i_slint_compiler/passes/
repeater_component.rs

1// Copyright © SixtyFPS GmbH <info@slint.dev>
2// SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-Slint-Royalty-free-2.0 OR LicenseRef-Slint-Software-3.0
3
4/*!
5Make sure that the Repeated expression are just components without any children
6 */
7
8use crate::expression_tree::{Expression, NamedReference};
9use crate::langtype::ElementType;
10use crate::object_tree::*;
11use smol_str::SmolStr;
12use std::cell::RefCell;
13use std::rc::Rc;
14
15pub fn process_repeater_components(component: &Rc<Component>) {
16    create_repeater_components(component);
17    adjust_references(component);
18}
19
20fn create_repeater_components(component: &Rc<Component>) {
21    recurse_elem(&component.root_element, &(), &mut |elem, _| {
22        let is_listview = match &elem.borrow().repeated {
23            Some(r) => r.is_listview.clone(),
24            None => return,
25        };
26        let parent_element = Rc::downgrade(elem);
27        let mut elem = elem.borrow_mut();
28
29        if matches!(&elem.base_type, ElementType::Component(c) if c.parent_element.upgrade().is_some())
30        {
31            debug_assert!(std::rc::Weak::ptr_eq(
32                &parent_element,
33                &elem.base_type.as_component().parent_element
34            ));
35            // Already processed (can happen if a component is both used and exported root)
36            return;
37        }
38
39        let comp = Rc::new(Component {
40            root_element: Rc::new(RefCell::new(Element {
41                id: elem.id.clone(),
42                base_type: std::mem::take(&mut elem.base_type),
43                bindings: std::mem::take(&mut elem.bindings),
44                change_callbacks: std::mem::take(&mut elem.change_callbacks),
45                property_analysis: std::mem::take(&mut elem.property_analysis),
46                children: std::mem::take(&mut elem.children),
47                property_declarations: std::mem::take(&mut elem.property_declarations),
48                named_references: Default::default(),
49                repeated: None,
50                is_component_placeholder: false,
51                debug: elem.debug.clone(),
52                enclosing_component: Default::default(),
53                states: std::mem::take(&mut elem.states),
54                transitions: std::mem::take(&mut elem.transitions),
55                child_of_layout: elem.child_of_layout || is_listview.is_some(),
56                layout_info_prop: elem.layout_info_prop.take(),
57                default_fill_parent: elem.default_fill_parent,
58                accessibility_props: std::mem::take(&mut elem.accessibility_props),
59                geometry_props: elem.geometry_props.clone(),
60                is_flickable_viewport: elem.is_flickable_viewport,
61                has_popup_child: elem.has_popup_child,
62                item_index: Default::default(), // Not determined yet
63                item_index_of_first_children: Default::default(),
64                is_legacy_syntax: elem.is_legacy_syntax,
65                inline_depth: 0,
66            })),
67            parent_element,
68            ..Component::default()
69        });
70
71        if let Some(listview) = is_listview {
72            if !comp.root_element.borrow().is_binding_set("height", false) {
73                let preferred = Expression::PropertyReference(NamedReference::new(
74                    &comp.root_element,
75                    SmolStr::new_static("preferred-height"),
76                ));
77                comp.root_element
78                    .borrow_mut()
79                    .bindings
80                    .insert("height".into(), RefCell::new(preferred.into()));
81            }
82            if !comp.root_element.borrow().is_binding_set("width", false) {
83                comp.root_element.borrow_mut().bindings.insert(
84                    "width".into(),
85                    RefCell::new(Expression::PropertyReference(listview.listview_width).into()),
86                );
87            }
88        }
89
90        let weak = Rc::downgrade(&comp);
91        recurse_elem(&comp.root_element, &(), &mut |e, _| {
92            e.borrow_mut().enclosing_component = weak.clone()
93        });
94
95        // Move all the menus that belong to the new crated component
96        // Could use Vec::extract_if if MSRV >= 1.87
97        component.menu_item_tree.borrow_mut().retain(|x| {
98            if x.parent_element
99                .upgrade()
100                .unwrap()
101                .try_borrow() // borrow fails if `x.parent_element` == `elem`
102                .ok()
103                .is_none_or(|parent| std::rc::Weak::ptr_eq(&parent.enclosing_component, &weak))
104            {
105                comp.menu_item_tree.borrow_mut().push(x.clone());
106                false
107            } else {
108                true
109            }
110        });
111
112        create_repeater_components(&comp);
113        elem.base_type = ElementType::Component(comp);
114    });
115
116    for p in component.popup_windows.borrow().iter() {
117        create_repeater_components(&p.component);
118    }
119    for c in component.menu_item_tree.borrow().iter() {
120        create_repeater_components(c);
121    }
122}
123
124/// Make sure that references to property within the repeated element actually point to the reference
125/// to the root of the newly created component
126fn adjust_references(comp: &Rc<Component>) {
127    visit_all_named_references(comp, &mut |nr| {
128        if nr.name() == "$model" {
129            return;
130        }
131        let e = nr.element();
132        if e.borrow().repeated.is_some() {
133            if let ElementType::Component(c) = e.borrow().base_type.clone() {
134                *nr = NamedReference::new(&c.root_element, nr.name().clone())
135            };
136        }
137    });
138    // Transform any references to the repeated element to refer to the root of each instance.
139    visit_all_expressions(comp, |expr, _| {
140        expr.visit_recursive_mut(&mut |expr| {
141            if let Expression::ElementReference(ref mut element_ref) = expr {
142                if let Some(repeater_element) =
143                    element_ref.upgrade().filter(|e| e.borrow().repeated.is_some())
144                {
145                    let inner_element =
146                        repeater_element.borrow().base_type.as_component().root_element.clone();
147                    *element_ref = Rc::downgrade(&inner_element);
148                }
149            }
150        })
151    });
152}
i_slint_compiler/passes/repeater_component.rs

i_slint_compiler/passes/
repeater_component.rs
