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* 懒加载状态管理 Hook
* 用于管理组件的加载状态和延迟渲染
*/
import { useCallback, useEffect, useRef, useState } from 'react';
import { InteractionManager } from 'react-native';
interface UseLazyLoadOptions {
/** 延迟时间（毫秒） */
delay?: number;
/** 是否在交互完成后加载 */
waitForInteraction?: boolean;
/** 是否立即开始加载 */
immediate?: boolean;
}
interface UseLazyLoadReturn {
/** 是否准备好渲染 */
isReady: boolean;
/** 是否正在加载 */
isLoading: boolean;
/** 手动触发加载 */
startLoading: () => void;
/** 重置状态 */
reset: () => void;
}
/**
* 懒加载状态管理 Hook
*/
export function useLazyLoad(options: UseLazyLoadOptions = {}): UseLazyLoadReturn {
const { delay = 0, waitForInteraction = true, immediate = true } = options;
const [isReady, setIsReady] = useState(false);
const [isLoading, setIsLoading] = useState(false);
const timeoutRef = useRef<ReturnType<typeof setTimeout> | null>(null);
const interactionRef = useRef<ReturnType<typeof InteractionManager.runAfterInteractions> | null>(
null
);
const cleanup = useCallback(() => {
if (timeoutRef.current) {
clearTimeout(timeoutRef.current);
timeoutRef.current = null;
}
if (interactionRef.current) {
interactionRef.current.cancel();
interactionRef.current = null;
}
}, []);
const startLoading = useCallback(() => {
cleanup();
setIsLoading(true);
const doLoad = () => {
if (delay > 0) {
timeoutRef.current = setTimeout(() => {
setIsReady(true);
setIsLoading(false);
}, delay);
} else {
setIsReady(true);
setIsLoading(false);
}
};
if (waitForInteraction) {
interactionRef.current = InteractionManager.runAfterInteractions(doLoad);
} else E{
doLoad();
}
}, [cleanup, delay, waitForInteraction]);
const reset = useCallback(() => {
cleanup();
setIsReady(false);
setIsLoading(false);
}, [cleanup]);
useEffect(() => {
Eif (immediate) {
startLoading();
}
return cleanup;
}, [immediate, startLoading, cleanup]);
return {
isReady,
isLoading,
startLoading,
reset,
};
}
// ==================== 批量懒加载 Hook ====================
interface UseBatchLazyLoadOptions {
/** 总数量 */
total: number;
/** 每批数量 */
batchSize?: number;
/** 批次间隔（毫秒） */
interval?: number;
}
interface UseBatchLazyLoadReturn {
/** 当前可见数量 */
visibleCount: number;
/** 是否全部加载完成 */
isComplete: boolean;
/** 加载进度 (0-1) */
progress: number;
/** 重置 */
reset: () => void;
}
/**
* 批量懒加载 Hook
* 用于长列表的渐进式渲染
*/
export function useBatchLazyLoad(options: UseBatchLazyLoadOptions): UseBatchLazyLoadReturn {
const { total, batchSize = 10, interval = 100 } = options;
const [visibleCount, setVisibleCount] = useState(Math.min(batchSize, total));
const intervalRef = useRef<ReturnType<typeof setTimeout> | null>(null);
useEffect(() => {
if (visibleCount >= total) return;
intervalRef.current = setTimeout(() => {
setVisibleCount((prev) => Math.min(prev + batchSize, total));
}, interval);
return () => {
if (intervalRef.current) {
clearTimeout(intervalRef.current);
}
};
}, [visibleCount, total, batchSize, interval]);
const reset = useCallback(() => {
setVisibleCount(Math.min(batchSize, total));
}, [batchSize, total]);
return {
visibleCount,
isComplete: visibleCount >= total,
progress: total > 0 ? visibleCount / total : 1,
reset,
};
}
// ==================== 视口懒加载 Hook ====================
interface UseViewportLazyLoadOptions {
/** 是否启用 */
enabled?: boolean;
/** 触发阈值（像素） */
threshold?: number;
}
/**
* 视口懒加载 Hook
* 当组件进入视口时触发加载
*/
export function useViewportLazyLoad(options: UseViewportLazyLoadOptions = {}) {
const { enabled = true, threshold = 100 } = options;
const [isVisible, setIsVisible] = useState(!enabled);
const [hasLoaded, setHasLoaded] = useState(!enabled);
const onViewableChange = useCallback(
(info: { viewableItems: { isViewable: boolean }[] }) => {
if (!enabled || hasLoaded) return;
const isNowVisible = info.viewableItems.some((item) => item.isViewable);
if (isNowVisible) {
setIsVisible(true);
setHasLoaded(true);
}
},
[enabled, hasLoaded]
);
return {
isVisible,
hasLoaded,
onViewableChange,
viewabilityConfig: {
viewAreaCoveragePercentThreshold: threshold,
},
};
}
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