cannot update during an existing state transition an existing state trasition (such as within render or another components's constructor). ender methods should be a pure function of props and state

import React, { Component } from 'react';
import {
Button,
StyleSheet,
ImageBackground,
Dimensions,
View,
TextInput,
KeyboardAvoidingView,
ScrollView,
Picker,
TouchableHighlight,
Text
} from 'react-native';
import {Actions} from 'react-native-router-flux'
export default class ComplaintDetailsEdit extends Component<{}> {

constructor(props) {
super(props);
this.state={Relationship:'',Name:'',phno:'',email:'',address:'',complianttype:'',location:'',summary:'',locations:[],ctypes:[],text:''};
}
//state={Relationship:'',Name:'',phno:'',email:'',address:'',complianttype:'',location:'',summary:'',locations:[],ctypes:[]};
renderLocation()
{
fetch('http://wbdemo.in/kscpcr-v1.3/complaints/actions_android/fetch_all_locations.php').then(response => response.json())
.then(data => this.setState({ locations: data }));
return this.state.locations.map(lcnt => )

}
Complaintype()
{
fetch('http://wbdemo.in/kscpcr-v1.3/complaints/actions_android/fetch_all_complaints.php').then(response => response.json())
.then(data => this.setState({ ctypes: data }));
return this.state.ctypes.map(ctyp => );

}
render() {
return (

this.setState({text: itemValue})}>

this.setState({Name})}
onSubmitEditing={()=> this.phoneInput.focus()}/>

this.phoneInput =input}
// onChangeText={phno => this.setState({phno})}
onSubmitEditing={()=> this.EmailInput.focus()} />

this.EmailInput =input}
onSubmitEditing={()=> this.AddressInput.focus()}/>

this.AddressInput =input}
onSubmitEditing={()=> this.ComplaintInput.focus()}/>

this.setState({language: itemValue})}>

{this.Complaintype()}

this.setState({language: itemValue})}>

{this.renderLocation()}

this.ComplaintInput =input}/>

Save and continue

Cancel

);
}
}

const styles = StyleSheet.create({
container: {
flex: 1,
justifyContent:'center',
alignSelf: 'stretch',
width: null,
padding:20,
backgroundColor:"#B73527",

},
formstyle:{
marginTop:0,
backgroundColor:'#F1F1F1',
borderRadius:3,
},
buttonContainer:{
paddingVertical:15,
marginBottom:10,
opacity:20,
},
textInputStyle:{
color:'#000000',
padding:10,
},
ButtonStyle:{
margin:10,
alignItems:'center',
backgroundColor:'#6E1307',
},
btntextInputStyle:{
color:'#FFFFFF',
padding:10,
},
});