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There are some Gotland concepts and styles used in compose that we need to talk about.

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Some we already discussed in the previous column lectures but need to go over them again.

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And others you might be hearing for the first time because Jetpack Compose is built around Scotland

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specific styles we need to get familiar with so that we can easily understand the APIs Campos has available

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for us.

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So default arguments are initial values given to a method parameter is at the point of creation.

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So for example, the Button Composable is created with several parameters for which most of them have

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initial values or default arguments, making it possible to call a button composable without needing

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to provide values for all of them.

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So let's look at the use of button elements.

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So the Button Composable requires on click and content arguments.

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When we look back in the previous slide, we see that both declarations had no assignment symbol that

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is this equal sign, making it necessary to provide them when the method is called and others are optional,

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depending on the requirements you have for the composable.

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So you see here there are many that have an equal sign, which means they have something defined to

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them by default.

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All right.

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Another concept is higher order functions, which are functions that accept order functions as an argument

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and compose uses them a lot.

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Let's look at this example with the court block we can directly at the function body with what should

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happen when the button is clicked, and that is using a function as an argument, which is possible

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with the help of Lambda.

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So we can also decide to create a normal functioning and call it within the block itself.

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So we have used trailing lambdas already in previous lectures.

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They are a special syntax for calling higher order functions whose power meter is a lambda outside of

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parentheses.

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So the romance requires a content parameter, which is a London.

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So this code works but can look better when placed outside of the parentheses.

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This is an example of a trading lumber, which is outside the role parentheses, and therefore the parentheses

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is removed.

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This way, it looks more concise and less cumbersome.

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So let's compare that you see.

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Like this.

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So we didn't need to define the content in the brackets and so forth.

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So next, our delegated properties.

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These are variables declared with the by keyword and are usually associated with a state.

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For example, the name state is declared using the remember keyword, and then it's used within the

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text field to track the value directly when it changes.

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We will see more of this in coming lectures.

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And then destructing data classes, so destructing simply means creating multiple variables at once,

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an example, this one creating reference ID and constraint layout as we have used before with create

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refs, we can create different IDs at a goal and use them as required, so we don't need to set them

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up all one by one.

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A very important additional aspect of what we need to look at our code routines, which offer asynchronous

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programming support and can suspend execution without blocking the main threat and jetpack compose is

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a reactive UI framework and changes its state as the user interacts with it.

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These states can require heavy processing and need to be performed without blocking the UI.

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Threat Compose makes this easier by embracing code routine at API level rather than using callbacks.

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So let's look at an example here.

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A snack bar function is a call routine function, and we can easily call the Remember code routine scope

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and then launch a block for show snack bar.

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So showing the snack bar.

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We're going to learn more about all of the idiomatic Cortland codes in the coming lectures.

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All right, so this was a little overview slash introduction to new topics just to give you a first

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look at them.

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We are going to work with those in more depth, obviously.

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So see you in the next couple of videos.