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//
//  Licensed to the Apache Software Foundation (ASF) under one or more
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//  this work for additional information regarding copyright ownership.
//  The ASF licenses this file to You under the Apache License, Version 2.0
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//
//      http://www.apache.org/licenses/LICENSE-2.0
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//  distributed under the License is distributed on an "AS IS" BASIS,
//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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////////////////////////////////////////////////////////////////////////////////

package mx.core
{

/**
 *  The EdgeMetrics class specifies the thickness, in pixels,
 *  of the four edge regions around a visual component.
 *
 *  <p>The following Flex properties have values that are EdgeMetrics
 *  objects:</p>
 *
 *  <ul>
 *  <li>The <code>borderMetrics</code> property of the mx.core.Container and
 *  mx.skins.Border classes includes only the border in the calculations 
 *  of the property values of the EdgeMetrics object.</li>
 *
 *  <li>The <code>viewMetrics</code> property of the mx.core.Container
 *  class, and of subclasses of the Container class, includes possible 
 *  scrollbars and non-content elements -- such as a Panel container's
 *  header area and the area for a ControlBar component -- in the calculations
 *  of the  property values of the EdgeMetrics object.</li>
 *
 *  <li>The <code>viewMetricsAndPadding</code> property of the
 *  mx.core.Container class includes the items listed for the
 *  <code>viewMetrics</code> property, plus the any areas defined by 
 *  the margins of the container in the calculations of the 
 *  property values of the EdgeMetrics object.</li>
 *  </ul>
 *
 *  <p>These three properites all return a reference to the same
 *  EdgeMetrics object that the Container is using for its measurement
 *  and layout; they do not return a copy of this object.
 *  If you need a copy, call the <code>clone()</code> method.</p>
 *
 *  @see mx.core.Container
 *  @see mx.skins.Border
 *  @see mx.containers.Panel
 *  
 *  @langversion 3.0
 *  @playerversion Flash 9
 *  @playerversion AIR 1.1
 *  @productversion Flex 3
 */
public class EdgeMetrics
{
    include "../core/Version.as";

    //--------------------------------------------------------------------------
    //
    //  Class constants
    //
    //--------------------------------------------------------------------------

    /**
     *  An EdgeMetrics object with a value of zero for its
     *  <code>left</code>, <code>top</code>, <code>right</code>,
     *  and <code>bottom</code> properties.
     *  
     *  @langversion 3.0
     *  @playerversion Flash 9
     *  @playerversion AIR 1.1
     *  @productversion Flex 3
     */
    public static const EMPTY:EdgeMetrics = new EdgeMetrics(0, 0, 0, 0);

    //--------------------------------------------------------------------------
    //
    //  Constructor
    //
    //--------------------------------------------------------------------------

    /**
     *  Constructor.
     *
     *  @param left The width, in pixels, of the left edge region.
     *
     *  @param top The height, in pixels, of the top edge region.
     *
     *  @param right The width, in pixels, of the right edge region.
     *
     *  @param bottom The height, in pixels, of the bottom edge region.
     *  
     *  @langversion 3.0
     *  @playerversion Flash 9
     *  @playerversion AIR 1.1
     *  @productversion Flex 3
     */
    public function EdgeMetrics(left:Number = 0, top:Number = 0,
                                right:Number = 0, bottom:Number = 0)
    {
        super();

        this.left = left;
        this.top = top;
        this.right = right;
        this.bottom = bottom;
    }

    //--------------------------------------------------------------------------
    //
    //  Properties
    //
    //--------------------------------------------------------------------------

    //----------------------------------
    //  bottom
    //----------------------------------

    /**
     *  The height, in pixels, of the bottom edge region.
     *  
     *  @langversion 3.0
     *  @playerversion Flash 9
     *  @playerversion AIR 1.1
     *  @productversion Flex 3
     */
    public var bottom:Number;

    //----------------------------------
    //  left
    //----------------------------------

    /**
     *  The width, in pixels, of the left edge region.
     *  
     *  @langversion 3.0
     *  @playerversion Flash 9
     *  @playerversion AIR 1.1
     *  @productversion Flex 3
     */
    public var left:Number;

    //----------------------------------
    //  right
    //----------------------------------

    /**
     *  The width, in pixels, of the right edge region.
     *  
     *  @langversion 3.0
     *  @playerversion Flash 9
     *  @playerversion AIR 1.1
     *  @productversion Flex 3
     */
    public var right:Number;

    //----------------------------------
    //  top
    //----------------------------------

    /**
     *  The height, in pixels, of the top edge region.
     *  
     *  @langversion 3.0
     *  @playerversion Flash 9
     *  @playerversion AIR 1.1
     *  @productversion Flex 3
     */
    public var top:Number;

    //--------------------------------------------------------------------------
    //
    //  Methods
    //
    //--------------------------------------------------------------------------

    /**
     *  Returns a copy of this EdgeMetrics object.
     *
     *  @return A copy of this EdgeMetrics object.
     *  
     *  @langversion 3.0
     *  @playerversion Flash 9
     *  @playerversion AIR 1.1
     *  @productversion Flex 3
     */
    public function clone():EdgeMetrics
    {
        return new EdgeMetrics(left, top, right, bottom);
    }
}

}