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Setting Up the Project Files
4:10In this video, we’re going to ensure that the project files are setup properly on your computer and then walk through the start state of the project.
Now that you've seen what
the final project looks like,
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we're going to get the project
files set up on your computer.
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If you've watched online
coding tutorials before,
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I'm sure you've probably done
this kind of setup before.
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I strongly encourage
you to stick around for
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this video just to make sure
everything is in the right place.
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Having a different setup than the one
we follow in the video can cause some
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unnecessary frustration, so
we definitely don't want that to happen.
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I promise I'll keep this short,
sweet, and to the point.
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Go ahead and
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click the link in the teacher's notes to
download the zipped up starter files.
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In them, you'll find six folders in total.
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Each video where we write code will
have a before and after state,
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in case you want to try and challenge
yourself to perhaps watch a video, and
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then go and
implement the changes I make from memory.
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You definitely don't have to do this,
and it's simply an option,
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but this kind of set up helps me learn,
so I figured I'd share it with you.
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In each video,
I will start from the before state and
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end in the after state of the code for
that particular video.
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I've also included to do comments
in the code where I make changes so
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that can be easily found using
Android Studios built in to do window.
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Once you've downloaded the zip of
the project files, make sure that the zip
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files in the location on your computer
where you'd like them to live.
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Once they're there go ahead and
unzip them.
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Within the unzip folders, you will
see sub folders corresponding to each
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video where we write code or
where want to include it's due comment.
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To start, we'll open Android Studio and
then open the folder called 01-exercise.
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Let's have a look around this code.
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In the project, there are two packages.
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One for the login related code and
the other for the messages related code.
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Let's take a peak at
the login package first.
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Once you open the package,
you'll see there are two classes.
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One for the login screen itself,
and a utility class for
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determining if a user is logged in.
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In the LoginActivity, if there's a user
already logged in, I start the messaging
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activity, close the log in activity, and
return so no further code is called.
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Then, I set a listener on the edit
text to log in the user when the Enter
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button is pressed.
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I also set a listener on the log
in button to do the same thing.
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Next, we'll explore the messages package.
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This is where all the fun
FireBase stuff will happen.
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First, I want to show you the Messages
class that will represent a message in our
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Firebase.
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There are a couple of key things here
I want to call your attention to.
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First, notice that there is
a no arguments constructor.
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Firebase requires this in
order to deserialize objects.
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You'll also notice
the @IgnoreExtraProperties
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annotation on this class.
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There will be an error with
that annotation at first, but
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we'll fix this shortly.
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That annotation does
exactly what it looks like.
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It ignores properties that
don't map the class fields.
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In other words, if there is a method for
getting a value that doesn't directly
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correspond to a class field, it's ignored
when setting your data to Firebase.
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Next, we'll look at the MessagingActivity.
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We also have simple classes for
MessageAdapter and MessageViewHolder.
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But those are simply boiler plate
required to populate a recycler view.
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And I will leave it up to you
to explore those classes.
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Within the MessagingActivity, I've set
the adapter on the recycler view and
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wired up the button to send a message and
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the edit text to send a message when
a user clicks the Enter button.
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Currently, the activity will show a toast
when we attempt to send a message, but
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we will update that behavior soon.
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There are also methods below for
clearing a text of the edit text,
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hiding the keyboard, and
scrolling to the most recent message.
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Those methods are all simply for
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a better user experience and
certainly aren't required by Firebase.
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Let's run the starter project and
see what it looks like.
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I'm going to comment out the Firebase
annotation on our Message class since
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I haven't yet included the Firebase
library in this project.
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But, again, we'll fix that very soon.
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When you run this project, you'll
first see the username entry screen.
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After you provide a username,
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you'll see a screen where a list of
messages will eventually be displayed.
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For now, if we type a message and
hit send.
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We'll see that the message goes away,
but isn't actually sent anywhere.
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In the next video, we'll learn how to
create a Firebase project in the Firebase
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console, taking the first step to sending
your message to everyone in real time.
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