Slider

A slider is a control with a handle which can be pulled back and forth to change the value.

On Windows, the track bar control is used.

Slider events are handled in the same way as a scrollbar.

Window Styles

This class supports the following styles:

• SL_HORIZONTAL: Displays the slider horizontally (this is the default).
• SL_VERTICAL: Displays the slider vertically.
• SL_AUTOTICKS: Displays tick marks. Windows only.
• SL_MIN_MAX_LABELS: Displays minimum, maximum labels (new since wxWidgets 2.9.1).
• SL_VALUE_LABEL: Displays value label (new since wxWidgets 2.9.1).
• SL_LABELS: Displays minimum, maximum and value labels (same as SL_VALUE_LABEL and SL_MIN_MAX_LABELS together).
• SL_LEFT: Displays ticks on the left and forces the slider to be vertical.
• SL_RIGHT: Displays ticks on the right and forces the slider to be vertical.
• SL_TOP: Displays ticks on the top.
• SL_BOTTOM: Displays ticks on the bottom (this is the default).
• SL_SELRANGE: Allows the user to select a range on the slider. Windows only.
• SL_INVERSE: Inverses the minimum and maximum endpoints on the slider. Not compatible with SL_SELRANGE.

Notice that

SL_LEFT , SL_TOP , SL_RIGHT and SL_BOTTOM specify the position of the slider ticks in MSW implementation and that the slider labels, if any, are positioned on the opposite side. So, to have a label on the left side of a vertical slider, ``SL_RIGHT`` must be used (or none of these styles at all should be specified as left and top are default positions for the vertical and horizontal sliders respectively).

Events Emitted by this Class

Handlers bound for the following event types will receive a ScrollEvent parameter.

• EVT_SCROLL: Process all scroll events.
• EVT_SCROLL_TOP: Process wxEVT_SCROLL_TOP scroll-to-top events (minimum position).
• EVT_SCROLL_BOTTOM: Process wxEVT_SCROLL_BOTTOM scroll-to-bottom events (maximum position).
• EVT_SCROLL_LINEUP: Process wxEVT_SCROLL_LINEUP line up events.
• EVT_SCROLL_LINEDOWN: Process wxEVT_SCROLL_LINEDOWN line down events.
• EVT_SCROLL_PAGEUP: Process wxEVT_SCROLL_PAGEUP page up events.
• EVT_SCROLL_PAGEDOWN: Process wxEVT_SCROLL_PAGEDOWN page down events.
• EVT_SCROLL_THUMBTRACK: Process wxEVT_SCROLL_THUMBTRACK thumbtrack events (frequent events sent as the user drags the thumbtrack).
• EVT_SCROLL_THUMBRELEASE: Process wxEVT_SCROLL_THUMBRELEASE thumb release events.
• EVT_SCROLL_CHANGED: Process wxEVT_SCROLL_CHANGED end of scrolling events (MSW only).
• EVT_COMMAND_SCROLL: Process all scroll events.
• EVT_COMMAND_SCROLL_TOP: Process wxEVT_SCROLL_TOP scroll-to-top events (minimum position).
• EVT_COMMAND_SCROLL_BOTTOM: Process wxEVT_SCROLL_BOTTOM scroll-to-bottom events (maximum position).
• EVT_COMMAND_SCROLL_LINEUP: Process wxEVT_SCROLL_LINEUP line up events.
• EVT_COMMAND_SCROLL_LINEDOWN: Process wxEVT_SCROLL_LINEDOWN line down events.
• EVT_COMMAND_SCROLL_PAGEUP: Process wxEVT_SCROLL_PAGEUP page up events.
• EVT_COMMAND_SCROLL_PAGEDOWN: Process wxEVT_SCROLL_PAGEDOWN page down events.
• EVT_COMMAND_SCROLL_THUMBTRACK: Process wxEVT_SCROLL_THUMBTRACK thumbtrack events (frequent events sent as the user drags the thumbtrack).
• EVT_COMMAND_SCROLL_THUMBRELEASE: Process wxEVT_SCROLL_THUMBRELEASE thumb release events.
• EVT_COMMAND_SCROLL_CHANGED: Process wxEVT_SCROLL_CHANGED end of scrolling events (MSW only).
• EVT_SLIDER: Process wxEVT_COMMAND_SLIDER_UPDATED which is generated after any change of Slider position in addition to one of the events above.

The difference between EVT_SCROLL_THUMBRELEASE and EVT_SCROLL_CHANGED

The EVT_SCROLL_THUMBRELEASE event is only emitted when actually dragging the thumb using the mouse and releasing it (This EVT_SCROLL_THUMBRELEASE event is also followed by an EVT_SCROLL_CHANGED event). The EVT_SCROLL_CHANGED event also occurs when using the keyboard to change the thumb position, and when clicking next to the thumb (In all these cases the EVT_SCROLL_THUMBRELEASE event does not happen). In short, the EVT_SCROLL_CHANGED event is triggered when scrolling/ moving has finished independently of the way it had started. Please see the widgets sample (“Slider” page) to see the difference between EVT_SCROLL_THUMBRELEASE and EVT_SCROLL_CHANGED in action.

See also

Events and Event Handling, ScrollBar

Inheritance Diagram

Inheritance diagram for class Slider

Control Appearance

wxMSW

wxMAC

wxGTK

Methods Summary

__init__	Default constructor.
ClearSel	Clears the selection, for a slider with the ``SL_SELRANGE`` style.
ClearTicks	Clears the ticks.
Create	Used for two-step slider construction.
GetLineSize	Returns the line size.
GetMax	Gets the maximum slider value.
GetMin	Gets the minimum slider value.
GetPageSize	Returns the page size.
GetRange
GetSelEnd	Returns the selection end point.
GetSelStart	Returns the selection start point.
GetThumbLength	Returns the thumb length.
GetTickFreq	Returns the tick frequency.
GetValue	Gets the current slider value.
SetLineSize	Sets the line size for the slider.
SetPageSize	Sets the page size for the slider.
SetRange	Sets the minimum and maximum slider values.
SetSelection	Sets the selection.
SetThumbLength	Sets the slider thumb length.
SetTick	Sets a tick position.
SetTickFreq	Sets the tick mark frequency and position.
SetValue	Sets the slider position.

Properties Summary

LineSize	See GetLineSize and SetLineSize
Max	See GetMax
Min	See GetMin
PageSize	See GetPageSize and SetPageSize
Range	See GetRange
SelEnd	See GetSelEnd
SelStart	See GetSelStart
ThumbLength	See GetThumbLength and SetThumbLength
TickFreq	See GetTickFreq and SetTickFreq
Value	See GetValue and SetValue

Class API

---

class Slider(Control)

A slider is a control with a handle which can be pulled back and forth to change the value.

Possible constructors:

Slider()

Slider(parent, id=ID_ANY, value=0, minValue=0, maxValue=100,
       pos=DefaultPosition, size=DefaultSize, style=SL_HORIZONTAL,
       validator=DefaultValidator, name=SliderNameStr)

Methods

---

__init__(self, *args, **kw)

Overloaded Implementations:

---

__init__ (self)

Default constructor.

---

__init__ (self, parent, id=ID_ANY, value=0, minValue=0, maxValue=100, pos=DefaultPosition, size=DefaultSize, style=SL_HORIZONTAL, validator=DefaultValidator, name=SliderNameStr)

Constructor, creating and showing a slider.

Parameters:

• parent (Window) – Parent window. Must not be None.
• id (int) – Window identifier. The value ID_ANY indicates a default value.
• value (int) – Initial position for the slider.
• minValue (int) – Minimum slider position.
• maxValue (int) – Maximum slider position.
• pos (Point) – Window position. If DefaultPosition is specified then a default position is chosen.
• size (Size) – Window size. If DefaultSize is specified then a default size is chosen.
• style (long) – Window style. See Slider.
• validator (Validator) – Window validator.
• name (string) – Window name.

See also

Create , Validator

---

---

ClearSel(self)

Clears the selection, for a slider with the ``SL_SELRANGE`` style.

Availability

Only available for MSW.

---

ClearTicks(self)

Clears the ticks.

Availability

Only available for MSW.

---

Create(self, parent, id=ID_ANY, value=0, minValue=0, maxValue=100, point=DefaultPosition, size=DefaultSize, style=SL_HORIZONTAL, validator=DefaultValidator, name=SliderNameStr)

Used for two-step slider construction.

See Slider for further details.

Parameters:

• parent (Window) –
• id (int) –
• value (int) –
• minValue (int) –
• maxValue (int) –
• point (Point) –
• size (Size) –
• style (long) –
• validator (Validator) –
• name (string) –

Return type:

bool

---

GetLineSize(self)

Returns the line size.

Return type:int

See also

SetLineSize

---

GetMax(self)

Gets the maximum slider value.

Return type:int

See also

GetMin , SetRange

---

GetMin(self)

Gets the minimum slider value.

Return type:int

See also

GetMin , SetRange

---

GetPageSize(self)

Returns the page size.

Return type:int

See also

SetPageSize

---

GetRange(self)

---

GetSelEnd(self)

Returns the selection end point.

Return type:int

Availability

Only available for MSW.

See also

GetSelStart , SetSelection

---

GetSelStart(self)

Returns the selection start point.

Return type:int

Availability

Only available for MSW.

See also

GetSelEnd , SetSelection

---

GetThumbLength(self)

Returns the thumb length.

Return type:int

Availability

Only available for MSW.

See also

SetThumbLength

---

GetTickFreq(self)

Returns the tick frequency.

Return type:int

Availability

Only available for MSW.

See also

SetTickFreq

---

GetValue(self)

Gets the current slider value.

Return type:int

See also

GetMin , GetMax , SetValue

---

SetLineSize(self, lineSize)

Sets the line size for the slider.

Parameters:lineSize (int) – The number of steps the slider moves when the user moves it up or down a line.

See also

GetLineSize

---

SetPageSize(self, pageSize)

Sets the page size for the slider.

Parameters:pageSize (int) – The number of steps the slider moves when the user pages up or down.

See also

GetPageSize

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SetRange(self, minValue, maxValue)

Sets the minimum and maximum slider values.

Parameters:

• minValue (int) –
• maxValue (int) –

See also

GetMin , GetMax

---

SetSelection(self, startPos, endPos)

Sets the selection.

Parameters:

• startPos (int) – The selection start position.
• endPos (int) – The selection end position.

MSW port.

Availability

Only available for MSW.

See also

GetSelStart , GetSelEnd

---

SetThumbLength(self, len)

Sets the slider thumb length.

Parameters:len (int) – The thumb length.

MSW port.

Availability

Only available for MSW.

See also

GetThumbLength

---

SetTick(self, tickPos)

Sets a tick position.

Parameters:tickPos (int) – The tick position.

MSW port.

Availability

Only available for MSW.

See also

SetTickFreq

---

SetTickFreq(self, n)

Sets the tick mark frequency and position.

Parameters:n (int) – Frequency. For example, if the frequency is set to two, a tick mark is displayed for every other increment in the slider’s range.

MSW port.

Availability

Only available for MSW.

See also

GetTickFreq

---

SetValue(self, value)

Sets the slider position.

Parameters:value (int) – The slider position.

Properties

---

LineSize

See GetLineSize and SetLineSize

---

Max

See GetMax

---

Min

See GetMin

---

PageSize

See GetPageSize and SetPageSize

---

Range

See GetRange

---

SelEnd

See GetSelEnd

---

SelStart

See GetSelStart

---

ThumbLength

See GetThumbLength and SetThumbLength

---

TickFreq

See GetTickFreq and SetTickFreq

---

Value

See GetValue and SetValue