A component can specify the layout of its children using the flexbox algorithm. Flexbox is designed to provide a consistent layout on different screen sizes.
You will normally use a combination of `flexDirection`, `alignItems`, and `justifyContent` to achieve the right layout.
> Flexbox works the same way in React Native as it does in CSS on the web, with a few exceptions. The defaults are different, with `flexDirection` defaulting to `column` instead of `row`, and `alignItems` defaulting to `stretch` instead of `flex-start`, and the `flex` parameter only supports a single number.
Adding `flexDirection` to a component's `style` determines the **primary axis** of its layout. Should the children be organized horizontally (`row`) or vertically (`column`)? The default is `column`.
Adding `justifyContent` to a component's style determines the **distribution** of children along the **primary axis**. Should children be distributed at the start, the center, the end, or spaced evenly? Available options are `flex-start`, `center`, `flex-end`, `space-around`, and `space-between`.
Adding `alignItems` to a component's style determines the **alignment** of children along the **secondary axis** (if the primary axis is `row`, then the secondary is `column`, and vice versa). Should children be aligned at the start, the center, the end, or stretched to fill? Available options are `flex-start`, `center`, `flex-end`, and `stretch`.
> For `stretch` to have an effect, children must not have a fixed dimension along the secondary axis. In the following example, setting `alignItems: stretch` does nothing until the `width: 50` is removed from the children.
We've covered the basics, but there are many other styles you may need for layouts. The full list of props that control layout is documented [here](./docs/layout-props.html).
We're getting close to being able to build a real application. One thing we are still missing is a way to take user input, so let's move on to [learn how to handle text input with the TextInput component](/react-native/docs/handling-text-input.html).