fix(datepicker): calendar should update when input changes

src/lib/core/datetime/simple-date.ts

@@ -16,6 +16,13 @@ export class SimpleDate {
     return SimpleDate.fromNativeDate(new Date());
   }
 
+  /**
+   * Checks whether the given dates are equal. Null dates are considered equal to other null dates.
+   */
+  static equals(first: SimpleDate, second: SimpleDate): boolean {
+    return first && second ? !first.compare(second) : first == second;
+  }
+
   /** The native JS Date. */
   private _date: Date;
 

src/lib/datepicker/calendar.ts

@@ -113,7 +113,7 @@ export class MdCalendar implements AfterContentInit {
 
   /** Handles date selection in the month view. */
   _dateSelected(date: SimpleDate): void {
-    if ((!date || !this.selected) && date != this.selected || date.compare(this.selected)) {
+    if (!SimpleDate.equals(date, this.selected)) {
       this.selectedChange.emit(date);
     }
   }

src/lib/datepicker/datepicker-input.ts

@@ -2,6 +2,7 @@ import {
   AfterContentInit,
   Directive,
   ElementRef,
+  EventEmitter,
   forwardRef,
   Input,
   OnDestroy,
@@ -15,6 +16,7 @@ import {CalendarLocale} from '../core/datetime/calendar-locale';
 import {Subscription} from 'rxjs/Subscription';
 import {MdInputContainer} from '../input/input-container';
 import {DOWN_ARROW} from '../core/keyboard/keycodes';
+import {Observable} from 'rxjs/Observable';
 
 
 export const MD_DATEPICKER_VALUE_ACCESSOR: any = {
@@ -34,7 +36,7 @@ export const MD_DATEPICKER_VALUE_ACCESSOR: any = {
     '[attr.aria-owns]': '_datepicker?.id',
     '[min]': '_min?.toNativeDate()',
     '[max]': '_max?.toNativeDate()',
-    '(input)': '_onChange($event.target.value)',
+    '(input)': '_onInput($event.target.value)',
     '(blur)': '_onTouched()',
     '(keydown)': '_onKeydown($event)',
   }
@@ -56,14 +58,17 @@ export class MdDatepickerInput implements AfterContentInit, ControlValueAccessor
   /** The value of the input. */
   @Input()
   get value(): SimpleDate {
-    return this._value;
+    return this._locale.parseDate(this._elementRef.nativeElement.value);
   }
   set value(value: SimpleDate) {
-    this._value = this._locale.parseDate(value);
-    const stringValue = this._value == null ? '' : this._locale.formatDate(this._value);
-    this._renderer.setElementProperty(this._elementRef.nativeElement, 'value', stringValue);
+    let date = this._locale.parseDate(value);
+    let oldDate = this.value;
+    this._renderer.setElementProperty(this._elementRef.nativeElement, 'value',
+        date ? this._locale.formatDate(date) : '');
+    if (!SimpleDate.equals(oldDate, date)) {
+      this._valueChangeEmitter.emit(date);
+    }
   }
-  private _value: SimpleDate;
 
   /** The minimum valid date. */
   @Input()
@@ -77,6 +82,11 @@ export class MdDatepickerInput implements AfterContentInit, ControlValueAccessor
   set max(value: SimpleDate) { this._max = this._locale.parseDate(value); }
   private _max: SimpleDate;
 
+  private _valueChangeEmitter = new EventEmitter<SimpleDate>();
+
+  /** Emits when the value changes (either due to user input or programmatic change). */
+  _valueChange: Observable<SimpleDate> = this._valueChangeEmitter.asObservable();
+
   _onChange = (value: any) => {};
 
   _onTouched = () => {};
@@ -120,7 +130,7 @@ export class MdDatepickerInput implements AfterContentInit, ControlValueAccessor
 
   // Implemented as part of ControlValueAccessor
   registerOnChange(fn: (value: any) => void): void {
-    this._onChange = value => fn(this._locale.parseDate(value));
+    this._onChange = fn;
   }
 
   // Implemented as part of ControlValueAccessor
@@ -139,4 +149,10 @@ export class MdDatepickerInput implements AfterContentInit, ControlValueAccessor
       event.preventDefault();
     }
   }
+
+  _onInput(value: string) {
+    let date = this._locale.parseDate(value);
+    this._onChange(date);
+    this._valueChangeEmitter.emit(date);
+  }
 }

src/lib/datepicker/datepicker.html

@@ -7,6 +7,7 @@
       [minDate]="_minDate"
       [maxDate]="_maxDate"
       [dateFilter]="dateFilter"
-      [(selected)]="_selected">
+      [selected]="_selected"
+      (selectedChange)="_selectAndClose($event)">
   </md-calendar>
 </ng-template>

src/lib/datepicker/datepicker.spec.ts

@@ -117,13 +117,13 @@ describe('MdDatepicker', () => {
       expect(document.querySelector('md-dialog-container')).not.toBeNull();
       expect(testComponent.datepickerInput.value).toEqual(new SimpleDate(2020, 0, 1));
 
-      let selected = new SimpleDate(2017, 0, 1);
-      testComponent.datepicker._selected = selected;
+      let cells = document.querySelectorAll('.mat-calendar-table-cell');
+      dispatchMouseEvent(cells[1], 'click');
       fixture.detectChanges();
 
       fixture.whenStable().then(() => {
         expect(document.querySelector('md-dialog-container')).toBeNull();
-        expect(testComponent.datepickerInput.value).toEqual(selected);
+        expect(testComponent.datepickerInput.value).toEqual(new SimpleDate(2020, 0, 2));
       });
     }));
 
@@ -228,7 +228,7 @@ describe('MdDatepicker', () => {
       expect(testComponent.datepickerInput.value).toBeNull();
 
       let selected = new SimpleDate(2017, 0, 1);
-      testComponent.datepicker._selected = selected;
+      testComponent.datepicker._selectAndClose(selected);
       fixture.detectChanges();
 
       fixture.whenStable().then(() => {
@@ -255,7 +255,7 @@ describe('MdDatepicker', () => {
 
       expect(inputEl.classList).toContain('ng-pristine');
 
-      testComponent.datepicker._selected = new SimpleDate(2017, 0, 1);
+      testComponent.datepicker._selectAndClose(new SimpleDate(2017, 0, 1));
       fixture.detectChanges();
 
       fixture.whenStable().then(() => {
@@ -330,7 +330,7 @@ describe('MdDatepicker', () => {
       expect(testComponent.datepickerInput.value).toBeNull();
 
       let selected = new SimpleDate(2017, 0, 1);
-      testComponent.datepicker._selected = selected;
+      testComponent.datepicker._selectAndClose(selected);
       fixture.detectChanges();
 
       expect(testComponent.formControl.value).toEqual(selected);

src/lib/datepicker/datepicker.ts

@@ -28,6 +28,7 @@ import {SimpleDate} from '../core/datetime/simple-date';
 import {MdDatepickerInput} from './datepicker-input';
 import {CalendarLocale} from '../core/datetime/calendar-locale';
 import 'rxjs/add/operator/first';
+import {Subscription} from 'rxjs/Subscription';
 
 
 /** Used to generate a unique ID for each datepicker instance. */
@@ -81,13 +82,7 @@ export class MdDatepicker implements OnDestroy {
   id = `md-datepicker-${datepickerUid++}`;
 
   /** The currently selected date. */
-  get _selected(): SimpleDate {
-    return this._datepickerInput ? this._datepickerInput.value : null;
-  }
-  set _selected(value: SimpleDate) {
-    this.selectedChanged.emit(value);
-    this.close();
-  }
+  _selected: SimpleDate = null;
 
   /** The minimum selectable date. */
   get _minDate(): SimpleDate {
@@ -114,6 +109,8 @@ export class MdDatepicker implements OnDestroy {
   /** The input element this datepicker is associated with. */
   private _datepickerInput: MdDatepickerInput;
 
+  private _inputSubscription: Subscription;
+
   constructor(private _dialog: MdDialog, private _overlay: Overlay,
               private _viewContainerRef: ViewContainerRef, private _locale: CalendarLocale,
               @Optional() private _dir: Dir) {}
@@ -123,6 +120,19 @@ export class MdDatepicker implements OnDestroy {
     if (this._popupRef) {
       this._popupRef.dispose();
     }
+    if (this._inputSubscription) {
+      this._inputSubscription.unsubscribe();
+    }
+  }
+
+  /** Selects the given date and closes the currently open popup or dialog. */
+  _selectAndClose(date: SimpleDate): void {
+    let oldValue = this._selected;
+    this._selected = date;
+    if (!SimpleDate.equals(oldValue, this._selected)) {
+      this.selectedChanged.emit(date);
+    }
+    this.close();
   }
 
   /**
@@ -134,6 +144,8 @@ export class MdDatepicker implements OnDestroy {
       throw new MdError('An MdDatepicker can only be associated with a single input.');
     }
     this._datepickerInput = input;
+    this._inputSubscription =
+        this._datepickerInput._valueChange.subscribe((value: SimpleDate) => this._selected = value);
   }
 
   /**