feat(stepper): Merge initial prototype of stepper into the upstream s…

…tepper branch. (angular#5742)

* Prototyping

* Further work

* Further prototyping

* Further prototyping

* Further work

* Adding event emitters

* Adding "selectedIndex" attribute to stepper and working on TemplateOulet.

* Prototyping

* Further work

* Further prototyping

* Further prototyping

* Further work

* Adding event emitters

* Template rendering and selectIndex control done.

* Work in progress for accessibility

* Added functionalities based on the tentative API doc.

* Refactor code for cdk-stepper and cdk-step

* Add support for templated label

* Added support for keyboard events and focus changes for accessibility.

* Updated vertical stepper + added comments

* Fix package-lock.json

* Fix indention

* Changes made based on the review

* Changes based on review - event properties, selectors, SPACE support, etc. + demo

* Add select() for step component + refactor to avoid circular dependency + support cycling using arrow keys

* API change based on review

* Minor code clean up based on review.

* Several name changes, etc based on review

* Add to compatibility mode list and refactor to avoid circular dependency

src/cdk/stepper/index.ts

@@ -0,0 +1,22 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import {NgModule} from '@angular/core';
+import {CdkStepper, CdkStep} from './stepper';
+import {CommonModule} from '@angular/common';
+import {CdkStepLabel} from './step-label';
+
+@NgModule({
+  imports: [CommonModule],
+  exports: [CdkStep, CdkStepper, CdkStepLabel],
+  declarations: [CdkStep, CdkStepper, CdkStepLabel]
+})
+export class CdkStepperModule {}
+
+export * from './stepper';
+export * from './step-label';

src/cdk/stepper/step-label.ts

@@ -0,0 +1,16 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import {Directive, TemplateRef} from '@angular/core';
+
+@Directive({
+  selector: '[cdkStepLabel]',
+})
+export class CdkStepLabel {
+  constructor(public template: TemplateRef<any>) { }
+}

src/cdk/stepper/step.html

@@ -0,0 +1 @@
+<ng-template><ng-content></ng-content></ng-template>

src/cdk/stepper/stepper.ts

@@ -0,0 +1,169 @@
+/**
+ * @license
+ * Copyright Google Inc. All Rights Reserved.
+ *
+ * Use of this source code is governed by an MIT-style license that can be
+ * found in the LICENSE file at https://angular.io/license
+ */
+
+import {
+  ContentChildren,
+  EventEmitter,
+  Input,
+  Output,
+  QueryList,
+  Directive,
+  // This import is only used to define a generic type. The current TypeScript version incorrectly
+  // considers such imports as unused (https://github.com/Microsoft/TypeScript/issues/14953)
+  // tslint:disable-next-line:no-unused-variable
+  ElementRef,
+  Component,
+  ContentChild,
+  ViewChild,
+  TemplateRef
+} from '@angular/core';
+import {LEFT_ARROW, RIGHT_ARROW, ENTER, SPACE} from '../keyboard/keycodes';
+import {CdkStepLabel} from './step-label';
+
+/** Used to generate unique ID for each stepper component. */
+let nextId = 0;
+
+/** Change event emitted on selection changes. */
+export class CdkStepperSelectionEvent {
+  /** Index of the step now selected. */
+  selectedIndex: number;
+
+  /** Index of the step previously selected. */
+  previouslySelectedIndex: number;
+
+  /** The step instance now selected. */
+  selectedStep: CdkStep;
+
+  /** The step instance previously selected. */
+  previouslySelectedStep: CdkStep;
+}
+
+@Component({
+  selector: 'cdk-step',
+  templateUrl: 'step.html',
+})
+export class CdkStep {
+  /** Template for step label if it exists. */
+  @ContentChild(CdkStepLabel) stepLabel: CdkStepLabel;
+
+  /** Template for step content. */
+  @ViewChild(TemplateRef) content: TemplateRef<any>;
+
+  /** Label of the step. */
+  @Input()
+  label: string;
+
+  constructor(private _stepper: CdkStepper) { }
+
+  /** Selects this step component. */
+  select(): void {
+    this._stepper.selected = this;
+  }
+}
+
+@Directive({
+  selector: 'cdk-stepper',
+  host: {
+    '(focus)': '_focusStep()',
+    '(keydown)': '_onKeydown($event)',
+  },
+})
+export class CdkStepper {
+  /** The list of step components that the stepper is holding. */
+  @ContentChildren(CdkStep) _steps: QueryList<CdkStep>;
+
+  /** The list of step headers of the steps in the stepper. */
+  _stepHeader: QueryList<ElementRef>;
+
+  /** The index of the selected step. */
+  @Input()
+  get selectedIndex() { return this._selectedIndex; }
+  set selectedIndex(index: number) {
+    if (this._selectedIndex != index) {
+      this._emitStepperSelectionEvent(index);
+      this._focusStep(this._selectedIndex);
+    }
+  }
+  private _selectedIndex: number = 0;
+
+  /** The step that is selected. */
+  @Input()
+  get selected() { return this._steps[this.selectedIndex]; }
+  set selected(step: CdkStep) {
+    let index = this._steps.toArray().indexOf(step);
+    this.selectedIndex = index;
+  }
+
+  /** Event emitted when the selected step has changed. */
+  @Output() selectionChange = new EventEmitter<CdkStepperSelectionEvent>();
+
+  /** The index of the step that the focus can be set. */
+  _focusIndex: number = 0;
+
+  /** Used to track unique ID for each stepper component. */
+  private _groupId: number;
+
+  constructor() {
+    this._groupId = nextId++;
+  }
+
+  /** Selects and focuses the next step in list. */
+  next(): void {
+    this.selectedIndex = Math.min(this._selectedIndex + 1, this._steps.length - 1);
+  }
+
+  /** Selects and focuses the previous step in list. */
+  previous(): void {
+    this.selectedIndex = Math.max(this._selectedIndex - 1, 0);
+  }
+
+  /** Returns a unique id for each step label element. */
+  _getStepLabelId(i: number): string {
+    return `mat-step-label-${this._groupId}-${i}`;
+  }
+
+  /** Returns nique id for each step content element. */
+  _getStepContentId(i: number): string {
+    return `mat-step-content-${this._groupId}-${i}`;
+  }
+
+  private _emitStepperSelectionEvent(newIndex: number): void {
+    const stepsArray = this._steps.toArray();
+    this.selectionChange.emit({
+      selectedIndex: newIndex,
+      previouslySelectedIndex: this._selectedIndex,
+      selectedStep: stepsArray[newIndex],
+      previouslySelectedStep: stepsArray[this._selectedIndex],
+    });
+    this._selectedIndex = newIndex;
+  }
+
+  _onKeydown(event: KeyboardEvent) {
+    switch (event.keyCode) {
+      case RIGHT_ARROW:
+        this._focusStep((this._focusIndex + 1) % this._steps.length);
+        break;
+      case LEFT_ARROW:
+        this._focusStep((this._focusIndex + this._steps.length - 1) % this._steps.length);
+        break;
+      case SPACE:
+      case ENTER:
+        this._emitStepperSelectionEvent(this._focusIndex);
+        break;
+      default:
+        // Return to avoid calling preventDefault on keys that are not explicitly handled.
+        return;
+    }
+    event.preventDefault();
+  }
+
+  private _focusStep(index: number) {
+    this._focusIndex = index;
+    this._stepHeader.toArray()[this._focusIndex].nativeElement.focus();
+  }
+}

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

@@ -72,6 +72,7 @@ export class DemoApp {
     {name: 'Slider', route: '/slider'},
     {name: 'Slide Toggle', route: '/slide-toggle'},
     {name: 'Snack Bar', route: '/snack-bar'},
+    {name: 'Stepper', route: 'stepper'},
     {name: 'Table', route: '/table'},
     {name: 'Tabs', route: '/tabs'},
     {name: 'Toolbar', route: '/toolbar'},

src/demo-app/demo-app/routes.ts

@@ -36,6 +36,7 @@ import {DatepickerDemo} from '../datepicker/datepicker-demo';
 import {TableDemo} from '../table/table-demo';
 import {TypographyDemo} from '../typography/typography-demo';
 import {ExpansionDemo} from '../expansion/expansion-demo';
+import {StepperDemo} from '../stepper/stepper-demo';
 import {DemoApp} from './demo-app';
 import {AccessibilityDemo} from '../a11y/a11y';
 import {ACCESSIBILITY_DEMO_ROUTES} from '../a11y/routes';
@@ -78,6 +79,7 @@ export const DEMO_APP_ROUTES: Routes = [
     {path: 'style', component: StyleDemo},
     {path: 'typography', component: TypographyDemo},
     {path: 'expansion', component: ExpansionDemo},
+    {path: 'stepper', component: StepperDemo}
   ]}
 ];
 

src/demo-app/stepper/stepper-demo.html

@@ -0,0 +1,27 @@
+<h2>Horizontal Stepper Demo</h2>
+<md-horizontal-stepper>
+  <md-step *ngFor="let step of steps" [label]="step.label">
+    <md-input-container>
+      <input mdInput placeholder="Answer" [(ngModel)]="step.content">
+    </md-input-container>
+  </md-step>
+</md-horizontal-stepper>
+
+<h2>Horizontal Stepper Demo with Templated Label</h2>
+<md-horizontal-stepper>
+  <md-step *ngFor="let step of steps">
+    <ng-template mdStepLabel>{{step.label}}</ng-template>
+    <md-input-container>
+      <input mdInput placeholder="Answer" [(ngModel)]="step.content">
+    </md-input-container>
+  </md-step>
+</md-horizontal-stepper>
+
+<h2>Vertical Stepper Demo</h2>
+<md-vertical-stepper>
+  <md-step *ngFor="let step of steps" [label]="step.label">
+    <md-input-container>
+      <input mdInput placeholder="Answer" [(ngModel)]="step.content">
+    </md-input-container>
+  </md-step>
+</md-vertical-stepper>

src/demo-app/stepper/stepper-demo.ts

@@ -0,0 +1,16 @@
+import {Component} from '@angular/core';
+
+@Component({
+  moduleId: module.id,
+  selector: 'stepper-demo',
+  templateUrl: 'stepper-demo.html',
+  styleUrls: ['stepper-demo.scss'],
+})
+export class StepperDemo {
+  steps = [
+    {label: 'Confirm your name', content: 'Last name, First name.'},
+    {label: 'Confirm your contact information', content: '123-456-7890'},
+    {label: 'Confirm your address', content: '1600 Amphitheater Pkwy MTV'},
+    {label: 'You are now done', content: 'Finished!'}
+  ];
+}

src/lib/core/compatibility/compatibility.ts

@@ -39,6 +39,7 @@ export const MAT_ELEMENTS_SELECTOR = `
   [matHeaderRowDef],
   [matLine],
   [matRowDef],
+  [matStepLabel],
   [matTabLabel],
   [matTabLink],
   [matTabNav],
@@ -73,6 +74,7 @@ export const MAT_ELEMENTS_SELECTOR = `
   mat-header-cell,
   mat-header-row,
   mat-hint,
+  mat-horizontal-stepper,
   mat-icon,
   mat-input-container,
   mat-form-field,
@@ -92,10 +94,12 @@ export const MAT_ELEMENTS_SELECTOR = `
   mat-sidenav-container,
   mat-slider,
   mat-spinner,
+  mat-step,
   mat-tab,
   mat-table,
   mat-tab-group,
-  mat-toolbar`;
+  mat-toolbar,
+  mat-vertical-stepper`;
 
 /** Selector that matches all elements that may have style collisions with AngularJS Material. */
 export const MD_ELEMENTS_SELECTOR = `
@@ -116,6 +120,7 @@ export const MD_ELEMENTS_SELECTOR = `
   [mdHeaderRowDef],
   [mdLine],
   [mdRowDef],
+  [mdStepLabel],
   [mdTabLabel],
   [mdTabLink],
   [mdTabNav],
@@ -150,6 +155,7 @@ export const MD_ELEMENTS_SELECTOR = `
   md-header-cell,
   md-header-row,
   md-hint,
+  md-horizontal-stepper,
   md-icon,
   md-input-container,
   md-form-field,
@@ -169,10 +175,12 @@ export const MD_ELEMENTS_SELECTOR = `
   md-sidenav-container,
   md-slider,
   md-spinner,
+  md-step,
   md-tab,
   md-table,
   md-tab-group,
-  md-toolbar`;
+  md-toolbar,
+  md-vertical-stepper`;
 
 /** Directive that enforces that the `mat-` prefix cannot be used. */
 @Directive({selector: MAT_ELEMENTS_SELECTOR})

src/lib/module.ts

@@ -46,6 +46,7 @@ import {MdTableModule} from './table/index';
 import {MdSortModule} from './sort/index';
 import {MdPaginatorModule} from './paginator/index';
 import {MdFormFieldModule} from './form-field/index';
+import {MdStepperModule} from './stepper/index';
 
 const MATERIAL_MODULES = [
   MdAutocompleteModule,
@@ -75,6 +76,7 @@ const MATERIAL_MODULES = [
   MdSlideToggleModule,
   MdSnackBarModule,
   MdSortModule,
+  MdStepperModule,
   MdTabsModule,
   MdToolbarModule,
   MdTooltipModule,
@@ -85,7 +87,7 @@ const MATERIAL_MODULES = [
   A11yModule,
   PlatformModule,
   MdCommonModule,
-  ObserversModule
+  ObserversModule,
 ];
 
 /** @deprecated */

src/lib/public_api.ts

@@ -46,3 +46,4 @@ export * from './tabs/index';
 export * from './tabs/tab-nav-bar/index';
 export * from './toolbar/index';
 export * from './tooltip/index';
+export * from './stepper/index';