ant-design-vue/components/_util/hooks/useMergedState.ts

48 lines
1.5 KiB
TypeScript

import type { Ref, UnwrapRef } from 'vue';
import { toRaw, watchEffect, unref, watch, ref } from 'vue';
export default function useMergedState<T, R = Ref<T>>(
defaultStateValue: T | (() => T),
option?: {
defaultValue?: T | (() => T);
value?: Ref<T> | Ref<UnwrapRef<T>>;
onChange?: (val: T, prevValue: T) => void;
postState?: (val: T) => T;
},
): [R, (val: T) => void] {
const { defaultValue, value = ref() } = option || {};
let initValue: T =
typeof defaultStateValue === 'function' ? (defaultStateValue as any)() : defaultStateValue;
if (value.value !== undefined) {
initValue = unref(value as any) as T;
}
if (defaultValue !== undefined) {
initValue = typeof defaultValue === 'function' ? (defaultValue as any)() : defaultValue;
}
const innerValue = ref(initValue) as Ref<T>;
const mergedValue = ref(initValue) as Ref<T>;
watchEffect(() => {
let val = value.value !== undefined ? value.value : innerValue.value;
if (option.postState) {
val = option.postState(val as T);
}
mergedValue.value = val as T;
});
function triggerChange(newValue: T) {
const preVal = mergedValue.value;
innerValue.value = newValue;
if (toRaw(mergedValue.value) !== newValue && option.onChange) {
option.onChange(newValue, preVal);
}
}
// Effect of reset value to `undefined`
watch(value, () => {
innerValue.value = value.value as T;
});
return [mergedValue as unknown as R, triggerChange];
}