Compiler warning about "Semantic Issue" -- how to fix?

I receive this warning when building my app:

warning: Semantic Issue: Local declaration of 'datePicker开发者_如何学运维' hides instance variable

What does this mean and how do I fix it?

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You probably have a method with parameter named datePicker. This method is located in a class which has a field with the same name.

You need to change a name of one of these variables to get rid of this warning.

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rename your ivars like this:

@interface SomeClass{
  NSString * _datePicker;
}
@property (nonatomic,retain) NSString * datePicker;
@end

@implementation SomeClass

@synthesize datePicker =_datePicker;

...