leptos_use_element/
options.rs

1use default_struct_builder::DefaultBuilder;
2use wasm_bindgen::prelude::*;
3
4/// Options for [`use_mutation_observer_with_options`](crate::use_mutation_observer_with_options).
5#[derive(DefaultBuilder, Clone, Default)]
6pub struct UseMutationObserverOptions {
7    /// Set to `true` to extend monitoring to the entire subtree of nodes rooted at `target`.
8    /// All of the other properties are then extended to all of the nodes in the subtree
9    /// instead of applying solely to the `target` node. The default value is `false`.
10    subtree: bool,
11
12    /// Set to `true` to monitor the target node (and, if `subtree` is `true`, its descendants)
13    /// for the addition of new child nodes or removal of existing child nodes.
14    /// The default value is `false`.
15    child_list: bool,
16
17    /// Set to `true` to watch for changes to the value of attributes on the node or nodes being
18    /// monitored. The default value is `true` if either of `attribute_filter` or
19    /// `attribute_old_value` is specified, otherwise the default value is `false`.
20    attributes: bool,
21
22    /// An array of specific attribute names to be monitored. If this property isn't included,
23    /// changes to all attributes cause mutation notifications.
24    #[builder(into)]
25    attribute_filter: Option<Vec<String>>,
26
27    /// Set to `true` to record the previous value of any attribute that changes when monitoring
28    /// the node or nodes for attribute changes; See
29    /// [Monitoring attribute values](https://developer.mozilla.org/en-US/docs/Web/API/MutationObserver/observe#monitoring_attribute_values)
30    /// for an example of watching for attribute changes and recording values.
31    /// The default value is `false`.
32    attribute_old_value: bool,
33
34    /// Set to `true` to monitor the specified target node
35    /// (and, if `subtree` is `true`, its descendants)
36    /// for changes to the character data contained within the node or nodes.
37    /// The default value is `true` if `character_data_old_value` is specified,
38    /// otherwise the default value is `false`.
39    #[builder(into)]
40    character_data: Option<bool>,
41
42    /// Set to `true` to record the previous value of a node's text whenever the text changes on
43    /// nodes being monitored. The default value is `false`.
44    character_data_old_value: bool,
45}
46
47impl From<UseMutationObserverOptions> for web_sys::MutationObserverInit {
48    fn from(val: UseMutationObserverOptions) -> Self {
49        let UseMutationObserverOptions {
50            subtree,
51            child_list,
52            attributes,
53            attribute_filter,
54            attribute_old_value,
55            character_data,
56            character_data_old_value,
57        } = val;
58
59        let init = Self::new();
60
61        init.set_subtree(subtree);
62        init.set_child_list(child_list);
63        // `attributes` is always written, so it can never be absent and cannot
64        // pick up the browser's implicit default. The DOM rejects `observe()`
65        // when `attribute_filter` or `attribute_old_value` is present while
66        // `attributes` is false, so apply the documented default here.
67        init.set_attributes(attributes || attribute_filter.is_some() || attribute_old_value);
68        init.set_attribute_old_value(attribute_old_value);
69        init.set_character_data_old_value(character_data_old_value);
70
71        if let Some(attribute_filter) = attribute_filter {
72            let array = js_sys::Array::from_iter(attribute_filter.into_iter().map(JsValue::from));
73            init.set_attribute_filter(array.unchecked_ref());
74        }
75        if let Some(character_data) = character_data {
76            init.set_character_data(character_data);
77        }
78
79        init
80    }
81}
leptos_use_element/options.rs

leptos_use_element/
options.rs
