView = [dataSource containerView];
and to show it I have a function doing that like this
- (void) showPopOverFromRect : (CGRect) rect
{
CGSize popSize = self.frame.size;
float yPoint;
if(ntPopOverDirection == NTPopOverArrowDirectionUP)
yPoint = rect.origin.y + 10;
else
yPoint = rect.origin.y - 10;
self.frame = CGRectMake(rect.origin.x - popSize.width, yPoint , popSize.width, popSize.height);
[superView addSubview:self];
}
so My Question .. how can i dismiss this view (remove it) if the user tap AnyWhere on the superView just like the UIPopOverController ?
I suggest that you create your custom UIView to fill the entire superview or the entire screen with a clear background or a radial gradient. Then inside of this you would put another UIView that has the look and feel of the popover.
This eliminates the issue of trying to capture taps and sending notifications from other views. It will be all self contained.
You can easily add a gesture recognizer inside your custom view to close the view when the user touches the clear area.
You could place a UIButton below your new UIView that is clear. When this new button is pressed, it dismisses your view and removes itself from superview.
Something like:
- (void) showPopOverFromRect : (CGRect) rect
{
CGSize popSize = self.frame.size;
float yPoint;
if(ntPopOverDirection == NTPopOverArrowDirectionUP)
yPoint = rect.origin.y + 10;
else
yPoint = rect.origin.y - 10;
self.frame = CGRectMake(rect.origin.x - popSize.width, yPoint , popSize.width, popSize.height);
UIButton *dismissButton = [UIButton buttonWithType:UIButtonTypeCustom];
dismissButton.backgroundColor = [UIColor clearColor];
dismissButton.frame = [[UIScreen mainScreen] bounds];
[dismissButton addTarget:self.delegate action:#selector(dismissPopover) forControlEvents:UIControlEventTouchUpInside];
[superview addSubview:dismissButton];
[superView addSubview:self];
}
You'd have to set up the view to set it's superview as a delegate that receives the message to dismiss the popover, though.
I have a scrollView and inside this scroll view I have 4 images. It's in paging enabled. But I want to do an IBAction that scroll these images random. How can I do?
#define numPages 4
CGRect frame = scrollView.frame;
frame.origin.x = frame.size.width * (arc4random() % (numPages - 1));
frame.origin.y = 0;
[scrollView scrollRectToVisible:frame animated:YES];
it may be useful to you.
every time change the contentoffset
[scrollView contentOffset:CGSizeMake(totalscrollviewwidth,480];
And find this link also