Hi here is what I'm trying to do.
I've got a Table View with transparent cell's background.
cell.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:#"trans.png"]];
And I added to the ViewDidLoad a background image.
- (void)viewDidLoad {
bgView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 480)];
bgView.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:#"homelights.png"]];
[super viewDidLoad];
self.title = #"";
}
So this works fine, I've got a tableView with transparent cells and a background image. Now the plan is when I scroll the TableView down, the image should react and move up.
Any idea how to trigger the scrolldown? Or where to start?
I enabled scrollViewDidScroll;
- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
CGFloat scrollOffset = scrollView.contentOffset.y;
Works like a charm, I can read the scroll position, but when I'm trying to animate UIView, by linking the scrollView.contentOffset.y to the UIView "y" position;
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
CGFloat scrollOffset = scrollView.contentOffset.y;
[UIView beginAnimations:#"UIViewAnimationCurveEaseInOut" context:nil];
bgView.center = CGPointMake(bgView.center.x, bgView.center.y+scrollOffset);
[UIView commitAnimations];
}
So I tried to make the UIView bigger to the original size of the image 640x832 to be able to navigate on it, but doesn't seems to work.
bgView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 640, 832)];
bgView.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:#"homelights.png"]];
Any idea why this is happening?
Your table view is a subclass of UIScrollView and your delegate for the table view is also (automatically) a delegate of the scroll view. Implement the scrollViewDidScroll: delegate method and use it to monitor how the table view has changed and move your background view.
Related
I have tried Adding UIScrollView to a UIViewController, and I can never get my view to move down when I scroll, either on a simulator on a real device. I have also tried increasing the size, so my code is as follows:
+(void)addScrollViewToView:(UIView *)view
{
UIScrollView* scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, view.bounds.size.width * 2, view.bounds.size.height * 2)];
scrollView.backgroundColor = [UIColor clearColor];
scrollView.scrollEnabled = YES;
scrollView.pagingEnabled = YES;
scrollView.showsVerticalScrollIndicator = YES;
scrollView.showsHorizontalScrollIndicator = YES;
scrollView.contentSize = CGSizeMake(view.bounds.size.width * 2, view.bounds.size.height * 2);
[view insertSubview:scrollView atIndex:0];
//[view sendSubviewToBack:scrollView]; - commented out
}
It is called within viewDidLoad like so:
#implementation MyLoginViewController
- (void)viewDidLoad
{
[super viewDidLoad];
[Utils addScrollViewToView:self.view];
self.passwordTextField.secureTextEntry = YES;
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc]
initWithTarget:self
action:#selector(dismissKeyboard)];
[self.view addGestureRecognizer:tap];
} // viewDidLoad method ends here
There is never any response when I try and scroll up with my mouse on a simulator. There is a background image to my view controller that I created using a storyboard. Would changing the index make any difference?
It happen because you add gesture recognizer. Gesture recognizer blocks and not pass your touch.
You can make this for dismiss keyboard with UIScrollView:
+(void)addScrollViewToView:(UIView *)view
{
// your code
scrollView.keyboardDismissMode = UIScrollViewKeyboardDismissModeOnDrag;
}
And remove UITapGestureRecognizer.
Or is it because your frame size is the same as your content size? The scroll view will only scroll if its content is bigger than its frame.
What did the trick was adding the view to the scrollview.
I.e.:
View >
ScrollView >
View that I wanted to scroll
Not:
View that I wanted to scroll >
ScrollView.
I have a UIView which is located offscreen and I'm animating the frame so that the view slides in offscreen from the bottom and is visible. I'd like to simultaneously animate the alpha property of a UILabel on the view as well so it fades in. Unfortunately it appears I can't do the alpha animation because the view is offscreen and doesn't appear to take hold. It looks something like this:
nextCell.titleLabel.alpha = 0;
[UIView animateWithDuration:collapsedAnimationDuration animations:^{
CGRect newFrame = lastCell.frame;
newFrame.origin = CGPointMake(lastCell.frame.origin.x , lastCell.frame.origin.y + THREAD_CELL_HEIGHT);
nextCell.frame = newFrame;
nextCell.titleLabel.alpha = 1;
}];
Is it not possible to start animating the alpha of the subview because it's offscreen? If I position the view on screen and then try the animation it looks great but that's not the effect I'm going for. Thanks for your help.
Is this code executed in cellForRowAtIndexPath? If so, try moving it to tableView:willDisplayCell:forRowAtIndexPath:. The table view resets various properties of the cell before displaying it.
From the AppDelegate didFinishLaunching method:
self.myView = [[MyView alloc] initWithFrame:CGRectMake(320, 480, 400, 400)];
self.myView.titleLabel.text = #"test text";
self.myView.titleLabel.alpha = 0;
[UIView animateWithDuration:10.0 animations:^{
CGRect newFrame = self.myView.frame;
newFrame.origin = CGPointMake(0 , 0);
self.myView.frame = newFrame;
self.myView.titleLabel.alpha = 1;
}];
[self.viewController.view addSubview:self.myView];
MyView is just this:
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code
[self addSubview:self.titleLabel];
}
return self;
}
- (UILabel *)titleLabel
{
if (!_titleLabel) {
_titleLabel = [[UILabel alloc] initWithFrame:CGRectMake(0, 0, 200, 200)];
}
return _titleLabel;
}
I did no important changes to the code you presented and it worked fine. So assuming you're not doing what Tim mentioned (it won't work if you're doing it), we need more details to help you out.
I have a UIScrollView with a UIView inside it, in side the UIView I made a button to add textLabels to it.
and ideally I would want a really big canvas and be able to put text on it and pan and zoom around. however with the UIScrollView it does zoom, but does not pan at all
It seems that when I remove the UIView that i add inside the UIScrollView it works fine.
heres viewDidLoad:
[super viewDidLoad];
CGFloat mainViewWidth = 700;
CGFloat mainViewHeight = 500;
//scrollView.contentSize = CGSizeMake(scrollView.frame.size.width * kNumberOfPages, scrollView.frame.size.height * kNumberOfPages);
//self.mainScrollView.bounds = CGRectMake(0., 0., 3000, 3000);
self.mainScrollView.scrollsToTop = NO;
self.mainScrollView.delegate = self;
self.mainScrollView.maximumZoomScale = 50.;
self.mainScrollView.minimumZoomScale = .1;
self.mainScrollView.autoresizingMask = UIViewAutoresizingFlexibleHeight;
self.mainView = [[UIView alloc] initWithFrame: CGRectMake(0, 0, mainViewWidth, mainViewHeight)];
[self.mainView setUserInteractionEnabled:NO];
self.mainView.backgroundColor = [[UIColor alloc] initWithRed:0.82110049709463495
green:1
blue:0.95704295882687884
alpha:1];
[self.mainScrollView setContentSize:CGSizeMake(5000, 5000)];
[self.mainScrollView insertSubview:self.mainView atIndex:0];
Edit:
Heres the all I have for UIScrollViewDelegate
#pragma mark - Scroll View Delegate
- (void)scrollViewDidScroll:(UIScrollView *)sender {
}
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView
{
//
return self.mainView;
}
- (void)scrollViewDidEndZooming:(UIScrollView *)zoomedScrollView withView:(UIView *)view atScale:(float)scale
{
}
I just went through this exact same dilemma.
My UIScrollView exists within the storyboard, and if I add a UIView (containerView) within that storyboard to the UIScrollView, the image fails to pan. And all sorts of other centering weirdness occurs too.
But if I do it through code:
// Set up the image we want to scroll & zoom
UIImage *image = [UIImage imageNamed:#"plan-150ppi.jpg"];
self.imageView = [[UIImageView alloc] initWithImage:image];
self.containerView = [[UIView alloc] initWithFrame:self.imageView.frame];
[self.containerView addSubview:self.imageView];
[self.scrollView addSubview:self.containerView];
// Tell the scroll view the size of the contents
self.scrollView.contentSize = self.containerView.frame.size;
... then it works just fine.
My UIScrollView is not setting its contentOffset when using zoomToRect.
I have an UIScrollView with an UIImageView inside. Scrolling and zooming itself is working so far. Now I want to give the scrollview at app start a certain zoomed rect of the image view. For this I implemented zoomToRect: and it is setting the zoomsScale correctly, but it does not set the contentOffset.
Expected outcome when using zoomToRect is that the UIScrollView zooms in or out according to the selected rect and set its contentOffset according to the origin coordinates of the rect given to the zoomToRect method.
The actual behaviour is that it zooms to the correct zoomScale but my UIImageView is always at the origin 0,0 and not the expected origin of the x (475) and y (520) coordinated of the rect I specified in zoomToRect.
My images size is 1473x1473.
Here is some the code
- (void)viewDidLoad {
CGRect bounds = self.view.frame;
_imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"bgImage.png"]];
self.containerView = [[UIView alloc] initWithFrame:bounds];
_containerView.contentMode = UIViewContentModeCenter;
_scrollView = [[UIScrollView alloc] initWithFrame:bounds];
_scrollView.delegate = self;
_scrollView.contentSize = _imageView.bounds.size;
_scrollView.minimumZoomScale = 0.2;
[_scrollView addSubview:_containerView];
[_containerView addSubview:_imageView];
[self.view addSubview:_scrollView];
}
- (void)viewWillAppear:(BOOL)animated {
[super viewWillAppear:animated];
[_scrollView zoomToRect:CGRectMake(475.0, 150.0, 520.0, 747.0) animated:NO];
}
#pragma mark UIScrollViewDelegate methods
- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView {
return _containerView;
}
- (void)scrollViewDidZoom:(UIScrollView *)scrollView {
[self printVisibleRectToConsole:scrollView];
CGSize newImageViewSizeWithScale = CGSizeMake(_imageView.bounds.size.width * _scrollView.zoomScale,
_imageView.bounds.size.height * _scrollView.zoomScale);
_scrollView.contentSize = newImageViewSizeWithScale;
}
My questions:
Why does zoomToRect does not set the contentOffset?
How can I get zoomToRect to change my contentOffset as expected?
The problem is that the view you're zooming (containerView) is not as big as the image view it contains (and which you actually want to zoom). Its frame is set to the frame of the view controller. You don't see this because a UIView doesn't clip its subviews by default.
You should initialize containerView with the bounds of your image view instead.
self.containerView = [[UIView alloc] initWithFrame:_imageView.bounds];
In my app, I have a split screen in which the detail view is a scrollview. I have 5 tables which are subviews of my scrollview in which 3 table views are side by side on top and 2 table views are side by side on bottom
I have already implemented a way in which when I click any of the rows of any of the table in the scrollview, that view disappears and another view zooms into its position.
I write the following code in the didSelectRowAtIndexPath in the middle table subview,
CGFloat xpos = self.view.frame.origin.x;
CGFloat ypos = self.view.frame.origin.y;
self.view.frame = CGRectMake(xpos+100,ypos+150,5,5);
[UIView beginAnimations:#"Zoom" context:NULL];
[UIView setAnimationDuration:2];
self.view.frame = CGRectMake(xpos,ypos,220,310);
[UIView commitAnimations];
[self.view addSubview:popContents.view];
popContents is the view I need to zoom into to the view previously occupied by that particular table view and that happens correctly.
However the problem that I am facing is that since there is another table subview in the side, if I increase the frame size to say 250 or so, the part of the zoomed in view gets hidden by the tableview on the side ( as its as if a part of the zoomed in view goes under the tableview on the side).
Is there anyway to correct this so that my zoomed in view would not get hidden by the tableviews on its sides?
I hope I have explained my problem correctly...
UPDATE:
Here is the code I am using for adding the subviews for the scrollview
// Scroll view
scrollView = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 30, 1000, 740)];
scrollView.contentSize = CGSizeMake(1000, 700);
scrollView.delegate = self;
scrollView.scrollEnabled = YES;
scrollView.showsHorizontalScrollIndicator = YES;
scrollView.backgroundColor = [UIColor scrollViewTexturedBackgroundColor];
[self.view addSubview:scrollView];
aView = [[aViewController alloc] initWithNibName:#"aViewController" bundle:nil];
aView.view.frame = CGRectMake(10, 25, 220, 310);
[aView loadList:objPatients];
[scrollView addSubview:aView.view];
bView = [[bViewController alloc] initWithNibName:#"bViewController" bundle:nil];
bView.view.frame = CGRectMake(10, 350, 220, 310);
[bView loadList:objPatients];
[scrollView addSubview:bView.view];
cView = [[cViewController alloc] initWithNibName:#"cViewController" bundle:nil];
cView.view.frame = CGRectMake(240, 25, 220, 310);
[cView loadList:objPatients];
[scrollView addSubview:cView.view];
dView = [[dViewController alloc] initWithNibName:#"dViewController" bundle:nil];
enView.view.frame = CGRectMake(240, 350, 220, 310);
[enView loadList:objPatients];
[scrollView addSubview:dView.view];
eView = [[eViewController alloc] initWithNibName:#"eViewController" bundle:nil];
eView.view.frame = CGRectMake(470, 25, 220, 310);
[eView loadList:objPatients];
[scrollView addSubview:eView.view];
say for example, I add the code for didSelectRowAtIndexPath in cViewController subview...
This is a guess since I would need to know how your table views are added to the scroll view, but the middle table view was probably added before the one on the side. Views are "stacked" in the order they're added with the last one on top. You'll need to get the scroll view to move the middle view to the front with this method
- (void)bringSubviewToFront:(UIView *)view
The best way to do that would be to create a protocol for the table views and make the scroll view the delegate. The method would be something like this
- (void) moveAViewToFront: (MyTableView *) aTableView
{
[self.view bringSubviewToFront: aTableView.view];
}
You would then call the delegate method before setting up the animation.
Edited
After a little more thought I realized that the subviews have a reference to their superview so this bit of code should provide an idea on how to solve the problem. I created a test app which has a view controller which adds two sub views. The view controller header file is MoveSubviewViewController.h
#import <UIKit/UIKit.h>
#interface MoveSubviewViewController : UIViewController
{
}
#end
and it's implementation is
#import "MoveSubviewViewController.h"
#import "MoveableSubview.h"
#implementation MoveSubviewViewController
- (void)viewDidLoad
{
[super viewDidLoad];
// Create two overlapping subviews. The blue subview will start at the top of
// the frame and extend down two thirds of the frame.
CGRect superviewFrame = self.view.frame;
CGRect view1Frame = CGRectMake( superviewFrame.origin.x, superviewFrame.origin.y,
superviewFrame.size.width, superviewFrame.size.height * 2 / 3);
MoveableSubview *view1 = [[MoveableSubview alloc] initWithFrame: view1Frame];
view1.backgroundColor = [UIColor blueColor];
[self.view addSubview: view1];
[view1 release];
// The green subview will start one third of the way down the frame and
// extend all the to the bottom.
CGRect view2Frame = CGRectMake( superviewFrame.origin.x,
superviewFrame.origin.y + superviewFrame.size.height / 3,
superviewFrame.size.width, superviewFrame.size.height * 2 / 3);
MoveableSubview *view2 = [[MoveableSubview alloc] initWithFrame: view2Frame];
view2.backgroundColor = [UIColor greenColor];
[self.view addSubview: view2];
[view2 release];
}
#end
The subview class is MoveableSubview with another simple header
#import <UIKit/UIKit.h>
#interface MoveableSubview : UIView
{
}
#end
and implementation
#import "MoveableSubview.h"
#implementation MoveableSubview
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
// Move this view to the front in the superview.
[self.superview bringSubviewToFront: self];
}
#end
The thing to do is to add the
[self.superview bringSubviewToFront: self];
line before setting up the animation.