relm4/
loading_widgets.rs

1//! Utilities for removing temporary widgets from
2//! async factories or components.
3
4use crate::RelmRemoveExt;
5
6trait RemoveTempChild {
7    fn remove(&mut self);
8}
9
10struct TempWidgetsInner<C: RelmRemoveExt> {
11    container: C,
12    children: Vec<C::Child>,
13}
14
15impl<C: RelmRemoveExt> RemoveTempChild for TempWidgetsInner<C>
16where
17    C::Child: AsRef<C::Child>,
18{
19    fn remove(&mut self) {
20        for child in &mut self.children {
21            self.container.container_remove(&child);
22        }
23    }
24}
25
26/// A type that stores widget containers and their child
27/// widgets and removes all children automatically when dropped.
28///
29/// This mechanism is used by async components and factories
30/// to show widgets while the async init function isn't completed.
31/// Once the actual widgets are initialized, the temporary loading
32/// widgets can be removed again, which is simply done with this type.
33pub struct LoadingWidgets {
34    containers: Vec<Box<dyn RemoveTempChild>>,
35}
36
37impl std::fmt::Debug for LoadingWidgets {
38    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
39        f.debug_struct("LoadingWidgets")
40            .field("containers", &self.containers.len())
41            .finish()
42    }
43}
44
45impl Drop for LoadingWidgets {
46    fn drop(&mut self) {
47        for child in &mut self.containers {
48            child.remove();
49        }
50    }
51}
52
53impl LoadingWidgets {
54    fn temp_child<C, W>(container: C, children: &[W]) -> Box<dyn RemoveTempChild>
55    where
56        C: RelmRemoveExt + 'static,
57        W: AsRef<C::Child>,
58        C::Child: Clone + AsRef<C::Child>,
59    {
60        let children = children.iter().map(|c| c.as_ref().clone()).collect();
61        let temp_child: TempWidgetsInner<C> = TempWidgetsInner {
62            container,
63            children,
64        };
65
66        Box::new(temp_child)
67    }
68
69    /// Create new [`LoadingWidgets`] with one child.
70    pub fn new<C, W>(container: C, child: W) -> Self
71    where
72        C: RelmRemoveExt + 'static,
73        W: AsRef<C::Child>,
74        C::Child: Clone + AsRef<C::Child>,
75    {
76        Self::with_children(container, &[child])
77    }
78
79    /// Create new [`LoadingWidgets`] with multiple children.
80    pub fn with_children<C, W>(container: C, children: &[W]) -> Self
81    where
82        C: RelmRemoveExt + 'static,
83        W: AsRef<C::Child>,
84        C::Child: Clone + AsRef<C::Child>,
85    {
86        let temp_child = Self::temp_child(container, children);
87        Self {
88            containers: vec![temp_child],
89        }
90    }
91
92    /// Add another child to the temporary loading widgets.
93    pub fn push<C, W>(&mut self, container: C, child: W)
94    where
95        C: RelmRemoveExt + 'static,
96        W: AsRef<C::Child>,
97        C::Child: Clone + AsRef<C::Child>,
98    {
99        let temp_child = Self::temp_child(container, &[child]);
100        self.containers.push(temp_child);
101    }
102
103    /// Add many children to the temporary loading widgets.
104    pub fn add_many<C, W>(&mut self, container: C, children: &[W])
105    where
106        C: RelmRemoveExt + 'static,
107        W: AsRef<C::Child>,
108        C::Child: Clone + AsRef<C::Child>,
109    {
110        let temp_child = Self::temp_child(container, children);
111        self.containers.push(temp_child);
112    }
113}
relm4/loading_widgets.rs

relm4/
loading_widgets.rs
