# Panel events

A panel can fire several events, according to the panel type.

![](http://4wsplatform.org/wp-content/uploads/2015/12/panelEvents-1024x519.jpg)

In case of a **grid** (or **pivot grid** ), these are the allowed events:

* row click
* row double click
* before the rendering of the grid
* before a cell editing
* before the deleting of a row
* before inserting data in grid/form
* before editing data in grid/form
* before data loading 

```
gridXXX.store.baseParams.streamExport = "Y"; 
// use this scriptet to force the grid data export in stream mode, 
// i.e. to generate the CSV content step by step, when exporting the grid content
// in this way, the memory consumption is limited and the export if faster
// IMPORTANT NOTE: do not use this hint if your grid is filled by a 
// javascript based business component where the grid content is generated 
// (i) starting from multiple seocndary queries 
// or 
// (ii) the whole result set is fetched


gridXXX.store.baseParams.bigQuery = "Y"; 
// use this additional property to export in a temporary BigQuery table the content of the BigQuery table
// read through a server-side js business component
// linked to a JS type object.
// Note: in case of a BigQuery type object, this parameter would not be needed


```

* before data saving on copy mode
* before data saving on insert mode
* before data saving on edit mode
* after a cell editing
* after the deleting of a row
* after data loading
* after data saving in insert mode
* after data saving in edit mode
* click on Enter button
* column model creation
* multiselection in grid
* column headers
* before import row (Javascript Server only)
* after import row (Javascript Server only)
* before export

```
return { // all these attributes are optional
  cols: [ 
   // list of columns to prompt in the Export Dialog window: 
   // each element represents a column to show in the Export Dialog window, in terms of: attribute name, title, width, exportable/not exportable (pre-set value)
   ["userCodeId","User Code Id",100,true],
   [...],
   ...
  ], 
  defaultExportFormat: "...", // export format to pre-set in the Export Dialog window; allowed values: "XLS", "CSV (;)", "CSV (,)" 
  enqueue: true|false // if set to true, the export task is enqueued, i.e. only one export for this grid will be allowed at a time
}
```

>

In case of a **detail form** , these are the allowed events:

* before the rendering of the detail form
* before data loading
* before data saving in insert mode
* before data saving in edit mode
* before the deleting of the content
* after data loading
* after data saving in insert mode
* after data saving in edit mode
* after the deleting of the content
* on button click (listen to any additional button added to the top toolbar)

In case of a **tree** , these are the allowed events:

* node click
* tree check selected
* tree expand node

In case of a **filter** , these are the allowed events:

* after loading data
* before render
* when pressing search button
* when pressing undo button

In case of a **detail form** , these are the allowed events:

* Before data load

For each event it is possible to link an action defined through the "Actions" menu item.


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