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Passing data between Fragments of a viewPager that contains recyclerViews

I don't know how to pass data between my fragments "books" and "reservedBooks" in a viewPager which is an object of my class "bookCard" and part of my recyclerView to add it to the other recyclerView in my fragment "reservedBooks" throught the click of a button "reserve" that is part of each member of the recyclerView

You need a static place for storing data for any type of your data(books and reversedbook) you can use static array or database android
Then every time that you select an item , this item must remove from books in that staic array and add to another static array for reversedbook,
And every time that you replace fragment in view pager, you must update recyclerview by notifydatachanged()

can i delete array of listView but not update listview?

I spent some time to google it, but didn't help.
I have a listview that contains an ArrayList.
Can I collect all data in array, show it in listView and delete array, but not update listView - so data will be on screen?

Yes until you scroll the list view to next visible item (or call notify item set change), then ListView ask adapter to provide object for example at 5th position and you will get ArrayIndexOutOfBoundsException or NullPointerException. So if you want to avoid that you have to copy your list elements to another ArrayList instance and pass it to your adapter.

arrayListMain.get(position).remove(arrayListChild.get(position));
notifydatasetchange();
arrayListMain is which arraylist your are use at setAdapter and arraylistChild is arrayList in your adapter

Add Search suggestion to the header of recyclerview

I have an Recyclerview adapter class and searchbox as a header of recyclerview.
Everything is working fine.Now i want to get search suggestion while i type first few letters of items of Recyclerview. Using AutoCompletetextView we needs to pass adapter of Recyclerview:
setAdapter(adapter) but my problem is how should i pass adapter as i am in adapter class.

use after arraylist or dataset values changed
adapter.notifyDataSetChanged();

NavigationDrawer update items

I'm using the navigation drawer example in Android. What's the easiest way to change the string items in the adapter dynamically? Do I just create a new adapter and set it with my new values?
The problem is I'm altering the string items based on user state logged in and logged out. How do I access it from a non static context and just say update list adapter? It doesn't seem to be re-drawing itself and running my adapter code which is dynamic based on user state, so I guess it runs/inits once and I have to create and load a new adapter if I want to change it later?
Thanks.

You haven't given us much to go on (a little code would be nice), but you can update the data in the ListView by calling notifyDatasetChanged() on the Adapter. If you are not using a custom Adapter e.g. an ArrayAdapter then you can just create a new Adapter instance with different String values and set it to the ListView.

Invisible listview item row

i want to implement a search Text to listView,
i load the listView items from server.
Currently, everytime that user enters something to the searchText i remove all items in the listView and add them again to the listView (if they contain the user entered string)
However it takes alot of time, to remove the whole listView and then start reload all items to list again
Therefore i want to loop all over the listView and to invisible the un-matched rows, is it possible? (something like View.GONE)
for example, i want to invisible the k-th item row in listView.
Also, i will want to change this item row to visible again.
thanks alot

you don't need make the view invisible. Have a EdiText at the top. Then have filter for your listview and display items in listview accordingly. call notifydatasetchanged method to refresh listview.
An example of search on listview.
http://www.androidhive.info/2012/09/android-adding-search-functionality-to-listview/
An example of listview with custom filter can be found in the link below
Search in ListView with EditText