I need a simple way of scrolling through photos and zooming each photo as needed. Just like original Apple's Photo app. I understand the concept: UIScrollView has many UIScrollView subviews as pages and each of those has a UIImageView to zoom in.
However, I've also seen an example, which I can no longer find, with more efficient way of doing this - using only 3 pages (UIScrollView's) for as many photos as there are to save memory usage. So basically, if there are 10 photos, only 3 pages shown (centered visible, left hidden, right hidden) and as you scroll left or right new images are being placed into those pages to simulate an effect of continuous scroll.
My question is how is this done or is there an existing example so I do not reinvent the wheel?
You might wanna take a look at MWPhotoBrowser, it's pretty the same as the Photo app.
https://github.com/mwaterfall/MWPhotoBrowser
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I have a problem. I want for each record in my core data database to draw an UIImage view on screen. But the problem is that I want to make a sort of grid. On the link below you see what I want to achieve.
picture
So my question is, how do I draw an image on screen in code. And place those images in a sort of a grid. using a collection view is no option, because the app should be running on all IOS devices.
While you could implement a custom UIView and implement the drawRect: method and draw UIImages there, I suggest just using multiple UIImageViews as subviews on your "main" view. Your view might be embedded in a UIScrollView, or you could use a UITableView with custom UITableViewCells. Whichever is easier is probably related to how you can interact with the view.
Building that one huge image view is something that I'd definitely try to avoid - it costs many many (probably unnecessary) memory, and it might be slow as well. Definitely not very flexible to handle, and a pain to update dynamically.
A quick cheat for something like this is to use a Table View and then in each cell to place another TableView but rotated at 90 degrees.
You can then use this second TableView to display the pictures etc...
This will give you a table that scrolls up and down and then each cell can scroll left to right.
I'd suggest subclassing UITableViewCell and setting it up as a UITableViewDelegate and UITableViewDatasource.
You will also have to remember to rotate the content of these "sub"tables by 90 degrees also so that they are the right way up.
This sounds like a lot of work but if you push the management of the sub Tables into the cells then it actually becomes quite easy.
I need to create a scrollable composite view on iOS. That is to say, the view will contain at least one image, possibly a button, and some text (that we may wish to format with bold fonts, etc). The amount of data, and particularly the amount of text, is variable, from maybe 4 lines to maybe 100. The data is "variable" to a degree, and in particular the image and text do not come joined at the hip.
This all needs to fit in a "pane" of about 280h x 115w pixels in a portrait-only layout.
A single UITextView doesn't provide the facilities to display an image or format the text.
A UIWebView provides the ability to display the image and formatted text, but the button is a problem (not even sure if it's doable).
A UIScrollView would easily allow the image and button, and then a UIWebView could be embedded in the scroll view for the text, but then scrolling becomes a problem -- I'd like the entire view to scroll as one, without having to resize the web view to contain it's content, and without the confusion of a scrollable within a scrollable (the doc warns of "unexpected behavior").
(I'm guessing your thoughts at this point are that I want too much.)
So, any suggestions? What's the best way to get close to what I need here?
In iOS5 the UIWebView has a scrollView property, which is a normal UIScrollView. You should be able to add a UIButton as a subview of the scrollView to achieve what you want, although positioning it correctly may be a challenge. Prior to iOS5 you could cycle through the subviews of the UIWebView to find the UIScrollView with isKindOfClass...
I suggest testing with a UIWebView inside your UIScrollView. I don't see any interference in the iOS 5.0 simulator. I don't know if there are problems in iOS 4.0.
If you find that there is interference, you can prevent it by setting the web view's userInteractionEnabled property to NO, either in the nib or in code. This will prevent the web view from receiving any touches, so the user also won't be able to pinch-zoom it, follow links in it, or copy text from it.
In the web view's delegate, implement webViewDidFinishLoad: to set the web view's size and the scroll view's contentSize. For example:
- (void)webViewDidFinishLoad:(UIWebView *)webView {
CGRect frame = self.webView.frame;
frame.size = [self.webView sizeThatFits:CGSizeMake(frame.size.width, HUGE_VALF)];
self.webView.frame = frame;
self.scrollView.contentSize = CGSizeMake(CGRectGetMaxX(frame), CGRectGetMaxY(frame));
}
When I did a similar thing, I had a dozen of views which I added to the UIScrollView and then calculated the frames of all the views. Granted, it was an extremely tedious work, given that some views could get hidden under various conditions. The layout code was actually pretty simple, laying out views from top to bottom, but ugly. The upshot is that it works like a charm, fast and reliably. You can even trivially wrap it in an animation block.
I'm building a iOS app which involves lots of photos displayed as rectangular areas on the screen. You can click on that area and see a bigger version of the photo. Kind of like those wallpaper apps, where you first see a grid layout of small wallpapers and then you can go in to see a bigger version.
So, I'm wonder what's the pros/cons in terms of memory usage and scalability between setting them up as UIButton (w/ background) and UIImageView?
I'd use an UIButton. It's easier to use as a user because it's made for touching them. Since UIImageView directly inherits from UIView it doesn't really know targets and selectors. So you'd have to implement this using touchesBegan:withEvent:. UIImageView is more efficient at drawing pictures though. UIButton already knows that so you'd only have to set the picture.
I got trouble to add slideshow to my application.
Currently, I have a UIView composed of a segmentedControl.
I made two "views" that I hide or display depending on the selected button.
I'm looking to make a simple slideshow in one of my two views. I made a UIImageView because it is simple to display pictures.
So I'd like to display my pictures one by one and it is possible to move from one image to another by sliding your finger to the right or left (just as in the native app "Photos").
I tried to adapt example codes from the documentation, but without succes.
So I'ml looking for help.
Thanks,
jb crestot
SO, I've actually done this and it's fairly easy. The ingredient that you are missing is a UISCrollView. My implementation did exactly what you describe (allow the user to go back and forth between a set of images).
Basically, add a UIScrollView to your View in interface builder and you will be creating the UIImage views with code (a simple for loop) and setting their images the same way. I did this safely with no memories issues with about 15 images (PNG's). There could be a potential performance issue with this message if you are working with a large number of images (say 40?)
I hope this helps, let me know if you need a code sample to see how this works.
You may consider using a custom class, such as iCarousel, linked below. Each of these views could be your image, and then tapping on them could launch a fullscreen view for example.
Keep us posted!
http://cocoacontrols.com/platforms/ios/controls/icarousel
See apple's page control sample application.
Does someone have an "easy way" to make a view like camera roll app? I need to display miniature photos (buttons) and push new views from them. I don't know how to display miniature images in a scroll view. The number of miniatures is large, so they don't fit the screen, and I think UIScrollView is the only solution.
Check out TTThumbsViewController, part of Three20; this should pretty much do what you want (and it's open source if you need to change it).
A scroll view really just controls the visible region of a single content view. If you want a grid of small images, you'll need to create a view that contains a number of image views or otherwise displays the grid of images. Make this the content view of the scroll view. Also, it'd be a good idea to construct your image grid view such that it only loads and draws the images that are visible, particularly if you're going to display a large number of such images.