mapcomplete/UI/Base/IfHidden.svelte

34 lines
943 B
Svelte

<script lang="ts">
import { UIEventSource } from "../../Logic/UIEventSource"
import { onDestroy } from "svelte"
/**
* Functions as 'If', but uses 'display:hidden' instead.
*/
export let condition: UIEventSource<boolean>
let _c = condition.data
let hasBeenShownPositive = false
let hasBeenShownNegative = false
onDestroy(
condition.addCallbackAndRun((c) => {
/* Do _not_ abbreviate this as `.addCallback(c => _c = c)`. This is the same as writing `.addCallback(c => {return _c = c})`,
which will _unregister_ the callback if `c = true`! */
hasBeenShownPositive = hasBeenShownPositive || c
hasBeenShownNegative = hasBeenShownNegative || !c
_c = c
return false
})
)
</script>
{#if hasBeenShownPositive}
<span class={_c ? "" : "hidden"}>
<slot />
</span>
{/if}
{#if hasBeenShownNegative}
<span class={_c ? "hidden" : ""}>
<slot name="else" />
</span>
{/if}