All language subtitles for 13. Challenge 3 Solution

We know that the simplest type of Dart functions look like this. Where we have a keyword void
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at the beginning, we have the name of the function,
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we have a set of parentheses which will keep empty,
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and then we have our curly braces.
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And inside these curly braces are all of the instructions that are repeated that we need to use in different
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places in our code. And when we want to call this function to activate it,
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we call it by its name like so. Applying that to our code,
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let's go up here and create a new function. To start off with the void keyword, we'll call it,
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you call it anything you want, but let's call it changeDiceFace.
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And I'm going to add a set of empty parentheses.
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Now it's a complete building our function,
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all we need to add now are a set of curly braces.
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And it's inside these curly braces where we'll add the blocks of code which are repeated across our
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code namely updating our leftDiceNumber and updating our rightDiceNumber.
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You can see that all of this is the same.
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So let's cut that out of the onPressed and let's paste it into our new function. And we can now, instead
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of having to write all those lines of code, we can simply call it by its name, which is changeDiceFace.
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So now when our flat button gets pressed, the onPressed listener gets triggered and it looks to find this
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function with the name of changeDiceFace. It finds it right here and it calls set state, changes the
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leftDiceNumber, changes the rightDiceNumber.
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So now we can put that in here as well and we're gonna call changeDiceFace down here too.
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And now this code is no longer repeated in two places.
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Or maybe if you had more dice, there'd be more places that it would be needed. Now,
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if you were wondering why we couldn't take out the expanded widget and the repeated flat button widget
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or the repeated onPressed, we're going to answer that in a few modules because we need to learn a bit
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more about widgets before we can do that. In the next lesson,
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I've got one final boss level challenge for you. And it's to build an app of your own.
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So once you're ready, head over there and be ready to face off the end of level boss. And I'll see you
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on the next module.