javascript - If/else statements in React Native -


i have problem if/else statements in react native.

for example, have 2 states:

onopen() {   this.setstate({     index: 1   }); }  onclose() {   this.setstate({     index: 0   }); }

i need set state index: 0, when toggle close , index: 1, when toggle open.

<touchableopacity onpress={() =>    {index === 0      ? navigator.toggledrawer(this.onclose())      : navigator.toggledrawer(this.onopen())   } }>

for now, when click on menu-button receive index 0 every time, should change on 1 , back. thanks.

component:

import react 'react'; import {   touchableopacity,   image  } 'react-native';  export default class home extends component {   constructor(props) {     super(props);     this.state = {       index: 0     };   }   onopen() {     this.setstate({       index: 1     });   }    onclose() {     this.setstate({       index: 0     });   }    render() {     const { index } = this.state;     return (    <touchableopacity onpress={() => {index === 1 ?       navigator.toggledrawer(this.onclose()) :       navigator.toggledrawer(this.onopen())}}>         <image         source={require('something.png')}        />        </touchableopacity>     );   } }

enter image description here

export default class home extends component {   constructor(props) {     super(props);     this.state = { index: 0 };     this.toggleindex = this.toggleindex.bind(this);   }    toggleindex() {     navigator.toggledrawer();     this.setstate({ index: this.state.index === 0 ? 1 : 0 });   }    render() {     return (       <touchableopacity onpress={toggleindex}>         <image           source={require('something.png')}         />       </touchableopacity>     );   } }

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