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Call setValue:forKey: and use key _parentViewController with the viewController:

<pre style="background: none repeat scroll 0% 0% rgb(240, 240, 240); border: 1px dashed rgb(204, 204, 204); color: black; font-family: arial; font-size: 12px; height: auto; line-height: 20px; overflow: auto; padding: 0px; text-align: left; width: 99%;"> - (void)setParentController:(UIViewController*)parent{
[self setValue:parent forKey:@"_parentViewController"];
}
</pre>
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