Problems with borrowing Traits
crosspostato da: https://lemmy.world/post/1916287
Hi everybody, I'm new to Rust.
So, I have a struct
Panelwhich contains a datawidgetwhich implements the traitWidgetI have to implement a function forPanelthat uses another function that requires a type that implementsWidget.I tried
Box<T>,Rc<T>,Box<dyn Widget,&T, but nothing, always compiler errors.How can I fix this?
Use
self.widget?Maybe show some code of what you're trying to do.
Yes, obviously, but there are de-referincing/borrwowing/trait problem.
If you want to check the Trait: https://docs.rs/ratatui/latest/ratatui/widgets/trait.Widget.html
If you want to check what function do I need to run: https://docs.rs/ratatui/latest/ratatui/terminal/struct.Frame.html#method.render_widget
So the struct is something like
struct Panel<T: Widget> { data: T }(tried also with Box, Rc, &mut T and BoxI need to implement a method for Panel which simply uses the function linked above. (so just asks for a Frame, the Rect type is generated by my other function)
That function takes ownership of the Widget, there's no borrowing here. Maybe that's the problem, that you're passing a reference instead of the actual object?
So, if you have a Panel containing the Widget, the function you're calling
render_widgetin has to takeself, not&selfor&mut self.Alternatively, you can use
data: Option<T>in Panel, let the function take&mut selfand then useself.data.take()to move it out of self.I checked the code and noticed that I wrote
&selfas the parameter 🤦🏻Now everything works. Thanks man
Showing the code and the errors compiler gives to you would help a bunch.
Seems like
data: Tordata: &'a mut Tshould work for you. Your function should be acceptingmut selfor&mut self.The first problem I saw is that
Widget::rendertakesselfby value, meaning that the widget will be destroyed after being rendered once. The need to satisfy that method's type could be the cause of the other errors you're running into.