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We said that we would plug the reader's name into the story, so let's see how to do it using the String.format() method.
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A while ago we talked about taking
the name that we get from the user, and
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then plugging it directly into our story.
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Let's do that now.
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Instead of just sending the text in the
text view directly from our page object,
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we're going to search for a specific
string, replace it with our users name.
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So let's create a new string variable
to hold the text of our story.
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String pageText = getString and then we
can get it right from string resources.
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And again, from the page object,
we want to get the Text ID associated for
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the given page.
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We'll use this page text variable
to set the text in our text view.
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But we're going to manipulate
it before we pass it in.
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So the code we're gonna write here is some
simple Java code that you may be familiar
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with from our Java courses.
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But if not, we'll talk it over briefly.
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Basically it's just a search and replace
for that special sequence we saw earlier.
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I'm gonna add a few lines here and
bump my code up.
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And now on a new line type pageText
equals String with a capital s
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.format, then for
the first parameter let's use pageText,
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and for the second parameter
let's pass in the name.
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But wait.
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I don't remember if this
name is available down here.
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We haven't passed it
into our loadPage method.
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And let's see,
up here we're setting it, but
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here's where we declare it
in the onCreate method.
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Let's make this a member variable instead,
that we can access both in here and
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onCreate, and in the loadPage method.
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I'd rather make it a member variable
because we're gonna use the same name in
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a couple of different pages.
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So, I'll just delete string, and then up
here at the top say private String name.
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And now we can set it here,
and use it down here, cool.
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So in this new line of code we are going
to format pageText by passing in the name.
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And then we'll store the reformatted
result back into pageText.
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So we'll work on it here and then we'll
store the result back in this variable.
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Let's take a quick look at
the string documentation for
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Java from the Oracle website.
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So here we have the string class.
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And if we scroll down a little bit
we can go to the method summary, and
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then here we find two
different format methods.
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The first one has a Locale, but
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we just want the second one here that
takes a String and Object parameters.
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This format method is a Static method,
which is why we call it in a from a String
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class, and
not from a specific instance of a String.
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This concept of static versus instance
methods maybe a little confusing,
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based on how familiar you are with Java.
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But static methods like this mean
that we don't need an actual
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instance of a string to call it, which is
why we're able to just use the class name.
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A basic idea here is we can plug in
special characters in our string and
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this method will replace those special
characters when it finds a match
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with whatever arguments we provide.
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So let's click on the format string here,
to see some examples.
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So here, we have a birthday example
with some special placeholders.
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Percent one with a dollar sign and
a specific code which stands for
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month, then day, and
then year in this example.
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So if we go back to our story code,
let's go to our string resources and
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I've already plugged in the appropriate
characters we need for page zero.
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So I'm going to turn on that
soft wrap feature again.
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We click on View,
Active Editor, Use Soft Wraps.
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Now, all the text for page0,
will wrap on the screen.
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And here you can see %1$s.
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%1 is the order number of the parameter.
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We could have multiple parameters but we
only have one, so it's just gonna be %1.
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If we had a second parameter,
for example, it would be %2.
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And then the $s, is just for
a simple string.
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So this will say, "Help me,
user, you're my only hope".
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This same sequence shows up in page5 too,
if we scroll down here,
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we see our favorite android,
and again, we have %1$s.
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So let's go back to the story activity.
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The cool thing about this method
is that if no match is found,
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then the name won't be plugged, which is
why we can call this on every single page.
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So let's add a comment just to clarify.
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Add the name if the placeholder is
included, and it won't add if it's not.
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What else do we need to do here.
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We need to set the text view
with this modified text.
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On the next line type
storyTextView.setText, that's the method
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to set this text of course, and we can
pass in the newly formatted pageText.
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We also need to set the text for
each button.
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That's easy enough.
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On a new line,
type choice1Button.setText, and
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then we can pass in the string
ID as the parameter here,
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page.getChoice1().getTextId().
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Notice that setText is
overloaded on these widgets.
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So the first one, takes an actual string,
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and the second one here,
takes the ID of a string resource.
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Let's do the same thing for choice2Button.
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setText(page.getChoice2().getTextId(), and
finish it off.
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Right, let's run this, and
we should be able to see all four
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of the elements on our screen
with the appropriate page0 text.
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There it loads, I enter my name,
start my adventure and
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we've got it all here and check it out
there's my name showing up in the story.
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All right.
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We should also verify that our scroll
view is working by running this on
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emulator with a smaller screen size.
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So back here in Android studio,
we're gonna stop the current process.
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And I am gonna click on AVD Manager.
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I currently don't have an emulator
with a smaller screen, so
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I am gonna Create a New Virtual Device,
and
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I'll take the Nexus One simply because it
has the smallest screen size on my list.
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I'm running the X86 version of the
emulator, I'll pick Nougat, and hit Next.
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Finish this, and now what I want to do is
start it, and when I run the app again,
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I'll make sure I go into this
emulator instead of the Pixel.
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All right my emulator just finished,
I'm gonna close this and
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now if I click run I
can pick the Nexus One.
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I'm only gonna do this one time, though,
so I'm going to uncheck this and
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I'll put it back on the Pixel.
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All right, so
this fits okay on the small screen.
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Type my name, start the adventure, and now
you can see that the text is running down.
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And if we scroll up we can
read the rest of it, and
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sure enough, our name still shows up.
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Cool.
All right just like we want it,
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the scroll view is scrolling
both the image and
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the text view while the buttons remain
in place at the bottom of the screen.
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Very nice.
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All right, so we have successfully
loaded some story data into our view and
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we've got the scroll view
working just like we wanted to.
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Coming up in the next section, we'll
get the rest of the story working, and
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we'll also take a look at how to
properly navigate within an Android App.
6:31
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