我在玩react native,有一种奇怪的行为.
当我试图显示ActitvityIndicator for Android将其animating属性设置为true,且showProgress
变量处于状态时,如果变量的开头为false,则该属性不起作用.
在下面的示例中,如果ActivityIndicator动画属性开始为true,则按钮会使ActivityIndicator正确隐藏或显示.
import React, { Component } from 'react';
import {
Text,
View,
StyleSheet,
TextInput,
TouchableHighlight,
ActivityIndicator
} from 'react-native';
export class Login extends Component {
constructor(props) {
super(props);
this.state = {
showProgress: true
};
}
render() {
return (
<View>
<TouchableHighlight onPress={this.progressOff.bind(this)}>
<Text>progressOff</Text>
</TouchableHighlight>
<TouchableHighlight onPress={this.progressOn.bind(this)}>
<Text>progressOn</Text>
</TouchableHighlight>
<ActivityIndicator animating={this.state.showProgress} size="large"/>
</View>
);
}
progressOff() {
this.setState({showProgress: false});
}
progressOn() {
this.setState({showProgress: true});
}
}
但是如果我使用下面的代码,动画属性以false开头,那么让ActivityIndicator出现的按钮就不起作用了:
import React, { Component } from 'react';
import {
Text,
View,
StyleSheet,
TextInput,
TouchableHighlight,
ActivityIndicator
} from 'react-native';
export class Login extends Component {
constructor(props) {
super(props);
this.state = {
showProgress: false
};
}
render() {
return (
<View>
<TouchableHighlight onPress={this.progressOff.bind(this)}>
<Text>progressOff</Text>
</TouchableHighlight>
<TouchableHighlight onPress={this.progressOn.bind(this)}>
<Text>progressOn</Text>
</TouchableHighlight>
<ActivityIndicator animating={this.state.showProgress} size="large"/>
</View>
);
}
progressOff() {
this.setState({showProgress: false});
}
progressOn() {
this.setState({showProgress: true});
}
}
我错过了什么?