dispatch events when visible fragment changes ('fragmentshown', 'fragmenthidden') closes #44

README.md

@@ -88,6 +88,19 @@ Reveal.addEventListener( 'slidechanged', function( event ) {
 } );
 ```
 
+### Fragment events
+
+When a slide fragment is either shown or hidden reveal.js will dispatch an event.
+
+```
+Reveal.addEventListener( 'fragmentshown', function( event ) {
+	// event.fragment = the fragment DOM element
+} );
+Reveal.addEventListener( 'fragmenthidden', function( event ) {
+	// event.fragment = the fragment DOM element
+} );
+```
+
 
 ## Examples
 
@@ -126,6 +139,7 @@ Reveal.addEventListener( 'slidechanged', function( event ) {
 - Added print styles. Thanks [skypanther](https://github.com/skypanther)
 - The address bar now hides automatically on mobile browsers
 - Space and return keys can be used to exit the overview mode
+- Events for fragment states ('fragmentshown'/'fragmenthidden')
 
 #### 1.2
 

js/reveal.js

@@ -654,6 +654,9 @@ var Reveal = (function(){
 			var verticalFragments = document.querySelectorAll( VERTICAL_SLIDES_SELECTOR + '.present .fragment:not(.visible)' );
 			if( verticalFragments.length ) {
 				verticalFragments[0].classList.add( 'visible' );
+
+				// Notify subscribers of the change
+				dispatchEvent( 'fragmentshown', { fragment: verticalFragments[0] } );
 				return true;
 			}
 		}
@@ -662,6 +665,9 @@ var Reveal = (function(){
 			var horizontalFragments = document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR + '.present .fragment:not(.visible)' );
 			if( horizontalFragments.length ) {
 				horizontalFragments[0].classList.add( 'visible' );
+
+				// Notify subscribers of the change
+				dispatchEvent( 'fragmentshown', { fragment: horizontalFragments[0] } );
 				return true;
 			}
 		}
@@ -681,6 +687,9 @@ var Reveal = (function(){
 			var verticalFragments = document.querySelectorAll( VERTICAL_SLIDES_SELECTOR + '.present .fragment.visible' );
 			if( verticalFragments.length ) {
 				verticalFragments[ verticalFragments.length - 1 ].classList.remove( 'visible' );
+
+				// Notify subscribers of the change
+				dispatchEvent( 'fragmenthidden', { fragment: verticalFragments[0] } );
 				return true;
 			}
 		}
@@ -689,6 +698,9 @@ var Reveal = (function(){
 			var horizontalFragments = document.querySelectorAll( HORIZONTAL_SLIDES_SELECTOR + '.present .fragment.visible' );
 			if( horizontalFragments.length ) {
 				horizontalFragments[ horizontalFragments.length - 1 ].classList.remove( 'visible' );
+
+				// Notify subscribers of the change
+				dispatchEvent( 'fragmenthidden', { fragment: horizontalFragments[0] } );
 				return true;
 			}
 		}

js/reveal.min.js

@@ -42,10 +42,11 @@ continue stateLoop;}}document.documentElement.classList.add(N[R]);o(N[R]);}while
 }function C(){var P=window.location.hash.slice(2).split("/");k=parseInt(P[0])||0;c=parseInt(P[1])||0;E(k,c);}function g(){if(G.history){var P="/";if(k>0||c>0){P+=k;
 }if(c>0){P+="/"+c;}window.location.hash=P;}}function o(Q,P){var R=document.createEvent("HTMLEvents",1,2);R.initEvent(Q,true,true);q(R,P);d.wrapper.dispatchEvent(R);
 }function s(){if(document.querySelector(a+".present")){var Q=document.querySelectorAll(a+".present .fragment:not(.visible)");if(Q.length){Q[0].classList.add("visible");
-return true;}}else{var P=document.querySelectorAll(j+".present .fragment:not(.visible)");if(P.length){P[0].classList.add("visible");return true;}}return false;
+o("fragmentshown",{fragment:Q[0]});return true;}}else{var P=document.querySelectorAll(j+".present .fragment:not(.visible)");if(P.length){P[0].classList.add("visible");
-}function F(){if(document.querySelector(a+".present")){var Q=document.querySelectorAll(a+".present .fragment.visible");if(Q.length){Q[Q.length-1].classList.remove("visible");
+o("fragmentshown",{fragment:P[0]});return true;}}return false;}function F(){if(document.querySelector(a+".present")){var Q=document.querySelectorAll(a+".present .fragment.visible");
-return true;}}else{var P=document.querySelectorAll(j+".present .fragment.visible");if(P.length){P[P.length-1].classList.remove("visible");return true;}}return false;
+if(Q.length){Q[Q.length-1].classList.remove("visible");o("fragmenthidden",{fragment:Q[0]});return true;}}else{var P=document.querySelectorAll(j+".present .fragment.visible");
-}function E(Q,P){k=Q===undefined?k:Q;c=P===undefined?c:P;b();}function x(){if(J()||F()===false){k--;c=0;b();}}function i(){if(J()||s()===false){k++;c=0;
+if(P.length){P[P.length-1].classList.remove("visible");o("fragmenthidden",{fragment:P[0]});return true;}}return false;}function E(Q,P){k=Q===undefined?k:Q;
-b();}}function r(){if(J()||F()===false){c--;b();}}function A(){if(J()||s()===false){c++;b();}}function I(){if(F()===false){if(f().up){r();}else{var P=document.querySelector("#reveal .slides>section.past:nth-child("+k+")");
+c=P===undefined?c:P;b();}function x(){if(J()||F()===false){k--;c=0;b();}}function i(){if(J()||s()===false){k++;c=0;b();}}function r(){if(J()||F()===false){c--;
+b();}}function A(){if(J()||s()===false){c++;b();}}function I(){if(F()===false){if(f().up){r();}else{var P=document.querySelector("#reveal .slides>section.past:nth-child("+k+")");
 if(P){c=(P.querySelectorAll("section").length+1)||0;k--;b();}}}}function u(){if(s()===false){f().down?A():i();}}return{initialize:h,navigateTo:E,navigateLeft:x,navigateRight:i,navigateUp:r,navigateDown:A,addEventListener:function(Q,R,P){(d.wrapper||document.querySelector("#reveal")).addEventListener(Q,R,P);
 },removeEventListener:function(Q,R,P){(d.wrapper||document.querySelector("#reveal")).removeEventListener(Q,R,P);}};})();