react-native/local-cli/templates/HelloNavigation/components/KeyboardSpacer.js

118 lines
2.9 KiB
JavaScript

'use strict';
/* @flow */
import React, { PropTypes, Component } from 'react';
import {
Platform,
View,
Keyboard,
LayoutAnimation,
UIManager,
} from 'react-native';
type Props = {
offset?: number,
}
type State = {
keyboardHeight: number
}
// Consider contributing this to the popular library:
// https://github.com/Andr3wHur5t/react-native-keyboard-spacer
/**
* On iOS, the software keyboard covers the screen by default.
* This is not desirable if there are TextInputs near the bottom of the screen -
* they would be covered by the keyboard and the user cannot see what they
* are typing.
* To get around this problem, place a `<KeyboardSpacer />` at the bottom
* of the screen, after your TextInputs. The keyboard spacer has size 0 and
* when the keyboard is shown it will grow to the same size as the keyboard,
* shifting all views above it and therefore making them visible.
*
* On Android, this component is not needed because resizing the UI when
* the keyboard is shown is supported by the OS.
* Simply set the `android:windowSoftInputMode="adjustResize"` attribute
* on the <activity> element in your AndroidManifest.xml.
*
* How is this different from KeyboardAvoidingView?
* The KeyboardAvoidingView doesn't work when used together with
* a ScrollView/ListView.
*/
const KeyboardSpacer = () => (
Platform.OS === 'ios' ? <KeyboardSpacerIOS /> : null
);
class KeyboardSpacerIOS extends Component<Props, Props, State> {
static propTypes = {
offset: PropTypes.number,
};
static defaultProps = {
offset: 0,
};
state: State = {
keyboardHeight: 0,
};
componentWillMount() {
this._registerEvents();
}
componentWillUnmount() {
this._unRegisterEvents();
}
_keyboardWillShowSubscription: { remove: Function };
_keyboardWillHideSubscription: { remove: Function };
_registerEvents = () => {
this._keyboardWillShowSubscription = Keyboard.addListener(
'keyboardWillShow',
this._keyboardWillShow
);
this._keyboardWillHideSubscription = Keyboard.addListener(
'keyboardWillHide',
this._keyboardWillHide
);
};
_unRegisterEvents = () => {
this._keyboardWillShowSubscription.remove();
this._keyboardWillHideSubscription.remove();
};
_configureLayoutAnimation = () => {
// Any duration is OK here. The `type: 'keyboard defines the animation.
LayoutAnimation.configureNext({
duration: 100,
update: {
type: 'keyboard',
}
});
}
_keyboardWillShow = (e: any) => {
this._configureLayoutAnimation();
this.setState({
keyboardHeight: e.endCoordinates.height - (this.props.offset || 0),
});
};
_keyboardWillHide = () => {
this._configureLayoutAnimation();
this.setState({
keyboardHeight: 0,
});
};
render() {
return <View style={{ height: this.state.keyboardHeight }} />;
}
}
export default KeyboardSpacer;