// ========================================================================== // Project: SproutCore - JavaScript Application Framework // Copyright: ©2006-2009 Sprout Systems, Inc. and contributors. // Portions ©2008-2009 Apple Inc. All rights reserved. // License: Licened under MIT license (see license.js) // ========================================================================== sc_require('views/scroll'); /** @class Implements a complete scroller view for menus. This class implements the arrows displayed in a menu to scroll. The main difference with SC.ScrollerView is that there is only vertical scrollers. Value Syncing between SC.MenuScrollView and SC.MenuScrollerView is done using valueBinding. @extends SC.ScrollerView @since SproutCore 1.0 */ SC.MenuScrollerView = SC.ScrollerView.extend({ classNames: ['sc-menu-scroller-view'], // .......................................................... // PROPERTIES // /** Used to set the scrolling direction of the scroller. */ scrollDown: NO, /** The scroller offset value. This value will adjust between the minimum and maximum values that you set. Default is 0. @property */ value: function(key, val) { if (val !== undefined) { // Don't enforce the maximum now, because the scroll view could change // height and we want our content to stay put when it does. this._value = val ; } else { var value = this._value || 0 ; // default value is at top/left return Math.min(value, this.get('maximum')) ; } }.property('maximum').cacheable(), /** The maximum offset value for the scroller. This will be used to calculate the internal height/width of the scroller itself. It is not necessarily the same as the height of a scroll view's content view. When set less than the height of the scroller, the scroller is disabled. @property {Number} */ maximum: 0, /** YES if enable scrollbar, NO to disable it. Scrollbars will automatically disable if the maximum scroll width does not exceed their capacity. @property */ isEnabled: YES, /** Determine the layout direction. Determines whether the scrollbar should appear horizontal or vertical. This must be set when the view is created. Changing this once the view has been created will have no effect. @property */ layoutDirection: SC.LAYOUT_VERTICAL, /** Amount to scroll one vertical line. Defaults to 20px. */ verticalLineScroll: 20, /** This function overrides the default function in SC.Scroller as menus only have vertical scrolling. @property {String} */ ownerScrollValueKey: function() { return 'verticalScrollOffset' ; }.property('layoutDirection').cacheable(), // .......................................................... // INTERNAL SUPPORT // render: function(context, firstTime) { context.addClass('sc-vertical') ; if (firstTime) { if(this.get('scrollDown')){ context.push(' ') ; }else{ context.push(' ') ; } } context.setClass('disabled', !this.get('isEnabled')) ; }, didCreateLayer: function() { var callback, amt, layer; callback = this._sc_scroller_scrollDidChange ; SC.Event.add(this.$(), 'scroll', this, callback) ; // set scrollOffset first time amt = this.get('value') ; layer = this.get('layer') ; layer.scrollTop = amt ; }, willDestroyLayer: function() { var callback = this._sc_scroller_scrollDidChange ; SC.Event.remove(this.$(), 'scroll', this, callback) ; }, mouseEntered: function(evt) { this.set('isMouseOver', YES); this._invokeScrollOnMouseOver(); }, mouseExited: function(evt) { this.set('isMouseOver', NO); }, /** @private */ /** This function overrides the default function in SC.Scroller. SC.MenuScroller and SC.MenuScroll use valueBinding so this function is not neccesary. */ _sc_scroller_valueDidChange: function() { }.observes('value'), // after 50msec, fire event again _sc_scroller_armScrollTimer: function() { if (!this._sc_scrollTimer) { SC.RunLoop.begin() ; var method = this._sc_scroller_scrollDidChange ; this._sc_scrollTimer = this.invokeLater(method, 50) ; SC.RunLoop.end() ; } }, _sc_scroller_scrollDidChange: function() { var now = Date.now(), last = this._sc_lastScroll, layer = this.get('layer'), scroll = 0 ; if (last && (now-last)<50) return this._sc_scroller_armScrollTimer() ; this._sc_scrollTimer = null ; this._sc_lastScroll = now ; SC.RunLoop.begin(); if (!this.get('isEnabled')) return ; // nothing to do. this._sc_scrollValue = scroll = layer.scrollTop ; this.set('value', scroll) ; // will now enforce minimum and maximum SC.RunLoop.end(); }, /** Scroll the menu if it is is an up or down arrow. This is called by the function that simulates mouseOver. */ _scrollMenu: function(){ var val = this.get('value'), newval; if(this.get('scrollDown')) { newval = val+this.verticalLineScroll; if(newval<=this.get('maximum')){ this.set('value', newval); } } else { newval = val-this.verticalLineScroll; if(newval>=0){ this.set('value', newval); }else if(val<=this.verticalLineScroll && val>0){ this.set('value', 0); } } return YES; }, /** We use this function to simulate mouseOver. It checks for the flag isMouseOver which is turned on when mouseEntered is called and turned off when mouseExited is called. */ _invokeScrollOnMouseOver: function(){ this._scrollMenu(); if(this.get('isMouseOver')){ this.invokeLater(this._invokeScrollOnMouseOver, 50); } } }); /** @class Implements a scroll view for menus. This class extends SC.ScrollView for menus. The main difference with SC.ScrollView is that there is only vertical scrolling. Value Syncing between SC.MenuScrollView and SC.MenuScrollerView is done using valueBinding. @extends SC.ScrollView @since SproutCore 1.0 */ SC.MenuScrollView = SC.ScrollView.extend({ classNames: ['sc-menu-scroll-view'], // .......................................................... // PROPERTIES // /** The maximum horizontal scroll offset allowed given the current contentView size and the size of the scroll view. If horizontal scrolling is disabled, this will always return 0. @property {Number} */ maximumHorizontalScrollOffset: function() { }.property(), // .......................................................... // SCROLLERS // /** YES if the view should maintain a horizontal scroller. This property must be set when the view is created. @property {Boolean} */ hasHorizontalScroller: NO, /** The horizontal scroller view class. This will be replaced with a view instance when the ScrollView is created unless hasHorizontalScroller is NO. @property {SC.View} */ horizontalScrollerView: SC.MenuScrollerView, /** YES if the horizontal scroller should be visible. You can change this property value anytime to show or hide the horizontal scroller. If you do not want to use a horizontal scroller at all, you should instead set hasHorizontalScroller to NO to avoid creating a scroller view in the first place. @property {Boolean} */ isHorizontalScrollerVisible: NO, /** Returns YES if the view both has a horizontal scroller, the scroller is visible. @property {Boolean} */ canScrollHorizontal: function() { return false; }.property('isHorizontalScrollerVisible').cacheable(), /** If YES, the horizontal scroller will autohide if the contentView is smaller than the visible area. You must set hasHorizontalScroller to YES for this property to have any effect. */ autohidesHorizontalScroller: NO, /** YES if the view shuld maintain a vertical scroller. This property must be set when the view is created. @property {Boolean} */ hasVerticalScroller: YES, /** The vertical scroller view class. This will be replaced with a view instance when the ScrollView is created unless hasVerticalScroller is NO. @property {SC.View} */ verticalScrollerView: SC.MenuScrollerView, verticalScrollerView2: SC.MenuScrollerView, /** YES if the vertical scroller should be visible. For SC.MenuScroll the vertical scroller is always there we just hide the arrows to scroll. @property {Boolean} */ isVerticalScrollerVisible: YES, canScrollVertical: function() { return YES; }.property('isVerticalScrollerVisible').cacheable(), /** If YES, the vertical scroller will autohide if the contentView is smaller than the visible area. You must set hasVerticalScroller to YES for this property to have any effect. */ autohidesVerticalScroller: YES, /** Use this property to set the 'bottom' offset of your vertical scroller, to make room for a thumb view or other accessory view. Default is 0. @property {Number} */ verticalScrollerBottom: 0, // .......................................................... // CUSTOM VIEWS // /** The container view that will contain your main content view. You can replace this property with your own custom subclass if you prefer. @type {SC.ContainerView} */ containerView: SC.ContainerView, // .......................................................... // METHODS // /** Adjusts the layout for the various internal views. This method is called once when the scroll view is first configured and then anytime a scroller is shown or hidden. You can call this method yourself as well to retile. You may also want to override this method to handle layout for any additional controls you have added to the view. */ tile: function() { // get vertical scroller/determine if we should have a scroller var hasScroller, vscroll, vscroll2, hasVertical, clip, clipLayout, viewportHeight; hasScroller = this.get('hasVerticalScroller'); vscroll = hasScroller ? this.get('verticalScrollerView') : null ; vscroll2 = hasScroller ? this.get('verticalScrollerView2') : null ; hasVertical = vscroll && this.get('isVerticalScrollerVisible') ; // get the containerView clip = this.get('containerView') ; clipLayout = { left: 0, top: 0 } ; if (hasVertical) { viewportHeight =0; var view = this.get('contentView'), view2, f = (view) ? view.get('frame') : null, height = (f) ? f.height : 0, elem = this.containerView.$()[0], verticalOffset = this.get('verticalScrollOffset'), topArrowInvisible = { height: 0, top: 0, right: 0, left: 0 }, topArrowVisible = { height: this.verticalLineScroll, top: 0, right: 0, left: 0 }, bottomArrowVisible = { height: this.verticalLineScroll, bottom: 0, right: 0, left: 0 }, bottomArrowInvisible = { height: 0, bottom: 0, right: 0, left: 0 }; if(elem) viewportHeight = elem.offsetHeight; if(verticalOffset===0){ clipLayout.top = 0 ; clipLayout.bottom = this.verticalLineScroll; vscroll.set('layout', topArrowInvisible) ; vscroll2.set('layout', bottomArrowVisible) ; }else if(verticalOffset>=(height-viewportHeight-this.verticalLineScroll)){ clipLayout.top = this.verticalLineScroll ; clipLayout.bottom = 0 ; vscroll.set('layout', topArrowVisible) ; vscroll2.set('layout', bottomArrowInvisible) ; }else{ clipLayout.top = this.verticalLineScroll ; clipLayout.bottom = this.verticalLineScroll ; vscroll.set('layout', topArrowVisible) ; vscroll2.set('layout', bottomArrowVisible) ; } } if (vscroll){ vscroll.set('isVisible', hasVertical) ; vscroll2.set('isVisible', hasVertical) ; } clip.set('layout', clipLayout) ; }, /** @private Called whenever a scroller visibility changes. Calls the tile() method. */ scrollerVisibilityDidChange: function() { this.tile(); }.observes('isVerticalScrollerVisible', 'isHorizontalScrollerVisible', 'verticalScrollOffset'), // .......................................................... // INTERNAL SUPPORT // /** @private Instantiate scrollers & container views as needed. Replace their classes in the regular properties. */ createChildViews: function() { var childViews = [], view, view2 ; // create the containerView. We must always have a container view. // also, setup the contentView as the child of the containerView... if (SC.none(view = this.containerView)) view = SC.ContainerView; childViews.push(this.containerView = this.createChildView(view, { contentView: this.contentView })); // and replace our own contentView... this.contentView = this.containerView.get('contentView'); // create a vertical scroller if ((view=this.verticalScrollerView) && (view2=this.verticalScrollerView2)) { if (this.get('hasVerticalScroller')) { view = this.verticalScrollerView = this.createChildView(view, { layout: {top: 0, left: 0, right: 0, height: this.verticalLineScroll}, valueBinding: '*owner.verticalScrollOffset' }) ; childViews.push(view); view2 = this.verticalScrollerView2 = this.createChildView(view2, { scrollDown: YES, layout: {bottom: 0, left: 0, right: 0, height: this.verticalLineScroll}, valueBinding: '*owner.verticalScrollOffset' }) ; childViews.push(view2); } else { this.verticalScrollerView = null ; this.verticalScrollerView2 = null ; } } // set childViews array. this.childViews = childViews ; this.contentViewFrameDidChange() ; // setup initial display... this.tile() ; // set up initial tiling }, init: function() { sc_super(); // start observing initial content view. The content view's frame has // already been setup in prepareDisplay so we don't need to call // viewFrameDidChange... this._scroll_contentView = this.get('contentView') ; var contentView = this._scroll_contentView ; if (contentView) { contentView.addObserver('frame', this, this.contentViewFrameDidChange) ; } if (this.get('isVisibleInWindow')) this._scsv_registerAutoscroll() ; }, /** @private Registers/deregisters view with SC.Drag for autoscrolling */ _scsv_registerAutoscroll: function() { if (this.get('isVisibleInWindow')) SC.Drag.addScrollableView(this); else SC.Drag.removeScrollableView(this); }.observes('isVisibleInWindow'), /** @private Whenever the contentView is changed, we need to observe the content view's frame to be notified whenever it's size changes. */ contentViewDidChange: function() { var newView = this.get('contentView'), oldView = this._scroll_contentView, f = this.contentViewFrameDidChange ; if (newView !== oldView) { // stop observing old content view if (oldView) oldView.removeObserver('frame', this, f); // update cache this._scroll_contentView = newView; if (newView) newView.addObserver('frame', this, f); // replace container this.containerView.set('content', newView); this.contentViewFrameDidChange(); } }.observes('contentView'), /** @private Invoked whenever the contentView's frame changes. This will update the scroller maxmimum and optionally update the scroller visibility if the size of the contentView changes. We don't care about the origin since that is tracked separately from the offset values. */ contentViewFrameDidChange: function() { var view = this.get('contentView'), view2, f = (view) ? view.get('frame') : null, width = (f) ? f.width : 0, height = (f) ? f.height : 0, dim = this.get('frame'), viewportHeight, elem ; // cache out scroll settings... //if ((width === this._scroll_contentWidth) && (height === this._scroll_contentHeight)) return ; this._scroll_contentWidth = width; this._scroll_contentHeight = height ; if (this.get('hasVerticalScroller') && (view = this.get('verticalScrollerView')) && (view2 = this.get('verticalScrollerView2'))) { height -= 1 ; // accurately account for our layout // decide if it should be visible or not if (this.get('autohidesVerticalScroller')) { this.set('isVerticalScrollerVisible', height > dim.height); } height -= this.get('verticalScrollerBottom') ; viewportHeight = 0; elem = this.containerView.$()[0]; if(elem) viewportHeight = elem.offsetHeight; height = height - viewportHeight; view.setIfChanged('maximum', height) ; view2.setIfChanged('maximum', height) ; } }, /** @private Whenever the horizontal scroll offset changes, update the scrollers and edit the location of the contentView. */ _scroll_horizontalScrollOffsetDidChange: function() { }.observes('horizontalScrollOffset'), /** @private Whenever the vertical scroll offset changes, update the scrollers and edit the location of the contentView. */ _scroll_verticalScrollOffsetDidChange: function() { var offset = this.get('verticalScrollOffset') ; // update the offset for the contentView... var contentView = this.get('contentView'); if (contentView) contentView.adjust('top', 0-offset) ; }.observes('verticalScrollOffset') });