fix: spelling and grammar on some react native articles (#23575)

Signed-off-by: Jonathan Grah <theflametrooper@gmail.com>
This commit is contained in:
Jonathan Grah
2019-01-08 00:05:30 +00:00
committed by Huyen Nguyen
parent f0798189c9
commit 181fea9e8e
3 changed files with 40 additions and 43 deletions

View File

@@ -1,29 +1,30 @@
---
title: Component State
---
## Component State
In `Class` components, there is a way to store and manage state built in to React Native.
```javascript
class App extends Component {
constructor () {
constructor() {
super();
this.state = {
counter: 0
counter: 0,
};
}
incrementCount () {
incrementCount() {
this.setState({
counter: this.state.counter + 1
counter: this.state.counter + 1,
});
}
decrementCount () {
decrementCount() {
this.setState({
counter: this.state.counter - 1
counter: this.state.counter - 1,
});
}
render () {
render() {
return (
<View>
<Text>Count: {this.state.counter}</Text>
@@ -37,16 +38,18 @@ class App extends Component {
State is similar to props, but it is private and fully controlled by the component. Here, the `constructor()` method is calling the parent class' constructor with `super();` - **`Component`** is the parent class of `App` because we are using the `extends` keyword. The `constructor()` method also initializes the component's state object:
```
```js
this.state = {
counter: 0
counter: 0,
};
```
The state can be displayed within the component:
```js
{this.state.counter}
{
this.state.counter;
}
```
Or updated by calling:
@@ -55,20 +58,18 @@ Or updated by calling:
this.setState({});
```
**Note:** Aside from its initial creation in your component's `constructor()` method, you should never directly modify the component's state with `this.state = `. You must use `this.setState` as can be seen in the `incrementCount` and `decrementCount` functions above.
**Note:** Aside from its initial creation in your component's `constructor()` method, you should never directly modify the component's state with `this.state =`. You must use `this.setState`, as shown in the `incrementCount` and `decrementCount` functions above.
The count is incremented and decremented by calling the functions passed to the `onPress` handlers just like they would be if you called a click handler from JavaScript on the web.
The count is incremented and decremented by calling the functions passed to the `onPress` handlers, just like they would if you called a click handler from JavaScript on the web.
*ASIDE: In the first example, `<Button>` is a custom component; it's a combination of `<TouchableOpacity>` and `<Text>` from the React Native API:*
_ASIDE: In the first example, `<Button>` is a custom component; it's a combination of `<TouchableOpacity>` and `<Text>` from the React Native API:_
```js
const Button = ({ onPress, children, buttonProps, textProps }) => {
const { buttonStyle, textStyle } = styles;
return (
<TouchableOpacity onPress={onPress} style={[buttonStyle, buttonProps]}>
<Text style={[textStyle, textProps]}>
{children}
</Text>
<Text style={[textStyle, textProps]}>{children}</Text>
</TouchableOpacity>
);
};