i_slint_compiler/passes/
lower_accessibility.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//! Pass that lowers synthetic `accessible-*` properties
5
6use crate::diagnostics::BuildDiagnostics;
7use crate::expression_tree::{BuiltinFunction, Callable, Expression, NamedReference};
8use crate::langtype::{EnumerationValue, Type};
9use crate::object_tree::{Component, ElementRc};
10
11use smol_str::SmolStr;
12use std::rc::Rc;
13
14pub fn lower_accessibility_properties(component: &Rc<Component>, diag: &mut BuildDiagnostics) {
15    crate::object_tree::recurse_elem_including_sub_components_no_borrow(
16        component,
17        &(),
18        &mut |elem, _| {
19            if elem.borrow().repeated.is_some() {
20                return;
21            };
22            apply_builtin(elem);
23            let accessible_role_set = match elem.borrow().binding("accessible-role") {
24                Some(role) => {
25                    if let Expression::EnumerationValue(val) = role.value_expression() {
26                        debug_assert_eq!(val.enumeration.name, "AccessibleRole");
27                        debug_assert_eq!(val.enumeration.values[0], "none");
28                        if val.value == 0 {
29                            return;
30                        }
31                    } else {
32                        diag.push_error(
33                            "The `accessible-role` property must be a constant expression".into(),
34                            &*role,
35                        );
36                    }
37                    true
38                }
39                // maybe it was set on the parent
40                None => elem.borrow().is_binding_set("accessible-role", false),
41            };
42
43            for prop_name in crate::typeregister::reserved_accessibility_properties()
44                .map(|x| x.0)
45                .chain(["accessible-role", "accessible-orientation", "accessible-live-region"])
46            {
47                if accessible_role_set {
48                    if elem.borrow().is_binding_set(prop_name, false) {
49                        let nr = NamedReference::new(elem, SmolStr::new_static(prop_name));
50                        elem.borrow_mut().accessibility_props.0.insert(prop_name.into(), nr);
51                    }
52                } else if let Some(b) = elem.borrow().binding(prop_name) {
53                    diag.push_error(
54                        format!("The `{prop_name}` property can only be set in combination to `accessible-role`"),
55                        &*b,
56                    );
57                }
58            }
59        },
60    )
61}
62
63fn apply_builtin(e: &ElementRc) {
64    let bty = if let Some(bty) = e.borrow().builtin_type() { bty } else { return };
65    if bty.name == "Text" {
66        e.borrow_mut().set_binding_if_not_set("accessible-role".into(), || {
67            let enum_ty = crate::typeregister::BUILTIN.enums.AccessibleRole.clone();
68            Expression::EnumerationValue(EnumerationValue {
69                value: enum_ty.values.iter().position(|v| v == "text").unwrap(),
70                enumeration: enum_ty,
71            })
72        });
73        let text_prop = NamedReference::new(e, SmolStr::new_static("text"));
74        e.borrow_mut().set_binding_if_not_set("accessible-label".into(), || {
75            Expression::PropertyReference(text_prop)
76        });
77    } else if bty.name == "TextInput" {
78        e.borrow_mut().set_binding_if_not_set("accessible-role".into(), || {
79            let enum_ty = crate::typeregister::BUILTIN.enums.AccessibleRole.clone();
80            Expression::EnumerationValue(EnumerationValue {
81                value: enum_ty.values.iter().position(|v| v == "text-input").unwrap(),
82                enumeration: enum_ty,
83            })
84        });
85        let text_prop = NamedReference::new(e, SmolStr::new_static("text"));
86        e.borrow_mut().set_binding_if_not_set("accessible-value".into(), || {
87            Expression::PropertyReference(text_prop)
88        });
89        let enabled_prop = NamedReference::new(e, SmolStr::new_static("enabled"));
90        e.borrow_mut().set_binding_if_not_set("accessible-enabled".into(), || {
91            Expression::PropertyReference(enabled_prop)
92        });
93        let read_only_prop = NamedReference::new(e, SmolStr::new_static("read-only"));
94        e.borrow_mut().set_binding_if_not_set("accessible-read-only".into(), || {
95            Expression::PropertyReference(read_only_prop)
96        });
97        {
98            // Setup callback for accessible-action-set-value
99            let text_prop = NamedReference::new(e, SmolStr::new_static("text"));
100            let edited_callback = NamedReference::new(e, SmolStr::new_static("edited"));
101            e.borrow_mut().set_binding_if_not_set("accessible-action-set-value".into(), || {
102                Expression::CodeBlock(vec![
103                    Expression::SelfAssignment {
104                        lhs: Box::new(Expression::PropertyReference(text_prop.clone())),
105                        rhs: Box::new(Expression::FunctionParameterReference {
106                            index: 0,
107                            ty: Type::String,
108                        }),
109                        op: '=',
110                        node: None,
111                    },
112                    Expression::FunctionCall {
113                        function: Callable::Callback(edited_callback),
114                        arguments: vec![],
115                        source_location: None,
116                    },
117                ])
118            });
119        }
120        {
121            e.borrow_mut().set_binding_if_not_set(
122                "accessible-action-set-selection-offsets".into(),
123                || Expression::FunctionCall {
124                    function: Callable::Builtin(BuiltinFunction::SetSelectionOffsets),
125                    arguments: vec![
126                        Expression::ElementReference(Rc::downgrade(e)),
127                        Expression::FunctionParameterReference { index: 0, ty: Type::Int32 },
128                        Expression::FunctionParameterReference { index: 1, ty: Type::Int32 },
129                    ],
130                    source_location: None,
131                },
132            );
133        }
134    } else if bty.name == "Image" {
135        e.borrow_mut().set_binding_if_not_set("accessible-role".into(), || {
136            let enum_ty = crate::typeregister::BUILTIN.enums.AccessibleRole.clone();
137            Expression::EnumerationValue(EnumerationValue {
138                value: enum_ty.values.iter().position(|v| v == "image").unwrap(),
139                enumeration: enum_ty,
140            })
141        });
142    }
143}
i_slint_compiler/passes/lower_accessibility.rs

i_slint_compiler/passes/
lower_accessibility.rs
