/**
* angular-drag-and-drop-lists v1.2.0
*
* Copyright (c) 2014 Marcel Juenemann mail@marcel-junemann.de
* https://github.com/marceljuenemann/angular-drag-and-drop-lists
*
* License: MIT
*/
angular.module('dndLists', [])
/**
* Use the dnd-draggable attribute to make your element draggable
*
* Attributes:
* - dnd-draggable Required attribute. The value has to be an object that represents the data
* of the element. In case of a drag and drop operation the object will be
* serialized and unserialized on the receiving end.
* - dnd-selected Callback that is invoked when the element was clicked but not dragged.
* The original click event will be provided in the local event variable.
* - dnd-effect-allowed Use this attribute to limit the operations that can be performed. Options:
* - "move": The drag operation will move the element. This is the default.
* - "copy": The drag operation will copy the element. Shows a copy cursor.
* - "copyMove": The user can choose between copy and move by pressing the
* ctrl or shift key. *Not supported in IE:* In Internet Explorer this
* option will be the same as "copy". *Not fully supported in Chrome on
* Windows:* In the Windows version of Chrome the cursor will always be the
* move cursor. However, when the user drops an element and has the ctrl
* key pressed, we will perform a copy anyways.
* - HTML5 also specifies the "link" option, but this library does not
* actively support it yet, so use it at your own risk.
* - dnd-moved Callback that is invoked when the element was moved. Usually you will
* remove your element from the original list in this callback, since the
* directive is not doing that for you automatically. The original dragend
* event will be provided in the local event variable.
* - dnd-copied Same as dnd-moved, just that it is called when the element was copied
* instead of moved. The original dragend event will be provided in the local
* event variable.
* - dnd-dragstart Callback that is invoked when the element was dragged. The original
* dragstart event will be provided in the local event variable.
* - dnd-type Use this attribute if you have different kinds of items in your
* application and you want to limit which items can be dropped into which
* lists. Combine with dnd-allowed-types on the dnd-list(s). This attribute
* should evaluate to a string, although this restriction is not enforced.
* - dnd-disable-if You can use this attribute to dynamically disable the draggability of the
* element. This is useful if you have certain list items that you don't want
* to be draggable, or if you want to disable drag & drop completely without
* having two different code branches (e.g. only allow for admins).
* **Note**: If your element is not draggable, the user is probably able to
* select text or images inside of it. Since a selection is always draggable,
* this breaks your UI. You most likely want to disable user selection via
* CSS (see user-select).
*
* CSS classes:
* - dndDragging This class will be added to the element while the element is being
* dragged. It will affect both the element you see while dragging and the
* source element that stays at it's position. Do not try to hide the source
* element with this class, because that will abort the drag operation.
* - dndDraggingSource This class will be added to the element after the drag operation was
* started, meaning it only affects the original element that is still at
* it's source position, and not the "element" that the user is dragging with
* his mouse pointer.
*/
.directive('dndDraggable', ['$parse', '$timeout', 'dndDropEffectWorkaround', 'dndDragTypeWorkaround',
function($parse, $timeout, dndDropEffectWorkaround, dndDragTypeWorkaround) {
return function(scope, element, attr) {
// Set the HTML5 draggable attribute on the element
element.attr("draggable", "true");
// If the dnd-disable-if attribute is set, we have to watch that
if (attr.dndDisableIf) {
scope.$watch(attr.dndDisableIf, function(disabled) {
element.attr("draggable", !disabled);
});
}
/**
* When the drag operation is started we have to prepare the dataTransfer object,
* which is the primary way we communicate with the target element
*/
element.on('dragstart', function(event) {
event = event.originalEvent || event;
// Serialize the data associated with this element. IE only supports the Text drag type
event.dataTransfer.setData("Text", angular.toJson(scope.$eval(attr.dndDraggable)));
// Only allow actions specified in dnd-effect-allowed attribute
event.dataTransfer.effectAllowed = attr.dndEffectAllowed || "move";
// Add CSS classes. See documentation above
element.addClass("dndDragging");
// Workarounds for stupid browsers, see description below
dndDropEffectWorkaround.dropEffect = "none";
dndDragTypeWorkaround.isDragging = true;
// <FLOWABLE>
// This code was originally placed after element.addClass.
// This timeout is invoked after the 'dragend' event in IE9 (at leats on slooow virtual box)
// and since this class is used to hide elements it seems like the element is gone,
// therefor make sure the dragging still is happening when adding this class
$timeout(function() {
// Flowable This code
if (dndDragTypeWorkaround.isDragging) {
element.addClass("dndDraggingSource");
}
}, 0);
// </FLOWABLE>
// Save type of item in global state. Usually, this would go into the dataTransfer
// typename, but we have to use "Text" there to support IE
dndDragTypeWorkaround.dragType = attr.dndType ? scope.$eval(attr.dndType) : undefined;
// Invoke callback
$parse(attr.dndDragstart)(scope, {event: event});
event.stopPropagation();
});
/**
* The dragend event is triggered when the element was dropped or when the drag
* operation was aborted (e.g. hit escape button). Depending on the executed action
* we will invoke the callbacks specified with the dnd-moved or dnd-copied attribute.
*/
element.on('dragend', function(event) {
event = event.originalEvent || event;
// Invoke callbacks. Usually we would use event.dataTransfer.dropEffect to determine
// the used effect, but Chrome has not implemented that field correctly. On Windows
// it always sets it to 'none', while Chrome on Linux sometimes sets it to something
// else when it's supposed to send 'none' (drag operation aborted).
var dropEffect = dndDropEffectWorkaround.dropEffect;
scope.$apply(function() {
switch (dropEffect) {
case "move":
$parse(attr.dndMoved)(scope, {event: event});
break;
case "copy":
$parse(attr.dndCopied)(scope, {event: event});
break;
}
});
// Clean up
element.removeClass("dndDragging");
element.removeClass("dndDraggingSource");
dndDragTypeWorkaround.isDragging = false;
event.stopPropagation();
});
/**
* When the element is clicked we invoke the callback function
* specified with the dnd-selected attribute.
*/
element.on('click', function(event) {
event = event.originalEvent || event;
scope.$apply(function() {
$parse(attr.dndSelected)(scope, {event: event});
});
event.stopPropagation();
});
/**
* Workaround to make element draggable in IE9
*/
element.on('selectstart', function() {
if (this.dragDrop) this.dragDrop();
return false;
});
};
}])
/**
* Use the dnd-list attribute to make your list element a dropzone. Usually you will add a single
* li element as child with the ng-repeat directive. If you don't do that, we will not be able to
* position the dropped element correctly. If you want your list to be sortable, also add the
* dnd-draggable directive to your li element(s). Both the dnd-list and it's direct children must
* have position: relative CSS style, otherwise the positioning algorithm will not be able to
* determine the correct placeholder position in all browsers.
*
* Attributes:
* - dnd-list Required attribute. The value has to be the array in which the data of
* the dropped element should be inserted.
* - dnd-allowed-types Optional array of allowed item types. When used, only items that had a
* matching dnd-type attribute will be dropable.
* - dnd-disable-if Optional boolean expresssion. When it evaluates to true, no dropping
* into the list is possible. Note that this also disables rearranging
* items inside the list.
* - dnd-horizontal-list Optional boolean expresssion. When it evaluates to true, the positioning
* algorithm will use the left and right halfs of the list items instead of
* the upper and lower halfs.
* - dnd-dragover Optional expression that is invoked when an element is dragged over the
* list. If the expression is set, but does not return true, the element is
* not allowed to be dropped. The following variables will be available:
* - event: The original dragover event sent by the browser.
* - index: The position in the list at which the element would be dropped.
* - type: The dnd-type set on the dnd-draggable, or undefined if unset.
* - dnd-drop Optional expression that is invoked when an element is dropped over the
* list. If the expression is set, it must return the object that will be
* inserted into the list. If it returns false, the drop will be aborted
* and the event is propagated. The following variables will be available:
* - event: The original drop event sent by the browser.
* - index: The position in the list at which the element would be dropped.
* - item: The transferred object.
* - type: The dnd-type set on the dnd-draggable, or undefined if unset.
* - dnd-external-sources Optional boolean expression. When it evaluates to true, the list accepts
* drops from sources outside of the current browser tab. This allows to
* drag and drop accross different browser tabs. Note that this will allow
* to drop arbitrary text into the list, thus it is highly recommended to
* implement the dnd-drop callback to check the incoming element for
* sanity. Furthermore, the dnd-type of external sources can not be
* determined, therefore do not rely on restrictions of dnd-allowed-type.
*
* CSS classes:
* - dndPlaceholder When an element is dragged over the list, a new placeholder child
* element will be added. This element is of type li and has the class
* dndPlaceholder set.
* - dndDragover Will be added to the list while an element is dragged over the list.
*/
.directive('dndList', ['$parse', '$timeout', 'dndDropEffectWorkaround', 'dndDragTypeWorkaround',
function($parse, $timeout, dndDropEffectWorkaround, dndDragTypeWorkaround) {
return function(scope, element, attr) {
// While an element is dragged over the list, this placeholder element is inserted
// at the location where the element would be inserted after dropping
var placeholder = angular.element("<li class='dndPlaceholder'></li>");
var placeholderNode = placeholder[0];
var listNode = element[0];
var horizontal = attr.dndHorizontalList && scope.$eval(attr.dndHorizontalList);
var externalSources = attr.dndExternalSources && scope.$eval(attr.dndExternalSources);
/**
* The dragover event is triggered "every few hundred milliseconds" while an element
* is being dragged over our list, or over an child element.
*/
element.on('dragover', function(event) {
event = event.originalEvent || event;
if (!isDropAllowed(event)) {
return true;
}
// First of all, make sure that the placeholder is shown
// This is especially important if the list is empty
if (placeholderNode.parentNode != listNode) {
element.append(placeholder);
}
if (event.target !== listNode) {
// Try to find the node direct directly below the list node.
var listItemNode = event.target;
while (listItemNode.parentNode !== listNode && listItemNode.parentNode) {
listItemNode = listItemNode.parentNode;
}
if (listItemNode.parentNode === listNode && listItemNode !== placeholderNode) {
// If the mouse pointer is in the upper half of the child element,
// we place it before the child element, otherwise below it.
if (isMouseInFirstHalf(event, listItemNode)) {
listNode.insertBefore(placeholderNode, listItemNode);
} else {
listNode.insertBefore(placeholderNode, listItemNode.nextSibling);
}
}
} else {
// This branch is reached when we are dragging directly over the list element.
// Usually we wouldn't need to do anything here, but the IE does not fire it's
// events for the child element, only for the list directly. Therefore we repeat
// the positioning algorithm for IE here.
if (isMouseInFirstHalf(event, placeholderNode, true)) {
// Check if we should move the placeholder element one spot towards the top.
// Note that display none elements will have offsetTop and offsetHeight set to
// zero, therefore we need a special check for them.
while (placeholderNode.previousElementSibling
&& (isMouseInFirstHalf(event, placeholderNode.previousElementSibling, true)
|| placeholderNode.previousElementSibling.offsetHeight === 0)) {
listNode.insertBefore(placeholderNode, placeholderNode.previousElementSibling);
}
} else {
// Check if we should move the placeholder element one spot towards the bottom
while (placeholderNode.nextElementSibling &&
!isMouseInFirstHalf(event, placeholderNode.nextElementSibling, true)) {
listNode.insertBefore(placeholderNode,
placeholderNode.nextElementSibling.nextElementSibling);
}
}
}
// At this point we invoke the callback, which still can disallow the drop.
// We can't do this earlier because we want to pass the index of the placeholder.
if (attr.dndDragover && !invokeCallback(attr.dndDragover, event)) {
return stopDragover();
}
element.addClass("dndDragover");
event.preventDefault();
event.stopPropagation();
return false;
});
/**
* When the element is dropped, we use the position of the placeholder element as the
* position where we insert the transferred data. This assumes that the list has exactly
* one child element per array element.
*/
element.on('drop', function(event) {
event = event.originalEvent || event;
if (!isDropAllowed(event)) return true;
// The default behavior in Firefox is to interpret the dropped element as URL and
// forward to it. We want to prevent that even if our drop is aborted.
event.preventDefault();
// Unserialize the data that was serialized in dragstart. According to the HTML5 specs,
// the "Text" drag type will be converted to text/plain, but IE does not do that.
var data = event.dataTransfer.getData("Text") || event.dataTransfer.getData("text/plain");
var transferredObject;
try {
transferredObject = JSON.parse(data);
} catch(e) {
return stopDragover();
}
// Invoke the callback, which can transform the transferredObject and even abort the drop.
if (attr.dndDrop) {
transferredObject = invokeCallback(attr.dndDrop, event, transferredObject);
if (!transferredObject) {
return stopDragover();
}
}
// Retrieve the JSON array and insert the transferred object into it.
var targetArray = scope.$eval(attr.dndList);
scope.$apply(function() {
targetArray.splice(getPlaceholderIndex(), 0, transferredObject);
});
// Invoke the callback, after the transfered objrct is added to the new container.
if (attr.dndAfterDrop) {
invokeCallback(attr.dndAfterDrop, event, transferredObject);
}
// In Chrome on Windows the dropEffect will always be none...
// We have to determine the actual effect manually from the allowed effects
if (event.dataTransfer.dropEffect === "none") {
if (event.dataTransfer.effectAllowed === "copy" ||
event.dataTransfer.effectAllowed === "move") {
dndDropEffectWorkaround.dropEffect = event.dataTransfer.effectAllowed;
} else {
dndDropEffectWorkaround.dropEffect = event.ctrlKey ? "copy" : "move";
}
} else {
dndDropEffectWorkaround.dropEffect = event.dataTransfer.dropEffect;
}
// Clean up
stopDragover();
event.stopPropagation();
return false;
});
/**
* We have to remove the placeholder when the element is no longer dragged over our list. The
* problem is that the dragleave event is not only fired when the element leaves our list,
* but also when it leaves a child element -- so practically it's fired all the time. As a
* workaround we wait a few milliseconds and then check if the dndDragover class was added
* again. If it is there, dragover must have been called in the meantime, i.e. the element
* is still dragging over the list. If you know a better way of doing this, please tell me!
*/
element.on('dragleave', function(event) {
event = event.originalEvent || event;
element.removeClass("dndDragover");
$timeout(function() {
if (!element.hasClass("dndDragover")) {
placeholder.remove();
}
}, 100);
});
/**
* Checks whether the mouse pointer is in the first half of the given target element.
*
* In Chrome we can just use offsetY, but in Firefox we have to use layerY, which only
* works if the child element has position relative. In IE the events are only triggered
* on the listNode instead of the listNodeItem, therefore the mouse positions are
* relative to the parent element of targetNode.
*/
function isMouseInFirstHalf(event, targetNode, relativeToParent) {
var mousePointer = horizontal ? (event.offsetX || event.layerX)
: (event.offsetY || event.layerY);
var targetSize = horizontal ? targetNode.offsetWidth : targetNode.offsetHeight;
var targetPosition = horizontal ? targetNode.offsetLeft : targetNode.offsetTop;
targetPosition = relativeToParent ? targetPosition : 0;
return mousePointer < targetPosition + targetSize / 2;
}
/**
* Flowable-patched version of isMouseInFirstHalf that uses page and bounding client rect
* instead of the offsetX and layerX properties to determine which half of target the mouse pointer is hovering
* this is more natural since th method now actually works like above, but it also adds some mild
* flickering when sorting inside the list, why its still not in use.
*/
function isMouseInFirstHalf_new(event, targetNode, relativeToParent) {
var targetNodeRect = targetNode.getBoundingClientRect();
if (horizontal) {
return (event.pageX - targetNodeRect.left) < (targetNodeRect.width / 2);
}
else {
return (event.pageY - targetNodeRect.top) < (targetNodeRect.height / 2);
}
}
/**
* We use the position of the placeholder node to determine at which position of the array the
* object needs to be inserted
*/
function getPlaceholderIndex() {
return Array.prototype.indexOf.call(listNode.children, placeholderNode);
}
/**
* Checks various conditions that must be fulfilled for a drop to be allowed
*/
function isDropAllowed(event) {
// Disallow drop from external source unless it's allowed explicitly.
if (!dndDragTypeWorkaround.isDragging && !externalSources) return false;
// Check mimetype. Usually we would use a custom drag type instead of Text, but IE doesn't
// support that.
if (!hasTextMimetype(event.dataTransfer.types)) return false;
// Now check the dnd-allowed-types against the type of the incoming element. For drops from
// external sources we don't know the type, so it will need to be checked via dnd-drop.
if (attr.dndAllowedTypes && dndDragTypeWorkaround.isDragging) {
var allowed = scope.$eval(attr.dndAllowedTypes);
if (angular.isArray(allowed) && allowed.indexOf(dndDragTypeWorkaround.dragType) === -1) {
return false;
}
}
// Check whether droping is disabled completely
if (attr.dndDisableIf && scope.$eval(attr.dndDisableIf)) return false;
return true;
}
/**
* Small helper function that cleans up if we aborted a drop.
*/
function stopDragover() {
placeholder.remove();
element.removeClass("dndDragover");
return true;
}
/**
* Invokes a callback with some interesting parameters and returns the callbacks return value.
*/
function invokeCallback(expression, event, item) {
return $parse(expression)(scope, {
event: event,
index: getPlaceholderIndex(),
item: item || undefined,
external: !dndDragTypeWorkaround.isDragging,
type: dndDragTypeWorkaround.isDragging ? dndDragTypeWorkaround.dragType : undefined
});
}
/**
* Check if the dataTransfer object contains a drag type that we can handle. In old versions
* of IE the types collection will not even be there, so we just assume a drop is possible.
*/
function hasTextMimetype(types) {
if (!types) return true;
for (var i = 0; i < types.length; i++) {
if (types[i] === "Text" || types[i] === "text/plain") return true;
}
return false;
}
};
}])
/**
* This workaround handles the fact that Internet Explorer does not support drag types other than
* "Text" and "URL". That means we can not know whether the data comes from one of our elements or
* is just some other data like a text selection. As a workaround we save the isDragging flag in
* here. When a dropover event occurs, we only allow the drop if we are already dragging, because
* that means the element is ours.
*/
.factory('dndDragTypeWorkaround', function(){ return {} })
/**
* Chrome on Windows does not set the dropEffect field, which we need in dragend to determine
* whether a drag operation was successful. Therefore we have to maintain it in this global
* variable. The bug report for that has been open for years:
* https://code.google.com/p/chromium/issues/detail?id=39399
*/
.factory('dndDropEffectWorkaround', function(){ return {} });