Change API to accept string values

src/demo-app/input/input-container-demo.html

@@ -180,10 +180,16 @@ <h4>Textarea</h4>
       </md-input-container>
     </p>
     <p>
-      <md-checkbox [(ngModel)]="floatingLabel">Toggle Floating Label</md-checkbox>
-      <button md-button (click)="floatingLabel = null">Reset Floating Label</button>
+      <md-button-toggle-group [(ngModel)]="floatingLabel">
+        <md-button-toggle value="auto">Auto Float</md-button-toggle>
+        <md-button-toggle value="always">Always Float</md-button-toggle>
+        <md-button-toggle value="never">Never Float</md-button-toggle>
+      </md-button-toggle-group>
+    </p>
+
+    <p>
       <md-input-container [floatingPlaceholder]="floatingLabel">
-        <input mdInput [placeholder]="floatingLabel ? 'Floating label' : 'Not floating label'">
+        <input mdInput placeholder="Placeholder">
       </md-input-container>
     </p>
 

src/demo-app/input/input-container-demo.ts

@@ -11,9 +11,9 @@ let max = 5;
   styleUrls: ['input-demo.css'],
 })
 export class InputContainerDemo {
+  floatingLabel: string = 'auto';
   dividerColor: boolean;
   requiredField: boolean;
-  floatingLabel: boolean;
   ctrlDisabled = false;
 
   name: string;

src/lib/input/OVERVIEW.md

@@ -38,9 +38,11 @@ be used with `md-input-container`:
 A placeholder is an indicative text displayed in the input zone when the input does not contain
 text. When text is present, the indicative text will float above this input zone.
 
-The `floatingPlaceholder` attribute of `md-input-container` can be set to `false` to hide the
+The `floatingPlaceholder` attribute of `md-input-container` can be set to `never` to hide the
 indicative text instead when text is present in the input.
 
+When setting `floatingPlaceholder` to `always` the floating label will always show above the input.
+
 A placeholder for the input can be specified in one of two ways: either using the `placeholder`
 attribute on the `input` or `textarea`, or using an `md-placeholder` element in the
 `md-input-container`. Using both will raise an error.

src/lib/input/input-container-errors.ts

@@ -28,3 +28,9 @@ export class MdInputContainerMissingMdInputError extends MdError {
           'to the native input or textarea element?');
   }
 }
+
+export class MdInputContainerFloatingPlaceholderInvalidError extends MdError {
+  constructor(value: string) {
+    super(`The value "${value}" for the floatingPlaceholder input is not valid.`);
+  }
+}

src/lib/input/input-container.html

@@ -9,7 +9,7 @@
              [attr.for]="_mdInputChild.id"
              [class.md-empty]="_mdInputChild.empty && !_shouldAlwaysFloat"
              [class.md-focused]="_mdInputChild.focused"
-             [class.md-float]="floatingPlaceholder"
+             [class.md-float]="_canPlaceholderFloat"
              [class.md-accent]="dividerColor == 'accent'"
              [class.md-warn]="dividerColor == 'warn'"
              *ngIf="_hasPlaceholder()">

src/lib/input/input-container.spec.ts

@@ -60,8 +60,8 @@ describe('MdInputContainer', function () {
 
     let inputContainer = fixture.debugElement.query(By.directive(MdInputContainer))
         .componentInstance as MdInputContainer;
-    expect(inputContainer.floatingPlaceholder).toBe(true,
-        'Expected MdInputContainer to default to having floating placeholders turned on');
+    expect(inputContainer.floatingPlaceholder).toBe('auto',
+        'Expected MdInputContainer to set floatingLabel to auto by default.');
   });
 
   it('should not be treated as empty if type is date',
@@ -410,20 +410,20 @@ describe('MdInputContainer', function () {
     let fixture = TestBed.createComponent(MdInputContainerWithDynamicPlaceholder);
     fixture.detectChanges();
 
-    let inputEl = fixture.debugElement.query(By.css('input'));
+    let inputEl = fixture.debugElement.query(By.css('input')).nativeElement;
     let labelEl = fixture.debugElement.query(By.css('label')).nativeElement;
 
     expect(labelEl.classList).not.toContain('md-empty');
     expect(labelEl.classList).toContain('md-float');
 
-    fixture.componentInstance.shouldFloat = null;
+    fixture.componentInstance.shouldFloat = 'auto';
     fixture.detectChanges();
 
     expect(labelEl.classList).toContain('md-empty');
     expect(labelEl.classList).toContain('md-float');
 
     // Update the value of the input.
-    inputEl.nativeElement.value = 'Text';
+    inputEl.value = 'Text';
 
     // Fake behavior of the `(input)` event which should trigger a change detection.
     fixture.detectChanges();
@@ -436,7 +436,7 @@ describe('MdInputContainer', function () {
     let fixture = TestBed.createComponent(MdInputContainerWithDynamicPlaceholder);
     fixture.detectChanges();
 
-    let inputEl = fixture.debugElement.query(By.css('input'));
+    let inputEl = fixture.debugElement.query(By.css('input')).nativeElement;
     let labelEl = fixture.debugElement.query(By.css('label')).nativeElement;
 
     expect(labelEl.classList).not.toContain('md-empty');
@@ -445,7 +445,7 @@ describe('MdInputContainer', function () {
     fixture.detectChanges();
 
     // Update the value of the input.
-    inputEl.nativeElement.value = 'Text';
+    inputEl.value = 'Text';
 
     // Fake behavior of the `(input)` event which should trigger a change detection.
     fixture.detectChanges();
@@ -458,17 +458,17 @@ describe('MdInputContainer', function () {
   it('should never float the placeholder when floatingPlaceholder is set to false', () => {
     let fixture = TestBed.createComponent(MdInputContainerWithDynamicPlaceholder);
 
-    fixture.componentInstance.shouldFloat = false;
+    fixture.componentInstance.shouldFloat = 'never';
     fixture.detectChanges();
 
-    let inputEl = fixture.debugElement.query(By.css('input'));
+    let inputEl = fixture.debugElement.query(By.css('input')).nativeElement;
     let labelEl = fixture.debugElement.query(By.css('label')).nativeElement;
 
     expect(labelEl.classList).toContain('md-empty');
     expect(labelEl.classList).not.toContain('md-float');
 
     // Update the value of the input.
-    inputEl.nativeElement.value = 'Text';
+    inputEl.value = 'Text';
 
     // Fake behavior of the `(input)` event which should trigger a change detection.
     fixture.detectChanges();
@@ -646,7 +646,7 @@ class MdInputContainerWithValueBinding {
 
 @Component({
   template: `
-    <md-input-container [floatingPlaceholder]="false">
+    <md-input-container floatingPlaceholder="never">
       <input md-input placeholder="Label">
     </md-input-container>
   `
@@ -660,7 +660,7 @@ class MdInputContainerWithStaticPlaceholder {}
     </md-input-container>`
 })
 class MdInputContainerWithDynamicPlaceholder {
-  shouldFloat: boolean = true;
+  shouldFloat: string = 'always';
 }
 
 @Component({

src/lib/input/input-container.ts

@@ -20,7 +20,7 @@ import {
   MdInputContainerUnsupportedTypeError,
   MdInputContainerPlaceholderConflictError,
   MdInputContainerDuplicatedHintError,
-  MdInputContainerMissingMdInputError
+  MdInputContainerMissingMdInputError, MdInputContainerFloatingPlaceholderInvalidError
 } from './input-container-errors';
 
 
@@ -38,6 +38,9 @@ const MD_INPUT_INVALID_TYPES = [
   'submit'
 ];
 
+/** Valid options for the floatingPlaceholder input binding. */
+export type MD_INPUT_PLACEHOLDER_TYPES = 'always' | 'never' | 'auto';
+const MD_INPUT_PLACEHOLDER_VALUES = ['always', 'never', 'auto'];
 
 let nextUniqueId = 0;
 
@@ -249,11 +252,10 @@ export class MdInputContainer implements AfterContentInit {
   @Input() dividerColor: 'primary' | 'accent' | 'warn' = 'primary';
 
   /** Whether the floating label should always float or not. */
-  _shouldAlwaysFloat: boolean = false;
+  get _shouldAlwaysFloat() { return this._floatingPlaceholder === 'always'; };
 
   /** Whether the placeholder can float or not. */
-  _floatingPlaceholder: boolean = true;
-
+  get _canPlaceholderFloat() { return this._floatingPlaceholder !== 'never'; }
 
   /** Text for the input hint. */
   @Input()
@@ -265,15 +267,17 @@ export class MdInputContainer implements AfterContentInit {
   private _hintLabel = '';
 
   /**
-   * Whether the placeholder should always float or just show the placeholder when empty.
-   * If the value is set to null the placeholder will float if text is entered.
+   * Whether the placeholder should always float, never float or float as the user types.
    */
   @Input()
   get floatingPlaceholder() { return this._floatingPlaceholder; }
-  set floatingPlaceholder(value: boolean) {
-    this._floatingPlaceholder = value == null || coerceBooleanProperty(value);
-    this._shouldAlwaysFloat = coerceBooleanProperty(value);
+  set floatingPlaceholder(value: MD_INPUT_PLACEHOLDER_TYPES) {
+    if (value && MD_INPUT_PLACEHOLDER_VALUES.indexOf(value) === -1) {
+      throw new MdInputContainerFloatingPlaceholderInvalidError(value);
+    }
+    this._floatingPlaceholder = value || 'auto';
   }
+  private _floatingPlaceholder: MD_INPUT_PLACEHOLDER_TYPES = 'auto';
 
   @ContentChild(MdInputDirective) _mdInputChild: MdInputDirective;