I'm using React-Native and "Formik" to try to create a text input field. I define a constant input field as the following: and then try to embed it in a container using the following function: The onChangeText line is what's causing the error; when I get rid of "username" the error disappears, but I need to call handleChange with that argument. (Additionally, whenever I try to call anything on the values parameter, it gives me the error that it is undefined).

Any advice?

CodePudding user response：

So the longer answer is that onChangeText is requiring a callback function, (exactly like onClick for instance)

So basically you have to pass {handleChange} and not {handleChange()} or it will call your function each time it rerenders

You issue is that you had a parameter, in that case you can define an arrow function directly here like I told you in the comments and this arrow function will contain a call to your function with your parameter:

onChangeText={() => {handleChange("username")}}