What is the correct way to show/hide a UIScrollView? - iphone

I have an iPhone application that uses a UIScrollView to display a larger version of an image on the main screen. I am using IB to create the main screen that has text, small images, and price about a product. I have it setup to show/hide the UIScrollView if the user touches the small images. It works ok, but things are pretty messing in the IB layout. I have to put the UIScrollView over top of everything else and make it hidden by default. What I'd like to know is if there is a better way to accomplish this. Can I create a new nib and load the scroll view in it and load that nib when the users touches the small image? Should I construct the scroll view in my code and not use IB? Any input is appreciated!
Sorry if this is a newb question. I'm still learning.

Set scrollView.hidden = YES and then when tapped, set it to NO.

Related

Whats the approach to create a view similar to the one at apple app store

I wanted to know how can we design the view controller such that.., the upper half of the screen remains fixed and the below part of the screen can be navigated through.. !!
Should we use slipScreenController here ?
Your description sounds nothing like the Appstore app but the Appstore app simply has one vertical UIScrollView and another horizontal UIScrollView inside that for images.
If you are referring to browsing categories in AppStore then:
That is a tableView implemented in such way that it doesn't take the whole screen area. You need to create a UIViewController (not UITableViewController) and than add a tableView to the view (using Interface Builder or code). That way you can change the size and position of the tableView and use the remaining area of the view for something else, for example a UISegmentedControl above the tableView.
If you are reffering to reading description and images of single app then I think that UIScrollView is used for displaying images, not sure about the rest.

Special UIScrollView with multiple objects (3) on each page

What I want to accomplish is something like this:
Two different scrollViews, and each one scrolls horizontically. Each showing 3 images, and a half one (or 1/3th) piece of the next image in the datasource of the scrollview.
Does anyone know how to accomplish such a scrollview?
I also want to be able to tap an image to flip it and show some information and a button to the detail. (See lower scrollview).
Tapping it again would just show back the image, much like the coverflow ui inside itunes, but without the coverflow being 3D...
Any help is welcome :)
Thanks in advance,
Lewion
Scroll view doesn't have a datasource. What you are looking for is standard scrolling and nothing special.. So it is definitely doable... Check the scrolling and photo scroller sample codes from apple developer samples. For more implementations of scroll view check the scroll view suite sample code and read the scroll view programming guide.
The flip animation is also a standard animation for a view and is easily doable. For example, create a utility application for iphone. It has a flip side view. See how that animation is done.

iPhone UIImage overlapping text

I have a view with a UIScrollView, UIImageView for a background, and a UITextView. I have created several other views just like this and they all come out okay - with a background image and scrollable text but for some reason, now I can't make that work. Either my image overlaps all of the text so that I can't read it or the UITextView default background (white) shows up so that the user can't see the background image. What could be causing this problem?
Do you use Interface Builder or build the views hierarchy in code?
In both cases you should make sure that the order of your views is correct.
In IB the view that you want to appear on top of all the rest has to be under the rest of the views.
In code, make sure that the text view is the last to be added to the hierarchy.
You could also use the next code in order to check if this is the problem:
[self.view bringSubviewToFront:textView];
Okay, it must have had something to do with choosing the delegate. I can't say that I completely understand how I fixed it but it had to do with declaring the delegate in IB.

UIButton Game character selection to UIImageView animation

I am almost at the end of coding my kids educational application, woohoo!.
But... Im stuck on something.
When app loads i have my main view. It has 4 buttons for flipviews(each with ten views of content) and 4 buttons for character selection(an image that will follow you through every screen of content).
Problem is im unsure on how to link UIButton selection to UIImage display in multiple views. I want the user to choose a character button and then continue to the flipviews and in the views the image displayed should be the one that they have selected on the main view. So everytime they return to the main view they can change the character that will follow them around the app.
Any thoughts, help or code would be much appreciated!
Thank You
Alex
Make a new object, a subclass of UIImageView, which has a -setImage method. Once you set the image, then where ever you embed that object, it will display the same image. You could even have that subclass view have a score displayed next to it, or a name or other stats, so as you go from one screen to another, you have all that info follow you around with the image. No need to create labels in all the screens for global info like that.
In summary:
make a new subclass of UIView or UIImageView in Xcode using the New File... menu. You would do new UIView if you will have other items than just an image.
add methods that allow you to set the image, update text stats etc.
BONUS: you can make the class handle taps, so if a user taps the image, you could do something like provide help or run a cute little animation
embed that object in any screens you wish. Keep in mind that you can have that view be sized differently in each screen using transforms. Cool, no?
that's pretty much it!
Good luck!

UIScrollView vs. UITableView

For a vertical scroller are there any advantages to using UIScrollView over UITableView?
I ask because I am currently using two vertical UIScrollViews with UIImageViews inside of them and am having memory issues and poor scrolling performance. I am not doing much with the scrollers, only highlighting images as they scroll into the center of the scrollviews and adding a delete button above an image if the user wants to remove it. I've started to look at lazy image loading/reuse and it seems that most of these issues have already been resolved in the UITableView class, so I'm wondering if there's any reason to stick with UIScrollView?
You should be able to use a UIScrolLView with no problem if you just, like you said, lazy load the controllers, when scrolling (assuming your views are full size) you dont need to have more than 3 views loaded at any one time, all you need is the current view, the view that goes behind it and infront of it, as you scroll your view you can unload and load the appropriate views. You should look into Page Control sample application, it does exactly this and you can pretty much get all the lazy loading code from there. Link is here https://developer.apple.com/iphone/library/samplecode/PageControl/index.html