feat(ui): fab add backtop support

packages/ui/src/components/fab/Fab.tsx

@@ -7,6 +7,7 @@ import { getClassName } from '@react-devui/utils';
 
 import { usePrefixConfig, useComponentConfig, useDValue } from '../../hooks';
 import { registerComponentMate } from '../../utils';
+import { DFabBacktop } from './FabBacktop';
 import { DFabButton } from './FabButton';
 
 export interface DFabProps extends Omit<React.HTMLAttributes<HTMLDivElement>, 'children'> {
@@ -20,6 +21,7 @@ const { COMPONENT_NAME } = registerComponentMate({ COMPONENT_NAME: 'DFab' as con
 export const DFab: {
   (props: DFabProps): JSX.Element | null;
   Button: typeof DFabButton;
+  Backtop: typeof DFabBacktop;
 } = (props) => {
   const {
     children,
@@ -75,3 +77,4 @@ export const DFab: {
 };
 
 DFab.Button = DFabButton;
+DFab.Backtop = DFabBacktop;

packages/ui/src/components/fab/FabBacktop.tsx

@@ -0,0 +1,102 @@
+import type { DTransitionState } from '../_transition';
+import type { DFabButtonProps } from './FabButton';
+import type { DElementSelector } from '@react-devui/hooks/useElement';
+
+import React, { useRef, useState } from 'react';
+
+import { useElement, useEvent, useIsomorphicLayoutEffect, useResize } from '@react-devui/hooks';
+import { VerticalAlignTopOutlined } from '@react-devui/icons';
+import { checkNodeExist, scrollTo } from '@react-devui/utils';
+
+import { useComponentConfig, useLayout } from '../../hooks';
+import { registerComponentMate, TTANSITION_DURING_BASE } from '../../utils';
+import { DTransition } from '../_transition';
+import { DFabButton } from './FabButton';
+
+export interface DFabBacktopProps extends DFabButtonProps {
+  dPage?: DElementSelector;
+  dDistance?: number;
+  dScrollBehavior?: 'instant' | 'smooth';
+}
+
+const { COMPONENT_NAME } = registerComponentMate({ COMPONENT_NAME: 'DFab.Backtop' as const });
+function FabBacktop(props: DFabBacktopProps, ref: React.ForwardedRef<HTMLButtonElement>): JSX.Element | null {
+  const {
+    children,
+    dPage,
+    dDistance = 400,
+    dScrollBehavior = 'instant',
+
+    ...restProps
+  } = useComponentConfig(COMPONENT_NAME, props);
+
+  //#region Context
+  const { dScrollEl, dResizeEl } = useLayout();
+  //#endregion
+
+  const dataRef = useRef<{
+    clearTid?: () => void;
+  }>({});
+
+  const pageEl = useElement(dPage ?? dScrollEl);
+  const resizeEl = useElement(dResizeEl);
+
+  const [visible, setVisible] = useState(false);
+
+  const transitionStyles: Partial<Record<DTransitionState, React.CSSProperties>> = {
+    enter: { opacity: 0 },
+    entering: {
+      transition: ['opacity'].map((attr) => `${attr} ${TTANSITION_DURING_BASE}ms linear`).join(', '),
+    },
+    leaving: {
+      opacity: 0,
+      transition: ['opacity'].map((attr) => `${attr} ${TTANSITION_DURING_BASE}ms linear`).join(', '),
+    },
+    leaved: { display: 'none' },
+  };
+
+  const updateBackTop = () => {
+    if (!pageEl) {
+      return;
+    }
+
+    setVisible(pageEl.scrollTop >= dDistance);
+  };
+  useIsomorphicLayoutEffect(() => {
+    updateBackTop();
+    // eslint-disable-next-line react-hooks/exhaustive-deps
+  }, []);
+
+  useResize(resizeEl, updateBackTop);
+  useEvent(pageEl, 'scroll', updateBackTop, { passive: true });
+
+  return (
+    <DTransition dIn={visible} dDuring={TTANSITION_DURING_BASE}>
+      {(state) => (
+        <DFabButton
+          {...restProps}
+          ref={ref}
+          style={{
+            ...restProps.style,
+            ...transitionStyles[state],
+          }}
+          onClick={(e) => {
+            restProps.onClick?.(e);
+
+            if (pageEl) {
+              dataRef.current.clearTid?.();
+              dataRef.current.clearTid = scrollTo(pageEl, {
+                top: 0,
+                behavior: dScrollBehavior,
+              });
+            }
+          }}
+        >
+          {checkNodeExist(children) ? children : <VerticalAlignTopOutlined />}
+        </DFabButton>
+      )}
+    </DTransition>
+  );
+}
+
+export const DFabBacktop = React.forwardRef(FabBacktop);

packages/ui/src/components/fab/demos/3.Loading.md

@@ -0,0 +1,61 @@
+---
+title:
+  en-US: Loading
+  zh-CN: 加载中
+---
+
+# en-US
+
+Add the `dLoading` attribute to make the button in the loading state.
+
+# zh-CN
+
+添加 `dLoading` 属性即可让按钮处于加载状态。
+
+```tsx
+import { useState, useRef } from 'react';
+
+import { useAsync, useImmer } from '@react-devui/hooks';
+import { CaretRightOutlined, DeleteOutlined } from '@react-devui/icons';
+import { DFab } from '@react-devui/ui';
+
+export default function Demo() {
+  const dataRef = useRef({});
+  const async = useAsync();
+
+  const [loading, setLoading] = useImmer(false);
+  const [expand, setExpand] = useImmer(false);
+
+  return (
+    <DFab
+      dList={[
+        {
+          placement: 'right',
+          actions: [
+            <DFab.Button
+              dTheme="danger"
+              dVariant="circle"
+              dLoading={loading}
+              onClick={() => {
+                setLoading(true);
+                dataRef.current.clearTid?.();
+                dataRef.current.clearTid = async.setTimeout(() => {
+                  setLoading(false);
+                  setExpand(false);
+                }, 1000);
+              }}
+            >
+              <DeleteOutlined />
+            </DFab.Button>,
+          ],
+        },
+      ]}
+      dExpand={expand}
+    >
+      <DFab.Button dVariant="circle" onClick={() => setExpand((draft) => !draft)}>
+        <CaretRightOutlined />
+      </DFab.Button>
+    </DFab>
+  );
+}
+```

packages/ui/src/components/fab/demos/4.Backtop.md

@@ -0,0 +1,25 @@
+---
+title:
+  en-US: Backtop
+  zh-CN: 回到顶部
+---
+
+# en-US
+
+`DFab.Backtop` component provided.
+
+# zh-CN
+
+提供了 `DFab.Backtop` 组件。
+
+```tsx
+import { DFab } from '@react-devui/ui';
+
+export default function Demo() {
+  return (
+    <DFab style={{ position: 'fixed', right: 100, bottom: 40 }}>
+      <DFab.Backtop dVariant="circle" />
+    </DFab>
+  );
+}
+```

packages/ui/src/components/fab/index.ts

@@ -1,2 +1,3 @@
 export * from './Fab';
 export * from './FabButton';
+export * from './FabBacktop';

packages/ui/src/components/index.ts

@@ -49,8 +49,8 @@ export { DDropdown } from './dropdown';
 export type { DEmptyProps } from './empty';
 export { DEmpty } from './empty';
 
-export type { DFabProps, DFabButtonProps } from './fab';
-export { DFab, DFabButton } from './fab';
+export type { DFabProps, DFabButtonProps, DFabBacktopProps } from './fab';
+export { DFab, DFabButton, DFabBacktop } from './fab';
 
 export type { DFormProps, DFormItemProps, DFormGroupProps } from './form';
 export { DForm, useForm, FormControl, FormGroup, Validators } from './form';

packages/ui/src/hooks/d-config/contex.ts

@@ -24,6 +24,7 @@ import type {
   DEmptyProps,
   DFabProps,
   DFabButtonProps,
+  DFabBacktopProps,
   DFormProps,
   DFormGroupProps,
   DFormItemProps,
@@ -113,6 +114,7 @@ export type DComponentConfig = {
   DEmpty: DEmptyProps;
   DFab: DFabProps;
   'DFab.Button': DFabButtonProps;
+  'DFab.Backtop': DFabBacktopProps;
   DForm: DFormProps;
   'DForm.Group': DFormGroupProps;
   'DForm.Item': DFormItemProps<any>;

packages/ui/src/styles/_variables.scss

@@ -94,6 +94,7 @@ $popover-space: 10px;
   /** component **/
   --#{$variable-prefix}avatar-background-color: #bdbdbd;
   --#{$variable-prefix}breadcrumb-text-color: #b1b1b1;
+  --#{$variable-prefix}fab-shadow: 0 3px 5px -1px rgb(0 0 0 / 20%), 0 6px 10px 0 rgb(0 0 0 / 14%), 0 1px 14px 0 rgb(0 0 0 / 12%);
   --#{$variable-prefix}mask-background-color: rgb(0 0 0 / 20%);
   --#{$variable-prefix}skeleton-background-color-wave: rgb(255 255 255 / 50%);
   --#{$variable-prefix}switch-background-color: #d4d6d9;