element.position.js

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/*
 * Ext JS Library 3.0 Pre-alpha
 * Copyright(c) 2006-2008, Ext JS, LLC.
 * [e-mail]
 * 
 * http://extjs.com/license
 */

/**
 * @class Ext.Element
 */
(function(){
var D = Ext.lib.Dom;

function animTest(args, animate, i) {
	return this.preanim && !!animate ? this.preanim(args, i) : false	
}

Ext.Element.addMethods({
	/**
      * Gets the current X position of the element based on page coordinates.  Element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
      * @return {Number} The X position of the element
      */
    getX : function(){
        return D.getX(this.dom);
    },

    /**
      * Gets the current Y position of the element based on page coordinates.  Element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
      * @return {Number} The Y position of the element
      */
    getY : function(){
        return D.getY(this.dom);
    },

    /**
      * Gets the current position of the element based on page coordinates.  Element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
      * @return {Array} The XY position of the element
      */
    getXY : function(){
        return D.getXY(this.dom);
    },

    /**
      * Returns the offsets of this element from the passed element. Both element must be part of the DOM tree and not have display:none to have page coordinates.
      * @param {Mixed} element The element to get the offsets from.
      * @return {Array} The XY page offsets (e.g. [100, -200])
      */
    getOffsetsTo : function(el){
        var o = this.getXY(),
        	e = Ext.fly(el, '_internal').getXY();
        return [o[0]-e[0],o[1]-e[1]];
    },

    /**
     * Sets the X position of the element based on page coordinates.  Element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
     * @param {Number} The X position of the element
     * @param {Boolean/Object} animate (optional) True for the default animation, or a standard Element animation config object
     * @return {Ext.Element} this
     */
    setX : function(x, animate){	    
	    return this.setXY([x, this.getY()], animTest.call(this, arguments, animate, 1));
    },

    /**
     * Sets the Y position of the element based on page coordinates.  Element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
     * @param {Number} The Y position of the element
     * @param {Boolean/Object} animate (optional) True for the default animation, or a standard Element animation config object
     * @return {Ext.Element} this
     */
    setY : function(y, animate){	    
	    return this.setXY([this.getX(), y], animTest.call(this, arguments, animate, 1));
    },

    /**
     * Sets the element's left position directly using CSS style (instead of {@link #setX}).
     * @param {String} left The left CSS property value
     * @return {Ext.Element} this
     */
    setLeft : function(left){
        this.setStyle("left", this.addUnits(left));
        return this;
    },

    /**
     * Sets the element's top position directly using CSS style (instead of {@link #setY}).
     * @param {String} top The top CSS property value
     * @return {Ext.Element} this
     */
    setTop : function(top){
        this.setStyle("top", this.addUnits(top));
        return this;
    },

    /**
     * Sets the element's CSS right style.
     * @param {String} right The right CSS property value
     * @return {Ext.Element} this
     */
    setRight : function(right){
        this.setStyle("right", this.addUnits(right));
        return this;
    },

    /**
     * Sets the element's CSS bottom style.
     * @param {String} bottom The bottom CSS property value
     * @return {Ext.Element} this
     */
    setBottom : function(bottom){
        this.setStyle("bottom", this.addUnits(bottom));
        return this;
    },

    /**
     * Sets the position of the element in page coordinates, regardless of how the element is positioned.
     * The element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
     * @param {Array} pos Contains X & Y [x, y] values for new position (coordinates are page-based)
     * @param {Boolean/Object} animate (optional) True for the default animation, or a standard Element animation config object
     * @return {Ext.Element} this
     */
    setXY : function(pos, animate){
	    var me = this;
        if(!animate || !me.anim){
            D.setXY(me.dom, pos);
        }else{
            me.anim({points: {to: pos}}, me.preanim(arguments, 1), 'motion');
        }
        return me;
    },

    /**
     * Sets the position of the element in page coordinates, regardless of how the element is positioned.
     * The element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
     * @param {Number} x X value for new position (coordinates are page-based)
     * @param {Number} y Y value for new position (coordinates are page-based)
     * @param {Boolean/Object} animate (optional) True for the default animation, or a standard Element animation config object
     * @return {Ext.Element} this
     */
    setLocation : function(x, y, animate){
        return this.setXY([x, y], animTest.call(this, arguments, animate, 2));
    },

    /**
     * Sets the position of the element in page coordinates, regardless of how the element is positioned.
     * The element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
     * @param {Number} x X value for new position (coordinates are page-based)
     * @param {Number} y Y value for new position (coordinates are page-based)
     * @param {Boolean/Object} animate (optional) True for the default animation, or a standard Element animation config object
     * @return {Ext.Element} this
     */
    moveTo : function(x, y, animate){
        return this.setXY([x, y], animTest.call(this, arguments, animate, 2));        
    },    
    
    /**
     * Gets the left X coordinate
     * @param {Boolean} local True to get the local css position instead of page coordinate
     * @return {Number}
     */
    getLeft : function(local){
	    return !local ? this.getX() : parseInt(this.getStyle("left"), 10) || 0;
    },

    /**
     * Gets the right X coordinate of the element (element X position + element width)
     * @param {Boolean} local True to get the local css position instead of page coordinate
     * @return {Number}
     */
    getRight : function(local){
	    var me = this;
	    return !local ? me.getX() + me.getWidth() : (me.getLeft(true) + me.getWidth()) || 0;
    },

    /**
     * Gets the top Y coordinate
     * @param {Boolean} local True to get the local css position instead of page coordinate
     * @return {Number}
     */
    getTop : function(local) {
	    return !local ? this.getY() : parseInt(this.getStyle("top"), 10) || 0;
    },

    /**
     * Gets the bottom Y coordinate of the element (element Y position + element height)
     * @param {Boolean} local True to get the local css position instead of page coordinate
     * @return {Number}
     */
    getBottom : function(local){
	    var me = this;
	    return !local ? me.getY() + me.getHeight() : (me.getTop(true) + me.getHeight()) || 0;
    },

    /**
    * Initializes positioning on this element. If a desired position is not passed, it will make the
    * the element positioned relative IF it is not already positioned.
    * @param {String} pos (optional) Positioning to use "relative", "absolute" or "fixed"
    * @param {Number} zIndex (optional) The zIndex to apply
    * @param {Number} x (optional) Set the page X position
    * @param {Number} y (optional) Set the page Y position
    */
    position : function(pos, zIndex, x, y){
	    var me = this;
	    
        if(!pos && me.isStyle('position', 'static')){           
            me.setStyle('position', 'relative');           
        } else if(pos) {
            me.setStyle("position", pos);
        }
        if(zIndex){
            me.setStyle("z-index", zIndex);
        }
        if(x || y) me.setXY([x || false, y || false]);
    },

    /**
    * Clear positioning back to the default when the document was loaded
    * @param {String} value (optional) The value to use for the left,right,top,bottom, defaults to '' (empty string). You could use 'auto'.
    * @return {Ext.Element} this
     */
    clearPositioning : function(value){
        value = value || '';
        this.setStyle({
            left : value,
            right : value,
            top : value,
            bottom : value,
            "z-index" : "",
            position : "static"
        });
        return this;
    },

    /**
    * Gets an object with all CSS positioning properties. Useful along with setPostioning to get
    * snapshot before performing an update and then restoring the element.
    * @return {Object}
    */
    getPositioning : function(){
	    var me = this;
        function gs(pos) {
	    	return me.getStyle(pos);    
        }
        
        var l = gs("left"),
        	t = gs("top");

        return {
            position : gs("position"),
            left : l,
            right : l ? "" : gs("right"),
            top : t,
            bottom : t ? "" : gs("bottom"),
            "z-index" : gs("z-index")
        };
    },
    
    /**
    * Set positioning with an object returned by getPositioning().
    * @param {Object} posCfg
    * @return {Ext.Element} this
     */
    setPositioning : function(pc){
	    var me = this,
	    	style = me.dom.style;
	    	
        me.setStyle(pc);
        
        if(pc.right == "auto"){
            style.right = "";
        }
        if(pc.bottom == "auto"){
            style.bottom = "";
        }
        
        return me;
    },    
	
    /**
     * Translates the passed page coordinates into left/top css values for this element
     * @param {Number/Array} x The page x or an array containing [x, y]
     * @param {Number} y (optional) The page y, required if x is not an array
     * @return {Object} An object with left and top properties. e.g. {left: (value), top: (value)}
     */
    translatePoints : function(x, y){        	     
	    y = isNaN(x[1]) ? y : x[1];
        x = isNaN(x[0]) ? x : x[0];
        var me = this,
        	relative = me.isStyle('position', "relative"),
        	o = me.getXY(),
        	l = parseInt(me.getStyle('left'), 10),
        	t = parseInt(me.getStyle('top'), 10);
        
        l = !isNaN(l) ? l : (relative ? 0 : me.dom.offsetLeft);
        t = !isNaN(t) ? t : (relative ? 0 : me.dom.offsetTop);        

        return {left: (x - o[0] + l), top: (y - o[1] + t)}; 
    },
    
    animTest : animTest
});
})();