fix(animate): ensure transition properties are removed once the animation is over

modules/angular2/src/animate/animation.ts

@@ -34,6 +34,8 @@ export class Animation {
 
   private _stringPrefix: string = '';
 
+  private _temporaryStyles: {[key: string]: string} = {};
+
   /** total amount of time that the animation should take including delay */
   get totalTime(): number {
     let delay = this.computedDelay != null ? this.computedDelay : 0;
@@ -65,10 +67,25 @@ export class Animation {
    */
   setup(): void {
     if (this.data.fromStyles != null) this.applyStyles(this.data.fromStyles);
-    if (this.data.duration != null)
+    if (this.data.duration != null) {
+      this._temporaryStyles['transitionDuration'] = this._readStyle('transitionDuration');
       this.applyStyles({'transitionDuration': this.data.duration.toString() + 'ms'});
-    if (this.data.delay != null)
+    }
+    if (this.data.delay != null) {
+      this._temporaryStyles['transitionDelay'] = this._readStyle('transitionDelay');
       this.applyStyles({'transitionDelay': this.data.delay.toString() + 'ms'});
+    }
+
+    if (!StringMapWrapper.isEmpty(this.data.animationStyles)) {
+      // it's important that we setup a list of the styles and their
+      // initial inline style values prior to applying the animation
+      // styles such that we can restore the values after the animation
+      // has been completed.
+      StringMapWrapper.keys(this.data.animationStyles)
+          .forEach((prop) => { this._temporaryStyles[prop] = this._readStyle(prop); });
+
+      this.applyStyles(this.data.animationStyles);
+    }
   }
 
   /**
@@ -98,12 +115,8 @@ export class Animation {
    */
   applyStyles(styles: {[key: string]: any}): void {
     StringMapWrapper.forEach(styles, (value, key) => {
-      var dashCaseKey = camelCaseToDashCase(key);
-      if (isPresent(DOM.getStyle(this.element, dashCaseKey))) {
-        DOM.setStyle(this.element, dashCaseKey, value.toString());
-      } else {
-        DOM.setStyle(this.element, this._stringPrefix + dashCaseKey, value.toString());
-      }
+      var prop = this._formatStyleProp(key);
+      DOM.setStyle(this.element, prop, value.toString());
     });
   }
 
@@ -123,6 +136,26 @@ export class Animation {
     for (let i = 0, len = classes.length; i < len; i++) DOM.removeClass(this.element, classes[i]);
   }
 
+  private _readStyle(prop: string): string {
+    return DOM.getStyle(this.element, this._formatStyleProp(prop));
+  }
+
+  private _formatStyleProp(prop: string): string {
+    prop = camelCaseToDashCase(prop);
+    return prop.indexOf('animation') >= 0 ? this._stringPrefix + prop : prop;
+  }
+
+  private _removeAndRestoreStyles(styles: {[key: string]: string}): void {
+    StringMapWrapper.forEach(styles, (value, prop) => {
+      prop = this._formatStyleProp(prop);
+      if (value.length > 0) {
+        DOM.setStyle(this.element, prop, value);
+      } else {
+        DOM.removeStyle(this.element, prop);
+      }
+    });
+  }
+
   /**
    * Adds events to track when animations have finished
    */
@@ -147,6 +180,9 @@ export class Animation {
    */
   handleAnimationCompleted(): void {
     this.removeClasses(this.data.animationClasses);
+    this._removeAndRestoreStyles(this._temporaryStyles);
+    this._temporaryStyles = {};
+
     this.callbacks.forEach(callback => callback());
     this.callbacks = [];
     this.eventClearFunctions.forEach(fn => fn());

modules/angular2/src/animate/css_animation_options.ts

@@ -14,6 +14,9 @@ export class CssAnimationOptions {
   /** classes to be added for the duration of the animation */
   animationClasses: string[] = [];
 
+  /** styles to be applied for the duration of the animation */
+  animationStyles: {[key: string]: string} = {};
+
   /** override the duration of the animation (in milliseconds) */
   duration: number;
 

modules/angular2/test/animate/animation_spec.ts

@@ -0,0 +1,133 @@
+import {
+  el,
+  describe,
+  ddescribe,
+  beforeEach,
+  it,
+  iit,
+  expect,
+  inject,
+  SpyObject
+} from 'angular2/testing_internal';
+import {CssAnimationOptions} from 'angular2/src/animate/css_animation_options';
+import {Animation} from 'angular2/src/animate/animation';
+import {BrowserDetails} from 'angular2/src/animate/browser_details';
+import {DOM} from 'angular2/src/platform/dom/dom_adapter';
+
+export function main() {
+  describe("Animation", () => {
+    var element;
+
+    beforeEach(() => { element = el('<div></div>'); });
+
+    describe('transition-duration', () => {
+      it('should only be applied for the duration of the animation', () => {
+        var data = new CssAnimationOptions();
+        data.duration = 1000;
+
+        expect(element).not.toHaveCssStyle('transition-duration');
+
+        new Animation(element, data, new BrowserDetails());
+        expect(element).toHaveCssStyle({'transition-duration': '1000ms'});
+      });
+
+      it('should be removed once the animation is over', () => {
+        var data = new CssAnimationOptions();
+        data.duration = 1000;
+
+        var animation = new Animation(element, data, new BrowserDetails());
+        expect(element).toHaveCssStyle({'transition-duration': '1000ms'});
+
+        animation.handleAnimationCompleted();
+        expect(element).not.toHaveCssStyle('transition-duration');
+      });
+
+      it('should be restore the pre-existing transition-duration once the animation is over if present',
+         () => {
+           DOM.setStyle(element, 'transition-duration', '5s');
+           expect(element).toHaveCssStyle({'transition-duration': '5s'});
+
+           var data = new CssAnimationOptions();
+           data.duration = 1000;
+
+           var animation = new Animation(element, data, new BrowserDetails());
+           expect(element).toHaveCssStyle({'transition-duration': '1000ms'});
+
+           animation.handleAnimationCompleted();
+
+           expect(element).toHaveCssStyle({'transition-duration': '5s'});
+         });
+    });
+
+    describe('transition-delay', () => {
+      it('should only be applied for the delay of the animation', () => {
+        var data = new CssAnimationOptions();
+        data.delay = 1000;
+
+        expect(element).not.toHaveCssStyle('transition-delay');
+
+        new Animation(element, data, new BrowserDetails());
+        expect(element).toHaveCssStyle({'transition-delay': '1000ms'});
+      });
+
+      it('should be removed once the animation is over', () => {
+        var data = new CssAnimationOptions();
+        data.delay = 1000;
+
+        var animation = new Animation(element, data, new BrowserDetails());
+        expect(element).toHaveCssStyle({'transition-delay': '1000ms'});
+
+        animation.handleAnimationCompleted();
+        expect(element).not.toHaveCssStyle('transition-delay');
+      });
+
+      it('should be restore the pre-existing transition-delay once the animation is over if present',
+         () => {
+           DOM.setStyle(element, 'transition-delay', '5s');
+           expect(element).toHaveCssStyle({'transition-delay': '5s'});
+
+           var data = new CssAnimationOptions();
+           data.delay = 1000;
+
+           var animation = new Animation(element, data, new BrowserDetails());
+           expect(element).toHaveCssStyle({'transition-delay': '1000ms'});
+
+           animation.handleAnimationCompleted();
+
+           expect(element).toHaveCssStyle({'transition-delay': '5s'});
+         });
+    });
+
+    describe('temporary animation styles', () => {
+      it('should be applied temporarily for the duration of the animation', () => {
+        var data = new CssAnimationOptions();
+        data.duration = 1000;
+        data.animationStyles = {'width': '100px', 'opacity': '0.5'};
+
+        var animation = new Animation(element, data, new BrowserDetails());
+        expect(element)
+            .toHaveCssStyle({'opacity': '0.5', 'width': '100px', 'transition-duration': '1000ms'});
+
+        animation.handleAnimationCompleted();
+        expect(element).not.toHaveCssStyle('width');
+        expect(element).not.toHaveCssStyle('opacity');
+        expect(element).not.toHaveCssStyle('transition-duration');
+      });
+
+      it('should be restored back to the original styles on the element', () => {
+        DOM.setStyle(element, 'height', '555px');
+
+        var data = new CssAnimationOptions();
+        data.duration = 1000;
+        data.animationStyles = {'width': '100px', 'height': '999px'};
+
+        var animation = new Animation(element, data, new BrowserDetails());
+        expect(element).toHaveCssStyle({'width': '100px', 'height': '999px'});
+
+        animation.handleAnimationCompleted();
+        expect(element).not.toHaveCssStyle('width');
+        expect(element).toHaveCssStyle({'height': '555px'});
+      });
+    });
+  });
+}