Link tools
JointJS allows creating fully customizable user interaction tools for your links. These tools show up on user interaction (e.g. mouseover) with a link view and allow the user to interact with the underlying link model. For example:
The process of getting link tools up and running on your link view is relatively straightforward:
- Create individual link tools.
- Add the link tools to a toolsView.
- Add the toolsView to a link view.
- Make the tools interactive.
We will explain every step in turn. We will also touch on creating custom buttons.
Creating a link toolβ
A link tool (type dia.ToolView
) is a view that renders a certain type of control elements on top of the link view it is attached to; for example the Vertices
tool creates an interactive handle above every vertex (these handles then allow the user to move and/or delete each vertex). The JointJS library comes with a collection of pre-made link tool definitions in the linkTools
namespace.
The pre-made link tools include:
Vertices
- adds handles above link verticesSegments
- adds handles above link segmentsSourceArrowhead
- adds a handle above link source connection pointTargetArrowhead
- adds a handle above link target connection pointSourceAnchor
- adds a handle above link source anchorTargetAnchor
- adds a handle above link target anchorBoundary
- shows the bounding box of the linkRemove
- adds an interactive remove button
To create a new link tool, we call its constructor:
import { linkTools } from '@joint/core';
const verticesTool = new linkTools.Vertices();
The link tool constructors also accept optional arguments that modify the appearance and function of the created tools:
import { linkTools } from '@joint/core';
const verticesTool = new linkTools.Vertices({
redundancyRemoval: false,
snapRadius: 10,
vertexAdding: false,
});
Add to tools viewβ
Link tools always need to come bundled in a tools view object (type dia.ToolsView
). This allows them to be shown/hidden as a group above a link. We create a new tools view and add our tools to it:
const verticesTool = new linkTools.Vertices();
const segmentsTool = new linkTools.Segments();
const sourceArrowheadTool = new linkTools.SourceArrowhead();
const targetArrowheadTool = new linkTools.TargetArrowhead();
const sourceAnchorTool = new linkTools.SourceAnchor();
const targetAnchorTool = new linkTools.TargetAnchor();
const boundaryTool = new linkTools.Boundary();
const removeButton = new linkTools.Remove();
const toolsView = new dia.ToolsView({
tools: [
verticesTool, segmentsTool,
sourceArrowheadTool, targetArrowheadTool,
sourceAnchorTool, targetAnchorTool,
boundaryTool, removeButton
]
});
Remember, it is necessary to create a new set of tools for every new tools view object we create; tools are automatically reassigned to the last tools view that uses them.
Add to Link Viewβ
Finally, we need to add our tools view to a link view. The dia.LinkView
class comes with a suite of tools-related methods:
linkView.addTools(toolsView)
- adds giventoolsView
onto the link view. The tools are visible by default.linkView.showTools()
- shows tools on the link view.linkView.hideTools()
- hides tools on the link view.linkView.removeTools()
- removes tools from the link view.
We can thus show all of our tools in one place:
Try playing around with the user controls. Note that redundant vertices are will be removed whenever they appear; new vertices can be added by clicking anywhere on the link. Double-clicking a vertex removes it. The disconnected handles are link anchors; when moved, they stay within the bounds of their respective end elements.
const linkView = link.findView(paper);
linkView.addTools(toolsView);
Remember, it is necessary to create a new tools view object for every link view; tools view objects are automatically reassigned to the last link view that uses them.
Interactionβ
You can easily toggle link tools using the 'link:mouseenter'
/'link:mouseleave'
Paper events:
paper.on('link:mouseenter', function(linkView) {
linkView.addTools(toolsView);
});
paper.on('link:mouseleave', function(linkView) {
linkView.removeTools();
});
More complex interaction scenarios might require showing, hiding or removing all tools at once. You can find relevant functions in the Paper class:
paper.showTools()
- shows tools on all link and element views.paper.hideTools()
- hides tools on all link and element views.paper.removeTools()
- removes tools from all link and element views.
These functions can also help to make anchor handles (which usually lie outside the path but inside an element) more accessible to users - by removing link tools only if the mouse pointer enters a blank area of the paper:
paper.on('link:mouseenter', function(linkView) {
linkView.addTools(toolsView);
});
paper.on('blank:mouseover', function() {
paper.removeTools();
});
Note that our example toggles visibility of link tools by using the addTools()
/removeTools()
functions, and not showTools()
/hideTools()
which we have seen in the element tools tutorial. This is necessary because the tools view in our tutorial includes the SourceArrowhead
and TargetArrowhead
tools, which may cause the link tools view to not be hidden as expected when the link is reconnected to a topic. Tools views without those two tools may use the showTools()
/hideTools()
approach illustrated in the element tools tutorial without issue.
Custom Buttonsβ
It is possible to create custom buttons to complement the pre-made Remove
button tool; JointJS exposes the linkTools.Button
class for you to extend. The markup of the new button can be sent as options.markup
, while the behavior of the button on pointerdown interaction is determined by the callback function provided in options.action
.
You can add the extended button to the linkTools
namespace and then just use that class in the code:
import { dia, linkTools } from '@joint/core';
linkTools.InfoButton = linkTools.Button.extend({
name: 'info-button',
options: {
markup: [{
tagName: 'circle',
selector: 'button',
attributes: {
'r': 7,
'fill': '#001DFF',
'cursor': 'pointer'
}
}, {
tagName: 'path',
selector: 'icon',
attributes: {
'd': 'M -2 4 2 4 M 0 3 0 0 M -2 -1 1 -1 M -1 -4 1 -4',
'fill': 'none',
'stroke': '#FFFFFF',
'stroke-width': 2,
'pointer-events': 'none'
}
}],
distance: 60,
offset: 0,
action: function(evt) {
alert('View id: ' + this.id + '\n' + 'Model id: ' + this.model.id);
}
}
});
const infoButton = new linkTools.InfoButton();
const toolsView = new dia.ToolsView({
tools: [infoButton]
});
const linkView = link.findView(paper);
linkView.addTools(toolsView);
A single-use custom button can also be created by direct reference to the Button
class, without making an entry in the linkTools
namespace:
import { dia, linkTools } from '@joint/core';
const infoButton = new linkTools.Button({
markup: [{
tagName: 'circle',
selector: 'button',
attributes: {
'r': 7,
'fill': '#001DFF',
'cursor': 'pointer'
}
}, {
tagName: 'path',
selector: 'icon',
attributes: {
'd': 'M -2 4 2 4 M 0 3 0 0 M -2 -1 1 -1 M -1 -4 1 -4',
'fill': 'none',
'stroke': '#FFFFFF',
'stroke-width': 2,
'pointer-events': 'none'
}
}],
distance: 60,
offset: 0,
action: function(evt) {
alert('View id: ' + this.id + '\n' + 'Model id: ' + this.model.id);
}
});
const toolsView = new dia.ToolsView({
tools: [infoButton]
});
const linkView = link.findView(paper);
linkView.addTools(toolsView);