atlasuidragdrop.js

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    this.get_data = function() {
        return _data;
    }
    
    this.set_data = function(value) {
        _data = value;
    }
    
    this.initialize = function() {
        Web.UI.DragDropList.callBaseMethod(this, 'initialize');
        this.control.element.__dragDropList = this;
        Web.UI.DragDropManager.registerDropTarget(this);
    }
    
    this.getDescriptor = function() {
        var td = Web.UI.DragDropList.callBaseMethod(this, 'getDescriptor');
        td.addProperty("acceptedDataTypes", Array);
        td.addProperty("data", Object);
        td.addProperty("dataType", String);
        td.addProperty("emptyTemplate", Web.UI.ITemplate);
        td.addProperty("dropCueTemplate", Web.UI.ITemplate);
        td.addProperty("direction", Web.UI.RepeatDirection);
        td.addProperty("dragMode", Web.UI.DragMode);
        return td;
    }
    Web.UI.DragDropList.registerBaseMethod(this, 'getDescriptor');
    
        
    this.startDragDrop = function(dragObject, context, dragVisual) {
        if (!_isDragging) {
            _isDragging = true;
            _currentContext = context;
            if (dragVisual == null) {
                dragVisual = this.createDragVisual(dragObject);
debug.trace("Using default drag visual.");
            }
            else {
                _dragVisual = dragVisual;
debug.trace("Using user-specified drag visual.");
            }
            Web.UI.DragDropManager.startDragDrop(this, dragVisual, context);
        }
        else {
            debug.trace("Drag drop rejected by DragDropList: already dragging.");
        }
    }
    
    this.createDragVisual = function(dragObject) {
        if (_dragMode == Web.UI.DragMode.Copy) {
            _dragVisual = dragObject.cloneNode(true);
        }
        else {
            _dragVisual = dragObject;
        }
        
        var oldOffset = Web.UI.DragDropManager._getInstance().getScrollOffset(dragObject, true);
        
        _dragVisual.style.width = dragObject.offsetWidth + "px";
        _dragVisual.style.height = dragObject.offsetHeight + "px";
        
        _dragVisual.style.opacity = "0.4";
        _dragVisual.style.filter = "progid:DXImageTransform.Microsoft.BasicImage(opacity=0.4);";
        _originalZIndex = _dragVisual.style.zIndex;
        _dragVisual.style.zIndex = 99999;
        
        _originalParent = _dragVisual.parentNode;
        _originalNextSibling = Web.UI.DragDropManager._getInstance().getNextSibling(_dragVisual);
        
        var currentLocation = Web.UI.Control.getLocation(dragObject, true);
        
                var dragVisualContainer = this._getFloatContainer();
        Web.UI.Control.setLocation(dragVisualContainer, currentLocation);
        
        if (Web.UI.DragDropManager._getInstance().hasParent(_dragVisual)) {
            _dragVisual.parentNode.removeChild(_dragVisual);
        }
        dragVisualContainer.appendChild(_dragVisual);
        
        var newOffset = Web.UI.DragDropManager._getInstance().getScrollOffset(dragObject, true);
        if (oldOffset.x != newOffset.x || oldOffset.y != newOffset.y) {
            var diff = Web.UI.DragDropManager._getInstance().subtractPoints(oldOffset, newOffset);
            Web.UI.Control.setLocation(dragVisualContainer, Web.UI.DragDropManager._getInstance().subtractPoints(currentLocation, diff));
        }
        
        return dragVisualContainer;
    }
    
    this.get_emptyTemplate = function() {
        return _emptyTemplate;
    }
    
    this.set_emptyTemplate = function(value) {
        _emptyTemplate = value;
    }
    
        this.get_dataType = function() {
        return _dataType;
    }
    
    this.set_dataType = function(value) {
        _dataType = value;
    }
    
        this.get_data = function(context) {
        return context;
    }
    
        this.get_dragMode = function() {
        return _dragMode;
    }
    
    this.set_dragMode = function(value) {
        _dragMode = value;
    }
    
    this.dispose = function() {
        this.control.element.__dragDropList = null;
        Web.UI.DragDropList.callBaseMethod(this, 'dispose');
    }
    
        this.onDragStart = function() {
        this._validate();
    }
    
        this.onDrag = function() {
            }
    
        this.onDragEnd = function(cancelled) {
        if (_floatContainerInstance != null) {
            if (_dragMode == Web.UI.DragMode.Copy) {
                _floatContainerInstance.removeChild(_dragVisual);
            }
            else {
                                                _dragVisual.style.opacity = "0.999";
                                _dragVisual.style.filter = "";
                
                _dragVisual.style.zIndex = _originalZIndex ? _originalZIndex : 0;
            
                if (cancelled) {
                                        _dragVisual.parentNode.removeChild(_dragVisual);
                    if (_originalNextSibling != null) {
                        _originalParent.insertBefore(_dragVisual, _originalNextSibling);
                    }
                    else {
                        _originalParent.appendChild(_dragVisual);
                    }
                }
                else {
                    if (_dragVisual.parentNode == _floatContainerInstance) {
                        _dragVisual.parentNode.removeChild(_dragVisual);
                    }
                }
            }
            
                        document.body.removeChild(_floatContainerInstance);
        }
        else {
            _dragVisual.parentNode.removeChild(_dragVisual);
        }
        
        if (!cancelled && _data != null && _dragMode == Web.UI.DragMode.Move) {
            var data = this.get_data(_currentContext);
            if (_data != null && data != null) {
                _data.remove(data);
            }
        }
        
        _isDragging = false;
        this._validate();
    }
    
        
    this.get_direction = function() {
        return _direction;
    }
    
    this.set_direction = function(value) {
        _direction = value;
    }
    
    this.get_acceptedDataTypes = function() {
        return _acceptedDataTypes;
    }
    
    this.set_acceptedDataTypes = function(value) {
        _acceptedDataTypes = value;
    }
    
    this.get_dropCueTemplate = function() {
        return _dropCueTemplate;
    }
    
    this.set_dropCueTemplate = function(value) {
        _dropCueTemplate = value;
    }

    this.get_dropTargetElement = function() {
        return this.control.element;
    }
    
        this.canDrop = function(dragMode, dataType) {
        for (var i = 0; i < _acceptedDataTypes.length; i++) {
            if (_acceptedDataTypes[i] == dataType) {
                return true;
            }
        }
        
        return false;
    }
    
        this.drop = function(dragMode, dataType, data) {
        if (dataType == "HTML" && dragMode == Web.UI.DragMode.Move) {
                        dragVisual = data;
            
            var potentialNextSibling = this._findPotentialNextSibling(dragVisual);
            this._setDropCueVisible(false, dragVisual);
            dragVisual.parentNode.removeChild(dragVisual);
            if (potentialNextSibling != null) {
                this.control.element.insertBefore(dragVisual, potentialNextSibling);
            }
            else {
                this.control.element.appendChild(dragVisual);
            }
        }
        else {
            this._setDropCueVisible(false);
        }
        
        if (_data != null && data != null) {
            _data.add(data);
        }
    }
    
        this.onDragEnterTarget = function(dragMode, dataType, data) {
        if (dataType == "HTML") {
            this._setDropCueVisible(true, data);
            this._validate();
        }
    }
    
        this.onDragLeaveTarget = function(dragMode, dataType, data) {
        if (dataType == "HTML") {
            this._setDropCueVisible(false);
            this._validate();
        }
    }
    
        this.onDragInTarget = function(dragMode, dataType, data) {
        if (dataType == "HTML") {
            this._setDropCueVisible(true, data);
        }
    }
    
    this._setDropCueVisible = function(visible, dragVisual) {
        if (_dropCueTemplate != null) {
            if (visible) {
                if (_dropCueTemplateInstance == null) {
                    var documentContext = document.createDocumentFragment();
                    _dropCueTemplateInstance = _dropCueTemplate.createInstance(documentContext).instanceElement;
                }
                
                var potentialNextSibling = this._findPotentialNextSibling(dragVisual);
                
                if (!Web.UI.DragDropManager._getInstance().hasParent(_dropCueTemplateInstance)) {
                                        if (potentialNextSibling != null) {
                        this.control.element.insertBefore(_dropCueTemplateInstance, potentialNextSibling);
                    }
                    else {
                        this.control.element.appendChild(_dropCueTemplateInstance);
                    }
                        
                    _dropCueTemplateInstance.style.width = dragVisual.offsetWidth + "px";
                    _dropCueTemplateInstance.style.height = dragVisual.offsetHeight + "px";
                }
                else {
                                        if (Web.UI.DragDropManager._getInstance().getNextSibling(_dropCueTemplateInstance) != potentialNextSibling) {
                        this.control.element.removeChild(_dropCueTemplateInstance);
                        if (potentialNextSibling != null) {
                            this.control.element.insertBefore(_dropCueTemplateInstance, potentialNextSibling);
                        }
                        else {
                            this.control.element.appendChild(_dropCueTemplateInstance);
                        }
                    }
                }
            }
            else {
                if (_dropCueTemplateInstance != null && Web.UI.DragDropManager._getInstance().hasParent(_dropCueTemplateInstance)) {
                    this.control.element.removeChild(_dropCueTemplateInstance);
                }
            }
        }
    }
    
    this._findPotentialNextSibling = function(dragVisual) {
        var dragVisualRect = Web.UI.Control.getBounds(dragVisual);
        var isVertical = (_direction == Web.UI.RepeatDirection.Vertical);
        var nodeRect;
        for (var node = this.control.element.firstChild; node != null; node = node.nextSibling) {
            if (node.innerHTML != null && node != _dropCueTemplateInstance && node != _emptyTemplateInstance) {
                nodeRect = Web.UI.Control.getBounds(node);
                if ((!isVertical && dragVisualRect.x <= nodeRect.x) || (isVertical && dragVisualRect.y <= nodeRect.y)) {
                    return node;
                }
            }
        }
        
        return null;
    }
    
    this._validate = function() {
        var visible = (_dropCueTemplateInstance == null || !Web.UI.DragDropManager._getInstance().hasParent(_dropCueTemplateInstance));

                var count = 0;
        for (var node = this.control.element.firstChild; node != null; node = node.nextSibling) {
            if (node.innerHTML != null && node != _emptyTemplateInstance && node != _dropCueTemplateInstance) {
                count++;
            }
        }
        
        if (count > 0) {
            visible = false;
        }
        this._setEmptyTemplateVisible(visible);
    }
    
    this._setEmptyTemplateVisible = function(visible) {
        if (_emptyTemplate != null) {
            if (visible) {
                if (_emptyTemplateInstance == null) {
                    _emptyTemplateInstance = _emptyTemplate.createInstance(this.control.element).instanceElement;
                }
                else if (!Web.UI.DragDropManager._getInstance().hasParent(_emptyTemplateInstance)) {
                    this.control.element.appendChild(_emptyTemplateInstance);
                }
            }
            else {
                if (_emptyTemplateInstance != null && Web.UI.DragDropManager._getInstance().hasParent(_emptyTemplateInstance)) {
                    this.control.element.removeChild(_emptyTemplateInstance);
                }
            }
        }
    }
    
    this._getFloatContainer = function() {
        if (_floatContainerInstance == null) {
            _floatContainerInstance = document.createElement(this.control.element.tagName);
            var none = "0px 0px 0px 0px";
            _floatContainerInstance.style.position = "absolute";
            _floatContainerInstance.style.padding = none;
            _floatContainerInstance.style.margin = none;
            document.body.appendChild(_floatContainerInstance);
        }
        else if (!Web.UI.DragDropManager._getInstance().hasParent(_floatContainerInstance)) {
            document.body.appendChild(_floatContainerInstance);
        }
        
        return _floatContainerInstance;
    }
}
Type.registerSealedClass('Web.UI.DragDropList', Web.UI.Behavior, Web.UI.IDragSource, Web.UI.IDropTarget, Web.IDisposable);