Rotate square imageView in ScrollView - iphone

I have a gallery of UIImageViews (that are SQUARE) declared as subviews of UIScrollView:
int size = self.view.frame.size.width/number;
int maxSize = [list count]; //amount of images to show in this view
imageViewArray = [[NSMutableArray alloc] init];
for (int i=0,j=1,k=0; i<maxSize; i++, j++){
UIImageView *imageView = [[UIImageView alloc] initWithImage:[list objectAtIndex:i]];
if (i % number == 0)
{
j = 1;
k++;
}
imageView.frame = CGRectMake((size*(j-1)), (size*(k-1)), size, size);
imageView.contentMode = UIViewContentModeScaleAspectFit;
[imageView setAutoresizingMask: UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleRightMargin | UIViewAutoresizingFlexibleWidth];
[imageScrollView addSubview:imageView];
imageScrollView.contentSize = CGSizeMake(size*number, size*(maxSize/number));
[imageScrollView setAutoresizesSubviews:YES];
In portrait mode everything is ok. However in landscape i want my images to become bigger both in axe X and Y. With pasted code my images get larger frame only in width, so they are wide and short. I want them to keep their ratio, so still to be square. Any idea..?
BTW: I tried to setAutoresizingMask to flexible height,top and bottom, but it makes my UIImages even shorter (i dont know why).

You don't want your margins to be flexible, leave them fixed, you only want the internal height/width to be flexible. So try setting only the following two:
[imageView setAutoresizingMask: UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth];

You wrote that the images should increase in size in landscape view, so where are you adjusting the UIImageViews frames? (And if they are getting smaller, then you have a bug in that missing piece of code.)
And #gamozzii is correct, you want the autoresizing on the imageviews to be:
imageView.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;

Related

Horizontal UIScrollView and hundreds of thumbnail images in iOS?

I need to create a horizontal UIScrollView which to hold hundreds of thumbnail images, just like a slide of thumbnails.
For example, there will be 10 thumbnails showing in a single screen, each of them are horizontally adjacent to each other.
My problem is that I don't know how to make a horizontal UIScrollView to hold the multiple thumbnails which showing at the same time ?
A sample photo is as below. See the bottom part of the screen.
Thanks.
You can add all the thumbnails programatically to your scrollview and use the setContentSize method of UIScrollView. you have to pass 2 values in contentOffset. 1 for width and 1 for height. Please follow link to explore more on this. If you need further help please leave a comment.
Hope it helps.
Please consider Following example.
- (void)setupHorizontalScrollView
{
scrollView.delegate = self;
[self.scrollView setBackgroundColor:[UIColor blackColor]];
[scrollView setCanCancelContentTouches:NO];
scrollView.indicatorStyle = UIScrollViewIndicatorStyleWhite;
scrollView.clipsToBounds = NO;
scrollView.scrollEnabled = YES;
scrollView.pagingEnabled = YES;
NSUInteger nimages = 0;
NSInteger tot=0;
CGFloat cx = 0;
for (; ; nimages++) {
NSString *imageName = [NSString stringWithFormat:#"image%d.jpg", (nimages + 1)];
UIImage *image = [UIImage imageNamed:imageName];
if (tot==15) {
break;
}
if (4==nimages) {
nimages=0;
}
UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
CGRect rect = imageView.frame;
rect.size.height = 40;
rect.size.width = 40;
rect.origin.x = cx;
rect.origin.y = 0;
imageView.frame = rect;
[scrollView addSubview:imageView];
[imageView release];
cx += imageView.frame.size.width+5;
tot++;
}
self.pageControl.numberOfPages = nimages;
[scrollView setContentSize:CGSizeMake(cx, [scrollView bounds].size.height)];
}
I suggest you to look at nimbus
Check out bjhomer's HSImageSidebarView project. It lets you load a scrollview horizontally or vertically and load in the images. Super easy to implement.
First of all, at storyboard drag and drop the scroll view and make the outlet of scrollview named scrollView. Two array one is mutable and one is immutable.
#property(nonatomic,strong)IBOutlet UIScrollView *scrollView;
#property(nonatomic,strong)NSMutableArray *images;
#property(nonatomic,strong)NSArray *imagesName;
The immutable array only store the images which we want to show on the scroll view.Make sure UIscrollview delegate is defined.
In viewcontoller.m file in didload function do following code:
imagesName = [[NSArray alloc]initWithObjects:#"centipede.jpg",#"ladybug.jpg",#"potatoBug.jpg",#"wolfSpider.jpg", #"ladybug.jpg",#"potatoBug.jpg",#"centipede.jpg",#"wolfSpider.jpg",nil];
// mutable array used to show the images on scrollview dynamic becaus after one
// image when scroll other will come
images = [[NSMutableArray alloc]init];
scrollView.delegate = self;
scrollView.scrollEnabled = YES;
int scrollWidth = 120;
scrollView.contentSize = CGSizeMake(scrollWidth,80);
int xOffset = 0;
//the loop go till all images will load
for(int index=0; index < [imagesName count]; index++)
{
UIImageView *img = [[UIImageView alloc] init];
// make the imageview object because in scrollview we need image
img.frame = CGRectMake(5+xOffset, 0, 160, 110);
// the offset represent the values, used so that topleft for each image will
// change with(5+xOffset, 0)and the bottomright(160, 110)
NSLog(#"image: %#",[imagesName objectAtIndex:index]);
img.image = [UIImage imageNamed:[imagesName objectAtIndex:index]];
// The image will put on the img object
[images insertObject:img atIndex:index];
// Put the img object at the images array which is mutable array
scrollView.contentSize = CGSizeMake(scrollWidth+xOffset,110);
//scroll view size show after 125 width the scroll view enabled
[scrollView addSubview:[images objectAtIndex:index]];
// set images on scroll view
xOffset += 170;
}
You can calculate content size width of the scrollview as width = number of images * size of each image. Then set contentSize of the scrollview to this width and the height that you want (scrollView.contentSize = CGSizeMake(width, height))

UIScrollView Rotation Issues

I have a scrollview that automatically generates a series of subviews containing imageviews. The concept is that it's pretty much a custom PDF style reader, where each page is loaded in to an imageview as an image. There are three "layers" - the outer UIScrollView, the automatically generated subViews and the imageview inside the subview.
I've been having some trouble with this, I've asked the question previously, but unfortunately, the core of my question was in the wrong place. Here is my second attempt:
On rotate, everything is rotated as needed. Unfortunately, this is what I'm getting:
Obviously, I would like Image 1 to be centred and for there to be no hint of image 2 until you flick the view across.
Here is my code for setting up the view:
- (void)loadView {
[self setUpView];
}
- (void)setUpView {
//INITIALISE PAGING SCROLL VIEW
CGRect pagingScrollViewFrame = [[UIScreen mainScreen] bounds];
pagingScrollViewFrame.origin.x -= 10;
pagingScrollViewFrame.size.width += 20;
pagingScrollView = [[UIScrollView alloc] initWithFrame:pagingScrollViewFrame];
pagingScrollView.contentMode = UIViewContentModeScaleAspectFit;
//CONFIGURE PAGING SCROLL VIEW
pagingScrollView.pagingEnabled = YES;
pagingScrollView.backgroundColor = [UIColor blackColor];
pagingScrollView.contentSize = CGSizeMake(pagingScrollViewFrame.size.width*7, pagingScrollViewFrame.size.height);
//ACTIVATE PAGING SCROLL VIEW
self.view = pagingScrollView;
//ADD PAGES TO SCROLL VIEW
for (int i = 0; i < 7; i++){
ImageScrollView *page = [[[ImageScrollView alloc] init] autorelease];
[self configurePage:page forIndex:i];
[pagingScrollView addSubview:page];
}
}
How do I re-define the size of the frame? What function should I call etc. How do I centre the image?
I'm new to this so I apologise for the ambiguity of my question.
Cheers
I've figured it out. It was the Frame of the individual pages that I needed to change, so (with the help gained from another question) I wrote a re-orient method.
The first step to this came because I figured out that I needed to iterate through and re-size each frame for each of my pages and then re-apply the frames to the view. For this to happen I needed to create an array which I would fill in the For Loop above. I have 7 total pages.
Then I could (on rotate) call the below re-orient method to re-size each view:
- (void) reOrient{
if(UIInterfaceOrientationIsPortrait(self.interfaceOrientation)){
CGRect f;
int i = 0;
for (ImageScrollView *page in pageArray) {
f = page.frame;
f.size.width = 320;
f.origin.x = (f.size.width * i);
page.frame = f;
pagingScrollView.contentSize = CGSizeMake(f.size.width * 7, 480);
i++;
}
}else{
CGRect f;
int i = 0;
for (ImageScrollView *page in pageArray) {
f = page.frame;
f.size.width = 480;
f.origin.x = (f.size.width * i);
page.frame = f;
pagingScrollView.contentSize = CGSizeMake(f.size.width * 7, 480);
i++;
}
}
}
This worked for me:
- (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation duration:(NSTimeInterval)duration
{
[super willRotateToInterfaceOrientation:toInterfaceOrientation duration:duration];
//get current page based on offset before rotation
NSInteger currentPage = self.scrollView.contentOffset.x / self.scrollView.bounds.size.width;
//set anticipated scrollview content size by switching width and height (they will be switched after rotation)
[self.scrollView setContentSize:CGSizeMake(totalPages * self.view.bounds.size.height, self.view.bounds.size.width)];
//set the anticipated content offset based on height before rotation
[self.scrollView setContentOffset:CGPointMake(currentPage * self.scrollView.bounds.size.height, 0.0f)];
}
Basically I am setting the content offset for the new scrollview content size before rotating (I'm switching height and width for the anticipated height and width).
This worked for me when rotating a full-screen paged UIScrollView.
All of the paged subviews have the following autoresizing mask so that they neatly fall into place after rotation:
UIViewAutoresizingFlexibleLeftMargin | UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleRightMargin

pagingScrollView Slideshow

I have started trying to understand the way apple implements the photoviewer app for the iPhone after watching both videos from WWDC 2009 and 2010 about scrollViews and paging through photographs and I am taking each step very slowly to understand the processes very well before I implement it all into my app.
I have run into a couple of problems at the moment:
Firstly I have it set up to have a paging scroll view to swipe left and right between photos with a bit of space in between like on the videos but when I add an image inside a UIImageView th image is too big for the screen, I have tried adding UIViewContentModeScaleAspectFit; to no effect.
When I go through the for loop to look at each element of the array containing the images the UIViews overlap and show one photograph on top of the other, I would like to know how to separate them into the next section of the paging scroll view.
- (void)loadView{
UIImage *img0 = [UIImage imageNamed:#"29.png"];
UIImage *img1 = [UIImage imageNamed:#"33.png"];
NSMutableArray *imgArray = [[NSMutableArray alloc] initWithObjects:img0, img2, nil];
CGRect pagingScrollViewFrame = [[UIScreen mainScreen] bounds];
pagingScrollViewFrame.origin.x -= 10;
pagingScrollViewFrame.size.width += 20;
pagingScrollView = [[UIScrollView alloc] initWithFrame:pagingScrollViewFrame];
pagingScrollView.pagingEnabled = YES;
pagingScrollView.backgroundColor = [UIColor blackColor];
pagingScrollView.contentSize = CGSizeMake(pagingScrollViewFrame.size.width * [imgArray count], pagingScrollViewFrame.size.height);
self.view = pagingScrollView;
for (int i=0; i < [imgArray count]; i++) {
UIImageView *page = [[UIImageView alloc] initWithImage: [imgArray objectAtIndex:i]];
page.contentMode = UIViewContentModeScaleAspectFit;
[pagingScrollView addSubview:page];
}}
As I have mentioned I am fairly new to programming for the iPhone and am taking things slowly to fully understand, eventually this program will mimic the native app with pinching and tapping for zoom.
If you're using UIImageViews, you should make sure that your view has its clipsToBounds field set to yes. Try adding:
UIImageView *page = [[UIImageView alloc]
initWithImage:[imgArray objectAtIndex:i]];
[page setContentMode:UIViewContentModeScaleAspectFit];
[page setClipsToBounds:YES];
[pagingScrollView addSubview:page];
Then, make sure you are setting your image's frame to the correct offset within the scroll view. The frame's origin.x needs to be the width of the frame times the image index. So you need something like this:
[page setFrame:CGRectMake(i*pagingScrollViewFrame.size.width, y, width, height)];
where i is your index from your for loop.
Though in the sample code from the WWDC session you're referring to, this is done in a method called -configurePage. Have you downloaded the sample code?
-[UIImageView initWithImage:] sets the frame to be the image's size. You'll need to use page.frame = [[UIScreen mainScreen] bounds] or similar to scale images to the correct size.

iPhone UIScrollView - how to get an image title

I'm ATTEMPTING to learn UIScrollview using Apple's Docs and their sample code http://developer.apple.com/iphone/library/samplecode/Scrolling/index.html but something SO simple is escaping me.
How do you tell what image is currently on the screen, so that if I selected one of the images in the horizontal scrolling view, how would I get the filename of the image, or even a pointer in the array, to then do something further with the image?
I thought with Page Control enable I might be able to find a page # and map it to the image. I thought about counting deceleration to count pages, but a flick no full enough will increment it and give a false number.
The last thing I could think of is to get contentOffSet and divide by image size which will give a 1, 2, 3 and I could point to the array (too tired to try tonight... thought I might ask before I waste a lot more time ;-) ).
Any other ideas? I thought there would be a method somewhere that they use in the photo album app.
PS: Here's the code:
- (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;
// 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:#"Card %d.png", 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];
[imageView release];
}
[self layoutScrollImages]; // now place the photos in serial layout within the scrollview
This was easy after a good sleep!
CGPoint p = scrollView1.contentOffset;
NSLog(#"x = %f, y = %f", p.x, p.y);
Now just divide by 320 (if horizontal and full screen image) and add 1 (because it starts at 0).
Hope this helps someone else!
Paul

UIImageView change Width and Height

I've read various posts on here asking similar questions... I've tried various ways that were posted including bounds and frames etc. including the following:
myImage.frame = CGRectMake(0.0f, 0.0f,50.0f, 50.0f);
and:
myImage.bounds = CGRectMake(0.0f, 0.0f,50.0f, 120.0f);
neither of those work.
However, I find it interesting that the following code let's me move the Image around but doesn't change the width:
CGRect frameRect = myImage.frame;
frameRect.size.width = 50.0f;
frameRect.origin.x += 10.5f;
myImage.frame = frameRect;
So why don't any of these change the width/height of my ImageView?
I found another post on here that basically states I have to right a small book of code to get it resize my image... is that true?
Such as this one:
UIImage: Resize, then Crop
certainly this is simpler than that??
The following will change the size of the UIImaveView, clipping the underlying image without resizing it and keeping it aligned to bottom left of view:
imageView.frame = CGRectMake(
imageView.frame.origin.x,
imageView.frame.origin.y, newWidth, newHeight);
imageView.contentMode = UIViewContentModeBottomLeft; // This determines position of image
imageView.clipsToBounds = YES;
First off, you can't set the frame or bounds of the UIImage - that will only work on a UIImageView.
I've found that changing the frame of a UIImageView causes the Image to be scaled to the new size. Sometimes, that's undesirable - and you want instead to crop the image.
I can't tell if this is what you're asking for, but here's some code to crop an image to a specific size in a UIImageView:
UIImage *myImage = [UIImage imageNamed:#"photo.png"];
CGRect cropRect = CGRectMake(0.0, 0.0, 320.0, 44.0));
CGImageRef croppedImage = CGImageCreateWithImageInRect([myImage CGImage], cropRect);
UIImageView *myImageView = [[UIImageView alloc] initWithFrame:cropRect];
[myImageView setImage:[UIImage imageWithCGImage:croppedImage]];
CGImageRelease(croppedImage);
From what I get of the question, the OP wanted to change the size of the UIImageView when the size of the container UIView is changed. The code below will do it...
UIView * foo = [[[UIView alloc] initWithFrame:CGRectMake(0, 0, 25, 25)] autorelease];
foo.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
UIImageView * bar = [[UIImageView alloc] initWithImage:
[UIImage imageNamed:#"test.png"]];
bar.autoresizingMask = foo.autoresizingMask;
[foo addSubview:bar];
[self.view addSubview:foo];
The key here are the foo.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight and the bar.autoresizingMask = foo.autoresizingMask; lines. Forget either of these, and the whole jigmarole will stop working.
Well, if your read the documentation about UIIMage you can notice that is impossible to change any parameter of an UIImage after create it, the solution I've implemented for use high quality images for change some parameter of (for example) the SliderControl as Screw Image, is the next one:
UIImage *tumbImage= [UIImage imageNamed:#"screw.png"];
UIImage *screw = [UIImage imageWithData:UIImagePNGRepresentation(tumbImage) scale:2];
With that, I can to use 100x100 px image in my apps scaled to 50%.
Kind regards.
Try Using a UIScrollView. Add the UIImageView to the UIScrollView in Interface Builder you can then control the position and size of the image as follows:
CGRect rect = [scrollView frame];
rect.origin.x = 50.0f;
rect.origin.y = 0.0f;
rect.size.width = 320.0f;
rect.size.height = 150.0f;
[scrollView setFrame:rect];
If you tried those methods cannot work, the only way to do it is to add the constraint of width and height to the UIImageView.
// Create the constraint in code
NSLayoutConstraint *constraint0 = [NSLayoutConstraint constraintWithItem: myImage attribute:NSLayoutAttributeWidth relatedBy:NSLayoutRelationEqual toItem:nil attribute:NSLayoutAttributeWidth multiplier:1.0f constant: yourNewsWidth];
NSLayoutConstraint *constraint1 = [NSLayoutConstraint constraintWithItem: myImage attribute:NSLayoutAttributeHeight relatedBy:NSLayoutRelationEqual toItem:nil attribute:NSLayoutAttributeHeight multiplier:1.0f constant: yourNewsHeight];
[myImage addConstraint:constraint0];
[myImage addConstraint:constraint1];
Use myImageView.frame = myNewPosAndSize; to resize or reposition your image view (as with any other view). It might confuse you that the image view draws its image with its original size, possibly exceeding its own dimensions. To disable this use myImageView.clipsToBounds = NO;
You don't have to write a whole book, you can copy that code.
I believe the UIImageView always draws the image at 0,0 at a 1.0 scale. You'll need to resize the image if you want to continue using the UIImageView.