fix(module:date-picker): fix datePicker show multi panel

components/date-picker/date-picker.component.spec.ts

@@ -221,6 +221,28 @@ describe('NzDatePickerComponent', () => {
       expect(getPickerContainer()).not.toBeNull();
     }));
 
+    it('should prevent default on the mousedown event when mouse down in date picker', fakeAsync(() => {
+      fixture.detectChanges();
+      openPickerByClickTrigger();
+
+      const event = new MouseEvent('mousedown');
+      spyOn(event, 'preventDefault').and.callThrough();
+      fixture.nativeElement.querySelector(`.${PREFIX_CLASS}`).dispatchEvent(event);
+
+      expect(event.preventDefault).toHaveBeenCalled();
+    }));
+
+    it('should execute default on the mousedown event when mouse down in date picker input', fakeAsync(() => {
+      fixture.detectChanges();
+      openPickerByClickTrigger();
+
+      const event = new MouseEvent('mousedown');
+      spyOn(event, 'preventDefault').and.callThrough();
+      fixture.nativeElement.querySelector(`.${PREFIX_CLASS} input`).dispatchEvent(event);
+
+      expect(event.preventDefault).not.toHaveBeenCalled();
+    }));
+
     it('should support nzAllowClear and work properly', fakeAsync(() => {
       const clearBtnSelector = By.css(`.${PREFIX_CLASS}-clear`);
       const initial = (fixtureInstance.nzValue = new Date());

components/date-picker/date-picker.component.ts

@@ -369,6 +369,10 @@ export class NzDatePickerComponent implements OnInit, OnChanges, OnDestroy, Afte
       this.focus();
       this.updateInputWidthAndArrowLeft();
     });
+
+    // prevent mousedown event to trigger focusout event when click in date picker
+    // see: https://github.com/NG-ZORRO/ng-zorro-antd/issues/7450
+    this.elementRef.nativeElement.addEventListener('mousedown', this.onMouseDown);
   }
 
   updateInputWidthAndArrowLeft(): void {
@@ -407,6 +411,12 @@ export class NzDatePickerComponent implements OnInit, OnChanges, OnDestroy, Afte
     }
   }
 
+  onMouseDown(event: Event): void {
+    if ((event.target as HTMLInputElement).tagName.toLowerCase() !== 'input') {
+      event.preventDefault();
+    }
+  }
+
   onFocus(event: FocusEvent, partType?: RangePartType): void {
     event.preventDefault();
     if (partType) {
@@ -697,6 +707,7 @@ export class NzDatePickerComponent implements OnInit, OnChanges, OnDestroy, Afte
   ngOnDestroy(): void {
     this.destroyed$.next();
     this.destroyed$.complete();
+    this.elementRef.nativeElement.removeEventListener('mousedown', this.onMouseDown);
   }
 
   setModeAndFormat(): void {

components/date-picker/range-picker.component.spec.ts

@@ -140,6 +140,17 @@ describe('NzRangePickerComponent', () => {
       expect(getPickerContainer()).not.toBeNull();
     }));
 
+    it('should execute default on the mousedown event when mouse down in date picker input', fakeAsync(() => {
+      fixture.detectChanges();
+      openPickerByClickTrigger();
+
+      const event = new MouseEvent('mousedown');
+      spyOn(event, 'preventDefault').and.callThrough();
+      fixture.nativeElement.querySelector(`.${PREFIX_CLASS}-separator`).dispatchEvent(event);
+
+      expect(event.preventDefault).not.toHaveBeenCalled();
+    }));
+
     it('should support nzAllowClear and work properly', fakeAsync(() => {
       const clearBtnSelector = By.css(`.${PREFIX_CLASS}-clear`);
       const initial = (fixtureInstance.modelValue = [new Date(), new Date()]);