javascript - React: Add/Change text input base on a selected option -


i trying display new text input based on selected option. able below old value entered present no matter change new select option to.

what might better way achieve this? appreciate suggestions.

class loadcomponent extends react.component {     static proptypes = {       ......     };     static defaultprops = {      ....     };     constructor() {      super();      this.state = {        value: ""      };     }      state = {       ...      };  reset = (selected) => {        this.setstate({         selectedinputname: selected.target[selected.target.selectedindex].text,         selectedinputid: selected.target.value        }); };  maketextinput = () => {     return (         <textinput             label={this.state.selectedinputname}             placeholder={`please enter ${this.state.selectedinputname} here!`}             onblur={event => this.setstate({[this.state.selectedinputid]: event.target.value})}             showclear             value={this.state.value}         />     ); }; render() {     let newinputtext = '';     if (this.state.selectedinputid !== '') {         newinputtext = this.maketextinput();     }     return (         <select             label="what search with?"             options={this.props.searchoptions}             onchange={selected => this.reset(selected)}         />         <div classname="search margin_bottom_large">             {newinputtext}     );

maketextinput function creates new object, react's perspective it's same component because react distinguishes them looking @ type , key. make react recreate element, have change 1 of values.

this code changes type of newinputtext element each time renders (because newinputtext refers new function):

reset = (selected) => {        this.setstate({         selectedinputname: selected.target[selected.target.selectedindex].text,         selectedinputid: selected.target.value        }); };  maketextinput = () => {     return (         <textinput             label={this.state.selectedinputname}             placeholder={`please enter ${this.state.selectedinputname} here!`}             onblur={event => this.setstate({[this.state.selectedinputid]: event.target.value})}             showclear         />     ); }; render() {     let newinputtext = () => '';     if (this.state.selectedinputid !== '') {         newinputtext = () => this.maketextinput();     }     return (         <select             label="what search with?"             options={this.props.searchoptions}             onchange={selected => this.reset(selected)}         />         <div classname="search margin_bottom_large">             <newinputtext />     );

this code assigns different key textinput each time:

reset = (selected) => {        this.setstate({         selectedinputname: selected.target[selected.target.selectedindex].text,         selectedinputid: selected.target.value        }); };  maketextinput = () => {     return (         <textinput             key={math.random()}             label={this.state.selectedinputname}             placeholder={`please enter ${this.state.selectedinputname} here!`}             onblur={event => this.setstate({[this.state.selectedinputid]: event.target.value})}             showclear         />     ); }; render() {     let newinputtext = '';     if (this.state.selectedinputid !== '') {         newinputtext = this.maketextinput();     }     return (         <select             label="what search with?"             options={this.props.searchoptions}             onchange={selected => this.reset(selected)}         />         <div classname="search margin_bottom_large">             {newinputtext}     );

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