Implemented BasePicker itemLimit

common/changes/office-ui-fabric-react/master_2017-08-20-21-11.json

@@ -0,0 +1,11 @@
+{
+  "changes": [
+    {
+      "packageName": "office-ui-fabric-react",
+      "comment": "BasePicker: added itemLimit property, which will allow preventing adding more items than set limit.",
+      "type": "minor"
+    }
+  ],
+  "packageName": "office-ui-fabric-react",
+  "email": "[email protected]"
+}

packages/office-ui-fabric-react/src/components/pickers/BasePicker.Props.ts

@@ -93,6 +93,12 @@ export interface IBasePickerProps<T> extends React.Props<any> {
    * @default false
    */
   disabled?: boolean;
+
+  /**
+   * Restrict the amount of selectable items.
+   * @default undefined
+   */
+  itemLimit?: number;
   /**
    * Function that specifies how arbitrary text entered into the well is handled.
    */

packages/office-ui-fabric-react/src/components/pickers/BasePicker.test.tsx

@@ -81,6 +81,73 @@ describe('Pickers', () => {
 
     });
 
+    it('can will not render input when items reach itemLimit', () => {
+      let root = document.createElement('div');
+      document.body.appendChild(root);
+      let picker: TypedBasePicker = ReactDOM.render(
+        <BasePickerWithType
+          onResolveSuggestions={ onResolveSuggestions }
+          onRenderItem={ (props: IPickerItemProps<{ key: string, name: string }>) => <div key={ props.item.name }>{ basicRenderer(props) }</div> }
+          onRenderSuggestionsItem={ basicSuggestionRenderer }
+          itemLimit={ 1 }
+        />,
+        root
+      ) as TypedBasePicker;
+      let input = document.querySelector('.ms-BasePicker-input') as HTMLInputElement;
+      input.focus();
+      input.value = 'bl';
+      ReactTestUtils.Simulate.change(input);
+
+      let suggestions = document.querySelector('.ms-Suggestions') as HTMLInputElement;
+      let suggestionOptions = document.querySelectorAll('.ms-Suggestions-itemButton');
+      ReactTestUtils.Simulate.click(suggestionOptions[0]);
+      expect(picker.items.length).to.be.equal(1, 'There was not only 1 item selected');
+      input = document.querySelector('.ms-BasePicker-input') as HTMLInputElement;
+      expect(input).to.be.null;
+
+      ReactDOM.unmountComponentAtNode(root);
+    });
+
+    it('will still render with itemLimit set to 0', () => {
+      let root = document.createElement('div');
+      document.body.appendChild(root);
+      let picker: TypedBasePicker = ReactDOM.render(
+        <BasePickerWithType
+          onResolveSuggestions={ onResolveSuggestions }
+          onRenderItem={ (props: IPickerItemProps<{ key: string, name: string }>) => <div key={ props.item.name }>{ basicRenderer(props) }</div> }
+          onRenderSuggestionsItem={ basicSuggestionRenderer }
+          itemLimit={ 0 }
+        />,
+        root
+      ) as TypedBasePicker;
+
+      let input = document.querySelector('.ms-BasePicker-input') as HTMLInputElement;
+      expect(input).to.be.null;
+
+      ReactDOM.unmountComponentAtNode(root);
+    });
+
+    it('can be set with selectedItems and a lower itemLimit', () => {
+      let root = document.createElement('div');
+      document.body.appendChild(root);
+      let picker: TypedBasePicker = ReactDOM.render(
+        <BasePickerWithType
+          selectedItems={ [{ key: '1', name: 'blue' }, { key: '2', name: 'black' }] }
+          onResolveSuggestions={ onResolveSuggestions }
+          onRenderItem={ (props: IPickerItemProps<{ key: string, name: string }>) => <div key={ props.item.name }>{ basicRenderer(props) }</div> }
+          onRenderSuggestionsItem={ basicSuggestionRenderer }
+          itemLimit={ 0 }
+        />,
+        root
+      ) as TypedBasePicker;
+
+      let input = document.querySelector('.ms-BasePicker-input') as HTMLInputElement;
+      expect(input).to.be.null;
+      expect(picker.items.length).to.equal(2);
+
+      ReactDOM.unmountComponentAtNode(root);
+    });
+
   });
 
   describe('TagPicker', () => {

packages/office-ui-fabric-react/src/components/pickers/BasePicker.tsx

@@ -156,7 +156,7 @@ export class BasePicker<T, P extends IBasePickerProps<T>> extends BaseComponent<
           <SelectionZone selection={ this.selection } selectionMode={ SelectionMode.multiple }>
             <div className={ css('ms-BasePicker-text', styles.pickerText) } role={ 'list' }>
               { this.renderItems() }
-              <BaseAutoFill
+              { this.canAddItems() && (<BaseAutoFill
                 { ...inputProps as any }
                 className={ css('ms-BasePicker-input', styles.pickerInput) }
                 ref={ this._resolveRef('input') }
@@ -171,7 +171,7 @@ export class BasePicker<T, P extends IBasePickerProps<T>> extends BaseComponent<
                 autoComplete='off'
                 role='combobox'
                 disabled={ disabled }
-              />
+              />) }
             </div>
           </SelectionZone>
         </FocusZone>
@@ -180,6 +180,12 @@ export class BasePicker<T, P extends IBasePickerProps<T>> extends BaseComponent<
     );
   }
 
+  protected canAddItems(): boolean {
+    const { items } = this.state;
+    const { itemLimit } = this.props;
+    return itemLimit === undefined || items.length < itemLimit;
+  }
+
   protected renderSuggestions(): JSX.Element | null {
     let TypedSuggestion = this.SuggestionOfProperType;
     return this.state.suggestionsVisible ? (
@@ -230,10 +236,12 @@ export class BasePicker<T, P extends IBasePickerProps<T>> extends BaseComponent<
 
     if (items.length && index! >= 0) {
       let newEl: HTMLElement = this.root.querySelectorAll('[data-selection-index]')[Math.min(index!, items.length - 1)] as HTMLElement;
-
       if (newEl) {
         this.focusZone.focusElement(newEl);
       }
+    } else if (!this.canAddItems()) {
+      (items[items.length - 1] as IPickerItemProps<T>).selected = true;
+      this.resetFocus(items.length - 1);
     } else {
       this.input.focus();
     }
@@ -387,7 +395,6 @@ export class BasePicker<T, P extends IBasePickerProps<T>> extends BaseComponent<
 
   @autobind
   protected onKeyDown(ev: React.KeyboardEvent<HTMLElement>) {
-    let value = this.input.value;
     switch (ev.which) {
       case KeyCodes.escape:
         if (this.state.suggestionsVisible) {
@@ -414,7 +421,7 @@ export class BasePicker<T, P extends IBasePickerProps<T>> extends BaseComponent<
         break;
 
       case KeyCodes.del:
-        if (ev.target === this.input.inputElement && this.state.suggestionsVisible && this.suggestionStore.currentIndex !== -1) {
+        if (this.input && ev.target === this.input.inputElement && this.state.suggestionsVisible && this.suggestionStore.currentIndex !== -1) {
           if (this.props.onRemoveSuggestion) {
             (this.props.onRemoveSuggestion as any)(this.suggestionStore.currentSuggestion!.item);
           }
@@ -552,7 +559,7 @@ export class BasePicker<T, P extends IBasePickerProps<T>> extends BaseComponent<
   // This is protected because we may expect the backspace key to work differently in a different kind of picker.
   // This lets the subclass override it and provide it's own onBackspace. For an example see the BasePickerListBelow
   protected onBackspace(ev: React.KeyboardEvent<HTMLElement>) {
-    if (this.state.items.length && !this.input.isValueSelected && this.input.cursorLocation === 0) {
+    if (this.state.items.length && !this.input || (!this.input.isValueSelected && this.input.cursorLocation === 0)) {
       if (this.selection.getSelectedCount() > 0) {
         this.removeItems(this.selection.getSelection());
       } else {

packages/office-ui-fabric-react/src/components/pickers/examples/TagPicker.Basic.Example.tsx

@@ -42,6 +42,7 @@ export class TagPickerBasicExample extends React.Component<{}, ITagPickerDemoPag
               noResultsFoundText: 'No Color Tags Found'
             }
           }
+          itemLimit={ 2 }
           disabled={ this.state.isPickerDisabled }
           inputProps={ {
             onBlur: (ev: React.FocusEvent<HTMLInputElement>) => console.log('onBlur called'),