# `wxMouseEvent`
[🔗](https://github.com/erlang/otp/blob/OTP-29.0.1/lib/wx/src/gen/wxMouseEvent.erl#L58)

This event class contains information about the events generated by the mouse: they
include mouse buttons press and release events and mouse move events.

All mouse events involving the buttons use `wxMOUSE_BTN_LEFT` for the left mouse button, `wxMOUSE_BTN_MIDDLE`
for the middle one and `wxMOUSE_BTN_RIGHT` for the right one. And if the system supports
more buttons, the `wxMOUSE_BTN_AUX1` and `wxMOUSE_BTN_AUX2` events can also be generated.
Note that not all mice have even a middle button so a portable application should avoid
relying on the events from it (but the right button click can be emulated using the left
mouse button with the control key under Mac platforms with a single button mouse).

For the `wxEVT_ENTER_WINDOW` and `wxEVT_LEAVE_WINDOW` events purposes, the mouse is
considered to be inside the window if it is in the window client area and not inside one
of its children. In other words, the parent window receives `wxEVT_LEAVE_WINDOW` event not
only when the mouse leaves the window entirely but also when it enters one of its children.

The position associated with a mouse event is expressed in the window coordinates of the
window which generated the event, you can use `wxWindow:clientToScreen/3` to convert it to screen coordinates and
possibly call `wxWindow:screenToClient/2` next to convert it to window coordinates of another window.

Note: Note the difference between methods like `leftDown/1` and the inherited `leftIsDown/1`: the former returns
true when the event corresponds to the left mouse button click while the latter returns
true if the left mouse button is currently being pressed. For example, when the user is
dragging the mouse you can use `leftIsDown/1` to test whether the left mouse button is (still)
depressed. Also, by convention, if `leftDown/1` returns true, `leftIsDown/1` will also return true in wxWidgets
whatever the underlying GUI behaviour is (which is platform-dependent). The same applies,
of course, to other mouse buttons as well.

See: `m:wxKeyEvent`

This class is derived, and can use functions, from:

* `m:wxEvent`

wxWidgets docs: [wxMouseEvent](https://docs.wxwidgets.org/3.2/classwx_mouse_event.html)

## Events

Use `wxEvtHandler:connect/3` with `wxMouseEventType` to subscribe to events of this type.

# `wxMouse`

```erlang
-type wxMouse() ::
          #wxMouse{type :: wxMouseEvent:wxMouseEventType(),
                   x :: integer(),
                   y :: integer(),
                   leftDown :: boolean(),
                   middleDown :: boolean(),
                   rightDown :: boolean(),
                   controlDown :: boolean(),
                   shiftDown :: boolean(),
                   altDown :: boolean(),
                   metaDown :: boolean(),
                   wheelRotation :: integer(),
                   wheelDelta :: integer(),
                   linesPerAction :: integer()}.
```

# `wxMouseEvent`

```erlang
-type wxMouseEvent() :: wx:wx_object().
```

# `wxMouseEventType`

```erlang
-type wxMouseEventType() ::
          left_down | left_up | middle_down | middle_up | right_down | right_up | motion |
          enter_window | leave_window | left_dclick | middle_dclick | right_dclick | mousewheel |
          aux1_down | aux1_up | aux1_dclick | aux2_down | aux2_up | aux2_dclick.
```

# `altDown`

```erlang
-spec altDown(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the Alt key is pressed.

Notice that `wxKeyEvent:getModifiers/1` should usually be used instead of this one.

# `aux1DClick`

```erlang
-spec aux1DClick(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the event was a first extra button double click.

# `aux1Down`

```erlang
-spec aux1Down(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the first extra button mouse button changed to down.

# `aux1Up`

```erlang
-spec aux1Up(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the first extra button mouse button changed to up.

# `aux2DClick`

```erlang
-spec aux2DClick(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the event was a second extra button double click.

# `aux2Down`

```erlang
-spec aux2Down(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the second extra button mouse button changed to down.

# `aux2Up`

```erlang
-spec aux2Up(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the second extra button mouse button changed to up.

# `button`

```erlang
-spec button(This, But) -> boolean() when This :: wxMouseEvent(), But :: wx:wx_enum().
```

Returns true if the event was generated by the specified button.

# `buttonDClick`

```erlang
-spec buttonDClick(This) -> boolean() when This :: wxMouseEvent().
```

# `buttonDClick`

```erlang
-spec buttonDClick(This, [Option]) -> boolean()
                      when This :: wxMouseEvent(), Option :: {but, wx:wx_enum()}.
```

If the argument is omitted, this returns true if the event was a mouse double click
event.

Otherwise the argument specifies which double click event was generated (see `button/2` for the
possible values).

# `buttonDown`

```erlang
-spec buttonDown(This) -> boolean() when This :: wxMouseEvent().
```

# `buttonDown`

```erlang
-spec buttonDown(This, [Option]) -> boolean() when This :: wxMouseEvent(), Option :: {but, wx:wx_enum()}.
```

If the argument is omitted, this returns true if the event was a mouse button down event.

Otherwise the argument specifies which button-down event was generated (see `button/2` for the
possible values).

# `buttonUp`

```erlang
-spec buttonUp(This) -> boolean() when This :: wxMouseEvent().
```

# `buttonUp`

```erlang
-spec buttonUp(This, [Option]) -> boolean() when This :: wxMouseEvent(), Option :: {but, wx:wx_enum()}.
```

If the argument is omitted, this returns true if the event was a mouse button up event.

Otherwise the argument specifies which button-up event was generated (see `button/2` for the
possible values).

# `cmdDown`

```erlang
-spec cmdDown(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the key used for command accelerators is pressed.

Same as `controlDown/1`. Deprecated.

Notice that `wxKeyEvent:getModifiers/1` should usually be used instead of this one.

# `controlDown`

```erlang
-spec controlDown(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the Control key or Apple/Command key under macOS is pressed.

This function doesn't distinguish between right and left control keys.

Notice that `wxKeyEvent:getModifiers/1` should usually be used instead of this one.

# `dragging`

```erlang
-spec dragging(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if this was a dragging event (motion while a button is depressed).

See: `moving/1`

# `entering`

```erlang
-spec entering(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the mouse was entering the window.

See: `leaving/1`

# `getButton`

```erlang
-spec getButton(This) -> integer() when This :: wxMouseEvent().
```

Returns the mouse button which generated this event or `wxMOUSE\_BTN\_NONE` if no button
is involved (for mouse move, enter or leave event, for example).

Otherwise `wxMOUSE_BTN_LEFT` is returned for the left button down, up and double click
events, `wxMOUSE_BTN_MIDDLE` and `wxMOUSE_BTN_RIGHT` for the same events for the middle
and the right buttons respectively.

# `getLinesPerAction`

```erlang
-spec getLinesPerAction(This) -> integer() when This :: wxMouseEvent().
```

Returns the configured number of lines (or whatever) to be scrolled per wheel action.

Default value under most platforms is three.

# `getLogicalPosition`

```erlang
-spec getLogicalPosition(This, Dc) -> {X :: integer(), Y :: integer()}
                            when This :: wxMouseEvent(), Dc :: wxDC:wxDC().
```

Returns the logical mouse position in pixels (i.e. translated according to the
translation set for the DC, which usually indicates that the window has been scrolled).

# `getPosition`

```erlang
-spec getPosition(This) -> {X :: integer(), Y :: integer()} when This :: wxMouseEvent().
```

Returns the physical mouse position.

# `getWheelAxis`

```erlang
-spec getWheelAxis(This) -> wx:wx_enum() when This :: wxMouseEvent().
```

Gets the axis the wheel operation concerns.

Usually the mouse wheel is used to scroll vertically so `wxMOUSE_WHEEL_VERTICAL` is
returned but some mice (and most trackpads) also allow to use the wheel to scroll
horizontally in which case `wxMOUSE_WHEEL_HORIZONTAL` is returned.

Notice that before wxWidgets 2.9.4 this method returned `int`.

# `getWheelDelta`

```erlang
-spec getWheelDelta(This) -> integer() when This :: wxMouseEvent().
```

Get wheel delta, normally 120.

This is the threshold for action to be taken, and one such action (for example, scrolling
one increment) should occur for each delta.

# `getWheelRotation`

```erlang
-spec getWheelRotation(This) -> integer() when This :: wxMouseEvent().
```

Get wheel rotation, positive or negative indicates direction of rotation.

Current devices all send an event when rotation is at least +/-WheelDelta, but finer
resolution devices can be created in the future.

Because of this you shouldn't assume that one event is equal to 1 line, but you should be
able to either do partial line scrolling or wait until several events accumulate before
scrolling.

# `getX`

```erlang
-spec getX(This) -> integer() when This :: wxMouseEvent().
```

Returns X coordinate of the physical mouse event position.

# `getY`

```erlang
-spec getY(This) -> integer() when This :: wxMouseEvent().
```

Returns Y coordinate of the physical mouse event position.

# `isButton`

```erlang
-spec isButton(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the event was a mouse button event (not necessarily a button down event -
that may be tested using `buttonDown/2`).

# `isPageScroll`

```erlang
-spec isPageScroll(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the system has been setup to do page scrolling with the mouse wheel
instead of line scrolling.

# `leaving`

```erlang
-spec leaving(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the mouse was leaving the window.

See: `entering/1`

# `leftDClick`

```erlang
-spec leftDClick(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the event was a left double click.

# `leftDown`

```erlang
-spec leftDown(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the left mouse button changed to down.

# `leftIsDown`

```erlang
-spec leftIsDown(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the left mouse button is currently down.

# `leftUp`

```erlang
-spec leftUp(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the left mouse button changed to up.

# `metaDown`

```erlang
-spec metaDown(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the Meta key was down at the time of the event.

# `middleDClick`

```erlang
-spec middleDClick(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the event was a middle double click.

# `middleDown`

```erlang
-spec middleDown(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the middle mouse button changed to down.

# `middleIsDown`

```erlang
-spec middleIsDown(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the middle mouse button is currently down.

# `middleUp`

```erlang
-spec middleUp(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the middle mouse button changed to up.

# `moving`

```erlang
-spec moving(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if this was a motion event and no mouse buttons were pressed.

If any mouse button is held pressed, then this method returns false and `dragging/1` returns true.

# `rightDClick`

```erlang
-spec rightDClick(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the event was a right double click.

# `rightDown`

```erlang
-spec rightDown(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the right mouse button changed to down.

# `rightIsDown`

```erlang
-spec rightIsDown(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the right mouse button is currently down.

# `rightUp`

```erlang
-spec rightUp(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the right mouse button changed to up.

# `shiftDown`

```erlang
-spec shiftDown(This) -> boolean() when This :: wxMouseEvent().
```

Returns true if the Shift key is pressed.

This function doesn't distinguish between right and left shift keys.

Notice that `wxKeyEvent:getModifiers/1` should usually be used instead of this one.

---

*Consult [api-reference.md](api-reference.md) for complete listing*
