ddcore.js

一个struts和extjs得源码

     * id this was hovering over.  In INTERSECT mode, an array of dd items
     * that the mouse is no longer over.
     */
    onDragOut: function(e, id) { /* override this */ },

    /**
     * Code that executes immediately before the onDragDrop event
     * @method b4DragDrop
     * @private
     */
    b4DragDrop: function(e) { },

    /**
     * Abstract method called when this item is dropped on another DragDrop
     * obj
     * @method onDragDrop
     * @param {Event} e the mouseup event
     * @param {String|DragDrop[]} id In POINT mode, the element
     * id this was dropped on.  In INTERSECT mode, an array of dd items this
     * was dropped on.
     */
    onDragDrop: function(e, id) { /* override this */ },

    /**
     * Abstract method called when this item is dropped on an area with no
     * drop target
     * @method onInvalidDrop
     * @param {Event} e the mouseup event
     */
    onInvalidDrop: function(e) { /* override this */ },

    /**
     * Code that executes immediately before the endDrag event
     * @method b4EndDrag
     * @private
     */
    b4EndDrag: function(e) { },

    /**
     * Fired when we are done dragging the object
     * @method endDrag
     * @param {Event} e the mouseup event
     */
    endDrag: function(e) { /* override this */ },

    /**
     * Code executed immediately before the onMouseDown event
     * @method b4MouseDown
     * @param {Event} e the mousedown event
     * @private
     */
    b4MouseDown: function(e) {  },

    /**
     * Event handler that fires when a drag/drop obj gets a mousedown
     * @method onMouseDown
     * @param {Event} e the mousedown event
     */
    onMouseDown: function(e) { /* override this */ },

    /**
     * Event handler that fires when a drag/drop obj gets a mouseup
     * @method onMouseUp
     * @param {Event} e the mouseup event
     */
    onMouseUp: function(e) { /* override this */ },

    /**
     * Override the onAvailable method to do what is needed after the initial
     * position was determined.
     * @method onAvailable
     */
    onAvailable: function () {
    },

    /**
     * Provides default constraint padding to "constrainTo" elements (defaults to {left: 0, right:0, top:0, bottom:0}).
     * @type Object
     */
    defaultPadding : {left:0, right:0, top:0, bottom:0},

    /**
     * Initializes the drag drop object's constraints to restrict movement to a certain element.
 *
 * Usage:
 <pre><code>
 var dd = new Ext.dd.DDProxy("dragDiv1", "proxytest",
                { dragElId: "existingProxyDiv" });
 dd.startDrag = function(){
     this.constrainTo("parent-id");
 };
 </code></pre>
 * Or you can initalize it using the {@link Ext.Element} object:
 <pre><code>
 Ext.get("dragDiv1").initDDProxy("proxytest", {dragElId: "existingProxyDiv"}, {
     startDrag : function(){
         this.constrainTo("parent-id");
     }
 });
 </code></pre>
     * @param {Mixed} constrainTo The element to constrain to.
     * @param {Object/Number} pad (optional) Pad provides a way to specify "padding" of the constraints,
     * and can be either a number for symmetrical padding (4 would be equal to {left:4, right:4, top:4, bottom:4}) or
     * an object containing the sides to pad. For example: {right:10, bottom:10}
     * @param {Boolean} inContent (optional) Constrain the draggable in the content box of the element (inside padding and borders)
     */
    constrainTo : function(constrainTo, pad, inContent){
        if(typeof pad == "number"){
            pad = {left: pad, right:pad, top:pad, bottom:pad};
        }
        pad = pad || this.defaultPadding;
        var b = Ext.get(this.getEl()).getBox();
        var ce = Ext.get(constrainTo);
        var s = ce.getScroll();
        var c, cd = ce.dom;
        if(cd == document.body){
            c = { x: s.left, y: s.top, width: Ext.lib.Dom.getViewWidth(), height: Ext.lib.Dom.getViewHeight()};
        }else{
            var xy = ce.getXY();
            c = {x : xy[0]+s.left, y: xy[1]+s.top, width: cd.clientWidth, height: cd.clientHeight};
        }


        var topSpace = b.y - c.y;
        var leftSpace = b.x - c.x;

        this.resetConstraints();
        this.setXConstraint(leftSpace - (pad.left||0), // left
                c.width - leftSpace - b.width - (pad.right||0), //right
				this.xTickSize
        );
        this.setYConstraint(topSpace - (pad.top||0), //top
                c.height - topSpace - b.height - (pad.bottom||0), //bottom
				this.yTickSize
        );
    },

    /**
     * Returns a reference to the linked element
     * @method getEl
     * @return {HTMLElement} the html element
     */
    getEl: function() {
        if (!this._domRef) {
            this._domRef = Ext.getDom(this.id);
        }

        return this._domRef;
    },

    /**
     * Returns a reference to the actual element to drag.  By default this is
     * the same as the html element, but it can be assigned to another
     * element. An example of this can be found in Ext.dd.DDProxy
     * @method getDragEl
     * @return {HTMLElement} the html element
     */
    getDragEl: function() {
        return Ext.getDom(this.dragElId);
    },

    /**
     * Sets up the DragDrop object.  Must be called in the constructor of any
     * Ext.dd.DragDrop subclass
     * @method init
     * @param id the id of the linked element
     * @param {String} sGroup the group of related items
     * @param {object} config configuration attributes
     */
    init: function(id, sGroup, config) {
        this.initTarget(id, sGroup, config);
        Event.on(this.id, "mousedown", this.handleMouseDown, this);
        // Event.on(this.id, "selectstart", Event.preventDefault);
    },

    /**
     * Initializes Targeting functionality only... the object does not
     * get a mousedown handler.
     * @method initTarget
     * @param id the id of the linked element
     * @param {String} sGroup the group of related items
     * @param {object} config configuration attributes
     */
    initTarget: function(id, sGroup, config) {

        // configuration attributes
        this.config = config || {};

        // create a local reference to the drag and drop manager
        this.DDM = Ext.dd.DDM;
        // initialize the groups array
        this.groups = {};

        // assume that we have an element reference instead of an id if the
        // parameter is not a string
        if (typeof id !== "string") {
            id = Ext.id(id);
        }

        // set the id
        this.id = id;

        // add to an interaction group
        this.addToGroup((sGroup) ? sGroup : "default");

        // We don't want to register this as the handle with the manager
        // so we just set the id rather than calling the setter.
        this.handleElId = id;

        // the linked element is the element that gets dragged by default
        this.setDragElId(id);

        // by default, clicked anchors will not start drag operations.
        this.invalidHandleTypes = { A: "A" };
        this.invalidHandleIds = {};
        this.invalidHandleClasses = [];

        this.applyConfig();

        this.handleOnAvailable();
    },

    /**
     * Applies the configuration parameters that were passed into the constructor.
     * This is supposed to happen at each level through the inheritance chain.  So
     * a DDProxy implentation will execute apply config on DDProxy, DD, and
     * DragDrop in order to get all of the parameters that are available in
     * each object.
     * @method applyConfig
     */
    applyConfig: function() {

        // configurable properties:
        //    padding, isTarget, maintainOffset, primaryButtonOnly
        this.padding           = this.config.padding || [0, 0, 0, 0];
        this.isTarget          = (this.config.isTarget !== false);
        this.maintainOffset    = (this.config.maintainOffset);
        this.primaryButtonOnly = (this.config.primaryButtonOnly !== false);

    },

    /**
     * Executed when the linked element is available
     * @method handleOnAvailable
     * @private
     */
    handleOnAvailable: function() {
        this.available = true;
        this.resetConstraints();
        this.onAvailable();
    },

     /**
     * Configures the padding for the target zone in px.  Effectively expands
     * (or reduces) the virtual object size for targeting calculations.
     * Supports css-style shorthand; if only one parameter is passed, all sides
     * will have that padding, and if only two are passed, the top and bottom
     * will have the first param, the left and right the second.
     * @method setPadding
     * @param {int} iTop    Top pad
     * @param {int} iRight  Right pad
     * @param {int} iBot    Bot pad
     * @param {int} iLeft   Left pad
     */
    setPadding: function(iTop, iRight, iBot, iLeft) {
        // this.padding = [iLeft, iRight, iTop, iBot];
        if (!iRight && 0 !== iRight) {
            this.padding = [iTop, iTop, iTop, iTop];
        } else if (!iBot && 0 !== iBot) {
            this.padding = [iTop, iRight, iTop, iRight];
        } else {
            this.padding = [iTop, iRight, iBot, iLeft];
        }
    },

    /**
     * Stores the initial placement of the linked element.
     * @method setInitialPosition
     * @param {int} diffX   the X offset, default 0
     * @param {int} diffY   the Y offset, default 0
     */
    setInitPosition: function(diffX, diffY) {
        var el = this.getEl();

        if (!this.DDM.verifyEl(el)) {
            return;
        }

        var dx = diffX || 0;
        var dy = diffY || 0;

        var p = Dom.getXY( el );

        this.initPageX = p[0] - dx;
        this.initPageY = p[1] - dy;

        this.lastPageX = p[0];
        this.lastPageY = p[1];


        this.setStartPosition(p);
    },

    /**
     * Sets the start position of the element.  This is set when the obj
     * is initialized, the reset when a drag is started.
     * @method setStartPosition
     * @param pos current position (from previous lookup)
     * @private
     */
    setStartPosition: function(pos) {
        var p = pos || Dom.getXY( this.getEl() );
        this.deltaSetXY = null;

        this.startPageX = p[0];
        this.startPageY = p[1];
    },

    /**
     * Add this instance to a group of related drag/drop objects.  All
     * instances belong to at least one group, and can belong to as many
     * groups as needed.
     * @method addToGroup
     * @param sGroup {string} the name of the group
     */
    addToGroup: function(sGroup) {
        this.groups[sGroup] = true;
        this.DDM.regDragDrop(this, sGroup);
    },

    /**
     * Remove's this instance from the supplied interaction group
     * @method removeFromGroup
     * @param {string}  sGroup  The group to drop
     */
    removeFromGroup: function(sGroup) {
        if (this.groups[sGroup]) {
            delete this.groups[sGroup];
        }

        this.DDM.removeDDFromGroup(this, sGroup);
    },

    /**
     * Allows you to specify that an element other than the linked element
     * will be moved with the cursor during a drag
     * @method setDragElId
     * @param id {string} the id of the element that will be used to initiate the drag
     */
    setDragElId: function(id) {
        this.dragElId = id;
    },

    /**
     * Allows you to specify a child of the linked element that should be
     * used to initiate the drag operation.  An example of this would be if
     * you have a content div with text and links.  Clicking anywhere in the
     * content area would normally start the drag operation.  Use this method
     * to specify that an element inside of the content div is the element
     * that starts the drag operation.
     * @method setHandleElId
     * @param id {string} the id of the element that will be used to
     * initiate the drag.
     */
    setHandleElId: function(id) {
        if (typeof id !== "string") {
            id = Ext.id(id);
        }
        this.handleElId = id;
        this.DDM.regHandle(this.id, id);
    },

    /**
     * Allows you to set an element outside of the linked element as a drag
     * handle
     * @method setOuterHandleElId
     * @param id the id of the element that will be used to initiate the drag
     */
    setOuterHandleElId: function(id) {
        if (typeof id !== "string") {
            id = Ext.id(id);
        }
        Event.on(id, "mousedown",
                this.handleMouseDown, this);
        this.setHandleElId(id);

        this.hasOuterHandles = true;
    },

    /**
     * Remove all drag and drop hooks for this element
     * @method unreg
     */
    unreg: function() {
        Event.un(this.id, "mousedown",
                this.handleMouseDown);
        this._domRef = null;
        this.DDM._remove(this);
    },

    destroy : function(){
        this.unreg();
    },

    /**
     * Returns true if this instance is locked, or the drag drop mgr is locked
     * (meaning that all drag/drop is disabled on the page.)
     * @method isLocked