I want to call the method of the subcomponent, but I can"t find the method of the subcomponent when printing.
I want to call the method of the subcomponent, but I can"t find the method of the subcomponent when printing.
you use shouldhide on state to show different parts.
when shouldhide is true , the second half is not displayed. So you can't get this.refs.test .
also, if you want to do something related to state after calling setState , you should wait until setState is finished.
because setState is an asynchronous operation, you cannot follow the Synchronize operation on the figure. It should look like this:
this.setState({
shouldhide: true
}, () => {
console.log(this.refs.test)
}) but in fact, you can get this.refs.test only if shouldhide is false .
modify BasicEdit to the following:
BasicEdit = () => {
this.setState({
shouldhide: true
}, () => {
setTimeout(() => {
console.log(this.refs.test)
}, 500)
})
}shouldhide when you set it to false, you render the data in if, but there is no ref in if
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