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Activities (and many other things in Android) are started using an object called an Intent. The intent of this Intent is to start another Activity. :)
So, when you as a person intend to do
a task, it means that you've thought about
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what you wanna do, and
you're intent is to do it.
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You just need to start and
maybe you need a little help.
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In Android, it's the same basic idea,
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but it's wrapped up in an intent
object that we can use in code.
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An intent is what we use when we intend
to do something in an Android app.
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We usually use them to start a new task,
and
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that task can be something like
starting a new activity, or
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maybe handing something off to another app
like a video player, or a messaging app.
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Back in our code, let's declare a new
intent object named, simply, intent.
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We'll set it equal to a new Intent,
with parentheses, and add a semicolon.
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Now, there are a few different
constructors we can use.
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So, if we go back between the parentheses,
we can hit Cmd+P on a Mac, or
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Ctrl+P on Windows, to bring up some help.
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We're going to start a new activity,
which is defined in a class file.
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Thus, we want the fourth option shown
here, that accepts the current context,
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and a class as a parameter.
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Remember that context is
really important in Android.
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We discussed it briefly before, but
it is essentially the specific context or
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environment within which
our code is running.
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This code is in an activity, and
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the activity class is a sub
class of the context class.
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So we can use the current
activity as our context.
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This is easily achieved
with the this keyword.
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And in this case,
it's now referring to this current class.
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There are other ways
to access the context.
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For example,
we could type getApplicationContext,
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which is a method available
in the activity class.
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But let's undo that,
go with this, and now for
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the second parameter, we want
the activity class that we want to start.
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So we type StoryActivity and then we type
.class to reference the actual class.
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When our app is actually running,
it needs the class object
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rather than simply the name which
is why we use this class property.
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Okay, next, just one more line of code.
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We need to express this intention somehow.
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This is often done using the method
from the activity base class called,
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startActivity.
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And look at that.
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It takes an intent as its parameter.
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Type that and try it out,
and see what happens.
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Okay, we can type a name again.
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Hit enter.
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Start the adventure.
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All right, and we're taken to
our new blank story activity.
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