feat(datepicker): add theming support

Adds support for theming the datepicker using the `color` attribute, as well as inheriting the theme color from the form field around a datepicker input.

Author: crisbeto

src/demo-app/datepicker/datepicker-demo.html

@@ -5,6 +5,13 @@ <h2>Options</h2>
   <mat-checkbox [(ngModel)]="yearView">Start in year view</mat-checkbox>
   <mat-checkbox [(ngModel)]="datepickerDisabled">Disable datepicker</mat-checkbox>
   <mat-checkbox [(ngModel)]="inputDisabled">Disable input</mat-checkbox>
+  <mat-form-field>
+    <mat-select [(ngModel)]="color" placeholder="Color">
+      <mat-option value="primary">Primary</mat-option>
+      <mat-option value="accent">Accent</mat-option>
+      <mat-option value="warn">Warn</mat-option>
+    </mat-select>
+  </mat-form-field>
 </p>
 <p>
   <mat-form-field>
@@ -53,7 +60,8 @@ <h2>Result</h2>
         [touchUi]="touch"
         [disabled]="datepickerDisabled"
         [startAt]="startAt"
-        [startView]="yearView ? 'year' : 'month'">
+        [startView]="yearView ? 'year' : 'month'"
+        [color]="color">
     </mat-datepicker>
     <mat-error *ngIf="resultPickerModel.hasError('matDatepickerParse')">
       "{{resultPickerModel.getError('matDatepickerParse').text}}" is not a valid date!

src/demo-app/datepicker/datepicker-demo.ts

@@ -8,7 +8,9 @@
 
 import {ChangeDetectionStrategy, Component} from '@angular/core';
 import {FormControl} from '@angular/forms';
-import {MatDatepickerInputEvent} from '@angular/material';
+import {MatDatepickerInputEvent} from '@angular/material/datepicker';
+import {ThemePalette} from '@angular/material/core';
+
 
 @Component({
   moduleId: module.id,
@@ -29,6 +31,7 @@ export class DatepickerDemo {
   date: Date;
   lastDateInput: Date | null;
   lastDateChange: Date | null;
+  color: ThemePalette;
 
   dateCtrl = new FormControl();
 

src/lib/datepicker/_datepicker-theme.scss

@@ -3,24 +3,32 @@
 @import '../core/typography/typography-utils';
 
 
+$mat-datepicker-selected-today-box-shadow-width: 1px;
+$mat-datepicker-selected-fade-amount: 0.6;
+$mat-datepicker-today-fade-amount: 0.2;
 $mat-calendar-body-font-size: 13px !default;
 $mat-calendar-weekday-table-font-size: 11px !default;
 
+@mixin _mat-datepicker-color($palette) {
+  .mat-calendar-body-selected {
+    background-color: mat-color($palette);
+    color: mat-color($palette, default-contrast);
+  }
+
+  .mat-calendar-body-disabled > .mat-calendar-body-selected {
+    background-color: fade-out(mat-color($palette), $mat-datepicker-selected-fade-amount);
+  }
+
+  .mat-calendar-body-today.mat-calendar-body-selected {
+    box-shadow: inset 0 0 0 $mat-datepicker-selected-today-box-shadow-width
+                mat-color($palette, default-contrast);
+  }
+}
 
 @mixin mat-datepicker-theme($theme) {
-  $primary: map-get($theme, primary);
   $foreground: map-get($theme, foreground);
   $background: map-get($theme, background);
 
-  $mat-datepicker-selected-today-box-shadow-width: 1px;
-  $mat-datepicker-selected-fade-amount: 0.6;
-  $mat-datepicker-today-fade-amount: 0.2;
-
-  .mat-datepicker-content {
-    background-color: mat-color($background, card);
-    color: mat-color($foreground, text);
-  }
-
   .mat-calendar-arrow {
     border-top-color: mat-color($foreground, icon);
   }
@@ -59,34 +67,41 @@ $mat-calendar-weekday-table-font-size: 11px !default;
     }
   }
 
-  .mat-calendar-body-selected {
-    background-color: mat-color($primary);
-    color: mat-color($primary, default-contrast);
+  .mat-calendar-body-today:not(.mat-calendar-body-selected) {
+    // Note: though it's not text, the border is a hint about the fact that this is today's date,
+    // so we use the hint color.
+    border-color: mat-color($foreground, hint-text);
   }
 
-  .mat-calendar-body-disabled > .mat-calendar-body-selected {
-    background-color: fade-out(mat-color($primary), $mat-datepicker-selected-fade-amount);
+  .mat-calendar-body-disabled > .mat-calendar-body-today:not(.mat-calendar-body-selected) {
+    border-color: fade-out(mat-color($foreground, hint-text), $mat-datepicker-today-fade-amount);
   }
 
-  .mat-calendar-body-today {
-    &:not(.mat-calendar-body-selected) {
-      // Note: though it's not text, the border is a hint about the fact that this is today's date,
-      // so we use the hint color.
-      border-color: mat-color($foreground, hint-text);
-    }
+  @include _mat-datepicker-color(map-get($theme, primary));
+
+  .mat-datepicker-content {
+    background-color: mat-color($background, card);
+    color: mat-color($foreground, text);
 
-    &.mat-calendar-body-selected {
-      box-shadow: inset 0 0 0 $mat-datepicker-selected-today-box-shadow-width
-                  mat-color($primary, default-contrast);
+    &.mat-accent {
+      @include _mat-datepicker-color(map-get($theme, accent));
     }
-  }
 
-  .mat-calendar-body-disabled > .mat-calendar-body-today:not(.mat-calendar-body-selected) {
-    border-color: fade-out(mat-color($foreground, hint-text), $mat-datepicker-today-fade-amount);
+    &.mat-warn {
+      @include _mat-datepicker-color(map-get($theme, warn));
+    }
   }
 
   .mat-datepicker-toggle-active {
-    color: mat-color($primary);
+    color: mat-color(map-get($theme, primary));
+
+    &.mat-accent {
+      color: mat-color(map-get($theme, accent));
+    }
+
+    &.mat-warn {
+      color: mat-color(map-get($theme, warn));
+    }
   }
 }
 

src/lib/datepicker/datepicker-input.ts

@@ -334,6 +334,11 @@ export class MatDatepickerInput<D> implements AfterContentInit, ControlValueAcce
     this.dateChange.emit(new MatDatepickerInputEvent(this, this._elementRef.nativeElement));
   }
 
+  /** Returns the palette used by the input's form field, if any. */
+  _getThemePalette() {
+    return this._formField ? this._formField.color : undefined;
+  }
+
   /**
    * @param obj The object to check.
    * @returns The given object if it is both a date instance and valid, otherwise null.

src/lib/datepicker/datepicker-toggle.ts

@@ -42,6 +42,8 @@ export class MatDatepickerToggleIcon {}
   host: {
     'class': 'mat-datepicker-toggle',
     '[class.mat-datepicker-toggle-active]': 'datepicker && datepicker.opened',
+    '[class.mat-accent]': 'datepicker && datepicker.color === "accent"',
+    '[class.mat-warn]': 'datepicker && datepicker.color === "warn"',
   },
   exportAs: 'matDatepickerToggle',
   encapsulation: ViewEncapsulation.None,

src/lib/datepicker/datepicker.spec.ts

@@ -14,7 +14,7 @@ import {
   NativeDateModule,
   SEP,
 } from '@angular/material/core';
-import {MatFormFieldModule} from '@angular/material/form-field';
+import {MatFormFieldModule, MatFormField} from '@angular/material/form-field';
 import {By} from '@angular/platform-browser';
 import {NoopAnimationsModule} from '@angular/platform-browser/animations';
 import {MatInputModule} from '../input/index';
@@ -98,6 +98,29 @@ describe('MatDatepicker', () => {
             .not.toBeNull();
       });
 
+      it('should pass the datepicker theme color to the overlay', fakeAsync(() => {
+        testComponent.datepicker.color = 'primary';
+        testComponent.datepicker.open();
+        fixture.detectChanges();
+
+        let contentEl = document.querySelector('.mat-datepicker-content')!;
+
+        expect(contentEl.classList).toContain('mat-primary');
+
+        testComponent.datepicker.close();
+        fixture.detectChanges();
+        flush();
+
+        testComponent.datepicker.color = 'warn';
+        testComponent.datepicker.open();
+
+        contentEl = document.querySelector('.mat-datepicker-content')!;
+        fixture.detectChanges();
+
+        expect(contentEl.classList).toContain('mat-warn');
+        expect(contentEl.classList).not.toContain('mat-primary');
+      }));
+
       it('should open datepicker if opened input is set to true', () => {
         testComponent.opened = true;
         fixture.detectChanges();
@@ -137,19 +160,21 @@ describe('MatDatepicker', () => {
         expect(document.querySelector('.cdk-overlay-pane')).not.toBeNull();
       });
 
-      it('close should close popup', () => {
+      it('close should close popup', fakeAsync(() => {
         testComponent.datepicker.open();
         fixture.detectChanges();
+        flush();
 
         let popup = document.querySelector('.cdk-overlay-pane')!;
         expect(popup).not.toBeNull();
         expect(parseInt(getComputedStyle(popup).height as string)).not.toBe(0);
 
         testComponent.datepicker.close();
         fixture.detectChanges();
+        flush();
 
         expect(parseInt(getComputedStyle(popup).height as string)).toBe(0);
-      });
+      }));
 
       it('should close the popup when pressing ESCAPE', fakeAsync(() => {
         testComponent.datepicker.open();
@@ -848,13 +873,13 @@ describe('MatDatepicker', () => {
       beforeEach(fakeAsync(() => {
         fixture = createComponent(FormFieldDatepicker, [MatNativeDateModule]);
         fixture.detectChanges();
-
         testComponent = fixture.componentInstance;
       }));
 
       afterEach(fakeAsync(() => {
         testComponent.datepicker.close();
         fixture.detectChanges();
+        flush();
       }));
 
       it('should float the placeholder when an invalid value is entered', () => {
@@ -865,6 +890,41 @@ describe('MatDatepicker', () => {
         expect(fixture.debugElement.nativeElement.querySelector('mat-form-field').classList)
           .toContain('mat-form-field-should-float');
       });
+
+      it('should pass the form field theme color to the overlay', fakeAsync(() => {
+        testComponent.formField.color = 'primary';
+        testComponent.datepicker.open();
+        fixture.detectChanges();
+
+        let contentEl = document.querySelector('.mat-datepicker-content')!;
+
+        expect(contentEl.classList).toContain('mat-primary');
+
+        testComponent.datepicker.close();
+        fixture.detectChanges();
+        flush();
+
+        testComponent.formField.color = 'warn';
+        testComponent.datepicker.open();
+
+        contentEl = document.querySelector('.mat-datepicker-content')!;
+        fixture.detectChanges();
+
+        expect(contentEl.classList).toContain('mat-warn');
+        expect(contentEl.classList).not.toContain('mat-primary');
+      }));
+
+      it('should prefer the datepicker color over the form field one', fakeAsync(() => {
+        testComponent.datepicker.color = 'accent';
+        testComponent.formField.color = 'warn';
+        testComponent.datepicker.open();
+        fixture.detectChanges();
+
+        const contentEl = document.querySelector('.mat-datepicker-content')!;
+
+        expect(contentEl.classList).toContain('mat-accent');
+        expect(contentEl.classList).not.toContain('mat-warn');
+      }));
     });
 
     describe('datepicker with min and max dates and validation', () => {
@@ -1423,6 +1483,7 @@ class DatepickerWithCustomIcon {}
 class FormFieldDatepicker {
   @ViewChild('d') datepicker: MatDatepicker<Date>;
   @ViewChild(MatDatepickerInput) datepickerInput: MatDatepickerInput<Date>;
+  @ViewChild(MatFormField) formField: MatFormField;
 }