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  "identifier" : "/documentation/AppKit/NSMatrix/mouseDown(with:)",
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# mouseDown(with:)

Responds to a mouse-down event.

```
func mouseDown(with event: NSEvent)
```

## Parameters

`event`

The mouse-down event.

## Discussion

A mouse-down event in a text cell initiates editing mode. A double click in any cell type except a text cell sends the double-click action of the receiver (if there is one) in addition to the single-click action.

Your code should never invoke this method, but you may override it to implement different mouse tracking than [`NSMatrix`](/documentation/AppKit/NSMatrix) does. The response of the receiver depends on its selection mode, as explained in the class description.

## See Also

[`-  sendAction`](/documentation/AppKit/NSMatrix/sendAction())

If the selected cell has both an action and a target, sends its action to its target.

[`-  sendDoubleAction`](/documentation/AppKit/NSMatrix/sendDoubleAction())

Sends the double-click action message to the target of the receiver.


---

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