datatable_callback: Callback that adds shiny inputs for specific events
In DavidBarke/shinyExplorer: Explorer and Contextmenu for Shiny apps

The output of this function may be used as the callback argument to datatable. Event listeners for dblclick and contextmenu are added to the datatable. These event listeners set a shiny input, so that you can listen to these events on the R-side with observeEvent. See 'Details' for the properties of the added inputs.

1	datatable_callback(inputId)

inputId

Typically the outputId used for displaying the corresponding datatable.

The callback adds the following inputs: input$<inputId>_row_dblclicked and input$<inputId>_row_contextmenued, where <inputId> is replaced by the parameter inputId passed to this function. These inputs have the following properties:

<inputId>_row_dblclicked

`row`	The index of the dblclicked row.
`id`	The value of the first column of the dblclicked row. It is convenient to create unique ids for every row in the first column of a table passed to `datatable` and hiding this column via the `options` argument.
`data`	The data of the dblclicked row.
`rnd`	A random number.

<inputId>_row_contextmenued

`row`	The index of the dblclicked row.
`id`	The value of the first column of the dblclicked row. It is convenient to create unique ids for every row in the first column of a table passed to `datatable` and hiding this column via the `options` argument.
`data`	The data of the dblclicked row.
`mouse`	A list with elements named `x` and `y` holding the position of the mouse in px, when the datatable was contextmenued.
`rnd`	A random number.