Adapters

Adapters

This package contains all necessary (RecyclerView) Adapters and related classes and interfaces like the OnRecyclerItemDownloadButtonClick interface and the RecylcerAdapterSwipeGestures

Used Recycler Views

There are five Recycler Views needed throughout the App:

1. A vertical RecyclerView to display files from the server (RemoteFile). Used in FragmentDownloadCenterAll.

   It shows the Name of the file, its size, date and a download button.

2. A horizontal RecyclerView to display files located on the Server which is used in FragmentDownloadCenterAll and RecyclerAdapterRemoteDirectories It displays the name of the file, its size, date and a download button.

3. A horizontal RecyclerView to display the status of map request made by the user. It shows : the name of the request, the time passed since the request was submitted, the status, and a short description of that the status means. Used in FragmentRequestStatus

4. A recycler view to display directories (on the server). It it displays a formatted name of the directory, and its contents (maps as RemoteFile) using the recycler view described in 2

5. Another recycler view to display the same as the first one, but this time it needs to display files on the local storage (File) Equally to 1. it displays the name, date and size of a

   Additionally it can show a little green dot to show which map the user has chosen. This is invisible by default and can be made visible if needed,

   Also it is possible do delete and/or chose Maps by swiping the recycler item.

Implementation

RecyclerAdapterLocalFiles

The RecyclerAdapterLocalFiles is the adapter for the recycler view described in 5.

It takes a ArrayList<File> which will be created by the LocalMapsRepository and a int resource, which is the layout id of the used item layout. in this case the recycler_item_vertical

It provides a File which is used to search in the recycler view by the name of the item Also it has a setter for a OnItemClick interface which isn't used at the moment.

If you want to use it :

mRecyclerAdapter.setOnItemClickListener(new RecyclerAdapterLocalFiles.OnItemClickListener()
{
    @Override
    public void onItemClick(int position)
    {
			//Your code here
    }
});

As described there should be Swipe gestures to delete and choose a map. This isn't implemented in the adapter itself but in the class RecyclerAdapterSwipeGestures ...later more on that.

RecyclerAdapterRemoteFiles

The RecyclerAdapterRemoteFiles is the adapter for the recycler view describe in 1. and 2

It takes an ArrayList<RemoteFile> which will come from the corresponding Repository. and a int resource. Now as i said there should be a vertical and a horizontal version of this recycler view. That's why in this case 2 layouts can be used The recycler_item_vertical as known from RecyclerAdapterLocalFiles and the recycler_item_horizontal both have the same views with the same IDs, but look slightly different.

Again this Adapter provides a Filter to search items by their names and a OnItemClickListener which -again - isn't used yet but can be implemented like described before.

RecyclerAdatpterRequestStatus

This is the adapter for the recycler view described in 3.

As the requests come as string from the server it takes a ArrayList<String> . The layout resource in this case should be the recycler_item_request_status Again this recycler adapter provides the same functions like the other ones. Namely Filer and OnItemClickListener.

As mentioned this time we get a String ArrayList This means the recycler view needs to process the strings for himself to set the right information to the right view. This happens in onBindViewHolder using a StringTokenizer

**Note : The additional information texts to the status come from the String resources and not from the server **

RecyclerAdapterDirectories

The recycler view described in 4.

In this case its a bit more complicated The recycler view takes a ArrayList<RemoteDirectory> which are the directories it shall display but also a HashMap<String, ArrayList<RemoteFile>> which is a HashMap of the name of the directories and another ArrayList, which contains the files which are in these directories.

With that in mind the recycler view takes the layout recycler_item_directories which -again has a recycler view in it.

So : I use the ArrayList with the RemoteDirectories to set the name in each recycler view item and then fill the recycler view in the single items using the RecyclerAdapterRemoteFiles with the recycler_item_horizontal_layout and the ArrayList which is in the HashMap.

I hope i made it clear ...but its basically a recycler view inside a recycler view item

Note : I think this can be implemented better using just the HashSet but i haven't done it yet because ...it works for now

A few more things

You may have seen the setData methods in some of the Adapters, they are there because the ```mAdapter.notifyDataSetChanged()`` doesn't work with LiveData objects as they are used here.

You also may have noticed that the adapters always have a "backupList" . this is needed to restore the list again after it was filtered. The filter directly alters the list which is displayed but after finishing the search the list should be complete again. That's where the backup comes in.

also I used horizontal recycler views in some cases.

That can be achieved by

LinearLayoutManager recyclerLayoutManager = new LinearLayoutManager(this.getContext());
recyclerLayoutManager.setOrientation(LinearLayoutManager.HORIZONTAL);

mRecyclerView.setLayoutManager(recyclerLayoutManager)

Swipe Gestures

As described in 5. it should be possible to delete or choose a map via swiping on the recycler item. this is achieved using the RecyclerViewSwipeGestures which can be initialized implementing SwipeCallbackLeft, SwipeCallbackRight or both.

The RecyclerAdapterSwipeGestures class does the animation and calls the implemented methods from the interfaces when a left or right swipe was made.

Example:

//For both swipe directions
ItemTouchHelper itemTouchHelper = new ItemTouchHelper(new RecyclerAdapterSwipeGestures(this.swipeCallbackRight, this.swipeCallbackLeft));

// for just the left swipe
ItemTouchHelper itemTouchHelper = new ItemTouchHelper(newSwipeCallbackLeft()
{
    @Override
    public void onLeftSwipe(int position)
    {
			//Your code here
    }
});

// For just the right swipe
ItemTouchHelper itemTouchHelper = new ItemTouchHelper(new SwipeCallbackRight()
{
    @Override
    public void onRightSwipe(int position)
    {
			//Your code here
    }
});

// and then: 

  itemTouchHelper.attachToRecyclerView(mRecyclerView);

Note : I initially intended to make it possible that by just passing one interface the animation for the other swipe direction wouldn't show up that would make it a lot more flexible ..but I didn't got it working. So two options here : either make it work that way, then the SwipeGestures could be used in other places too or unify the interface to just one with two methods

OnRecyclerItemDownloadButtonClick

That's simply the interface which can be passes do the recycler view with buttons as they are used in the download fragments to implement the download functionality.