Getting "Warning may not respond to a" message iphone

I am calling a method from another method and keep getting a warning: firstViewController may not respond to '-playJS'

-(void) playJS
{

//my code here开发者_如何学运维

}

You probably haven't declared the method yet in the header file.

Instead of writing the declaration in the header file, it's also OK to declare it before the call.

If the methods are in different classes (and files) you need to import the headerfile too.