diff options
Diffstat (limited to 'components/newtab/dropTargetShim.js')
-rw-r--r-- | components/newtab/dropTargetShim.js | 232 |
1 files changed, 0 insertions, 232 deletions
diff --git a/components/newtab/dropTargetShim.js b/components/newtab/dropTargetShim.js deleted file mode 100644 index 57a97fa..0000000 --- a/components/newtab/dropTargetShim.js +++ /dev/null @@ -1,232 +0,0 @@ -#ifdef 0 -/* This Source Code Form is subject to the terms of the Mozilla Public - * License, v. 2.0. If a copy of the MPL was not distributed with this file, - * You can obtain one at http://mozilla.org/MPL/2.0/. */ -#endif - -/** - * This singleton provides a custom drop target detection. We need this because - * the default DnD target detection relies on the cursor's position. We want - * to pick a drop target based on the dragged site's position. - */ -var gDropTargetShim = { - /** - * Cache for the position of all cells, cleaned after drag finished. - */ - _cellPositions: null, - - /** - * The last drop target that was hovered. - */ - _lastDropTarget: null, - - /** - * Initializes the drop target shim. - */ - init: function () { - gGrid.node.addEventListener("dragstart", this, true); - }, - - /** - * Add all event listeners needed during a drag operation. - */ - _addEventListeners: function () { - gGrid.node.addEventListener("dragend", this); - - let docElement = document.documentElement; - docElement.addEventListener("dragover", this); - docElement.addEventListener("dragenter", this); - docElement.addEventListener("drop", this); - }, - - /** - * Remove all event listeners that were needed during a drag operation. - */ - _removeEventListeners: function () { - gGrid.node.removeEventListener("dragend", this); - - let docElement = document.documentElement; - docElement.removeEventListener("dragover", this); - docElement.removeEventListener("dragenter", this); - docElement.removeEventListener("drop", this); - }, - - /** - * Handles all shim events. - */ - handleEvent: function (aEvent) { - switch (aEvent.type) { - case "dragstart": - this._dragstart(aEvent); - break; - case "dragenter": - aEvent.preventDefault(); - break; - case "dragover": - this._dragover(aEvent); - break; - case "drop": - this._drop(aEvent); - break; - case "dragend": - this._dragend(aEvent); - break; - } - }, - - /** - * Handles the 'dragstart' event. - * @param aEvent The 'dragstart' event. - */ - _dragstart: function (aEvent) { - if (aEvent.target.classList.contains("newtab-link")) { - gGrid.lock(); - this._addEventListeners(); - } - }, - - /** - * Handles the 'dragover' event. - * @param aEvent The 'dragover' event. - */ - _dragover: function (aEvent) { - // XXX bug 505521 - Use the dragover event to retrieve the - // current mouse coordinates while dragging. - let sourceNode = aEvent.dataTransfer.mozSourceNode.parentNode; - gDrag.drag(sourceNode._newtabSite, aEvent); - - // Find the current drop target, if there's one. - this._updateDropTarget(aEvent); - - // If we have a valid drop target, - // let the drag-and-drop service know. - if (this._lastDropTarget) { - aEvent.preventDefault(); - } - }, - - /** - * Handles the 'drop' event. - * @param aEvent The 'drop' event. - */ - _drop: function (aEvent) { - // We're accepting all drops. - aEvent.preventDefault(); - - // remember that drop event was seen, this explicitly - // assumes that drop event preceeds dragend event - this._dropSeen = true; - - // Make sure to determine the current drop target - // in case the dragover event hasn't been fired. - this._updateDropTarget(aEvent); - - // A site was successfully dropped. - this._dispatchEvent(aEvent, "drop", this._lastDropTarget); - }, - - /** - * Handles the 'dragend' event. - * @param aEvent The 'dragend' event. - */ - _dragend: function (aEvent) { - if (this._lastDropTarget) { - if (aEvent.dataTransfer.mozUserCancelled || !this._dropSeen) { - // The drag operation was cancelled or no drop event was generated - this._dispatchEvent(aEvent, "dragexit", this._lastDropTarget); - this._dispatchEvent(aEvent, "dragleave", this._lastDropTarget); - } - - // Clean up. - this._lastDropTarget = null; - this._cellPositions = null; - } - - this._dropSeen = false; - gGrid.unlock(); - this._removeEventListeners(); - }, - - /** - * Tries to find the current drop target and will fire - * appropriate dragenter, dragexit, and dragleave events. - * @param aEvent The current drag event. - */ - _updateDropTarget: function (aEvent) { - // Let's see if we find a drop target. - let target = this._findDropTarget(aEvent); - - if (target != this._lastDropTarget) { - if (this._lastDropTarget) - // We left the last drop target. - this._dispatchEvent(aEvent, "dragexit", this._lastDropTarget); - - if (target) - // We're now hovering a (new) drop target. - this._dispatchEvent(aEvent, "dragenter", target); - - if (this._lastDropTarget) - // We left the last drop target. - this._dispatchEvent(aEvent, "dragleave", this._lastDropTarget); - - this._lastDropTarget = target; - } - }, - - /** - * Determines the current drop target by matching the dragged site's position - * against all cells in the grid. - * @return The currently hovered drop target or null. - */ - _findDropTarget: function () { - // These are the minimum intersection values - we want to use the cell if - // the site is >= 50% hovering its position. - let minWidth = gDrag.cellWidth / 2; - let minHeight = gDrag.cellHeight / 2; - - let cellPositions = this._getCellPositions(); - let rect = gTransformation.getNodePosition(gDrag.draggedSite.node); - - // Compare each cell's position to the dragged site's position. - for (let i = 0; i < cellPositions.length; i++) { - let inter = rect.intersect(cellPositions[i].rect); - - // If the intersection is big enough we found a drop target. - if (inter.width >= minWidth && inter.height >= minHeight) - return cellPositions[i].cell; - } - - // No drop target found. - return null; - }, - - /** - * Gets the positions of all cell nodes. - * @return The (cached) cell positions. - */ - _getCellPositions: function DropTargetShim_getCellPositions() { - if (this._cellPositions) - return this._cellPositions; - - return this._cellPositions = gGrid.cells.map(function (cell) { - return {cell: cell, rect: gTransformation.getNodePosition(cell.node)}; - }); - }, - - /** - * Dispatches a custom DragEvent on the given target node. - * @param aEvent The source event. - * @param aType The event type. - * @param aTarget The target node that receives the event. - */ - _dispatchEvent: function (aEvent, aType, aTarget) { - let node = aTarget.node; - let event = document.createEvent("DragEvent"); - - // The event should not bubble to prevent recursion. - event.initDragEvent(aType, false, true, window, 0, 0, 0, 0, 0, false, false, - false, false, 0, node, aEvent.dataTransfer); - - node.dispatchEvent(event); - } -}; |