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RN中要解決鍵盤遮擋輸入框的問題其實有挺多方式,在這裡只是記錄其中的一些個人實際開發中使用到的。
方式一、使用scrollTo方法,這也是最簡單最粗暴的,只是需要計算scrollview滾動的距離,並且處理一些體驗的bug問題。大致思路是:組件render方法中使用scrollview,並且設定scrollview的keyboardShouldPersistTaps={true}(此步一定不能少,如果缺少該屬性,接下來的一步將會不起作用),然後在scrollview中用一個view作為container包裹所有剩餘的子視圖,比如Text,TouchableHighlight之類的,並且用onStartShouldSetResponderCapture截取該view的事件,用以解決當點擊頁面上的按鈕時,第一次點擊只會收合鍵盤,第二次點擊才會響應按鈕方法的bug。然後在TextInput的onFocus方法中滾動scrollview,在onEndEditing中恢複scrollview的滾動。以下是在具體實現中的代碼。
render方法的實現:
render:function() {
return(
<View style={styles.container}>
<NavigationBar title={‘綁定手機號‘} onBackPress={this.onBackPress}/>
<ScrollView ref=‘scroll‘ keyboardShouldPersistTaps={true} >
<View style={styles.content} onStartShouldSetResponderCapture={(e) => {
const target = e.nativeEvent.target;
if (target !== React.findNodeHandle(this.refs.phoneInput) && target !== React.findNodeHandle(this.refs.codeInput)) {
this.refs.phoneInput.blur();
this.refs.codeInput.blur();
}}}>
<TextInput
style = {styles.cardNumText}
ref = ‘phoneInput‘
onFocus={this.scrollViewTo.bind(this)}
onEndEditing={()=>{this.refs.scroll.scrollTo(0)}}
onChange = {this.cardNumberTextChanged.bind(this)}
placeholder = ‘請輸入預留手機號‘
placeholderTextColor = ‘#481A5C‘
keyboardType = ‘numeric‘
/>
<View style = {styles.lineView}></View>
<TouchableHighlight style = {styles.topButton} underlayColor=‘#9B9B9B‘ onPress = {this.jumpToNextPage.bind(this)}>
<Text style = {styles.buttonText}>發送驗證碼</Text>
</TouchableHighlight>
<TextInput
style = {styles.cardNumText}
ref = ‘codeInput‘
onFocus={this.scrollViewTo.bind(this)}
onEndEditing={()=>{this.refs.scroll.scrollTo(0)}}
placeholder = ‘輸入驗證碼‘
placeholderTextColor = ‘#999‘
onChange = {this.cardNumberTextChanged}
keyboardType = ‘number-pad‘
/>
<View style = {styles.lineView}></View>
<Text style = {styles.protectText}>
XXXXXXXXXXXXXXXXXXX
</Text>
<TouchableHighlight style = {styles.downButton} underlayColor=‘#481A5C‘ onPress = {this.jumpToNextPage.bind(this)}>
<Text style = {styles.buttonText}>下一步</Text>
</TouchableHighlight>
</View>
</ScrollView>
</View>);
}
onFocus時調用的scrollViewTo方法的實現:
scrollViewTo:function(e){
let target = e.nativeEvent.target;
let scrollLength = 100;
if (target=== React.findNodeHandle(this.refs.codeInput)) {
scrollLength = 160;
}
this.refs.scroll.scrollTo(scrollLength);
},
方式二、使用View包裹時,通過設定View的marginTop屬性並且結合動畫來實現:初始化一個state對象的值viewMarginTop用於設定Animated.View的marginTop,在textInput的onfocus時改變viewMarginTop的值,在onEndediting時恢複或者設定新的marginTop。具體為首先引入Animated,並且初始化state方法。(state內值的變化會觸發介面上相關元素的再次熏染,具有reactivecocoa的相同的作用)
getInitialState: function () {
return {
viewMarginTop: new Animated.Value(0),
};
},
在需要上升的視圖中使用Animated.View,設定其mairginTop為viewMarginTop
<Animated.View style={{marginTop:this.state.viewMarginTop}}>
//當然不建議將樣式寫在這裡,這樣會導致每次熏染都建立一次樣式,你應該將樣式定義到StyleSheet中
//your Views and component
</Animated.View>
然後在onFucos的方法中用動畫改變viewMarginTop的值,如下
Animated.timing(
this.state.viewMarginTop,
{
toValue: 160,
duration: 250,
}
).start();
要恢複只需要在onEndediting中用同樣的原理恢複viewMarginTop的值即可.
方式三、通過監聽scrollview上鍵盤的出現和消失,在出現和消失方法中設定某個state值的變化,來設定scrollview的contentInset,該方法只是在github上看過,具體本人並沒有用過即:
1.在頁面熏染完時添加監聽
componentDidMount: function () {
// Keyboard events監聽
DeviceEventEmitter.addListener(‘keyboardWillShow‘, this.updateKeyboardSpace)
DeviceEventEmitter.addListener(‘keyboardWillHide‘, this.resetKeyboardSpace)
},
componentWillUnmount: function () {
// TODO: figure out if removeAllListeners is the right thing to do
DeviceEventEmitter.removeAllListeners(‘keyboardWillShow‘)
DeviceEventEmitter.removeAllListeners(‘keyboardWillHide‘)
},
getInitialState: function (props) {//初始設定變數
this.viewIsInsideTabBar = false
return {
keyboardSpace: 0,
}
},
// Keyboard actions
updateKeyboardSpace: function (frames) {
const keyboardSpace = frames.endCoordinates.height//擷取鍵盤高度
this.setState({
keyboardSpace: keyboardSpace,
})
},
resetKeyboardSpace: function () {
this.setState({
keyboardSpace: 0,
})
},
//設定scrollview的contentInset
<ScrollView
ref=‘keyboardView‘
keyboardDismissMode=‘interactive‘
contentInset={{bottom: this.state.keyboardSpace}}
showsVerticalScrollIndicator={true}
</ScrollView>
React-native鍵盤遮擋輸入框問題的解決