A layout manager that arranges React components in multiple tab sets

Nov 04, 2018
A layout manager that arranges React components in multiple tab sets


FlexLayout is a layout manager that arranges React components in multiple tab sets, these can be resized and moved.

View Demo JSFiddle Demo Download Source


  • splitters
  • tabs
  • tab dragging and ordering
  • tabset dragging (move all the tabs in a tabset in one operation)
  • dock to tabset or edge of frame
  • maximize tabset (double click tabset header or use icon)
  • tab overflow (show menu when tabs overflow)
  • border tabsets
  • submodels, allow layouts inside layouts
  • tab renaming (double click tab text to rename)
  • themeing - light and dark
  • touch events - works on mobile devices (iPad, Android)
  • add tabs using drag, indirect drag, add to active tabset, add to tabset by id
  • preferred pixel size tabsets
  • headed tabsets
  • tab and tabset attributes: enableHeader, enableTabStrip, enableDock, enableDrop...
  • customizable tabs and tabset header rendering
  • esc cancels drag
  • typescript type declarations included
  • supports overriding css class names via the classNameMapper prop, for use in css modules


FlexLayout is in the npm repository. Simply install React and FlexLayout from npm:

npm install react --save npm install react-dom --save npm install flexlayout-react --save

Import React and FlexLayout in your modules:

import React from "react"; import ReactDOM from "react-dom"; import FlexLayout from "flexlayout-react";

Include the light or dark style in your html:

<link rel="stylesheet" href="node_modules/flexlayout-react/style/dark.css" />


The <Layout> component renders the tabsets and splitters, it takes the following props:

modelrequiredthe layout model
factoryrequireda factory function for creating React components
onActionoptionalfunction called whenever the layout generates an action to update the model (allows for intercepting actions before they are dispatched to the model, for example, asking the user to confirm a tab close)
onRenderTaboptionalfunction called when rendering a tab, allows leading (icon) and content sections to be customized
onRenderTabSetoptionalfunction called when rendering a tabset, allows header and buttons to be customized
onModelChangeoptionalfunction called when model has changed
classNameMapperoptionalfunction called with default css class name, return value is class name that will be used. Mainly for use with css modules.

The model is tree of Node objects that define the structure of the layout.

The factory is a function that takes a Node object and returns a React component that should be hosted by a tab in the layout.

The model can be created using the Model.fromJson(jsonObject) static method, and can be saved using the model.toJson() method.

this.state = {model: FlexLayout.Model.fromJson(json)}; render() { <Layout model={this.state.model} factory={factory}/> }

Example Configuration:

var json = { global: {}, borders: [], layout:{ "type": "row", "weight": 100, "children": [ { "type": "tabset", "weight": 50, "selected": 0, "children": [ { "type": "tab", "name": "FX", "component":"grid", } ] }, { "type": "tabset", "weight": 50, "selected": 0, "children": [ { "type": "tab", "name": "FI", "component":"grid", } ] } ] } };

Example Code

import React from "react"; import ReactDOM from "react-dom"; import FlexLayout from "flexlayout-react"; class Main extends React.Component { constructor(props) { super(props); this.state = {model: FlexLayout.Model.fromJson(json)}; } factory(node) { var component = node.getComponent(); if (component === "button") { return <button>{node.getName()}</button>; } } render() { return ( <FlexLayout.Layout model={this.state.model} factory={this.factory.bind(this)}/> ) } } ReactDOM.render(<Main/>, document.getElementById("container"));

(See the examples for full source code)

The above code would render two tabsets horizontally each containing a single tab that hosts a button component. The tabs could be moved and resized by dragging and dropping. Additional grids could be added to the layout by sending actions to the model.

Try it now using JSFiddle

The model is built up using 4 types of 'node':

  • row - rows contains a list of tabsets and child rows, the top level row will render horizontally, child 'rows' will render in the opposite orientation to their parent.

  • tabset - tabsets contain a list of tabs and the index of the selected tab

  • tab - tabs specify the name of the component that they should host (that will be loaded via the factory) and the text of the actual tab.

  • border - borders contain a list of tabs and the index of the selected tab, they can only be used in the borders
    top level element.

The main layout is defined with rows within rows that contain tabsets that themselves contain tabs.

The model json contains 3 top level elements:

  • global - where global options are defined
  • layout - where the main row/tabset/tabs layout hierarchy is defined
  • borders - (optional) where up to 4 borders are defined ("top", "bottom", "left", "right").

Weights on rows and tabsets specify the relative weight of these nodes within the parent row, the actual values do not matter just their relative values (ie two tabsets of weights 30,70 would render the same if they had weights of 3,7).

example borders section:

"borders": [ { "type":"border", "location": "left", "children": [ { "type": "tab", "enableClose":false, "name": "Navigation", "component": "grid", } ] }, { "type":"border", "location": "right", "children": [ { "type": "tab", "enableClose":false, "name": "Options", "component": "grid", } ] }, { "type":"border", "location": "bottom", "children": [ { "type": "tab", "enableClose":false, "name": "Activity Blotter", "component": "grid", }, { "type": "tab", "enableClose":false, "name": "Execution Blotter", "component": "grid", } ] } ]

To control where nodes can be dropped you can add a callback function to the model:



allowDrop(dragNode, dropInfo) { let dropNode = dropInfo.node; // prevent non-border tabs dropping into borders if (dropNode.getType() == "border" && (dragNode.getParent() == null || dragNode.getParent().getType() != "border")) return false; // prevent border tabs dropping into main layout if (dropNode.getType() != "border" && (dragNode.getParent() != null && dragNode.getParent().getType() == "border")) return false; return true; }

By changing global or node attributes you can change the layout appearance and functionality, for example:

Setting tabSetEnableTabStrip:false in the global options would change the layout into a multi-splitter (without
tabs or drag and drop).

global: {tabSetEnableTabStrip:false},

Global Config attributes

Attributes allowed in the 'global' element

tabDragSpeed0.3CSS transition speed of drag outlines (in seconds)

Row Attributes

Attributes allowed in nodes of type 'row'.

widthnullpreferred pixel width
heightnullpreferred pixel height
childrenrequireda list of row and tabset nodes

Tab Attributes

Attributes allowed in nodes of type 'tab'.

Inherited defaults will take their value from the associated global attributes (see above).

confignulla place to hold json config for the hosted component
idauto generated

Tab nodes have a getExtraData() method that initially returns an empty object, this is the place to
add extra data to a tab node that will not be saved.

TabSet Attributes

Attributes allowed in nodes of type 'tabset'.

Inherited defaults will take their value from the associated global attributes (see above).

Note: tabsets can be dynamically created as tabs are moved and deleted when all their tabs are removed (unless enableDeleteWhenEmpty is false).

widthnullpreferred pixel width
heightnullpreferred pixel height
namenullnamed tabsets will show a header bar above the tabs
idauto generated
childrenrequireda list of tab nodes

Border Attributes

Attributes allowed in nodes of type 'border'.

Inherited defaults will take their value from the associated global attributes (see above).

size200size of the tab body when selected
selected-1-1 is the unselected value
idauto generatedborder_ + border name e.g. border_left
showtrueshow/hide this border
childrenrequireda list of tab nodes

Model Actions

All changes to the model are applied through actions, you can intercept actions resulting from GUI changes before they are applied by
implementing the onAction callback property of the Layout. You can also apply actions directly using the Model.doAction()


model.doAction(Actions.updateModelAttributes({ splitterSize:40, tabSetHeaderHeight:40, tabSetTabStripHeight:40 }));

The above example would increase the size of the splitters, tabset headers and tabs, this could be used to make
adjusting the layout easier on a small device.

Action CreatorDescription
Actions.addNode(newNodeJson, toNodeId, location, index)add a new tab node to the given tabset node
Actions.moveNode(fromNodeId, toNodeId, location, index)move a tab node from its current location to the new node and location
Actions.deleteTab(tabNodeId)delete the given tab
Actions.selectTab(tabNodeId)select the given tab
Actions.setActiveTabset(tabsetNodeId)set the tabset as the active tabset
Actions.adjustSplit(splitterNodeId, value)adjust the size of the given splitter
Actions.maximizeToggle(tabsetNodeId)toggles whether the given tabset node is maximized
Actions.updateModelAttributes(attributes)updates the global attributes
Actions.updateNodeAttributes(nodeId, attributes)updates the attributes of the given node
Actions.adjustBorderSplit(borderNodeId, pos)updates the size of the given border node

for example:

model.doAction(Actions.addNode({type:"tab", component:"grid", name:"a grid", id:"5"}, "1", DropLocation.CENTER, 0));

This would add a new grid component to the center of tabset with id "1" and at the 0'th tab position (use value -1 to add to the end of the tabs).
Note: you can get the id of a node using the method node.getId(), if an id wasn't assigned when the node was created then one will be created for you of the form # (e.g. #1, #2 ...).

Layout Component Methods to Create New Tabs

Methods on the Layout Component for adding tabs, the tabs are specified by their layout json.


this.refs.layout.addTabToTabSet("NAVIGATION", {type:"tab", component:"grid", name:"a grid"});

This would add a new grid component to the tabset with id "NAVIGATION".

Layout MethodDescription
addTabToTabSet(tabsetId, json)adds a new tab to the tabset with the given Id
addTabToActiveTabSet(json)adds a new tab to the active tabset
addTabWithDragAndDrop(dragText, json, onDrop)adds a new tab by dragging a marker to the required location, the drag starts immediately
addTabWithDragAndDropIndirect(dragText, json, onDrop)adds a new tab by dragging a marker to the required location, the marker is shown and must be clicked on to start dragging

Tab Node Events

You can handle events on nodes by adding a listener, this would typically be done
in the components constructor() method.


constructor(props) { super(props); let config = this.props.node.getConfig(); // save state in flexlayout node tree this.props.node.setEventListener("save", function (p) { config.subject = this.subject; }.bind(this)); }
resizecalled when tab is resized during layout, called before it is rendered with the new size
closecalled when a tab is closed
visibilitycalled when the visibility of a tab changes
savecalled before a tabnode is serialized to json, use to save node config by adding data to the object returned by node.getConfig()

Building the Project

To compile the project just run webpack in the top level directory, this will compile and bundle flexlayout and the examples into
the bundles dir. Once compiled the examples can be run by opening their index.html files.

To build the npm distribution run 'npm run build', this will create the artifacts in the dist dir.