pub fn invalidate(&self) {
        if let Some(state) = self.state.upgrade() {
            state.window.queue_draw();
        }
    }
// Request invalidation of the entire window contents.
Request invalidation of the entire window contents.
Request invalidation of the entire window contents .
pub fn invalidate(&self) {
        if let Some(state) = self.state.upgrade() {
            state.window.queue_draw();
        }
    }
pub fn invalidate ( & self ) { if let Some ( state ) = self . state . upgrade ( ) { state . window . queue_draw ( ) ; } }
Request invalidation of the entire window contents.
Request invalidation of the entire window contents .
&self
&self