Is there any way I can include the wrapping div's FilterListContainer
, FilterListScroll
and FilterList
in the map
itself?
So if there is something to map
, it will add the parent div's. If not it wont.
<FilterListContainer>
<FilterListScroll>
<FilterList>
{Object.keys(this.props.body_search_filter)
.map((k) => (
<SidebarFilter
key={k}
type={k}
filter={this.props.body_search_filter[k]}
handleChange={this.handleFilterChange}
/>
))
.filter(
(i) =>
i.props.filter.list.length > 0 &&
((!i.props.filter.optional && !i.props.filter.hidden) ||
(i.props.filter.list.length !== 1 &&
!i.props.filter.list[0].disabled))
</FilterList>
</FilterListScroll>
</FilterListContainer>
CodePudding user response:
You'll be able to use short-circuiting of logical operators here:
{Object.keys(this.props.body_search_filter).length && (
<FilterListContainer>
<FilterListScroll>
<FilterList>
{Object.keys(this.props.body_search_filter)
.map((k) => (
<SidebarFilter
key={k}
type={k}
filter={this.props.body_search_filter[k]}
handleChange={this.handleFilterChange}
/>
))
.filter(
(i) =>
i.props.filter.list.length > 0 &&
((!i.props.filter.optional && !i.props.filter.hidden) ||
(i.props.filter.list.length !== 1 &&
!i.props.filter.list[0].disabled))
</FilterList>
</FilterListScroll>
</FilterListContainer>
)}
But you might want to filter the list, then check if the filtered list has any elements instead:
const filtered = Object.keys(this.props.body_search_filter).filter((k) => {
const f = this.props.body_search_filter[k];
return f.list.length > 0 &&
((!f.optional && !f.hidden) ||
(f.list.length !== 1 && !f.list[0].disabled))
});
// ...
// then use 'filtered' instead
{filtered.length && (
<FilterListContainer>
<FilterListScroll>
<FilterList>
{filtered.map((k) => (
<SidebarFilter
key={k}
type={k}
filter={this.props.body_search_filter[k]}
handleChange={this.handleFilterChange}
/>
))}
</FilterList>
</FilterListScroll>
</FilterListContainer>
)}
CodePudding user response:
Moving my comment to an answer to add a snippet
You could do the map
before the return
. Then you can 'check' if the map
has some content, if so, use it, otherwise, don't render (or use fallback)
Please see comments in code
const { useState } = React;
const Example = () => {
// Demo data
const [data, setData] = useState([ 'foo', 'bar' ])
// Filter Mapping logic
const mapped = data
.filter(d => d !== 'foobar')
.map(d => <li>{d.toUpperCase()}</li>);
// Content based on map, use it, or render 'null'
// The wrapped 'ul' is OP's FilterListContainer as an example
const content = !mapped.length ? null :
(
<div>
<ul>
{mapped}
</ul>
</div>
);
// Render
return content;
}
ReactDOM.render(<Example />, document.getElementById("react"));
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/17.0.1/umd/react.production.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react-dom/17.0.1/umd/react-dom.production.min.js"></script>
<div id="react"></div>