MessageAdapter

MessageReceivedViewHolder

View Holder for message sent out from current user, it holds reference to frequent update views and provides helper method to bind data information onto views

MessageSentViewHolder

View Holder for message received from other user, it holds reference to frequent update views and provides helper method to bind data information onto views

<init>

Constructor method to set up MessageAdapter

ACTION_LONG_CLICK_ON_VIEW

unique identifier to specify user long clicked on a view

listener

interface that allow activity to observe user interaction with RecyclerView

messages

list that holds the chat history with another user in the same chat room

sdfDate

It is used to format timestamp from long to String for ChatMessage date

sdfTime

It is used to format timestamp from long to String for ChatMessage time

sender

UID of current user, used to identify message is sent out or received

TAG

TAG is unique identifier to for logging purpose

VIEW_TYPE_MSG_RECEIVED

unique identifier to type of view to be render for ChatMessage object

VIEW_TYPE_MSG_SENT

unique identifier to type of view to be render for ChatMessage object

getItemCount

the method is return number of messages to be display on RecyclerView

getItemViewType

the method return type of view based on current user id view type will determine either message sent or received item layout to be rendered on screen

onBindViewHolder

this method make use of view holder to update display information onto the view

onCreateViewHolder

the method based on view type to render a view and associate the view with respective view holder

setOnRecyclerViewInteractListener

The method provides an interface to allow other class to register itself as observer of user interacting event