Module

utils/dom/position

@ckeditor/ckeditor5-utils/src/dom/position

module

Filtering

Interfaces

  • Options

    The getOptimalPosition() helper options.

Type Definitions

  • Position

    An object describing a position in position: absolute coordinate system, along with position name.

Functions

  • getOptimalPosition( options ) → Position

    static

    Calculates the position: absolute coordinates of a given element so it can be positioned with respect to the target in the visually most efficient way, taking various restrictions like viewport or limiter geometry into consideration.

    // The element which is to be positioned.
    const element = document.body.querySelector( '#toolbar' );
    
    // A target to which the element is positioned relatively.
    const target = document.body.querySelector( '#container' );
    
    // Finding the optimal coordinates for the positioning.
    const { left, top, name } = getOptimalPosition( {
        element: element,
        target: target,
    
        // The algorithm will chose among these positions to meet the requirements such
        // as "limiter" element or "fitInViewport", set below. The positions are considered
        // in the order of the array.
        positions: [
            //
             //    [ Target ]
            //    +-----------------+
            //    |     Element     |
            //    +-----------------+
            //
            targetRect => ( {
                top: targetRect.bottom,
                left: targetRect.left,
                name: 'mySouthEastPosition'
            } ),
    
            //
            //    +-----------------+
            //    |     Element     |
            //    +-----------------+
            //    [ Target ]
            //
            ( targetRect, elementRect ) => ( {
                top: targetRect.top - elementRect.height,
                left: targetRect.left,
                name: 'myNorthEastPosition'
            } )
        ],
    
        // Find a position such guarantees the element remains within visible boundaries of <body>.
        limiter: document.body,
    
        // Find a position such guarantees the element remains within visible boundaries of the browser viewport.
        fitInViewport: true
    } );
    
    // The best position which fits into document.body and the viewport. May be useful
    // to set proper class on the `element`.
    console.log( name ); // -> "myNorthEastPosition"
    
    // Using the absolute coordinates which has been found to position the element
    // as in the diagram depicting the "myNorthEastPosition" position.
    element.style.top = top;
    element.style.left = left;

    Parameters

    options : Options

    Positioning options object.

    Returns

    Position