LabelEditingEventArgs

A handled instance of LabelEditingEventArgs will not be passed to further event handlers or an IEditLabelHelper instance.

Setting a value to label, owner, or cancel implicitly also sets this to true.

Note that this property needs to be set before the function synchronously returns. This means that setting the value in an async function after the first await or in an asynchronous callback, it cannot not be seen by the emitter of the event and the sender will consider the event as not being handled.

// wrong:
mode.editLabelInputMode.addEventListener(
  'query-label-adding',
  async (evt) => {
    await something()
    evt.handled = true // will be set *after* all other event listeners have been invoked, only
  },
)

// correct:
mode.editLabelInputMode.addEventListener(
  'query-label-adding',
  async (evt) => {
    evt.handled = true // will be set immediately and 'mode' will see the change
    await something()
  },
)

This can be set to an existing label to edit a specific one, or set to null to add a new label instead (e.g. for ILabelOwners that have no label yet).

If this property is explicitly set to null, the properties style, preferredSize, layoutParameter, and tag are used for the newly-added label, just like with LabelEditingEventArgs.

Setting this property implicitly also sets handled to true.

Note that this property may be initialized to null by calling code. However, in order to trigger automatically adding a new label, you need to set the property value explicitly to null even in that case.

This property can be null if there is no owner known, e.g. if the event is raised for non-ILabelOwners. Otherwise, it is initially set to the item for which the event is raised.

Setting this property implicitly also sets handled to true.