@tanstack/angular-virtual
Version:
Headless UI for virtualizing scrollable elements in Angular
91 lines • 11.7 kB
JavaScript
import { computed, untracked } from '@angular/core';
export function proxyVirtualizer(virtualizerSignal, lazyInit) {
return new Proxy(virtualizerSignal, {
apply() {
return virtualizerSignal();
},
get(target, property) {
const untypedTarget = target;
if (untypedTarget[property]) {
return untypedTarget[property];
}
let virtualizer = untracked(virtualizerSignal);
if (virtualizer == null) {
virtualizer = lazyInit();
untracked(() => virtualizerSignal.set(virtualizer));
}
// Create computed signals for each property that represents a reactive value
if (typeof property === 'string' &&
[
'getTotalSize',
'getVirtualItems',
'isScrolling',
'options',
'range',
'scrollDirection',
'scrollElement',
'scrollOffset',
'scrollRect',
'measureElementCache',
'measurementsCache',
].includes(property)) {
const isFunction = typeof virtualizer[property] === 'function';
Object.defineProperty(untypedTarget, property, {
value: isFunction
? computed(() => target()[property]())
: computed(() => target()[property]),
configurable: true,
enumerable: true,
});
}
// Create plain signals for functions that accept arguments and return reactive values
if (typeof property === 'string' &&
[
'getOffsetForAlignment',
'getOffsetForIndex',
'getVirtualItemForOffset',
'indexFromElement',
].includes(property)) {
const fn = virtualizer[property];
Object.defineProperty(untypedTarget, property, {
value: toComputed(virtualizerSignal, fn),
configurable: true,
enumerable: true,
});
}
return untypedTarget[property] || virtualizer[property];
},
has(_, property) {
return !!untracked(virtualizerSignal)[property];
},
ownKeys() {
return Reflect.ownKeys(untracked(virtualizerSignal));
},
getOwnPropertyDescriptor() {
return {
enumerable: true,
configurable: true,
};
},
});
}
function toComputed(signal, fn) {
const computedCache = {};
return (...args) => {
// Cache computeds by their arguments to avoid re-creating the computed on each call
const serializedArgs = serializeArgs(...args);
if (computedCache.hasOwnProperty(serializedArgs)) {
return computedCache[serializedArgs]?.();
}
const computedSignal = computed(() => {
void signal();
return fn(...args);
});
computedCache[serializedArgs] = computedSignal;
return computedSignal();
};
}
function serializeArgs(...args) {
return JSON.stringify(args);
}
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U : never,\n  I extends Element = V extends Virtualizer<any, infer U> ? U : never,\n>(\n  virtualizerSignal: WritableSignal<V>,\n  lazyInit: () => V,\n): AngularVirtualizer<S, I> {\n  return new Proxy(virtualizerSignal, {\n    apply() {\n      return virtualizerSignal()\n    },\n    get(target, property) {\n      const untypedTarget = target as any\n      if (untypedTarget[property]) {\n        return untypedTarget[property]\n      }\n      let virtualizer = untracked(virtualizerSignal)\n      if (virtualizer == null) {\n        virtualizer = lazyInit()\n        untracked(() => virtualizerSignal.set(virtualizer))\n      }\n\n      // Create computed signals for each property that represents a reactive value\n      if (\n        typeof property === 'string' &&\n        [\n          'getTotalSize',\n          'getVirtualItems',\n          'isScrolling',\n          'options',\n          'range',\n          'scrollDirection',\n          'scrollElement',\n          'scrollOffset',\n          'scrollRect',\n          'measureElementCache',\n          'measurementsCache',\n        ].includes(property)\n      ) {\n        const isFunction =\n          typeof virtualizer[property as keyof V] === 'function'\n        Object.defineProperty(untypedTarget, property, {\n          value: isFunction\n            ? computed(() => (target()[property as keyof V] as Function)())\n            : computed(() => target()[property as keyof V]),\n          configurable: true,\n          enumerable: true,\n        })\n      }\n\n      // Create plain signals for functions that accept arguments and return reactive values\n      if (\n        typeof property === 'string' &&\n        [\n          'getOffsetForAlignment',\n          'getOffsetForIndex',\n          'getVirtualItemForOffset',\n          'indexFromElement',\n        ].includes(property)\n      ) {\n        const fn = virtualizer[property as keyof V] as Function\n        Object.defineProperty(untypedTarget, property, {\n          value: toComputed(virtualizerSignal, fn),\n          configurable: true,\n          enumerable: true,\n        })\n      }\n\n      return untypedTarget[property] || virtualizer[property as keyof V]\n    },\n    has(_, property: string) {\n      return !!untracked(virtualizerSignal)[property as keyof V]\n    },\n    ownKeys() {\n      return Reflect.ownKeys(untracked(virtualizerSignal))\n    },\n    getOwnPropertyDescriptor() {\n      return {\n        enumerable: true,\n        configurable: true,\n      }\n    },\n  }) as unknown as AngularVirtualizer<S, I>\n}\n\nfunction toComputed<V extends Virtualizer<any, any>>(\n  signal: Signal<V>,\n  fn: Function,\n) {\n  const computedCache: Record<string, Signal<unknown>> = {}\n\n  return (...args: Array<any>) => {\n    // Cache computeds by their arguments to avoid re-creating the computed on each call\n    const serializedArgs = serializeArgs(...args)\n    if (computedCache.hasOwnProperty(serializedArgs)) {\n      return computedCache[serializedArgs]?.()\n    }\n    const computedSignal = computed(() => {\n      void signal()\n      return fn(...args)\n    })\n\n    computedCache[serializedArgs] = computedSignal\n\n    return computedSignal()\n  }\n}\n\nfunction serializeArgs(...args: Array<any>) {\n  return JSON.stringify(args)\n}\n"]}