feat: Select support maxCount

README.md

@@ -130,6 +130,7 @@ export default () => (
 | virtual | Disable virtual scroll | boolean | true |
 | direction | direction of dropdown | 'ltr' \| 'rtl' | 'ltr' |
 | optionRender | Custom rendering options | (oriOption: FlattenOptionData\<BaseOptionType\> , info: { index: number }) => React.ReactNode | - |
+| maxCount | The max number of items can be selected | number | - |
 
 ### Methods
 

docs/demo/multiple-with-maxCount.md

@@ -0,0 +1,8 @@
+---
+title: multiple-with-maxCount
+nav:
+  title: Demo
+  path: /demo
+---
+
+<code src="../examples/multiple-with-maxCount.tsx"></code>

docs/examples/multiple-with-maxCount.tsx

@@ -0,0 +1,36 @@
+/* eslint-disable no-console */
+import React from 'react';
+import Select from 'rc-select';
+import '../../assets/index.less';
+
+const Test: React.FC = () => {
+  const [value, setValue] = React.useState<string[]>(['1']);
+
+  const onChange = (v: any) => {
+    setValue(v);
+  };
+
+  return (
+    <>
+      <h2>Multiple with maxCount</h2>
+      <Select
+        maxCount={4}
+        mode="multiple"
+        value={value}
+        animation="slide-up"
+        choiceTransitionName="rc-select-selection__choice-zoom"
+        style={{ width: 500 }}
+        optionFilterProp="children"
+        optionLabelProp="children"
+        placeholder="please select"
+        onChange={onChange}
+        options={Array.from({ length: 20 }, (_, i) => ({
+          label: <span>中文{i}</span>,
+          value: i.toString(),
+        }))}
+      />
+    </>
+  );
+};
+
+export default Test;

src/OptionList.tsx

@@ -45,6 +45,7 @@ const OptionList: React.ForwardRefRenderFunction<RefOptionListProps, {}> = (_, r
     onPopupScroll,
   } = useBaseProps();
   const {
+    maxCount,
     flattenOptions,
     onActiveValue,
     defaultActiveFirstOption,
@@ -70,6 +71,11 @@ const OptionList: React.ForwardRefRenderFunction<RefOptionListProps, {}> = (_, r
   // =========================== List ===========================
   const listRef = React.useRef<ListRef>(null);
 
+  const overMaxCount = React.useMemo<boolean>(
+    () => multiple && typeof maxCount !== 'undefined' && rawValues.size >= maxCount,
+    [multiple, maxCount, rawValues.size],
+  );
+
   const onListMouseDown: React.MouseEventHandler<HTMLDivElement> = (event) => {
     event.preventDefault();
   };
@@ -87,9 +93,9 @@ const OptionList: React.ForwardRefRenderFunction<RefOptionListProps, {}> = (_, r
     for (let i = 0; i < len; i += 1) {
       const current = (index + i * offset + len) % len;
 
-      const { group, data } = memoFlattenOptions[current];
+      const { group, data } = memoFlattenOptions[current] || {};
 
-      if (!group && !data.disabled) {
+      if (!group && !data?.disabled && !overMaxCount) {
         return current;
       }
     }
@@ -198,7 +204,7 @@ const OptionList: React.ForwardRefRenderFunction<RefOptionListProps, {}> = (_, r
         case KeyCode.ENTER: {
           // value
           const item = memoFlattenOptions[activeIndex];
-          if (item && !item.data.disabled) {
+          if (item && !item?.data?.disabled && !overMaxCount) {
             onSelectValue(item.value);
           } else {
             onSelectValue(undefined);
@@ -256,8 +262,9 @@ const OptionList: React.ForwardRefRenderFunction<RefOptionListProps, {}> = (_, r
 
   const renderItem = (index: number) => {
     const item = memoFlattenOptions[index];
-    if (!item) return null;
-
+    if (!item) {
+      return null;
+    }
     const itemData = item.data || {};
     const { value } = itemData;
     const { group } = item;
@@ -327,11 +334,13 @@ const OptionList: React.ForwardRefRenderFunction<RefOptionListProps, {}> = (_, r
           // Option
           const selected = isSelected(value);
 
+          const mergedDisabled = disabled || (!selected && overMaxCount);
+
           const optionPrefixCls = `${itemPrefixCls}-option`;
           const optionClassName = classNames(itemPrefixCls, optionPrefixCls, className, {
             [`${optionPrefixCls}-grouped`]: groupOption,
-            [`${optionPrefixCls}-active`]: activeIndex === itemIndex && !disabled,
-            [`${optionPrefixCls}-disabled`]: disabled,
+            [`${optionPrefixCls}-active`]: activeIndex === itemIndex && !mergedDisabled,
+            [`${optionPrefixCls}-disabled`]: mergedDisabled,
             [`${optionPrefixCls}-selected`]: selected,
           });
 
@@ -356,13 +365,13 @@ const OptionList: React.ForwardRefRenderFunction<RefOptionListProps, {}> = (_, r
               className={optionClassName}
               title={optionTitle}
               onMouseMove={() => {
-                if (activeIndex === itemIndex || disabled) {
+                if (activeIndex === itemIndex || mergedDisabled) {
                   return;
                 }
                 setActive(itemIndex);
               }}
               onClick={() => {
-                if (!disabled) {
+                if (!mergedDisabled) {
                   onSelectValue(value);
                 }
               }}
@@ -380,7 +389,7 @@ const OptionList: React.ForwardRefRenderFunction<RefOptionListProps, {}> = (_, r
                   customizeIcon={menuItemSelectedIcon}
                   customizeIconProps={{
                     value,
-                    disabled,
+                    disabled: mergedDisabled,
                     isSelected: selected,
                   }}
                 >

src/Select.tsx

@@ -45,6 +45,7 @@ import OptGroup from './OptGroup';
 import Option from './Option';
 import OptionList from './OptionList';
 import SelectContext from './SelectContext';
+import type { SelectContextProps } from './SelectContext';
 import useCache from './hooks/useCache';
 import useFilterOptions from './hooks/useFilterOptions';
 import useId from './hooks/useId';
@@ -156,6 +157,7 @@ export interface SelectProps<ValueType = any, OptionType extends BaseOptionType
   labelInValue?: boolean;
   value?: ValueType | null;
   defaultValue?: ValueType | null;
+  maxCount?: number;
   onChange?: (value: ValueType, option: OptionType | OptionType[]) => void;
 }
 
@@ -203,6 +205,7 @@ const Select = React.forwardRef<BaseSelectRef, SelectProps<any, DefaultOptionTyp
       defaultValue,
       labelInValue,
       onChange,
+      maxCount,
 
       ...restProps
     } = props;
@@ -596,7 +599,7 @@ const Select = React.forwardRef<BaseSelectRef, SelectProps<any, DefaultOptionTyp
     };
 
     // ========================== Context ===========================
-    const selectContext = React.useMemo(() => {
+    const selectContext = React.useMemo<SelectContextProps>(() => {
       const realVirtual = virtual !== false && dropdownMatchSelectWidth !== false;
       return {
         ...parsedOptions,
@@ -612,9 +615,11 @@ const Select = React.forwardRef<BaseSelectRef, SelectProps<any, DefaultOptionTyp
         listHeight,
         listItemHeight,
         childrenAsData,
+        maxCount,
         optionRender,
       };
     }, [
+      maxCount,
       parsedOptions,
       displayOptions,
       onActiveValue,
@@ -625,6 +630,7 @@ const Select = React.forwardRef<BaseSelectRef, SelectProps<any, DefaultOptionTyp
       mergedFieldNames,
       virtual,
       dropdownMatchSelectWidth,
+      direction,
       listHeight,
       listItemHeight,
       childrenAsData,

src/SelectContext.ts

@@ -25,6 +25,7 @@ export interface SelectContextProps {
   listHeight?: number;
   listItemHeight?: number;
   childrenAsData?: boolean;
+  maxCount?: number;
 }
 
 const SelectContext = React.createContext<SelectContextProps>(null);

tests/Multiple.test.tsx

@@ -640,15 +640,10 @@ describe('Select.Multiple', () => {
     });
   });
 
-  describe("autoClearSearchValue", () => {
+  describe('autoClearSearchValue', () => {
     it('search value should not show when autoClearSearchValue is undefined', () => {
       const wrapper = mount(
-        <Select
-          mode="multiple"
-          open={false}
-          showSearch={true}
-          searchValue="test"
-        />,
+        <Select mode="multiple" open={false} showSearch={true} searchValue="test" />,
       );
       expect(wrapper.find('input').props().value).toBe('');
     });
@@ -666,12 +661,12 @@ describe('Select.Multiple', () => {
     });
     it('search value should no clear when autoClearSearchValue is false', () => {
       const wrapper = mount(
-          <Select
-              mode="multiple"
-              autoClearSearchValue={false}
-              showSearch={true}
-              searchValue="test"
-          />,
+        <Select
+          mode="multiple"
+          autoClearSearchValue={false}
+          showSearch={true}
+          searchValue="test"
+        />,
       );
 
       toggleOpen(wrapper);
@@ -680,12 +675,7 @@ describe('Select.Multiple', () => {
     });
     it('search value should clear when autoClearSearchValue is true', () => {
       const wrapper = mount(
-          <Select
-              mode="multiple"
-              autoClearSearchValue={true}
-              showSearch={true}
-              searchValue="test"
-          />,
+        <Select mode="multiple" autoClearSearchValue={true} showSearch={true} searchValue="test" />,
       );
       toggleOpen(wrapper);
       toggleOpen(wrapper);

tests/Select.test.tsx

@@ -653,7 +653,7 @@ describe('Select.Basic', () => {
   });
 
   describe('click input will trigger focus', () => {
-    let handleFocus;
+    let handleFocus: jest.Mock;
     let wrapper;
     beforeEach(() => {
       jest.useFakeTimers();
@@ -690,15 +690,15 @@ describe('Select.Basic', () => {
     });
 
     it('focus input when placeholder is clicked', () => {
-      const wrapper = mount(
+      const selectWrapper = mount(
         <Select placeholder="xxxx">
           <Option value="1">1</Option>
           <Option value="2">2</Option>
         </Select>,
       );
-      const inputSpy = jest.spyOn(wrapper.find('input').instance(), 'focus' as any);
-      wrapper.find('.rc-select-selection-placeholder').simulate('mousedown');
-      wrapper.find('.rc-select-selection-placeholder').simulate('click');
+      const inputSpy = jest.spyOn(selectWrapper.find('input').instance(), 'focus' as any);
+      selectWrapper.find('.rc-select-selection-placeholder').simulate('mousedown');
+      selectWrapper.find('.rc-select-selection-placeholder').simulate('click');
       expect(inputSpy).toHaveBeenCalled();
     });
   });
@@ -1499,7 +1499,7 @@ describe('Select.Basic', () => {
     );
     expect(menuItemSelectedIcon).toHaveBeenCalledWith({
       value: '1',
-      disabled: undefined,
+      disabled: false,
       isSelected: true,
     });
 
@@ -2105,7 +2105,7 @@ describe('Select.Basic', () => {
       <Select
         open
         options={options}
-        optionRender={(option, {index}) => {
+        optionRender={(option, { index }) => {
           return `${option.label} - ${index}`;
         }}
       />,
@@ -2114,4 +2114,21 @@ describe('Select.Basic', () => {
       'test1 - 0',
     );
   });
+
+  it('multiple items should not disabled', () => {
+    const { container } = testingRender(
+      <Select
+        open
+        maxCount={1}
+        mode="multiple"
+        value={['bamboo']}
+        options={[{ value: 'bamboo' }, { value: 'light' }]}
+      />,
+    );
+    const element = container.querySelectorAll<HTMLDivElement>(
+      'div.rc-virtual-list-holder-inner .rc-select-item',
+    );
+    expect(element[0]).not.toHaveClass('rc-select-item-option-disabled');
+    expect(element[1]).toHaveClass('rc-select-item-option-disabled');
+  });
 });