Vertical Scrolling for iPhone in ActionScript 3 - ios

I am working on a project for iPhone (flash builder 4.6), in which I have to implement a custom scroll component.
Basically I have to show the Facebook users in a list render-er, scrolling is working fine initially but when the number of friends increases (more than 300) the scrolling freezes (mainly tapping not working, swipe is still working, I mean to say that MOUSE_MOVE event is not working properly here).
If any one have any idea about it, please share with me.

You need to create (or use an existing) list component that uses a virtual list. i.e. only creates enough cells (or renderers) needed to fill a screen. It then recycles the renderers as you scroll.
Have a look at this:
http://madskool.wordpress.com/2011/06/30/tutorial-3-lists-and-pickers/
Or if you are using stage 3D, http://feathersui.com/examples/components-explorer/

Related

GUI areas restricted by the iOS

I would like to be able to use the areas that are occupied by the iOS in my app, using javaFX and Gluon. How can this be done?
That means any javaFX controllers functions as expected. Now they are almost impossible for a user to focus. When I have another controller in the middle area of the screen that one works like normal.
On iPhone 6 you can press the top most area and drag down to get access to a menu. The same exact thing with the bottom-most area by pressing then dragging upwards. And I believe that OS related functionality to be the reason.
The touch event probably do not reach the app properly over these areas. I am seeking to be able to have controllers placed here and have them work just as they are in other places.
This was done by adding a VBox layout, with TextField and TextArea to Gluon Layer - and then adding it to Layers of a class extending Gluon View (Called "BasicView").

quartz core generating loads of VM: UILabel(CA Layer)

I have an app which drags messages dynamically from server, as scrolling to top, old messages will be retrieved and display on the screen like other messaging apps, but my app keeps generating UIlabel, even though no more old messages presents after all the old messages are retrieved, the UIlabel will still be generated if the list is being scrolled, and the source is from QuartzCore, responsible caller is CA::Render::Shemem::new_shmem(unsigned long).
Can anyone help me, I'm quite new at developing ios, and im using objective-C, the memory issue cause my app crashed on every version of iphones as the UILabel stacks and seems like it will never release unless I switched to other chatrooms. Thanks for any help!!
It sounds like you are adding labels to a scroll view. Change your app to use a table view or a collection view to display messages. These classes automatically remove and reuse cells that are scrolled off the screen.

ScrollView rendering takes a lot of time on iOS using Appcelerator

One of our Appcelerator apps is experiencing rendering delays on IOS platform for the screens where there are multiple widgets (customised textfields to meet client UI requirement) being displayed inside the scrollview.
The screens are making use of ScrollView where these custom controls (Widgets) are displayed inside the views. We are seeing the delay in the following scenarios:
When the screen is having quite a few controls displayed (around 10-15 controls).
It is observed that the rendering time it takes and any changes to this control properties while the page is loading (such as setting some properties by calling the methods on the widget) is resulting in extra 2-3 secs delay.
When these controls are dynamically added into the page - say in response to the question by the user we display additional controls to capture the information.
We have seen a clear lag in this case which is not good from the user experience perspective.
Note:
All of these issues are only on IOS platform whereas the same code works pretty good (without any lag) on Android platform.
Tried out using the tableview in place of scrollview but the result is no different.
Using tableview also results in poor scrolling performance.
As some complex views are created and added dynamically, using listView would be challenging.
Can anyone let me know if any of you are aware of such issue and how it was resolved (in any appcelerator project)? Is there any way on the native front setting some property/native code through a module that would help speed up the rendering on IOS?
We are only developing for iPads and iPad Minis using iOS 7.1.1+ using Titanium SDK version 5.1.2 (We have tried latest SDKs, but they haven't solved our problem).

UICollectionView paging breaks after 2^24 pixels

The setup
I have a UICollectionView that allows the user to page through pictures, 12 to a page. There are upwards of 200,000 pictures that should all be available in the app. I'm not expecting a user to scroll to page 20,000, so there's function to jump to a certain page.
The problem
In landscape orientation, paging breaks down on page 16,385. The collection no longer adjusts to the page boundary. If you go back before page 16,384, you can get it to start working again, but no page past 16,385 works.
My delegate also stops getting scrollViewDidEndDecelerating: the message when the bug shows up.
The hypothesis
Page 16,385 in landscape orientation happens to start at pixel 16,777,216 which happens to be 2^24. I think that there's something in UICollectionView or UIScrollView that breaks past 2^24.
Is this just an undocumented limit? Am I out of luck?
The example
I've uploaded a project that demonstrates the problem. Here's the relevant view controller. If you shake your iPad or the simulator, you'll be taken to page 16,384, one page before the bug shows up.
The snark
If you don't think a user should need to be able to go to page 20,000, that's cool. I don't think it's relevant to the question.
I'd say this is an undocumented limitation and would file a Radar bug report, attaching the sample project as evidence. If you are looking for an alternative method, you could try using a UIPageViewController with a collection view for each page. You can choose the swiping animation, rather than the default iBooks-esque animation, and replicate your sample project very closely.
You could just load say 10,000 pages and when the user jumps, load an appropriately different 10,000 pages.
I wonder whether you've tried using multiple sections? Is the limitation per section or for the entire CV?

Why is two finger scrolling behaving differently on two separate ipads?

We're currently working on an iPad version of our web application at work. We are seeing inconsistent behavior with regards to two-finger scrolling on scrollable areas within others scrollable areas across two iPads. Both devices are iPad2 models.
On one device, dojo grids and trees require one finger to scroll. On the other, they require two fingers to scroll. On both devices Safari is being used to view the website.
What could cause this behavior? Is there some setting we haven't discovered that dictates whether you need to use 1 or 2 fingers?
Looks like it's a difference in IOS versions (one is on 4, the other on 5).
It's important to note that
-webkit-overflow-scrolling:touch is not the same as one-finger scrolling enabled by iOS5.
-webkit-overflow-scrolling uses the iPad's built in functionality (the touch acceleration and bounce). However, if the contents in your div change, or you manually move the contents inside the div (ie you made your own div scrollbar and are scrolling the contents), enabling this will mess things up. What it will do is make the "top" of the scroll able div wherever it happens to be located. What does this mean? If your contents are scrolled half way down and then you add new content to the div, with -webkit-overflow-scrolling:touch, the very top of the touch-scroll area will be half way down your div. You will not be able touch-scroll back to the top.

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