React-Native ViewPager goToPage Not Working - react-native

Question

import ViewPager from 'react-native-viewpager';
constructor(props){
super(props);
this._renderPage = this._renderPage.bind(this);
this._renderRowSablon = this._renderRowSablon.bind(this);
this.PageChange = this.PageChange.bind(this);
this.count = 0;
this.state = {
count: 0,
info : this.props.values,
page: 0,
pages:pages,
}
}
PageChange(x){
switch(x){
case 'next':
if( this.state.count< (this.state.info.sayfa - 1) ){
this.viewpager.goToPage(this.state.count + 1);
this.setState({count: this.state.count+ 1});
}
break;
}
}
render(){
<View style={{flex:1}}>
<ViewPager
ref={(viewpager) => {this.viewpager = viewpager}}
dataSource={this.state.dataSource}
renderPage={this._renderPage}
onChangePage={this._pageChange}
isLoop={false}
renderPageIndicator={false}
locked={true}
autoPlay={false}/>
</View>
<View style={{flex:1}}>
<TouchableHighlight onPress={() => { this.PageChange('next'); }}>
<Text>Next</Text>
</TouchableHighlight>
</View>
}
When the setState function is cleared, page change is taking place. When the setState function is added (as above) setState works but the page change (gotoPage) does not work. Does not show error / warning What exactly is the problem?

Answer 1

It seems that you are out of scope. When using arrow functions, the scope of 'this' becomes lexical.
Try changing <TouchableHighlight onPress={() => { this.PageChange('next'); }}>
to <TouchableHighlight onPress={this.PageChange('next')}>
See this question:
React-Native: Cannot access state values or any methods declared from renderRow