On Picker Value change call function or array in r

2019-08-02 21:31发布

问题:

Here what am trying to do is , on Picker value change calling the function and trying to call for loop and draw 5 TextInput , but getting error . Please help for this small mistake , when i am trying to call myloop array directly on value change its generating error that array can't be call as function .

import * as React from 'react';
import { Text, View, StyleSheet, Alert, Picker } from 'react-native';
import { Constants } from 'react-native';
import { TextInput } from 'react-native-gesture-handler';

var myloop = [];
;
export default class UiDynamic extends React.Component {

  // add a selectValue to your state to stop the overwriting
  state = {
    PickerValueHolder: [],
    selectedValue: ''
  }

  componentDidMount() {
    // remove the return 
   fetch('http:///Dsenze/userapi/inventory/viewinventorytype', {  
        method: 'POST',
        headers: {
          'Accept': 'application/json',
          'Content-Type': 'application/json',
        },
        body: JSON.stringify({
          "username" :"admin",
          "password" :"admin"
        })
      }).then((response) => response.json())
      .then((responseJson) => {
        // use the inventoryTypeData as it is already an array
       let PickerValueHolder = responseJson.inventoryTypeData;
        console.log("Array data" , PickerValueHolder)

        this.setState({ PickerValueHolder }); // Set the new state
      })
      .catch((error) => {
        console.error(error);
      });
    }

onPickerValueChange=()=>{

    {myloop}
    console.log("Picker change" , myloop);
    //  this.onPickerValueTextinput();

    }

  render() {

        for (let i = 0; i < 5; i++) {

            myloop.push(
              <View key={<TextInput></TextInput>}>
              <TextInput style={{ textAlign: 'center', marginTop: 5 }} 
              placeholder="Enter your name ">
              </TextInput>
              </View>
            )
            }


    return (
      <View style={styles.container}>

      {/* {myloop} */}

        {<Picker
                selectedValue={this.state.selectedValue}
               onValueChange={this.onPickerValueChange}>
                { this.state.PickerValueHolder.map((item, key)=>
                  <Picker.Item label={item.name} value={item.name} key={key} />
                )}
              </Picker>}
      </View>
    );
  }
}

const styles = StyleSheet.create({
  container: {
    flex: 1,
    justifyContent: 'center',
    backgroundColor: '#ecf0f1',
    padding: 8,
  }
});

Thanks