I want to show 4 different animations inside UIScrollView in one time, all of them has 200+ frames, so I think that the best solution to solve this is to show videos. It costs less memory then animations. My videos are ~ 500x300 dimensions, and I want to show them as 250x150. How can I do this ?
this must be the solution of your problem
- (void)layoutScrollImages
{
UIView *view = nil;
NSArray *subviews = [self.scrollView subviews];
// reposition all image subviews in a horizontal serial fashion
CGFloat curXLoc = 0;
for (view in subviews)
{
if ([view isKindOfClass:[UIView class]] && view.tag > 0)
{
CGRect frame = view.frame;
frame.origin = CGPointMake(curXLoc, 0);
view.frame = frame;
curXLoc += (kScrollObjWidth);
}
}
// set the content size so it can be scrollable
//[self.scrollView setContentSize:CGSizeMake((numImages * kScrollObjWidth), [self.scrollView bounds].size.height)];
[self.scrollView setContentSize:CGSizeMake((numImages * kScrollObjWidth), kScrollObjHeight)];
}
Related
I'm currently setting up a UIScrollView with the following structure
UIScrollView
--ContentView (UIView)
--ContainerView1 (UIView)
--UILabel1
--UILabel2
--ContainerView2 (UIView)
--UILabel3
--UILabel4
--ContainerView3 (UIView)
--UILabel5
--UILabel6
I've pinned all the four edges for all the elements above and also have defined their height constraints (Storyboard complaints of zero height if I didn't do so).
Now whenever my UILabel receives its text from the server, I call sizeToFit for all the labels. Then I use the lastObject of the containerViews to calculate the supposing new height. Then I call setNeedsLayout. However, nothing changes in my app!
This is the code that I use to calculate the new height and adjust. Perhaps have I programmed it wrong? Sorry my concept on constraints is not strong, may have set the constraints the wrong way too?
- (void) relayoutAllSubViews: (NSArray *) arrayOfContainerViews
{
//Relayout subviews
for (int i = 0; i < [arrayOfContainerViews count]; i++)
{
UIView * indView = [arrayOfContainerViews objectAtIndex:i];
if (indView.hidden == YES)
{
indView.frame = CGRectMake(indView.frame.origin.x, indView.frame.origin.y, indView.frame.size.width, 0);
}
else
{
UIView * lastSubviewInView = [indView.subviews lastObject];
CGFloat subviewEndPos = lastSubviewInView.frame.origin.y + lastSubviewInView.frame.size.height;
if ((subviewEndPos - (indView.frame.origin.y + indView.frame.size.height)) > 0)
{
indView.frame = CGRectMake(indView.frame.origin.x, indView.frame.origin.y, indView.frame.size.width, (subviewEndPos - indView.frame.origin.y));
}
}
}
//Adjust scrollview
UIView * lastView = [self.scrollView.subviews lastObject];
CGFloat newEndPos = lastView.frame.origin.y + lastView.frame.size.height;
self.contentView.bounds = CGRectMake(self.contentView.bounds.origin.x, self.contentView.bounds.origin.y, self.contentView.bounds.size.width, (newEndPos - self.contentView.bounds.origin.y));
self.scrollView.contentSize = self.contentView.bounds.size;
[self.view setNeedsLayout];
}
Need Help!!
//use the below code to set the content size of a scroll view.
float newHeight=0.0f;
for(UIView *subViews in [scrollViewObj subviews])
{
if([subViews isKindOfClass:[UIView class]])
{
newHeight=newHeight+(subViews.frame.origin.x+subViews.frame.size.height);
}
}
NSLog(#"%f",newHeight);
[scrollView setContentSize:CGSizeMake(300, newHeight)];//change the width as you need
//i have added code for dynamically adding the subview heights
float newHeight=0.0f;
for(UIView *subViews in [scrollViewObj subviews])
{
if([subViews isKindOfClass:[UIView class]])
{
if([[subViews subviews] count]>0)
{
float heightOfSubviews=0.0f;
for(UIView *insideSubViews in [subViews subviews])
{
heightOfSubviews=heightOfSubviews+(insideSubViews.frame.origin.y+insideSubViews.frame.size.height);
}
NSLog(#"%f",heightOfSubviews);
[subViews setFrame:CGRectMake(subViews.frame.origin.x, subViews.frame.origin.y, subViews.frame.size.width, heightOfSubviews)];
}
}
}
UIView *viewLastObj=scrollViewObj.subviews.lastObject;
newHeight=viewLastObj.frame.origin.y+viewLastObj.frame.size.height;
NSLog(#"%f",newHeight);
[scrollViewObj setContentSize:CGSizeMake(300, newHeight)];
I have a UIScrollView with a number of rectangular subviews lined up, of equal sizes. Then I need to be able to pass a CGPoint to that UIScrollView and I want it to give me the rectangular subview that contains the CGPoint. That's basically hitTest:event, except hitTest:event: doesn't work with UIScrollView once CGPoint goes beyond the UIScrollView bounds and doesn't look into its actual content.
What's everyone been doing about this? How to "hit test" on a UIScrollView content view?
Here's some code to illustrate the problem:
NSArray *rectangles = [self getBeautifulRectangles];
CGFloat rectangleLength;
rectangleLength = 100;
// add some rectangle subviews
for (int i = 0; i < rectangles.count; i++) {
UIView *rectangle = [rectangles objectAtIndex:i];
[rectangle setFrame:CGRectMake(i * rectangleLength, 0, rectangleLength, rectangleLength)];
[_scrollView addSubview:rectangle];
}
[_scrollView setContentSize:CGSizeMake(rectangleLength * rectangles.count, rectangleLength)];
// add scroll view to parent view
UIView *containerView = [[UIView alloc] initWithFrame:CGRectMake(0,0,320, rectangleLength)];
[containerView addSubview:_scrollView];
// compute CGPoint to center of first rectangle
CGPoint number1RectanglePoint = CGPointMake(0 * rectangleLength + 50, 50);
// compute CGPoint to center of fifth rectangle
CGPoint number5RectanglePoint = CGPointMake(4 * rectangleLength + 50, 50);
UIView *firstSubview = [containerView hitTest:number1RectanglePoint withEvent:nil];
UIView *fifthSubview = [containerView hitTest:number5RectanglePoint withEvent:nil];
if (firstSubview) NSLog(#"first rectangle OK");
if (fifthSubview) NSLog(#"fifth rectangle OK");
output: first rectangle OK
You should be able to loop through the scrollview subviews
+(UIView *)touchedViewIn:(UIScrollView *)scrollView atPoint:(CGPoint)touchPoint {
CGPoint actualPoint = CGPointMake(touchPoint.x + scrollView.contentOffset.x, scrollView.contentOffset.y + touchPoint.y);
for (UIView * subView in scrollView.subviews) {
if(CGRectContainsPoint(subView.frame, actualPoint)) {
NSLog(#"THIS IS THE ONE");
return subView;
}
}
//Nothing touched
return nil;
}
I guess you pass the wrong CGPoint coordinate to the hitTest:withEvent: method causing wrong behavior if the scroll view is scrolled.
The coordinate you pass to this method must be in the target views coordinate system. I guess your coordinate is in the UIScrollView's superview's coordinate system.
You can convert the coordinate prior to using it for the hit test using CGPoint hitPoint = [scrollView convertPoint:yourPoint fromView:scrollView.superview].
In your example you let the container view perform the hit testing, but the container can only see & hit the visible portion of the scroll view and thus your hit fails.
In order to hit subviews of the scroll view which are outside of the visible area you have to perform the hit test on the scroll view directly:
UIView *firstSubview = [_scrollView hitTest:number1RectanglePoint withEvent:nil];
UIView *fifthSubview = [_scrollView hitTest:number5RectanglePoint withEvent:nil];
I Want to implement a scrollview that has several UIViews inside of it. The left-most item needs to be larger than the rest of the items. So my problem is this. Whenever an item is leaving the screen to the left (its origin.x is less than 15), I need to scale the item down from 470x440 to 235x220 pixels. This is fairly simple to implement. The problem is that the item that is moved to the left of pixel 480 needs to be zoomed in from 235x220 pixels to 470x440 pixels AND it needs to be moved to the left by 235 pixels (so as to not cover the item to its right, but rather move into the space that the leaving element left when it "shrunk".
I have tried a few different approaches to this, but I cannot the the animation to look good, and there is a bunch of glitches here and there.
Does anyone have any idea how I might go about implementing this type of feature ? Note that I do not want to zoom, but I want to resize the elements inside the scroll view in such a way that the left-most element (that is visible on the screen) is double the size of the other elements.
In case anyone else might be interested, I ended up with the following inside scrollViewDidScroll:
- (void)scrollViewDidScroll:(UIScrollView *)scrollView {
float contentOffset = scrollView.contentOffset.x;
int leavingElementIndex = [_scrollView indexOfElementLeavingScene:scrollView.contentOffset.x];
int entereingElementIndex = leavingElementIndex + 1;
if (leavingElementIndex >= 0 && contentOffset > 0) {
CGRect leavingFrame = [[[scrollView subviews] objectAtIndex:leavingElementIndex] frame];
CGRect enteringFrame = [[[scrollView subviews] objectAtIndex:entereingElementIndex] frame];
float scalePerentage = (contentOffset - (_scrollView.smallBoxWidth * leavingElementIndex))/(_scrollView.smallBoxWidth);
enteringFrame.size.width = _scrollView.smallBoxWidth + (_scrollView.smallBoxWidth * scalePerentage);
enteringFrame.size.height = _scrollView.smallBoxHeight + (_scrollView.smallBoxHeight * scalePerentage);
enteringFrame.origin.x = [_scrollView leftMostPointAt:entereingElementIndex] - (_scrollView.smallBoxWidth * scalePerentage);
[[[scrollView subviews] objectAtIndex:entereingElementIndex] setFrame:enteringFrame];
leavingFrame.size.width = _scrollView.largeBoxWidth - (_scrollView.smallBoxWidth * scalePerentage);
leavingFrame.size.height = _scrollView.largeBoxHeight - (_scrollView.smallBoxHeight * scalePerentage);
[[[scrollView subviews] objectAtIndex:leavingElementIndex] setFrame:leavingFrame];
//Reset the other visible frames sizes
int index = 0;
for (UIView *view in [scrollView subviews]) {
if([view isKindOfClass:[SlidingView class]] && index > entereingElementIndex) {
CGRect frame = view.frame;
frame.size.width = _scrollView.smallBoxWidth;
frame.size.height = _scrollView.smallBoxHeight;
frame.origin.x = [_scrollView leftMostPointAt:index];
[view setFrame:frame];
}
index++;
}
}
}
This is what it looks like in the end:
End Result http://stuff.haagen.name/iOS%20scroll%20resize.gif
I have a UIScrollView with paging enabled with multiple subviews on the page: a UIButton, UIwebview and UIImageView. Both the webview and the image change on every page. This works fine. I used Apples scrolling image paging example to get me started.
But when I add a second UIImageView, the position of image I have in place already gets the new values and the new image doesn't display.
This is the code inside viewdidload for the first image (works fine):
// load all the images from our bundle and add them to the scroll view
for (i = 1; i <= kNumImages; i++)
{
NSString *imageName = [NSString stringWithFormat:#"image%d.jpg", i];
UIImage *image2 = [UIImage imageNamed:imageName];
UIImageView *imageView2 = [[UIImageView alloc] initWithImage:image2];
// setup each frame to a default height and width, it will be properly placed when we call "updateScrollList"
CGRect rect = imageView2.frame;
rect.size.height = imageviewScrollObjHeight;
rect.size.width = imageviewScrollObjWidth;
// Get the Layer of any view
CALayer * imageLayer = [imageView2 layer];
[imageLayer setMasksToBounds:YES];
[imageLayer setCornerRadius:7.0];
// You can even add a border
[imageLayer setBorderWidth:1.0];
[imageLayer setBorderColor:[[UIColor lightGrayColor] CGColor]];
imageView2.frame = rect;
imageView2.tag = i; // tag our images for later use when we place them in serial fashion
[scrollView1 addSubview:imageView2];
}
[self layoutScrollImages]; // now place the photos in serial layout within the scrollview
This is the code to layout the first image on every page, different image per page(outside viewdidload)(works fine):
// layout images for imageview1
- (void)layoutScrollImages
{
UIImageView *imageView = nil;
NSArray *subviews = [scrollView1 subviews];
// reposition all image subviews in a horizontal serial fashion
CGFloat curXLoc = 10;
for (imageView in subviews)
{
if ([imageView isKindOfClass:[UIImageView class]] && imageView.tag > 0)
{
CGRect frame = imageView.frame;
frame.origin = CGPointMake(curXLoc, 50);
imageView.frame = frame;
curXLoc += (kScrollObjWidth);
}
}
// set the content size so it can be scrollable
[scrollView1 setContentSize:CGSizeMake((kNumImages * kScrollObjWidth), [scrollView1 bounds].size.height)];
}
This is the code for the second image (inside viewdidload): (when i remove [self layoutNavScrollImages]; the image loads only on the first page)
for (i = 1; i <= kNumImages; i++)
{
UIImage *navBarImage = [UIImage imageNamed:#"navigationbar.png"];
UIImageView *imageViewNavBar = [[UIImageView alloc] initWithImage:navBarImage];
// setup each frame to a default height and width, it will be properly placed when we call "updateScrollList"
CGRect navBarRect = imageViewNavBar.frame;
navBarRect.size.height = 44;
navBarRect.size.width = 320;
navBarRect.origin.x = 0;
navBarRect.origin.y = 0;
/* Get the Layer of any view
CALayer * imageLayer = [imageView3 layer];
[imageLayer setMasksToBounds:YES];
[imageLayer setCornerRadius:7.0];
// You can even add a border
[imageLayer setBorderWidth:1.0];
[imageLayer setBorderColor:[[UIColor lightGrayColor] CGColor]];
*/
imageViewNavBar.frame = navBarRect;
imageViewNavBar.tag = i; // tag our images for later use when we place them in serial fashion
[scrollView1 addSubview:imageViewNavBar];
}
[self layoutNavScrollImages];
And the code outside viewdidload:(this overwrites the position of the first image)
- (void)layoutNavScrollImages
{
UIImageView *view = nil;
NSArray *subviews = [scrollView1 subviews];
// reposition all image subviews in a horizontal serial fashion
CGFloat curXLoc = 0;
for (view in subviews)
{
if ([view isKindOfClass:[UIImageView class]] && view.tag > 0)
{
CGRect frame = view.frame;
frame.origin = CGPointMake(curXLoc, 0);
view.frame = frame;
curXLoc += (kScrollObjWidth);
}
}
// set the content size so it can be scrollable
[scrollView1 setContentSize:CGSizeMake((kNumImages * kScrollObjWidth), [scrollView1 bounds].size.height)];
}
The way to do this is to make one (big) UIView and add every UIImageView as a subview of that UIView. And then add the UIView as a subview to UIScrollView.
[totalView addSubview:imageView1];
[totalView addSubview:imageView2;
[totalView addSubview:buttonView1];
[totalView addSubview:buttonView2];
[totalView addSubview:webView];
[scrollView addSubview:totalView];
Be sure to set the right content size or scrollview wont work:
[scrollView setContentSize:CGSizeMake((320*kNumImages), 411)];
Setup views and tag the UIView (inside viewdidload):
NSUInteger i;
for (i = 1; i <= kNumImages; i++)
{
//... code to setup views
totalView.tag = i;
}
[self layoutViews]; // now place the views in serial layout within the scrollview
Then to layout the view on every page:
- (void)layoutViews
{
UIView *view = nil;
NSArray *subviews = [scrollView subviews];
// reposition all image subviews in a horizontal serial fashion
CGFloat curXLoc = 0;
for (view in subviews)
{
if ([view isKindOfClass:[UIView class]] && view.tag > 0)
{
CGRect frame = view.frame;
frame.origin = CGPointMake(curXLoc, 0);
view.frame = frame;
curXLoc += (kScrollObjWidth);
}
}
}
I hope this is as clear as possible. If anyone thinks this is not the right way to do it please comment.
I have this code for a scrollview to showe 3 images:
const CGFloat kScrollObjHeight = 150.0;
const CGFloat kScrollObjWidth = 320.0;
const NSUInteger kNumImages = 3;
- (void)layoutScrollImages
{
UIImageView *view = nil;
NSArray *subviews = [scrollView1 subviews];
// reposition all image subviews in a horizontal serial fashion
CGFloat curXLoc = 0;
for (view in subviews)
{
if ([view isKindOfClass:[UIImageView class]] && view.tag > 0)
{
CGRect frame = view.frame;
frame.origin = CGPointMake(curXLoc, 0);
view.frame = frame;
curXLoc += (kScrollObjWidth);
}
}
// set the content size so it can be scrollable
[scrollView1 setContentSize:CGSizeMake((kNumImages * kScrollObjWidth), [scrollView1 bounds].size.height)];
}
- (void)viewDidLoad
{
self.view.backgroundColor = [UIColor viewFlipsideBackgroundColor];
// 1. setup the scrollview for multiple images and add it to the view controller
//
// note: the following can be done in Interface Builder, but we show this in code for clarity
[scrollView1 setBackgroundColor:[UIColor blackColor]];
[scrollView1 setCanCancelContentTouches:NO];
scrollView1.indicatorStyle = UIScrollViewIndicatorStyleWhite;
scrollView1.clipsToBounds = YES; // default is NO, we want to restrict drawing within our scrollview
scrollView1.scrollEnabled = YES;
// pagingEnabled property default is NO, if set the scroller will stop or snap at each photo
// if you want free-flowing scroll, don't set this property.
scrollView1.pagingEnabled = YES;
scrollView2.pagingEnabled = YES;
scrollView3.pagingEnabled = YES;
// load all the images from our bundle and add them to the scroll view
NSUInteger i;
for (i = 1; i <= kNumImages; i++)
{
NSString *imageName = [NSString stringWithFormat:#"image%d.jpg", i];
UIImage *image = [UIImage imageNamed:imageName];
UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
// setup each frame to a default height and width, it will be properly placed when we call "updateScrollList"
CGRect rect = imageView.frame;
rect.size.height = kScrollObjHeight;
rect.size.width = kScrollObjWidth;
imageView.frame = rect;
imageView.tag = i; // tag our images for later use when we place them in serial fashion
[scrollView1 addSubview:imageView];
//[scrollView2 addSubview:imageView];
//[scrollView3 addSubview:imageView];
[imageView release];
}
[self layoutScrollImages]; // now place the photos in serial layout within the scrollview
}
But now I want to do a scrollview that when is in last image show me after the first image of scroll view and the same thing when I have the first image if I go back, it must show the last image; so I want create a paging loop.
The basic idea is to set yourself as a UIScrollViewDelegate and apply some modulo arithmetic to the scroll position in order to wrap it around.
There are two basic variations on the idea. Suppose your images are A, B, C, so you currently have them within the scrollview ordered as ABC.
In the more logically pleasing solution — especially if you had lots and lots of images — you watch the scroll position and as soon as it gets to a position where the view is being pushed rightward and C has left the screen, you reorder the images as CAB and shift the current scroll position one spot to the right so that the move is invisible to the user. To put that another way, the scroll position is restrained to an area of two screens, centred on the middle of B (so, you get all of B and half a screen either side). Whenever you wrap it from somewhere on the left to somewhere on the right you shift all your image views one place to the right. And vice versa.
In the slightly easier to implement variation, instead of creating a scroll view with images arranged ABC, arrange then as CABCA. Then apply the same wrap around logic but to a central area of four screens and don't do any view reshuffling.
Make sure you use just setContentOffset: (or the dot notation, as in scrollView.contentOffset =) as a setter. setContentOffset:animated: will negate velocity.