displayOrder(val) {
      if (typeof val !== 'undefined') {
        displayOrder = val;
        return this;
      }
      return typeof displayOrder === 'function' ? displayOrder(callbackContext) : displayOrder;
    }
/**
     * The `displayOrder` property is used by the layout engine to lay out components.
     * Components are interpreted in the ascending order of the `displayOrder` value. The layout engine apply the value in two ways,
     * the first is the order in which components are rendererd. The second is the area components are laid out in
     * when they have a direction, i.e. docked to either top, bottom, left or right.
     *
     * If docked at the same area, the component with a higher `displayOrder` will be rendered
     * on top of the component with a lower `displayOrder`. It can be seen as defining a z-index.
     * A lower `displayOrder` also means that a component will be laid out first in a given direction,
     * i.e. laid out closer to the central area (non-directional area) then a component with a higher `displayOrder`.
     * It can in this case be seen as the x-index or y-index.
     * @param {number} [val=0] - The display order
     * @returns {this|number} The current context or display order
     * @example
     * dockConfig.displayOrder(99);
     */
The `displayOrder` property is used by the layout engine to lay out components.
Components are interpreted in the ascending order of the `displayOrder` value. The layout engine apply the value in two ways,
the first is the order in which components are rendererd. The second is the area components are laid out in
when they have a direction, i.e. docked to either top, bottom, left or right.

If docked at the same area, the component with a higher `displayOrder` will be rendered
on top of the component with a lower `displayOrder`. It can be seen as defining a z-index.
A lower `displayOrder` also means that a component will be laid out first in a given direction,
i.e. laid out closer to the central area (non-directional area) then a component with a higher `displayOrder`.
It can in this case be seen as the x-index or y-index.
@param {number} [val=0] - The display order
@returns {this|number} The current context or display order
@example
dockConfig.displayOrder(99).
The ` displayOrder ` property is used by the layout engine to lay out components . Components are interpreted in the ascending order of the ` displayOrder ` value . The layout engine apply the value in two ways the first is the order in which components are rendererd . The second is the area components are laid out in when they have a direction i . e . docked to either top bottom left or right . If docked at the same area the component with a higher ` displayOrder ` will be rendered on top of the component with a lower ` displayOrder ` . It can be seen as defining a z - index . A lower ` displayOrder ` also means that a component will be laid out first in a given direction i . e . laid out closer to the central area ( non - directional area ) then a component with a higher ` displayOrder ` . It can in this case be seen as the x - index or y - index . @param { number } [ val = 0 ] - The display order @returns { this|number } The current context or display order @example dockConfig . displayOrder ( 99 ) .
displayOrder(val) {
      if (typeof val !== 'undefined') {
        displayOrder = val;
        return this;
      }
      return typeof displayOrder === 'function' ? displayOrder(callbackContext) : displayOrder;
    }
displayOrder ( val ) { if ( typeof val !== 'undefined' ) { displayOrder = val ; return this ; } return typeof displayOrder === 'function' ? displayOrder ( callbackContext ) : displayOrder ; }
The `displayOrder` property is used by the layout engine to lay out components.
The ` displayOrder ` property is used by the layout engine to lay out components .