Android ListView alpha scroller for quickly scrolling long list - android

The Contacts app shows a button on the side of the screen that acts as a little thumb to allow you to quickly scroll the big list. I have a very long list that would benefit from this navigation behavior, but can't find any documentation as to how to enable it.
Is it a behavior that's built into the SDK, or must I write it myself?

Yes, it is included in the sdk. See here:
http://developer.android.com/reference/android/widget/AbsListView.html#attr_android:fastScrollEnabled
just set this property. If you want to further enhance this like the contacts that shows the letters for the section you are in you can use this.
http://developer.android.com/reference/android/widget/SectionIndexer.html

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Nativescript Vertical Screen Slide / ViewPager

What is the easiest way to implement a screen slide in Nativescript like shown in Android Viewpager , but in a vertical direction ? Another example of this functionality would be the rss reader feedly where you can change rss feeds by swiping up/down.
The page should allow vertical scrolling to the top/bottom and then transition after a certain treshold.
I already encountered nativescript-slides, which can only do horizontally sliding.
So is there a "nativescript" way or do i have to implement it as native android/ios feature (for example by this) ? In either case a sample on how to integrate it in nativescript would be great.
Update
Recorded an example:
taken from this Repo with Android native code. The outstanding PR made changes to offer vertical scrolling in the list. But the repo seems to be outdated and a bit buggy.
I can provide more info later but there's a new plugin implementing the native controls for android and iOS for slides/carousel her https://github.com/alexrainman/nativescript-carousel-view and vertical swiping is on his radar, I think he might even be close to completing that.
To give an answer for anybody interested in above nested scrolling animation:
For Android I had to implement the native ReyclerView in Nativescript in favor of the NS buildin ListView. It is an optimized view structure which among other things allows nested (vertical) scrolling and can be used as replacement for an ordinary list.
Together with https://github.com/alexrainman/nativescript-carousel-view works like a charm!
Anyone that ends up here still looking for ways to achieve this.
I spent a lot of time trying to figure out a way to achieve this and tried to find ready plugins for this. Also tried to use the plugin from Alexrainman but eventually gave up since the plugin was not up to date with the current nativescript-version.
My solution:
I used radListView as a basis for this implementation and leveraged the methods and events on the radListView.
By using scrolled-event I gathered data for the use of the scrolling feature: scroll Speed and scroll direction. (These might be also taken from the event data, but since I did not find the event details from the Nativescript-documentation I gave up trying to guess where to find this data on the event-model).
Then I also saved the fixed height of one item on my list (The height I fixed to screenHeight-200).
With all this info, I managed to hook the event "ScrollDragEnded" and add logic that makes my list behave like a vertical slider. Moving on the list by method "scrollToIndex" and figuring out which index to scroll and when by leveraging all the data mentioned above.
This is the way I managed to make a pretty good vertical slide.
Good luck!

Create UI like Chrome for Android

I want to implement this behaviour [https://github.com/gleue/TGLStackedViewController] in an app that I am trying to make.
The closest thing/the effect that I want to achieve is how the Google Chrome browser behaves.
Tile/card interface
Be able to access a form of navigation (access other tabs) when user pulls down the address bar
Be able to re-arrange the tabs in any order the user wishes
Photo taken from this Android Layout : How to implement a UI similar to deck of cards? SO question
Is there anyone out there who has tried to implement this kind of behavior? Do you guys know any libraries that can help achieve this effect? It would be very helpful! Thank you
systemUI/Recents package, as mentioned by Andrei, can be your starting point. It adds a little more to the flat rendition of chrome tabs.
I have been meaning to refactor systemUI/Recents package ever since I got the L update. I finally got to it.
A sample project is hosted at: Link
Even though the viewgroup recycles, it updates the progress map (child properties) for all children on each scroll step. This will lead to lags with large data sets. For a few hundred, it should be fine.
The sample project uses Picasso for loading and caching images from LoremPixel. Since these are random images & may repeat, you can verify that they are bound correctly by looking at bottom left of the image.
If you feel like looking through the AOSP code, the functionality you are looking for is actually open-source and you can find it in Android 5.0 in the recent apps screen. This is the code you want to look at on github.
The view you want to extract from AOSP is the RecentsView. This would be the best approach.
You could also consider extending StackView and overriding onLayout() so you get the children to lineup.
One other option is to extend ListView, override drawChild or layout methots and try to shift the views according to their position. You can find some inspiration here and here

How to create layout

I'm trying to create an android app which consist of a following list which has capability to expand once a user clicks on particular row.
I have already integrated an ExpandedListView to it. But there is a problem with that.
If i press on a EditText the focus wont stay, it appears there are some common issue on that scenario.
Is there is any layout structure which i can use rather than a expanded list view.
Here is the screenshot of my app
Thanks
Take a loot at here .Its a best alternative library for Expandable listview.And you will have many customization options.

android 4.0 spinner usage

I want to be able to do what is on the picture, provided by this link, under the "Allow cutting through hierarchies" section. I thought that I could do that using a spinner, but from the android documentation I realized that a spinner can show one child at a time and lets the user pick among them. In my case, (and from the example I provided), you have some other text displayed, and then you can choose from some other options provided in sth that looks like a popup, list that contains the things that i want to choose from. I don't know how this is implemented, but it's used in the google music app for android 4.0. If someone has an idea, have implemented sth like this, please give me some advice.
It is not a spinner. Its just a view (in the Mail app a relative layout) See here
On click this View opens a popupmenu.
Therefore it is looking like a spinner but you can add you custom behaviour.

How to implement Android 4.0 like swipe to dismiss functionality in ListView?

I'm working on an app in which I would like to implement swipe-to-dismiss functionality in the ListView - similar to what we see in Android 4.0's notification bar, recent apps list or browser tabs. I want to run the app on the devices running Android 2.2+. See the following image. I also want to change the transparency of the item being swiped-away - just like in ICS.
I checked the source of the ICS web browser on http://grepcode.com/file/repository.grepcode.com/java/ext/com.google.android/android-apps/4.0.1_r1/com/android/browser/TabScrollView.java?av=f but couldn't figure out which class is particularly responsible for implementing this functionality.
Can anyone point me in the right direction here? Can we do this using Android Compatibility Library? Please let me know. Many thanks.
I've thought about implementing such a feature as well, but I haven't done it yet. So the only thing I can provide are some ideas on how I would approach that problem. If I've eventually written some code I will post it here.
The main class needed is a custom Adapter which extends a ListAdapter (ArrayAdapter, SimpleCursorAdapter etc.).
The adapter applies a View.OnTouchListener to all of its Views.
Whenever that listener detects a horizontal scroll dx, it calls concernedView.offsetLeftAndRight(dx) (which will make the view draggable). Of course the adapter has to save the current horizontal offset for the view. If the user was dragging a view and removes his/her finger from the screen, the touchListener will detect this as well and start a slide back animation. Using the current offset we can also calculate an alpha value, so the view will fade out when it approaches the screen borders.
If one list entry is eventually dismissed by the user, it becomes a bit tricky, and I'm still not sure how I would implement the following action: The list content has to be updated (or the adapter has to ignore the dismissed entries) and the views that were below the one that was dismissed must hover upwards in order to fill the gap. I think it might work to let the ListView load the new content, but that would fill the gap instantly. In order to avoid that, I would then start an animation that lets all the concerned views hover from their old position (where we still had the gap) back to their current position (where the gap is filled).
These are just some of my thoughts on the issue that might help some people getting started on working on the problem. Like I said, I'm probably going to implement that sometime in the future and of course I will post the code here.
I would appreciate any feedback in the comments, but I don't want to thorougly explain every single aspect of my idea, that would take me too much time ;)
I know this is quite an old question, but for anyone still searching for this, you can have a look at Roman Nurik's library here: https://github.com/romannurik/Android-SwipeToDismiss
This shows how to create the required behavior for list-view as well as for normal views.

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