How to make ListView loop? - android

I have created listView with about 20 items.
While navigating through keyboard when it's on last and when user hits down button I'd like it to go to first item.
Just like keyNavigationWraps : bool in QML.

You should not iterate the list views, instead you should keep all that data (price/quantity) in a list and iterate over that if you really need to do that. That list can be used to populate the ListView as well.

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Android ExpandableListView save input in each item's edit text on button click

I'm new to Android and can't quite figure out the right approach for the problem I'm trying to solve. I have an ExpandableListView with several items. Each item has an EditText, except the last item has a button. The contents of the EditTexts are to be loaded from the database. When the button is clicked or when the activity is navigated away from, I want to save the contents of each EditText to my database.
I'm not sure what to call from the activity's class, what to call from my adapter, and how exactly to access each item appropriately. Code is welcome but not necessary, I'm just looking for guidance on the general approach. Thanks.
I'd recommend putting a method in your adapter called saveAllValues. It iterates through the list of objects in the adapter and saves them to the database. Call this when your button is clicked and in your activity's onStop() method (which is called when the activity is no longer visible).
You should have your activity fetch the values for the item IDs in an AsyncTask in its onCreate method. Then pass the list of id/value pairs to the adapter in its constructor. It should maintain this list so it can go back through it and save the IDs and values to the DB.
Hope my answers in these links help:
Values of counter changes after scrolling ExpendableListView shows how to maintain the list inside the adapter and how to get list from the activity.
Remove the divider view in the expandablelistview last item shows how to make the last child different from the others.

android - Is there a way to cache a View?

I have a complex listview. Every item in this listview has three EditTexts and two Checkboxes. Outside the listview is a Button for adding rows to the listview, one for continue and one to go back.
Continue and Back does both call something like:
setContentView(R.layout.stepX);
The problem:
If you press continue and then go back all items from the listview are empty. Is there a easy way to save the input or hold him in ram?
My current workaround is to create a Class for a listitem and if you continue every itemdata is read and saved to an arraylist. If you go back it read the arraylist and rebuild the listitems.

Android: How to dynamically replace a list view with another list view like Instagram with onClick?

I'm building an android app and I'm trying to replace a list view with another list view if you click a button, like the notifications page on Instagram. On that page, if you click on the top "following" button it will show you a listview of what your followers have liked. If you click on the "you" button it will show you a listview of what people have liked your photos.
Any help would be greatly appreciated!
You can do it by following ways,
1. add Two listviews and can change the visibility as per your requirement.
2. On button click you can load the other data into same list view and can update your adapter in the same list view.
in 1 you have to load two list view at first which will consume more time if data is larger sure you can write a login in asynctask to load list views in background thread.
in 2 you have to update your adapter at the button so you will have to provide some progress bar of dialog for user while you list view is getting update.
You can use either of this whichever suites you best.
Simply , You don't need to switch Listview , you only need to switch adapters .
eg, you can switch to mFollowingAdapter when clicked on Following button and switch to mYouAdapter when you select "You" tab. that's it.
You should write a list, that has a custom adapter. This adapter will be able to display BOTH views you want to display.
If the data to be displayed is the same format (ie. both have an imageview next to a textview), you are in good shape.
When you want to switch to a different list, get the information you would like to display, replace the data in your the collection backing your list, then notify the list that the data has changed, and it should redraw.
So, this might look like:
create ArrayList() with data A
setup List, with this data and display
replace the ArrayList() with data B
call listView.notifyDataSetChanged
You can still do this if the Data A, and Data B have different views, in this case, you would need to handle this logic in your custom adapter.

Mark all the previously selected items from a ListView in an other Color when returning from activity

I am using a ListView in combination with a HashList to show data from an SQL Database through JSON. Everything works fine. But now I want to have a special feature.
In the ListView are round about 400 Items. So if i click one of the item to view its content and switch via Backbutton back to the Listview, i want to have the viewed Item from the Listview being marked in another color so that the user sees directly which oh the items he already has clicked.
I painted an little grafik for you, for better understanding
On the left side, the original View. After i View the 1st,5th and 8th Item of the list, the list should look like at the right side.
Is this possible?
You can implement your own adapter, then have an boolean array to store the current status of every row, and in the getView function assign a different color to the background of the selected rows based on your boolean array.
For this you will need also to set an onClick event in your rows to open the previsualization view and there also check the boolean array as "visited".
For more info about how to make custom efficient adapters, please read this
To simply let the user choice more than one row you can use
listView.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
in your list

List focus on a particular item in that list dynamically

In my project i have a ListView for handling the list of a product. In that i have a list of 100 Items in that List view. Each and Every time i have been seeing the first row of the ListView..
If i need to see the data in the ListView Means, i need to scroll down, Can i focus directly to a particular item by any function by passing the position(ID) of the ListView..
For Example this is my ListView that contains 11 items in it..
I'm seeing every time the ListView as the following,..
And my try is, If i give the ListView position as ID=5 means, can i get the Focus of the ListView as follow, in the opening itself...
Can we get this by ListFragment method or anything else?
Suggest me for the Best..
try this, use setselection
listview.setSelection(position);
Don't know about ListFragment but in listview, you can use listview.setSelection(position);
This method will help you to achieve this
for example: listview.setSelection(5);

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