break touch interaction into own module

js/controllers/location.js

@@ -1,7 +1,5 @@
-import { enterFullscreen } from '../utils/util.js'
-
 /**
- * Handles all reveal.js keyboard interactions.
+ * Reads and writes the URL based on reveal.js' current state.
  */
 export default class Location {
 

js/controllers/slidenumber.js

@@ -1,7 +1,5 @@
-import { enterFullscreen } from '../utils/util.js'
-
 /**
- * Handles all reveal.js keyboard interactions.
+ * Handles the display of reveal.js' optional slide number.
  */
 export default class SlideNumber {
 

js/controllers/touch.js

@@ -0,0 +1,255 @@
+const SWIPE_THRESHOLD = 40;
+
+/**
+ * Controls all touch interactions and navigations for
+ * a presentation.
+ */
+export default class Touch {
+
+	constructor( Reveal ) {
+
+		this.Reveal = Reveal;
+
+		// Holds information about the currently ongoing touch interaction
+		this.touchStartX = 0;
+		this.touchStartY = 0;
+		this.touchStartCount = 0;
+		this.touchCaptured = false;
+
+		this.onPointerDown = this.onPointerDown.bind( this );
+		this.onPointerMove = this.onPointerMove.bind( this );
+		this.onPointerUp = this.onPointerUp.bind( this );
+		this.onTouchStart = this.onTouchStart.bind( this );
+		this.onTouchMove = this.onTouchMove.bind( this );
+		this.onTouchEnd = this.onTouchEnd.bind( this );
+
+	}
+
+	/**
+	 *
+	 */
+	bind() {
+
+		var revealElement = this.Reveal.getRevealElement();
+
+		if( 'onpointerdown' in window ) {
+			// Use W3C pointer events
+			revealElement.addEventListener( 'pointerdown', this.onPointerDown, false );
+			revealElement.addEventListener( 'pointermove', this.onPointerMove, false );
+			revealElement.addEventListener( 'pointerup', this.onPointerUp, false );
+		}
+		else if( window.navigator.msPointerEnabled ) {
+			// IE 10 uses prefixed version of pointer events
+			revealElement.addEventListener( 'MSPointerDown', this.onPointerDown, false );
+			revealElement.addEventListener( 'MSPointerMove', this.onPointerMove, false );
+			revealElement.addEventListener( 'MSPointerUp', this.onPointerUp, false );
+		}
+		else {
+			// Fall back to touch events
+			revealElement.addEventListener( 'touchstart', this.onTouchStart, false );
+			revealElement.addEventListener( 'touchmove', this.onTouchMove, false );
+			revealElement.addEventListener( 'touchend', this.onTouchEnd, false );
+		}
+
+	}
+
+	/**
+	 *
+	 */
+	unbind() {
+
+		var revealElement = this.Reveal.getRevealElement();
+
+		revealElement.removeEventListener( 'pointerdown', this.onPointerDown, false );
+		revealElement.removeEventListener( 'pointermove', this.onPointerMove, false );
+		revealElement.removeEventListener( 'pointerup', this.onPointerUp, false );
+
+		revealElement.removeEventListener( 'MSPointerDown', this.onPointerDown, false );
+		revealElement.removeEventListener( 'MSPointerMove', this.onPointerMove, false );
+		revealElement.removeEventListener( 'MSPointerUp', this.onPointerUp, false );
+
+		revealElement.removeEventListener( 'touchstart', this.onTouchStart, false );
+		revealElement.removeEventListener( 'touchmove', this.onTouchMove, false );
+		revealElement.removeEventListener( 'touchend', this.onTouchEnd, false );
+
+	}
+
+	/**
+	 * Checks if the target element prevents the triggering of
+	 * swipe navigation.
+	 */
+	isSwipePrevented( target ) {
+
+		while( target && typeof target.hasAttribute === 'function' ) {
+			if( target.hasAttribute( 'data-prevent-swipe' ) ) return true;
+			target = target.parentNode;
+		}
+
+		return false;
+
+	}
+
+	/**
+	 * Handler for the 'touchstart' event, enables support for
+	 * swipe and pinch gestures.
+	 *
+	 * @param {object} event
+	 */
+	onTouchStart( event ) {
+
+		if( this.isSwipePrevented( event.target ) ) return true;
+
+		this.touchStartX = event.touches[0].clientX;
+		this.touchStartY = event.touches[0].clientY;
+		this.touchStartCount = event.touches.length;
+
+	}
+
+	/**
+	 * Handler for the 'touchmove' event.
+	 *
+	 * @param {object} event
+	 */
+	onTouchMove( event ) {
+
+		if( this.isSwipePrevented( event.target ) ) return true;
+
+		let config = this.Reveal.getConfig();
+
+		// Each touch should only trigger one action
+		if( !this.touchCaptured ) {
+			this.Reveal.onUserInput( event );
+
+			let currentX = event.touches[0].clientX;
+			let currentY = event.touches[0].clientY;
+
+			// There was only one touch point, look for a swipe
+			if( event.touches.length === 1 && this.touchStartCount !== 2 ) {
+
+				let deltaX = currentX - this.touchStartX,
+					deltaY = currentY - this.touchStartY;
+
+				if( deltaX > SWIPE_THRESHOLD && Math.abs( deltaX ) > Math.abs( deltaY ) ) {
+					this.touchCaptured = true;
+					if( config.navigationMode === 'linear' ) {
+						if( config.rtl ) {
+							this.Reveal.next();
+						}
+						else {
+							this.Reveal.prev()();
+						}
+					}
+					else {
+						this.Reveal.left();
+					}
+				}
+				else if( deltaX < -SWIPE_THRESHOLD && Math.abs( deltaX ) > Math.abs( deltaY ) ) {
+					this.touchCaptured = true;
+					if( config.navigationMode === 'linear' ) {
+						if( config.rtl ) {
+							this.Reveal.prev()();
+						}
+						else {
+							this.Reveal.next();
+						}
+					}
+					else {
+						this.Reveal.right();
+					}
+				}
+				else if( deltaY > SWIPE_THRESHOLD ) {
+					this.touchCaptured = true;
+					if( config.navigationMode === 'linear' ) {
+						this.Reveal.prev()();
+					}
+					else {
+						this.Reveal.up();
+					}
+				}
+				else if( deltaY < -SWIPE_THRESHOLD ) {
+					this.touchCaptured = true;
+					if( config.navigationMode === 'linear' ) {
+						this.Reveal.next();
+					}
+					else {
+						this.Reveal.down();
+					}
+				}
+
+				// If we're embedded, only block touch events if they have
+				// triggered an action
+				if( config.embedded ) {
+					if( this.touchCaptured || this.Reveal.isVerticalSlide( currentSlide ) ) {
+						event.preventDefault();
+					}
+				}
+				// Not embedded? Block them all to avoid needless tossing
+				// around of the viewport in iOS
+				else {
+					event.preventDefault();
+				}
+
+			}
+		}
+		// There's a bug with swiping on some Android devices unless
+		// the default action is always prevented
+		else if( isAndroid ) {
+			event.preventDefault();
+		}
+
+	}
+
+	/**
+	 * Handler for the 'touchend' event.
+	 *
+	 * @param {object} event
+	 */
+	onTouchEnd( event ) {
+
+		this.touchCaptured = false;
+
+	}
+
+	/**
+	 * Convert pointer down to touch start.
+	 *
+	 * @param {object} event
+	 */
+	onPointerDown( event ) {
+
+		if( event.pointerType === event.MSPOINTER_TYPE_TOUCH || event.pointerType === "touch" ) {
+			event.touches = [{ clientX: event.clientX, clientY: event.clientY }];
+			this.onTouchStart( event );
+		}
+
+	}
+
+	/**
+	 * Convert pointer move to touch move.
+	 *
+	 * @param {object} event
+	 */
+	onPointerMove( event ) {
+
+		if( event.pointerType === event.MSPOINTER_TYPE_TOUCH || event.pointerType === "touch" )  {
+			event.touches = [{ clientX: event.clientX, clientY: event.clientY }];
+			this.onTouchMove( event );
+		}
+
+	}
+
+	/**
+	 * Convert pointer up to touch end.
+	 *
+	 * @param {object} event
+	 */
+	onPointerUp( event ) {
+
+		if( event.pointerType === event.MSPOINTER_TYPE_TOUCH || event.pointerType === "touch" )  {
+			event.touches = [{ clientX: event.clientX, clientY: event.clientY }];
+			this.onTouchEnd( event );
+		}
+
+	}
+
+}