javascript - 通过 React Native 更改图标 activeIndex

Question

如何通过 React Native 更改图标 activeIndex？我正在使用native-base模块，但不起作用，只是activeIndex == 0处于活动状态，我的功能不起作用。

代码：

import {Icon, Button} from 'native-base';
type Props = {};
export default class App extends Component<Props> {
  constructor(props) {

    super(props);
    this.segmentClicked = this.segmentClicked.bind(this);
    this.state = {
      activeIndex: 0
    }
  }

  segmentClicked = (index) => {
    this.setState = ({
      activeIndex: index
    })
  }
  render() {
    return (
      <View style={styles.container}>
        <View style={{flexDirection: 'row', justifyContent: 'space-around', borderTopWidth: 1, borderTopColor: '#eae5e5'}}>
          <Button
            onPress={this.segmentClicked(0)}
            active={this.state.activeIndex == 0}
          >
            <Icon name='ios-apps-outline'
              style={[this.state.activeIndex == 0 ? {} : {color: 'gray'}]}
            />
          </Button>
          <Button
            onPress={this.segmentClicked(1)}
            active={this.state.activeIndex == 1}
          >
            <Icon name='ios-list-outline'
              style={[this.state.activeIndex == 1 ? {} : {color: 'gray'}]}
            />
          </Button>
          <Button
            onPress={this.segmentClicked(2)}
            active={this.state.activeIndex == 2}
          >
            <Icon name='ios-people-outline'
              style={[this.state.activeIndex == 2 ? {} : {color: 'gray'}]}
            />
          </Button>
          <Button
            onPress={this.segmentClicked(3)}
            active={this.state.activeIndex == 3}
          >
            <Icon name='ios-bookmark-outline'
              style={[this.state.activeIndex == 3 ? {} : {color: 'gray'}]}
            />
          </Button>
        </View>
      </View>
    );
  }
}

标签： javascriptreactjsreact-nativetabsnative-base

Answer 1

编写时正在调用该函数this.segmentClicked(1)。相反，您想提供一个在按下时将调用的函数。Button

例如，您可以创建一个新的内联箭头函数。

<Button
  onPress={() => this.segmentClicked(1)}
  active={this.state.activeIndex == 1}
>
  <Icon name='ios-list-outline'
    style={[this.state.activeIndex == 1 ? {} : {color: 'gray'}]}
  />
</Button>

您还必须调用该setState函数，而不是为其分配新值。

segmentClicked = (index) => {
  this.setState({
    activeIndex: index
  });
}