Module

utils/dom/position

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

module

Filtering

Classes

Interfaces

  • Options

    The getOptimalPosition() helper options.

Type Definitions

  • PositioningFunction

    A positioning function which, based on positioned element and target Rects, returns rect coordinates representing the geometrical relation between them. Used by the getOptimalPosition helper.

Functions

  • getOptimalPosition( options ) → Position

    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

    The input data and configuration of the helper.

    Returns

    Position