Added animation when modal backdrop is static

js/src/modal.js

@@ -50,6 +50,7 @@ const DefaultType = {
 
 const Event = {
   HIDE: `hide${EVENT_KEY}`,
+  HIDE_PREVENTED: `hidePrevented${EVENT_KEY}`,
   HIDDEN: `hidden${EVENT_KEY}`,
   SHOW: `show${EVENT_KEY}`,
   SHOWN: `shown${EVENT_KEY}`,
@@ -68,7 +69,8 @@ const ClassName = {
   BACKDROP: 'modal-backdrop',
   OPEN: 'modal-open',
   FADE: 'fade',
-  SHOW: 'show'
+  SHOW: 'show',
+  STATIC: 'modal-static'
 }
 
 const Selector = {
@@ -307,8 +309,8 @@ class Modal {
     if (this._isShown && this._config.keyboard) {
       EventHandler.on(this._element, Event.KEYDOWN_DISMISS, event => {
         if (event.which === ESCAPE_KEYCODE) {
-          event.preventDefault()
-          this.hide()
+          // This will trigger a scale transition if the backdrop is static
+          this._triggerBackdropTransition()
         }
       })
     } else {
@@ -367,11 +369,8 @@ class Modal {
           return
         }
 
-        if (this._config.backdrop === 'static') {
-          this._element.focus()
-        } else {
-          this.hide()
-        }
+        // This will trigger a scale transition if the backdrop is static
+        this._triggerBackdropTransition()
       })
 
       if (animate) {
@@ -409,6 +408,27 @@ class Modal {
     }
   }
 
+  // This function will trigger a HIDE_PREVENTED event and do a scale animation if
+  // the backdrop is static
+  _triggerBackdropTransition() {
+    if (this._config.backdrop === 'static') {
+      const hideEvent = EventHandler.trigger(this._element, Event.HIDE_PREVENTED)
+      if (hideEvent.defaultPrevented) {
+        return
+      }
+
+      this._element.classList.add(ClassName.STATIC)
+      const modalTransitionDuration = getTransitionDurationFromElement(this._element)
+      EventHandler.one(this._element, TRANSITION_END, () => {
+        this._element.classList.remove(ClassName.STATIC)
+      })
+      emulateTransitionEnd(this._element, modalTransitionDuration)
+      this._element.focus()
+    } else {
+      this.hide()
+    }
+  }
+
   // ----------------------------------------------------------------------
   // the following methods are used to handle overflowing modals
   // ----------------------------------------------------------------------

js/tests/unit/modal.spec.js

@@ -540,6 +540,33 @@ describe('Modal', () => {
       modal.show()
     })
 
+    it('should not close modal when clicking outside of modal-content if backdrop = static', done => {
+      fixtureEl.innerHTML = '<div class="modal" data-backdrop="static" ><div class="modal-dialog" /></div>'
+
+      const modalEl = fixtureEl.querySelector('.modal')
+      const modal = new Modal(modalEl, {
+        backdrop: 'static'
+      })
+
+      const shownCallback = () => {
+        setTimeout(() => {
+          expect(modal._isShown).toEqual(true)
+          done()
+        }, 10)
+      }
+
+      modalEl.addEventListener('shown.bs.modal', () => {
+        modalEl.click()
+        shownCallback()
+      })
+
+      modalEl.addEventListener('hidden.bs.modal', () => {
+        throw new Error('Should not hide a modal')
+      })
+
+      modal.show()
+    })
+
     it('should not adjust the inline body padding when it does not overflow', done => {
       fixtureEl.innerHTML = '<div class="modal"><div class="modal-dialog" /></div>'
 

scss/_modal.scss

@@ -48,6 +48,11 @@
   .modal.show & {
     transform: $modal-show-transform;
   }
+
+  // When trying to close, animate focus to scale
+  .modal.modal-static & {
+    transform: scale(1.02);
+  }
 }
 
 .modal-dialog-scrollable {

site/content/docs/4.3/components/modal.md

@@ -140,6 +140,65 @@ Toggle a working modal demo by clicking the button below. It will slide down and
 </div>
 {{< /highlight >}}
 
+### Static backdrop
+
+When backdrop is set to static, the modal will not close when clicking outside it. Click the button below to try it.
+
+<div id="staticBackdropLive" class="modal fade" data-backdrop="static" tabindex="-1" role="dialog" aria-labelledby="staticBackdropLiveLabel" aria-hidden="true">
+  <div class="modal-dialog" role="document">
+    <div class="modal-content">
+      <div class="modal-header">
+        <h5 class="modal-title" id="staticBackdropLiveLabel">Modal title</h5>
+        <button type="button" class="close" data-dismiss="modal" aria-label="Close">
+          <span aria-hidden="true">&times;</span>
+        </button>
+      </div>
+      <div class="modal-body">
+        <p>I'll not close if you click outside me. Don't even try to press escape key.</p>
+      </div>
+      <div class="modal-footer">
+        <button type="button" class="btn btn-secondary" data-dismiss="modal">Close</button>
+        <button type="button" class="btn btn-primary">Understood</button>
+      </div>
+    </div>
+  </div>
+</div>
+
+<div class="bd-example">
+  <button type="button" class="btn btn-primary" data-toggle="modal" data-target="#staticBackdropLive">
+    Launch static backdrop modal
+  </button>
+</div>
+
+{{< highlight html >}}
+<!-- Button trigger modal -->
+<button type="button" class="btn btn-primary" data-toggle="modal" data-target="#staticBackdrop">
+  Launch static backdrop modal
+</button>
+
+<!-- Modal -->
+<div class="modal fade" id="staticBackdrop" data-backdrop="static" tabindex="-1" role="dialog" aria-labelledby="staticBackdropLabel" aria-hidden="true">
+  <div class="modal-dialog" role="document">
+    <div class="modal-content">
+      <div class="modal-header">
+        <h5 class="modal-title" id="staticBackdropLabel">Modal title</h5>
+        <button type="button" class="close" data-dismiss="modal" aria-label="Close">
+          <span aria-hidden="true">&times;</span>
+        </button>
+      </div>
+      <div class="modal-body">
+        ...
+      </div>
+      <div class="modal-footer">
+        <button type="button" class="btn btn-secondary" data-dismiss="modal">Close</button>
+        <button type="button" class="btn btn-primary">Understood</button>
+      </div>
+    </div>
+  </div>
+</div>
+{{< /highlight >}}
+
+
 ### Scrolling long content
 
 When modals become too long for the user's viewport or device, they scroll independent of the page itself. Try the demo below to see what we mean.
@@ -753,7 +812,7 @@ Options can be passed via data attributes or JavaScript. For data attributes, ap
       <td>backdrop</td>
       <td>boolean or the string <code>'static'</code></td>
       <td>true</td>
-      <td>Includes a modal-backdrop element. Alternatively, specify <code>static</code> for a backdrop which doesn't close the modal on click.</td>
+      <td>Includes a modal-backdrop element. Alternatively, specify <code>static</code> for a backdrop which doesn't close the modal on click or on escape key press.</td>
     </tr>
     <tr>
       <td>keyboard</td>
@@ -859,6 +918,10 @@ Bootstrap's modal class exposes a few events for hooking into modal functionalit
       <td>hidden.bs.modal</td>
       <td>This event is fired when the modal has finished being hidden from the user (will wait for CSS transitions to complete).</td>
     </tr>
+    <tr>
+      <td>hidePrevented.bs.modal</td>
+      <td>This event is fired when the modal is shown, its backdrop is <code>static</code> and a click outside the modal or a scape key press is performed.</td>
+    </tr>
   </tbody>
 </table>