getRegionFlowRanges()
Summary
Returns a series of Range objects that represent the fragments of DOM content that currently flow into the region.
Method of apis/css-regions/Regionapis/css-regions/Region
Syntax
var ranges = region.getRegionFlowRanges();
Return Value
Returns an object of type ArrayArray
Returns a series of Range objects that represent the fragments of DOM content that currently flow into the region.
Examples
Check a region for interruptions in source content:
// get flow
var flow = document.getNamedFlows().namedItem('main');
// get second region that displays content
var region = flow.getRegions()[1];
// how many content fragments display there?
var ranges = region.getRegionFlowRanges();
// perhaps do something to fix layout if content has been interrupted:
if (ranges.length > 1) {
adjustlayout(region) // custom function
}
Usage
By default, calling getRegionFlowRanges() on an overflowing region at the end of a chain (one whose regionOverset is overset) returns fragments representing all remaining content that may overflow out of view. If the region's region-fragment property is set to break, it returns only those fragments of content that fit neatly within the region.
If the region is too small to display the content, it returns a single collapsed range.
Calling it on an empty region (one whose regionOverset is empty) returns an empty list.
Calling it on an element that is no longer a region (when its flow-from property reverts to none) returns null. The following tests whether the block element currently behaves as a region:
isRegion = (element.getRegionFlowRanges() !== null);
Notes
Regions may display more than one range, because more than one element may specify flow-into to contribute to a flow, and the boundary between those content elements may fall within a region. Also, any content element’s nested elements can be diverted to a different named flow, thus interrupting the original sequence of content. (See flow-into for more details on these scenarios.)
Related specifications
- CSS Regions Module Level 1
- W3C Working Draft
See also
Related articles
Regions
getRegionFlowRanges()
External resources
- W3C editor’s draft: CSS Regions Module Level 3
- Adobe Web Standards: CSS Regions
- Adobe Developer’s Network: CSS3 Regions: Rich page layout with HTML and CSS3
- Sample pages