Javascript React Native-useRef在RNCamera上提供空值
我第一次使用react native camera,为此我使用了功能组件。我想在点击按钮时打开相机,但使用ref不起作用。这是我的密码:Javascript React Native-useRef在RNCamera上提供空值,javascript,reactjs,react-native,react-hooks,react-native-camera,Javascript,Reactjs,React Native,React Hooks,React Native Camera,我第一次使用react native camera,为此我使用了功能组件。我想在点击按钮时打开相机,但使用ref不起作用。这是我的密码: const camContainer = () => { const cameraRef = useRef(null); useEffect(() => { console.log(cameraRef); }, [cameraRef]); const openCamera = () => { const o
const camContainer = () => {
const cameraRef = useRef(null);
useEffect(() => {
console.log(cameraRef);
}, [cameraRef]);
const openCamera = () => {
const options = {quality: 0.5, base64: true};
// cameraRef.current.takePictureAsync(options);
console.log(cameraRef);
};
return (
<TouchableOpacity onPress={() => openCamera()}>
<Text>Open Camera</Text>
{!cameraRef && (
<View>
<RNCamera ref={cameraRef} style={{flex: 1, alignItems: 'center'}} />
</View>
)}
</TouchableOpacity>
);
};
const-camContainer=()=>{
const cameraRef=useRef(null);
useffect(()=>{
console.log(cameraRef);
},[cameraRef]);
常量openCamera=()=>{
const options={quality:0.5,base64:true};
//cameraRef.current.takePictureAsync(选项);
console.log(cameraRef);
};
返回(
openCamera()}>
开放式摄像机
{!cameraRef&&(
)}
);
};
我使用
useffect
登录了cameraRef
,但是cameraRef.current
仍然为空,我不明白当时如何打开相机?在RNCamera的文档中,应该是这样的
{
this.camera=ref;
}}
/>;
// ...
snap=async()=>{
如果(这个相机){
let photo=等待这个。camera.takePictureAsync();
}
};代码>你需要参考号吗?我想搬走!cameraRef应该为您的案例展示相机。我移除了cameraRef,但使用cameraRef我无法打开相机,请帮助我@GeneSy