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use crate::{Overlay, Widget};
use glib::object::Cast;
use glib::signal::{connect_raw, SignalHandlerId};
use glib::translate::*;
use glib::ObjectType;
use std::mem::transmute;
use std::ptr;
impl Overlay {
pub fn connect_get_child_position<F>(&self, f: F) -> SignalHandlerId
where
F: Fn(&Self, &Widget) -> Option<gdk::Rectangle> + 'static,
{
unsafe {
let f: Box<F> = Box::new(f);
connect_raw(
self.as_ptr() as *mut _,
b"get-child-position\0".as_ptr() as *mut _,
Some(transmute(get_child_position_trampoline::<F> as usize)),
Box::into_raw(f),
)
}
}
}
unsafe extern "C" fn get_child_position_trampoline<
F: Fn(&Overlay, &Widget) -> Option<gdk::Rectangle> + 'static,
>(
this: *mut ffi::GtkOverlay,
widget: *mut ffi::GtkWidget,
allocation: *mut gdk::ffi::GdkRectangle,
f: glib::ffi::gpointer,
) -> glib::ffi::gboolean {
let f: &F = &*(f as *const F);
match f(
Overlay::from_glib_borrow(this).unsafe_cast_ref(),
&from_glib_borrow(widget),
) {
Some(rect) => {
ptr::write(allocation, ptr::read(rect.to_glib_none().0));
true
}
None => false,
}
.into_glib()
}