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In this video we'll see how to format numbers differently based on the locale of our users!
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The app looks great in Spanish.
0:00
But if we pick a color, like purple,
then we see the price as $19.99.
0:02
And while we do want to
display the price in dollars,
0:09
this isn't the correct way to format
a number for a Spanish audience.
0:12
In Spain, and most of Europe and
0:15
South America, instead of using a dot
as a decimal mark, they use a comma.
0:17
So this should really be 19,99.
0:22
One way we could do this, would be to set
up a switch statement based on the locale
0:25
of the user, and then manually swap
out dots for commas, and vice versa.
0:30
But that would be a ton of work, and
0:35
requires to know the preference of
each country we want to support.
0:36
Luckily, Android's got an easy way for
0:41
us to deal with this in
the number format class.
0:43
Let's open up our main activity, And
0:46
at the bottom of onCreate,
let's create a variable for our price,
0:50
float price, and
let's set it equal to 19.99f.
0:56
Then, on the next line let's create
a new NumberFormat variable,
1:02
Named numberFormat, and
let's set it equal to NumberFormat..
1:08
And here we can see the different types
of number format that we can create.
1:15
In addition to the standard
getInstance() method,
1:19
we can also get a NumberInstance() for
formatting a float, a CurrencyInstance(),
1:22
an IntegerInstance(),
and a PercentInstance().
1:26
Let's go with getCurrencyInstance().
1:30
Next, let's create a new string
variable to hold our formatted price,
1:32
String priceString, and let's set it
equal to numberFormat.format() and
1:38
pass in our price.
1:43
Finally, let's call priceTextView.setText,
1:47
and pass in our price string.
1:53
Now if we run the app, And
1:56
pick a color, we've got 19,99, awesome.
2:00
But now it's in euro's Instead of dollars,
2:05
which makes it a completely
different price.
2:09
For now, we're only pricing our paint in
dollars, so we'll need to find a way to
2:12
get back to the dollar symbol while
keeping the formatting we need.
2:16
Also, a quick note,
depending on the device you have,
2:20
just changing the language might not
be enough to update your locale.
2:23
Also, some devices just don't have
that many languages available.
2:28
For example,
my Note 4 only has five language choices.
2:32
So if you're unable to do
something that I'm doing,
2:36
I'd suggest switching to an emulator.
2:39
Okay, so we need to find a way
to keep the formatting, but
2:41
instead use the dollar symbol.
2:44
So how about,
instead of using getCurrencyInstance(),
2:46
we use getNumberInstance().
2:51
And then when we're setting
our formatted price,
2:53
we just tack on a dollar sign at the end.
2:57
But actually, if we're hard coding
the currency sign to follow the price,
3:00
that means it won't be quite right for
the English version,
3:04
where the currency symbol
should be before the price.
3:07
Luckily, Android's got
us covered here as well.
3:10
Let's start by undoing
adding the dollar sign, and
3:12
changing this back to
getCurrencyInstance().
3:16
Then, what we need to do,
is set the currency symbol for
3:18
our number format to always be US dollars.
3:22
To do this, let's add a line below
where we declare our number format, and
3:25
then call this set currency method
on our number format object, so
3:29
numberFormat.setCurrency().
3:33
And then we need to pass in a currency.
3:36
So let's pass in Currency.getInstance(),
which requires a country code.
3:38
So let's pass in "USD".
3:44
Now let's run the app again, And
if we pick a color, perfect!
3:46
We've got 19,99 and then a dollar sign,
and if we change our language back
3:52
to English, The United States version,
3:58
Then we've got a dollar sign, then 19.99.
4:08
Great job.
4:12
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