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How do i get specific elements from webservice

I want to get specific the first two elements from a webservice and print it to a console it is returning me 1000 items. Can anyone guide me on how I can print only the first two elements
import React from "react";
import {StyleSheet,View,ActivityIndicator,FlatList,Text,TouchableOpacity} from "react-native";
export default class Source extends React.Component {
static navigationOptions = ({ navigation }) => {
return {
title: "Source Listing",
headerStyle: {backgroundColor: "#fff"},
headerTitleStyle: {textAlign: "center",flex: 1}
};
};
constructor(props) {
super(props);
this.state = {
loading: false,
items:[]
};
}
FlatListItemSeparator = () => {
return (
<View style={{
height: .5,
width:"100%",
backgroundColor:"rgba(0,0,0,0.5)",
}}
/>
);
}
renderItem=(data)=>
<TouchableOpacity style={styles.list}>
<Text style={styles.lightText}>{data.item.name}</Text>
<Text style={styles.lightText}>{data.item.email}</Text>
<Text style={styles.lightText}>{data.item.company.name}</Text>
</TouchableOpacity>
render(){
{
if(this.state.loading){
return(
<View style={styles.loader}>
<ActivityIndicator size="large" color="#0c9"/>
</View>
)}}
return(
<View style={styles.container}>
<FlatList
data= {this.state.dataSource}
ItemSeparatorComponent = {this.FlatListItemSeparator}
renderItem= {item=> this.renderItem(item)}
keyExtractor= {item=>item.id.toString()}
/>
</View>
)}
}
const parseString = require('react-native-xml2js').parseString;
fetch('http://192.168.200.133/apptak_service/apptak.asmx/Get_Item_Master')
.then(response => response.text())
.then((response) => {
parseString(response, function (err, result) {
console.log(response[0],response[1])
});
}).catch((err) => {
console.log('fetch', err)
})
const styles = StyleSheet.create({
container: {
flex: 1,
backgroundColor: "#fff"
},
loader:{
flex: 1,
justifyContent: "center",
alignItems: "center",
backgroundColor: "#fff"
},
list:{
paddingVertical: 4,
margin: 5,
backgroundColor: "#fff"
}
});
I want it to be print on the console then I will modify it later to display it on the app. I am struggling to get this done Please help

You are parsing the response as string. If you want to print the first two item in console, you can do it like this bellow:
fetch('http://192.168.200.133/apptak_service/apptak.asmx/Get_Item_Master')
.then((response) => {
console.log(response.data[0],response.data[1])
}).catch((err) => {
console.log('fetch', err)
})

Perhaps what you need is the result?
parseString(response, function (err, result) {
console.log(result) // not console.log(response)?
});
Using JavaScript
fetch("http://192.168.200.133/apptak_service/apptak.asmx/Get_Item_Master")
.then((r) => r.text())
.then((t) => (new window.DOMParser()).parseFromString(t, "text/xml"))
.then((d) => console.log(d))
.catch((e) => console.error(e));

React Native Redux causing whole page to render upon calling function

I have an issue with React Native Redux where I am calling a Redux action from the onChangeText function from inside a TextField. Normally, an update like this would only cause the TextField itself to update, however the whole page is being re-rendered upon each call of the function.
Here is the code for the TextField. The method in question is this.props.updateURL(value)
<TextField label='Server'
value={this.props.profile.url}
labelFontSize={textFont(16)}
tintColor='#B3B2B6'
autoCapitalize="none"
autoCorrect={false}
returnKeyType={'next'}
blurOnSubmit={false}
autoFocus={!this.props.profile.edited}
style={styles.inputStyle}
selectionColor={CUSRSOR_COLOR}
editable={!this.props.profile.edited}
onChangeText={async value => {
this.props.updateURL(value)
}}
renderAccessory={()=>{
return(<TouchableOpacity onPress={this.handleScanPress} >
<Image source={ImgScan} style={{height: 25, width: 25, overflow:'visible', marginBottom:20, marginRight: 10}}/>
</TouchableOpacity>);
}}
>
</TextField>
This is for the Redux methods mapStateToProps and mapDispatchToProps:
const mapStateToProps = (state) => {
return {
profile : state.profileReducer,
deviceUid: state.GlobalReducer.deviceUid,
locationsList: state.LogsReducer.locationList,
errorList: state.ErrorsReducer.failedList,
watermarkText: state.GlobalReducer.watermarkText,
alertPresent: state.LogsReducer.alertPresent
}
};
const mapDispatchToProps = (dispatch) => {
return {
updateURL : (url) => dispatch(updateURL(url)),
updateUserName : (userName) => dispatch(updateUserName(userName)),
updatePassword : (password) => dispatch(updatePassword(password)),
updateDeviceName : (deviceName) => dispatch(updateDeviceName(deviceName)),
allFieldsEntered : (url,userName,password) => dispatch(allFieldsEntered(url,userName,password)),
loginDevice: (url,userName,password,deviceName,deviceId,navigation,existingUser) => dispatch(callLoginApi(url,userName,password,deviceName,deviceId,navigation,existingUser)),
updateFailureMessage: (message) => dispatch(updateFailureMessage(message)),
showLoader: () => dispatch(showLoader()),
hideLoader: () => dispatch(hideLoader()),
updateRegistrationSuccess: (value) => dispatch(updateRegistrationSuccess(value)),
checkForInternet: () => dispatch(checkConnectivity()),
getProfileDetails: async(isToken) => await dispatch(fetchProfileDetails(isToken)),
updateLocationSwitch: (value) => dispatch(updateLocationStatus(value)),
updateIsEdit: (value) => dispatch(updateIsEdit(value)),
storeRegistrationFlagInAsync: () => dispatch(storeRegistrationFlagInAsync()),
isDeviceConnected: (value) => dispatch(isDeviceConnected(value)),
requestLocationPermissions: () => dispatch(requestLocationPermissions()),
passwordChanged: (value) => dispatch(updateIsPasswordChanged(value)),
isEditPage: (value) => dispatch(isEditPage(value)),
getDeviceName: () => dispatch(getDeviceName()),
shouldEnableLocation: (value) => dispatch(shouldEnableLocation(value)),
fetchLocationList: () => dispatch(fetchLocations()),
syncRecords: (url,userName,password,locationList,deviceId,isFromError,shouldPresentErrorMsg) => dispatch(syncFailedRecords(url,userName,password,locationList,deviceId,isFromError,shouldPresentErrorMsg)),
fetchFailedRecords: (shouldShowLoader) => dispatch(fetchFailedRecords(shouldShowLoader)),
updateDeviceAction: (action,deviceId,url) => dispatch(performDeviceAction(action,deviceId,url)),
callLogoutApi: (userName,password) => dispatch(callLogoutApi(userName,password)),
syncDeviceActions: () => dispatch(syncDeviceActions()),
syncPendingUpdates: (url,userName,password,deviceId) => dispatch(syncPendingUpdates(url,userName,password,deviceId)),
fetchPendingLocationsList: () => dispatch(fetchPendingLocationsList()),
showPasswordChangeAlert: (alertFlag,navigation) => dispatch(handleUIForPasswordChange(alertFlag,navigation)),
}
}
export default connect(mapStateToProps,mapDispatchToProps)(Profile);
Here are the reducers:
const initialState = {
url: '',
userName : '',
password : '',
deviceName : '',
resourceCode : '',
isDeviceConnected : false,
allFieldsFilled: false,
token: '',
gpsTrackingInterval : 5,
apiPostingInterval : 30,
failureMessage : '',
registered : false,
edited: false,
editPage: false,
isConnected: true,
shouldEnableLocation: false,
resourceDesc: '',
adminEmail: '',
companyName: ''
}
const profileReducer = (state=initialState,action) => {
switch (action.type) {
case actionTypes.UPDATE_URL :
return {
...state,
url: action.payload
}
...
}
This is the Redux action:
export const updateURL = (url) => {
return {
type: actionTypes.UPDATE_URL,
payload: url
};
};
Any help would be much appreciated.
import React, { Component } from 'react';
import {
StyleSheet, Text, View, TextInput, TouchableOpacity, Image,
KeyboardAvoidingView, ScrollView, SafeAreaView, Linking
} from 'react-native';
import { COLOR_BLACK, COLOR_GRAY_9, COLOR_TRANSPARENT, COLOR_GRAY_4 } from '../../../constants/colors';
import ImgProntoLogo from '../../../assets/images/pronto-logo.png';
import ImgPasswordVisibleIcon from '../../../assets/images/visibility.png';
import ImgUrl from '../../../assets/images/url.png';
import ImgBarcode from '../../../assets/images/scan-barcode.png';
import ImgUsernameIcon from '../../../assets/images/username.png';
import ImgPasswordIcon from '../../../assets/images/password.png';
import ImgPasswordHide from '../../../assets/images/password-hide.png';
import GlobalStyleSheet from '../../../constants/styles';
import {
PASSWORD, USERNAME, URL_CONNECT
} from '../../../constants/strings';
import { StackActions, NavigationActions } from 'react-navigation';
import Sync from '../../../utils/Syncing';
import { AsyncStorage } from 'react-native';
export default class Configuration extends Component {
constructor(props) {
super(props)
this.handleOpenURL = this.handleOpenURL.bind(this);
this.handleScanPress = this.handleScanPress.bind(this);
}
async componentWillMount() {
this.props.clearConfiguration();
this.props.checkConnectivity();
Linking.addEventListener('url', this.handleOpenURL);
Sync.removeDataFromUserTable();
Sync.removeDataFromCompanyTable();
}
componentDidMount() {
console.log("COMPONENT MOUNTING");
Linking.getInitialURL().then((url) => {
if (url) {
url = url.substring(18);
this.props.updateURL(url);
}
}).catch(err => console.error('An error occurred', err))
}
componentWillReceiveProps(props) {
console.log("WILL RECEIVE")
}
handleOpenURL = (event) => {
this.props.updateURL(event.url.substring(18))
}
copyRights() {
var currentYear = new Date().getFullYear().toString();
return '© '.concat(currentYear).concat(' Pronto Software Limited.All Rights Reserved.');
}
// Connect the device to the pronto connect
async connectDevice() {
this.props.showLoader();
this.props.resetConnectPasswordVisibility();
await this.props.connectDevice(this.props.configuration.url,
this.props.configuration.username, this.props.configuration.password);
let isDeviceConnected = await AsyncStorage.getItem("isConnected");
if (isDeviceConnected === "true") {
const resetAction = StackActions.reset({
index: 0,
actions: [NavigationActions.navigate({ routeName: 'Register' })],
});
this.props.navigation.dispatch(resetAction);
}
this.props.hideLoader();
}
static navigationOptions = {
header: null
}
handleScanPress() {
const action = StackActions.reset({
index: 0,
actions: [NavigationActions.navigate({ routeName: 'Scanner' })],
});
this.props.navigation.push('Scanner');
}
render() {
return (
<SafeAreaView style={GlobalStyleSheet.container}>
<KeyboardAvoidingView style={GlobalStyleSheet.container} >
<View style={styles.headerLogoView}>
<Image source={ImgProntoLogo} style={styles.logo} />
</View>
<ScrollView keyboardShouldPersistTaps="handled" style={styles.scrollViewStyle}>
<View style={{ flex: 1, height: '100%' }}>
<View style={styles.viewContainer}>
<Text style={[GlobalStyleSheet.textHeading4, GlobalStyleSheet.marginTop10,
GlobalStyleSheet.marginBottom10]}>CONFIGURE DEVICE</Text>
<View style={[GlobalStyleSheet.textInputView, GlobalStyleSheet.marginBottom10]}>
<Image style={GlobalStyleSheet.iconInputBar} source={ImgUrl} />
<TextInput
underlineColorAndroid={COLOR_TRANSPARENT}
style={GlobalStyleSheet.textInput}
autoCapitalize='none'
placeholder={URL_CONNECT}
value={this.props.configuration.url}
onChangeText={(value) => { this.props.updateURL(value) }}
editable={!(this.props.configuration.isDeviceConnected)}
/>
<TouchableOpacity style={[GlobalStyleSheet.passwordTouchable]} onPress={this.handleScanPress}>
<Image style={[GlobalStyleSheet.passwordShowHideIcon]} source={ImgBarcode} />
</TouchableOpacity>
</View>
<View style={[GlobalStyleSheet.textInputView, GlobalStyleSheet.marginBottom10]}>
<Image style={GlobalStyleSheet.iconInputBar} source={ImgUsernameIcon} />
<View style={[GlobalStyleSheet.flexRow, { flex: 1 }]}>
<TextInput
placeholder={USERNAME}
underlineColorAndroid={COLOR_TRANSPARENT}
style={GlobalStyleSheet.textInput}
onChangeText={(value) => { this.props.updateUsername(value) }}
editable={!(this.props.configuration.isDeviceConnected)}
/>
</View>
</View>
<View style={[GlobalStyleSheet.textInputView, GlobalStyleSheet.marginBottom10]} >
<Image style={[GlobalStyleSheet.iconInputBar]} source={ImgPasswordIcon} />
<View style={[GlobalStyleSheet.flexRow, { flex: 1 }]}>
<TextInput
placeholder={PASSWORD}
underlineColorAndroid={COLOR_TRANSPARENT}
contextMenuHidden={true}
style={GlobalStyleSheet.textInput}
autoCapitalize='none'
onChangeText={(value) => { this.props.updatePassword(value) }}
editable={!(this.props.configuration.isDeviceConnected)}
secureTextEntry={!(this.props.configuration.passwordVisibility)} />
<TouchableOpacity style={[GlobalStyleSheet.passwordTouchable]}
onPress={() => {
if (!this.props.configuration.isDeviceConnected) {
this.props.togglePasswordVisibility(this.props.configuration.passwordVisibility)
}
}}>
{
this.props.configuration.passwordVisibility ?
(<Image style={[GlobalStyleSheet.passwordShowHideIcon]} source={ImgPasswordVisibleIcon} />) :
(<Image style={[GlobalStyleSheet.passwordShowHideIcon]} source={ImgPasswordHide} />)
}
</TouchableOpacity>
</View>
</View>
{
this.props.configuration.isDeviceConnected ?
(
<TouchableOpacity style={GlobalStyleSheet.touchableBarProcessed} disabled={true} >
<Text style={GlobalStyleSheet.textTouchableBarProcessed}>CONNECTED</Text>
</TouchableOpacity>
) :
(this.props.configuration.url != "" &&
this.props.configuration.username != "" && this.props.configuration.password != "" ?
(
<TouchableOpacity style={[GlobalStyleSheet.touchableBarEnabled]}
onPress={async () => { await this.connectDevice() }}>
<Text style={GlobalStyleSheet.textTouchableBarEnabled}>CONNECT</Text>
</TouchableOpacity>
) :
(
<TouchableOpacity style={[GlobalStyleSheet.touchableBarDisabled]} disabled={true}>
<Text style={[GlobalStyleSheet.textTouchableBarDisabled]}>CONNECT</Text>
</TouchableOpacity>
)
)
}
</View>
</View>
<View style={styles.copyRightsView}>
<Text style={GlobalStyleSheet.copyRightsText}>{this.copyRights()}</Text>
</View>
</ScrollView>
</KeyboardAvoidingView >
</SafeAreaView >
);
}
}
const styles = StyleSheet.create({
container: {
flex: 1,
height: '100%',
width: '100%',
backgroundColor: COLOR_GRAY_9,
},
headerLogoView: {
height: 50,
backgroundColor: COLOR_GRAY_9,
elevation: 5,
justifyContent: 'center',
alignItems: 'center',
marginBottom: 2,
shadowOffset: { width: 2, height: 2, },
shadowColor: COLOR_BLACK,
shadowOpacity: 0.1,
},
logo: {
height: 40,
width: '80%',
resizeMode: 'contain',
},
viewContainer: {
marginLeft: 15,
marginRight: 15,
paddingBottom: 10
},
copyRightsView: {
alignItems: 'center',
minHeight: 40,
paddingBottom: 5,
},
scrollViewStyle: {
flex: 1,
height: '100%',
paddingTop: 10
},
});

JSON data in not coming on FlstList in react native

I know how to populate jSON data on FlatList and I have done that , but now here , I am populating data in between button and table data , In componentDidMount i am calling both function , first table create and then JSON call , Table data I am taking from QRCode scan from another screen and taking here .
import React, { Component } from 'react';
import { StyleSheet, View, ActivityIndicator, ScrollView } from 'react-native';
import { Table, Row, Rows } from 'react-native-table-component';
import {Button, Text, DatePicker, Item, Picker, Input,
Textarea,FlatList} from 'native-base';
export default class OpenApplianceIssue extends Component {
constructor(props) {
super(props);
this.state = {
// tableHead: ['Head', 'Head2', 'Head3', 'Head4'],
tableData: [], qrData: '', loading: false, selectedPriority: '',
selectedIssue: '', selectedReason: '', selectedTriedRestart: '',
selectedPowerLED: '', selectedBurning: '', selectedNoise: '',
AbcSdata : null, loading : true,
}
this.setDate = this.setDate.bind(this);
}
setDate(newDate) {
}
_loadInitialState = async () => {
const { navigation } = this.props;
const qdata = navigation.getParam('data', 'NA').split(',');
var len = qdata.length;
const tData = [];
console.log(len);
for(let i=0; i<len; i++)
{
var data = qdata[i].split(':');
const entry = []
entry.push(`${data[0]}`);
entry.push(`${data[1]}`);
tData.push(entry);
}
this.setState({tableData: tData } );
console.log(this.state.tableData);
this.setState({loading: true});
}
componentDidMount() {
this._loadInitialState().done();
// this.createViewGroup();
}
// componentDidMount() {
// this.createViewGroup();
// }
createViewGroup = async () => {
try {
const response = await fetch(
'http://Dsenze/userapi/sensor/viewsensor',
{
method: 'POST',
headers: {
Accept: 'application/json',
'Content-Type': 'application/json',
},
body: JSON.stringify({
"password": 'admin',
"username": 'admin',
"startlimit":"0",
"valuelimit":"10",
}),
}
);
const responseJson = await response.json();
const { sensorData } = responseJson;
this.setState({
AbcSdata: sensorData,
loading: false,
});
} catch (e) {
console.error(e);
}
};
updateSearch = search => {
this.setState({ search });
};
keyExtractor = ({ id }) => id.toString();
keyExtractor = ({ inventory }) => inventory.toString();
renderItem = ({ item }) => (
<TouchableOpacity
style={styles.item}
activeOpacity={0.4}
onPress={() => {
this.clickedItemText(item);
}}>
<Text style={styles.buttonText}>Id {item.inventory}</Text>
<Text>Inv {item.inventory}</Text>
<Text>Sensor {item.inventory}</Text>
</TouchableOpacity>
);
onClickListener = (viewId) => {
if(viewId == 'tag')
{
this.props.navigation.navigate('AddSensors');
}}
render() {
const state = this.state;
const AbcSdata = this.state;
if(this.state.loading == false) {
return ( <ActivityIndicator size='large' style={{height:80}} /> )
}
else {
return (
<ScrollView style={styles.container}>
<Button full rounded light style={{backgroundColor: 'blue', justifyContent: 'center', alignItems: 'center'}}
onPress={() => this.onClickListener('tag')}>
<Text style={{color: 'white'}}>Add Sensors</Text>
</Button>
<View style={styles.container1}>
{this.state.loading ? (
<ActivityIndicator size="large" />
) :
(
<FlatList
AbcSdata={AbcSdata}
renderItem={this.renderItem}
keyExtractor={this.keyExtractor}
/>
)}
</View>
<View>
<Text
style={{alignSelf: 'center', fontWeight: 'bold', color: 'black'}} >
Inventory Details
</Text>
<Table borderStyle={{borderWidth: 2, borderColor: '#c8e1ff', padding:10,paddingBottom: 10}}>
<Rows data={state.tableData} textStyle={styles.text}/>
</Table>
</View>
</ScrollView>
)
}
}
}
const styles = StyleSheet.create({
container: { flex: 1, padding: 16, paddingTop: 30, backgroundColor: '#fff' },
head: { height: 40, backgroundColor: '#f1f8ff' },
text: { margin: 6 }
});

try this code ..
import React, { Component } from 'react';
import { View, Text, TextInput,
FooterTab,Button,TouchableOpacity, ScrollView, StyleSheet,
ActivityIndicator ,Header,FlatList} from 'react-native';
import {Icon} from 'native-base';
import { Table, Row, Rows } from 'react-native-table-component';
import { createStackNavigator } from 'react-navigation';
import { SearchBar } from 'react-native-elements';
export default class OpenApplianceIssue extends Component {
constructor() {
super();
this.state = {
AbcSdata: null,
loading: true,
search: '',
tableData: [], qrData: '', selectedPriority: '',
selectedIssue: '', selectedReason: '', selectedTriedRestart: '',
selectedPowerLED: '', selectedBurning: '', selectedNoise: '',
};
this.setDate = this.setDate.bind(this);
}
setDate(newDate) {
}
_loadInitialState = async () => {
const { navigation } = this.props;
const qdata = navigation.getParam('data', 'NA').split(',');
var len = qdata.length;
const tData = [];
console.log(len);
for(let i=0; i<len; i++)
{
var data = qdata[i].split(':');
const entry = []
entry.push(`${data[0]}`);
entry.push(`${data[1]}`);
tData.push(entry);
}
this.setState({tableData: tData } );
console.log(this.state.tableData);
this.setState({loading: true});
}
componentDidMount() {
this._loadInitialState().done();
this.createViewGroup();
}
createViewGroup = async () => {
try {
const response = await fetch(
'http:Dsenze/userapi/sensor/viewsensor',
{
method: 'POST',
headers: {
Accept: 'application/json',
'Content-Type': 'application/json',
},
body: JSON.stringify({
"password": 'admin',
"username": 'admin',
"startlimit":"0",
"valuelimit":"10",
}),
}
);
const responseJson = await response.json();
const { sensorData } = responseJson;
this.setState({
AbcSdata: sensorData,
loading: false,
});
} catch (e) {
console.error(e);
}
};
updateSearch = search => {
this.setState({ search });
};
keyExtractor = ({ id }) => id.toString();
keyExtractor = ({ inventory }) => inventory.toString();
renderItem = ({ item }) => (
<TouchableOpacity
style={styles.item}
activeOpacity={0.4}
onPress={() => {
this.clickedItemText(item);
}}>
<Text style={styles.buttonText}>Id {item.id}</Text>
<Text>Hospital Name {item.inventory}</Text>
<Text>User {item.inventory}</Text>
<Text>Date {item.inventory}</Text>
</TouchableOpacity>
);
onClickListener = (viewId) => {
if(viewId == 'tag')
{
this.props.navigation.navigate('AddSensors');
}}
renderSeparator = () => {
return (
<View
style={{
height: 1,
width: "86%",
backgroundColor: "#CED0CE",
}}
/>
);
};
render() {
const { loading, AbcSdata } = this.state;
const state = this.state;
return (
<ScrollView>
<View style={styles.container1}>
<TouchableOpacity full rounded light style={{backgroundColor: 'blue', justifyContent: 'center', alignItems: 'center'}}
onPress={() => this.onClickListener('tag')}>
<Text style={{color: 'white'}}>Add Sensors</Text>
</TouchableOpacity>
</View>
<View style={styles.container1}>
{this.state.loading ? (
<ActivityIndicator size="large" />
) :
(
<FlatList
data={AbcSdata}
renderItem={this.renderItem}
keyExtractor={this.keyExtractor}
ItemSeparatorComponent={this.renderSeparator}
/>
)}
</View>
<View>
<Text
style={{alignSelf: 'center', fontWeight: 'bold', color: 'black'}} >
Inventory Details
</Text>
<Table borderStyle={{borderWidth: 2, borderColor: '#c8e1ff', padding:10,paddingBottom: 10}}>
<Rows data={state.tableData} textStyle={styles.text}/>
</Table>
</View>
</ScrollView>
);
}
}
const styles = StyleSheet.create(
{
container1:
{
flex: 1,
alignItems: 'stretch',
fontFamily: "vincHand",
color: 'blue'
},
header_footer_style:{
width: '100%',
height: 44,
backgroundColor: '#4169E1',
alignItems: 'center',
justifyContent: 'center',
color:'#ffffff',
},
Progressbar:{
justifyContent: 'center',
alignItems: 'center',
color: 'blue',
},
ListContainer :{
borderColor: '#48BBEC',
backgroundColor: '#000000',
color:'red',
alignSelf: 'stretch' ,
},
container2:
{
flex: 1,
justifyContent: 'center',
alignItems: 'stretch',
paddingHorizontal: 15
},
inputBox:{
width:300,
borderColor: '#48BBEC',
backgroundColor: '#F8F8FF',
borderRadius:25,
paddingHorizontal:16,
fontSize:16,
color:'#000000',
marginVertical:10,
},
button:{
width:300,
backgroundColor:'#4169E1',
borderRadius:25,
marginVertical:10,
paddingVertical:16
},
buttonText:{
fontSize:16,
fontWeight:'500',
color:'#ffffff',
textAlign:'center'
},
textStyle:{
fontSize:16,
fontWeight:'500',
color:'#ffffff',
textAlign:'center'
},
item:
{
padding: 15
},
text:
{
fontSize: 18
},
button:{
width:300,
backgroundColor:'#4169E1',
borderRadius:25,
marginVertical:10,
paddingVertical:16
},
buttonText:{
fontSize:16,
fontWeight:'500',
color:'red',
textAlign:'center'
},
separator:
{
height: 2,
backgroundColor: 'rgba(0,0,0,0.5)'
},
container: { flex: 1, padding: 16, paddingTop: 30, backgroundColor: '#fff' },
head: { height: 40, backgroundColor: '#f1f8ff' },
text: { margin: 6 }
});

In your FlatList component you are setting AbcSdata={AbcSdata}, while you should be setting the data prop:
<FlatList
data={AbcSdata}
renderItem={this.renderItem}
keyExtractor={this.keyExtractor}
/>

It could be because _loadInitialState in your componentDidMount is an async call and table is getting rendered initially with no data. You could try passing in some prop to refresh once you have data. Also, in the code you put here, all calls to createViewGroup() are commented out but the definition is still there. Not a big problem but still very confusing for someone looking into your code.

undefined is not an object (evaluating 'this.props.navigation")

My navigation suddenly broke down. So there are 3 screens/components, I am using react-navigation to navigate between them. First screen is to enter mobile phone number and password, it is sent to api, and some data is saved into state and passed to second screen, where i am enter code from sms and send another request to api, if response.status == 200, it goes to third screen. Navigation from 1st screen to 2nd works, but from 2nd to third is not. Error occurs when i am going to third screen.
FirstPage.js
export default class FirstPage extends React.Component {
constructor(props) {
super(props);
this.state = {
text: '',
password: '',
password2: ''
}
}
state = {
uuid: null
}
getCode(text, psw) {
fetch('url', {
method: 'POST',
headers: {
Accept: 'application/json',
'Content-Type': 'application/json'
},
body: JSON.stringify({"telephone": text, "password": psw})
})
.then(response => response.json())
.then(response => {
let uuid = response['data']['id'];
this.setState({uuid});
this
.props
.navigation
.navigate('SecondPage', {uuid});
})
};
render() {
return (
<View
style={{
flex: 1,
justifyContent: "center",
alignItems: "center"
}}>
<TouchableWithoutFeedback onPress={Keyboard.dismiss} accessible={false}>
<View
style={{
width: 200,
height: 60,
borderColor: 'gray',
borderWidth: 1,
justifyContent: "center",
alignItems: "center"
}}>
<View>
<Text>phone number
</Text>
</View>
<View>
<TextInput
keyboardType='phone-pad'
onChangeText={(text) => this.setState({text})}
value={this.state.text}
placeholder={"phone number"}/>
</View>
</View>
</TouchableWithoutFeedback>
<TouchableWithoutFeedback onPress={Keyboard.dismiss} accessible={false}>
<View
style={{
width: 200,
height: 60,
marginTop: 25,
borderColor: 'gray',
borderWidth: 1,
justifyContent: "center",
alignItems: "center"
}}>
<View>
<Text>password</Text>
</View>
<View>
<TextInput
keyboardType='phone-pad'
secureTextEntry
onChangeText={(password) => this.setState({password})}
value={this.state.password}
placeholder={"password"}/>
</View>
</View>
</TouchableWithoutFeedback>
<TouchableWithoutFeedback onPress={Keyboard.dismiss} accessible={false}>
<View
style={{
width: 200,
height: 60,
marginTop: 25,
borderColor: 'gray',
borderWidth: 1,
justifyContent: "center",
alignItems: "center"
}}>
<Text>password2</Text>
<TextInput
keyboardType='phone-pad'
secureTextEntry
onChangeText={(password2) => this.setState({password2})}
value={this.state.password2}
placeholder={"password2"}/>
</View>
</TouchableWithoutFeedback>
<Button
title="getcode"
onPress={() => this.getCode(this.state.text, this.state.password)}/>
</View>
);
}
}
SecondPage.js
export default class SecondPage extends React.Component {
input = React.createRef();
constructor(props) {
super(props);
this.state = {
value: "",
focused: false,
uuid: this.props.navigation.state.params.uuid,
};
}
state = {
codeConf: '',
}
sendCode(uid, code) {
const body = new FormData
body.append("authentication", uid)
body.append("code", code)
fetch('url', {
method: 'POST',
body,
headers: {
Token: "2f30743e-014d-4f0f-8707-73ae550d8f14"
}
}).then(function (response) {
console.log(uid + "code is " + code)
console.log(response);
if (response.ok) {
this.props.navigation.navigate('ThirdPage');
} else {
console.log(response.status)
}
})
.catch((error) => {
console.error(error);
});
}
render() {
return (
<View
style={{
flex: 1,
backgroundColor: '#FDD7E4',
alignSelf: 'stretch',
textAlign: 'center',
borderWidth: 1,
justifyContent: "center",
alignItems: "center"
}}>
<CodeInput
ref="codeInputRef2"
secureTextEntry
codeLength={6}
keyboardType='phone-pad'
activeColor='rgba(0, 0, 0, 1)'
inactiveColor='rgba(0, 0, 0 , 0.1)'
autoFocus={true}
ignoreCase={true}
inputPosition='center'
size={50}
onFulfill={(code) => {
this.setState({codeConf: code})
}}/>
<Button
title="send code"
onPress={this.sendCode(this.state.uuid, this.state.codeConf)} />
</View>
)
}
}
ThirdPage.js
export default class ThirdPage extends React.Component {
render() {
return (
<View style={styles}>
<Text>
Hi there
</Text>
</View>
)
}
}
And finally App.js
class App extends React.Component {
render() {
return (<AppStackNavigator />)
}
}
const AppStackNavigator = createStackNavigator({
FirstPage: {
screen: FirstPage
},
SecondPage: {
screen: SecondPage
},
ThirdPage: {
screen: ThirdPage
}
}, {initialRouteName: 'FirstPage'})
export default createAppContainer(AppStackNavigator);
I don't really why it happens, because react-navigation says that all then screens from App.js is sent to every screen as this.props.navigation, so I can access them from anywhere.

The issue is because you have lost scope by not binding your functions, this means that you are no longer accessing the correct value of this. You can fix this issue by using arrow functions.
Rewrite your sendCode function in the following way, noticing the use of arrow functions
sendCode = (uid, code) => { // <- arrow function
const body = new FormData();
body.append('authentication', uid);
body.append('code', code);
fetch('url', {
method: 'POST',
body,
headers: {
Token: '2f30743e-014d-4f0f-8707-73ae550d8f14'
}
}).then(response => { // <- arrow function
console.log(uid + 'code is ' + code);
console.log(response);
if (response.ok) {
this.props.navigation.navigate('ThirdPage');
} else {
console.log(response.status);
}
}).catch((error) => {
console.error(error);
});
}
And finally update the code in your button to be.
<Button
title="send code"
onPress={() => this.sendCode(this.state.uuid, this.state.codeConf)} />

you need to bind and pass function definition to onPress prop of Button component in SecondPage.js.
<Button
title="send code"
onPress={()=>this.sendCode(this.state.uuid,this.state.codeConf)} />

I Tried to fetch Json data to my picker List but its not working in react native

<--it shows data.source error-->
import React, { Component } from "react";
import { AppRegistry, StyleSheet, View, Platform, Picker, ActivityIndicator, Button, Alert} from "react-native";
export default class Project extends Component {
constructor(props)
{
super(props);
this.state = {
isLoading: true,
PickerValueHolder : ""
}; }
componentDidMount() {
return fetch("https://facebook.github.io/react-native/movies.json")
.then((response) => response.json())
.then((responseJson) => {
this.setState({
isLoading: false,
dataSource: responseJson
}, function() {
// In this block you can do something with new state.
});
})
.catch((error) => {
console.error(error);
});}
GetPickerSelectedItemValue=()=>{
Alert.alert(this.state.PickerValueHolder);
}
render() {
if (this.state.isLoading) {
return (
<View style={{flex: 1, paddingTop: 20}}>
<ActivityIndicator />
</View>`help needed`
);
}
return (
<View style={styles.MainContainer}>
<Picker
selectedValue={this.state.PickerValueHolder}
onValueChange={(itemValue, itemIndex) => this.setState({PickerValueHolder: itemValue})} >
{ this.state.dataSource.map((item, key)=>(
<Picker.Item label={item.title} value={item.title} key={key} />)
)}
</Picker>
<Button title="Click Here To Get Picker Selected Item Value" onPress={ this.GetPickerSelectedItemValue } />
</View>
);}}
const styles = StyleSheet.create({
MainContainer :{
justifyContent: "center",
flex:1,
margin: 10
}});

import React, { Component } from "react";
import { ListView, Text, StyleSheet, View, ActivityIndicator, Button, Alert} from "react-native";
export default class Project extends Component {
constructor(props)
{
super(props);
this.state = {
isLoading: true,
PickerValueHolder : "",
language: ''
};
}
GetPickerSelectedItemValue(value: string) {
Alert.alert(value);
this.setState({
selected: value
});
}
GetItem (title) {
Alert.alert(title);
}
componentDidMount() {
return fetch('https://facebook.github.io/react-native/movies.json')
.then((response) => response.json())
.then((responseJson) => {
let ds = new ListView.DataSource({rowHasChanged: (r1, r2) => r1 !== r2});
this.setState({
isLoading: false,
dataSource: ds.cloneWithRows(responseJson['movies']),
}, function() {
// In this block you can do something with new state.
});
})
.catch((error) => {
console.error(error);
});
}
ListViewItemSeparator = () => {
return (
<View
style={{
height: .5,
width: "100%",
backgroundColor: "#000",
}}
/>
);
}
render() {
if (this.state.isLoading) {
return (
<View style={{flex: 1, paddingTop: 20}}>
<ActivityIndicator />
</View>
);
}
return (
<View style={styles.MainContainer}>
<ListView
dataSource={this.state.dataSource}
renderSeparator= {this.ListViewItemSeparator}
renderRow={(rowData) =>
<View style={{flex:1, flexDirection: 'row'}}>
<Text onPress={this.GetItem.bind(this, rowData.title)} style={styles.textViewContainer} >{rowData.title}</Text>
</View>
}
/>
</View>
);
}
}
const styles = StyleSheet.create({
MainContainer :{
justifyContent: "center",
flex:1,
margin: 10
}
});