在按钮单击时反应本机水平滚动

Question

我是 React Native 的初学者。从image 可以看出，我有一个滚动视图和两个按钮。我已经成功实现了滚动视图，它工作正常，但我也希望他们在按下按钮时自动滚动。我尝试了很多搜索，但没有得到任何有效的东西。所以任何帮助表示赞赏。请在下面找到我的代码。

import React, { Component } from 'react';
import { AppRegistry, StyleSheet, Text, View, Dimensions, ScrollView, Button } from 'react-native';

var screenWidth = Dimensions.get('window').width;

export default class App extends React.Component {
  render() {
    return (
      <View style={styles.MainContainer}>
        <View style={styles.ButtonViewContainer}>
          <View style={styles.ButtonContainer}>
            <Button title="Screen 1" />
          </View>
          <View style={styles.ButtonContainer}>
            <Button title="Screen 2" />
          </View>
        </View>
        <ScrollView
          horizontal={true}
          pagingEnabled={true}
          showsHorizontalScrollIndicator={false}
        >
          <View style={styles.ScrollContainer}>
            <Text style={styles.ScrollTextContainer}>
              Screen 1
              </Text>
          </View>
          <View style={styles.ScrollContainer}>
            <Text style={styles.ScrollTextContainer}>
              Screen 2
              </Text>
          </View>
        </ScrollView>
      </View>
    );
  }
}

const styles = StyleSheet.create({
  MainContainer: {
    backgroundColor: '#abe3a8',
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center'

  },
  ScrollContainer: {
    backgroundColor: '#cdf1ec',
    flexGrow: 1,
    marginTop: 0,
    width: screenWidth,
    justifyContent: 'center',
    alignItems: 'center'
  },
  ScrollTextContainer: {
    fontSize: 20,
    padding: 15,
    color: '#000',
    textAlign: 'center'
  },
  ButtonViewContainer: {
    flexDirection: 'row',
    paddingTop: 35,
  },
  ButtonContainer: {
    padding: 30,
  },
});

Answer 1

我不能保证这是最好的方法，因为我没有经常使用 React Native。

将this.scroll.scrollTo({ x: calculatedStartPositionOfTheScreen}) 添加到您的按钮按下处理程序 https://facebook.github.io/react-native/docs/scrollview#scrollto

例如

<View>
    ...
    <View style={styles.ButtonContainer}>
        <Button title="Screen 1" onPress={() => { this.scroll.scrollTo({ x: 0 }) }} />
    </View>
    <View style={styles.ButtonContainer}>
        <Button title="Screen 2" onPress={() => { this.scroll.scrollTo({ x: screenWidth }) }} />
    </View>
    <View style={styles.ButtonContainer}>
        <Button title="Screen 3" onPress={() => { this.scroll.scrollTo({ x: screenWidth * 2 }) }} />
    </View>
    ...
    <ScrollView
        horizontal={true}
        pagingEnabled={true}
        showsHorizontalScrollIndicator={false}
        ref={(node) => this.scroll = node}
    >
    ...
    </ScrollView>
</View >

对于大型项目中的这个用例，您也可以考虑 https://reactnavigation.org

Answer 2

试试这个。

<View>
    ...
    <View style={styles.ButtonContainer}>
        <Button title="Screen 1" onPress={() => { this.refs.scroll.scrollTo({ x: 0 }) }} />
    </View>
    <View style={styles.ButtonContainer}>
        <Button title="Screen 2" onPress={() => { this.refs.scroll.scrollTo({ x: screenWidth }) }} />
    </View>
    <View style={styles.ButtonContainer}>
        <Button title="Screen 3" onPress={() => { this.refs.scroll.scrollTo({ x: screenWidth * 2 }) }} />
    </View>
    ...
    <ScrollView
        horizontal={true}
        pagingEnabled={true}
        showsHorizontalScrollIndicator={false}
        ref={'scroll'}
    >
    ...
    </ScrollView>
</View >

Answer 3

你可以试试：

onPress = (index) => {
   this.scroll.scrollTo({x: index * screenWidth, y: 0, animated: true})
}

 <Button title="Screen 1" 
    onPress = {() => this.onPress(0)}
 />
 ...
  <Button title="Screen 2" 
    onPress = {() => this.onPress(1)}
 />
 ...
 <ScrollView
      horizontal={true}
      pagingEnabled={true}
      showsHorizontalScrollIndicator={false}
      ref = {re => this.scroll = re}
 >
 </ScrollView>