TcxTrackBar Class

A simple track bar editor.

Declaration

TcxTrackBar = class(
    TcxCustomTrackBar
)

Remarks

A simple track bar editor (TcxTrackBar/TcxDBTrackBar) uses a thumb to specify a numeric value.

You can arrange a track bar editor horizontally or vertically, flip the scale direction, and customize the appearance of scale, thumb, tick marks, and other track bar elements.

In this topic…

• How to Use TcxTrackBar

• End-User Options

  • Track Click & Thumb Drag Operations
  • Supported Keystrokes
  • Mouse Wheel Support

• Main API Members

  • Appearance Settings
  • Content-Related APIs
  • Editor Settings and Repository Items
  • General-Purpose API Members

• Repository Item Class

• Related Compiled Demo

• Other Track Bar Editor Types

  • Unbound Editors
  • Data-Aware Editors

How to Use TcxTrackBar

At design time, you can add a TcxTrackBar using the Component Palette in your RAD Studio IDE. To create and use TcxTrackBar components in code, add the cxTrackBar unit to the uses clause of your project (in Delphi) or include the cxTrackBar header in the source code file (in C++Builder).

End-User Options

Track bar editors (TcxCustomTrackBar descendants) support multiple mouse/touch and keyboard-based user interaction options.

Track Click & Thumb Drag Operations

Users can drag the thumb to modify the edit value.

In addition, a click on the track bar before or after the thumb changes its position in increments specified by the Properties.PageSize property value. If the Properties.ThumbStep property is set to cxtsJump, a click on the track bar moves the thumb directly to the target position.

Supported Keystrokes

If the track bar editor has focus, the following keys increment or decrement the edit value (depending on the Properties.ReverseDirection property value):

Page Up | Page DownIncrement/decrement the edit value by Properties.PageSize.→ | ↑ | ↓ | ← | + | -Increment/decrement the edit value by Properties.LineSize. These keys correspond to change buttons.

Mouse Wheel Support

Users can rotate the mouse wheel to increment/decrement[1] the editor value when the following conditions are met:

• The track bar editor has focus
• The mouse pointer is within the editor client area
• The Properties.UseMouseWheel property is set to True ( default )

Main API Members

The list below outlines key members of the TcxTrackBar class. These members allow you to configure track bar editors.

Appearance Settings

Style | StyleDisabled | StyleFocused | StyleHot | StyleReadOnly

Allow you to define individual appearance settings for different track bar editor states.

Tip

To apply the same style settings to multiple editors, use a TcxEditStyleController component. If you need to apply the same style settings to all editors in your application, you can use a TcxDefaultEditStyleController component.

StylesProvides access to individual styles applied to the track bar editor in different states.TransparentSpecifies if the track bar editor is transparent in GDI render mode.

Content-Related APIs

EditValueSpecifies the edit value.PositionSpecifies the track thumb position.

Editor Settings and Repository Items

ActivePropertiesProvides access to the current track bar editor settings regardless of their source. This property set does not allow you to customize editor settings.PropertiesAllows you to customize track bar editor settings directly if the editor does not have an assigned repository item.RepositoryItemSpecifies a repository item as an external source of track bar editor settings. A repository item has priority over other editor settings.

General-Purpose API Members

AutoSizeSpecifies if the track bar editor automatically adjusts its size to fit all visible UI elements in full.EnabledSpecifies if the editor is enabled.CanModifyIdentifies if the editor is in read-only mode.ShowHintSpecifies if the standalone track bar editor can display hints. To enable hints for an in-place editor in a container control, set its OptionsBehavior.CellHints[2] property to True.Width | HeightAllow you to explicitly define editor dimensions.

Repository Item Class

You can create a TcxEditRepositoryTrackBar component in an edit repository to define an unbound track bar editor (TcxTrackBar), store track bar settings, and share them between multiple track bar editors.

Related Compiled Demo

To see the TcxTrackBar editor in action, run the Data Editors and Controls demo in the VCL Demo Center installed with compiled DevExpress VCL demos. Click Track Bar in the sidebar on the left to activate the corresponding demo.

Download: Compiled VCL Demos

Tip

You can find full source code for the installed compiled editor demo in the following folder:

_%PUBLIC%\Documents\DevExpress VCL Demos\MegaDemos\Product Demos\ExpressEditors_

Other Track Bar Editor Types

Unbound Editors

TdxRangeTrackBarAn unbound range track bar editor.TdxZoomTrackBarAn unbound zoom track bar editor similar to the zoom slider found in Microsoft Office.

Data-Aware Editors

TdxDBRangeTrackBarA data-aware range track bar editor.TdxDBZoomTrackBarA data-aware zoom track bar editor similar to the zoom slider found in Microsoft Office.

Inheritance

Show 13 items

TObject TPersistent TComponent TControl TWinControl TCustomControl TcxCustomControl TcxControl TcxContainer TcxCustomEditContainer TcxCustomEdit TcxCustomTrackBar TcxTrackBar

Footnotes

1. To flip the direction of mouse wheel rotation, you can set the Properties.ReverseMouseWheel property to True.

2. Set the following behavior properties to True or False to enable or disable in-place editor hints in corresponding container controls:

See Also

TcxDBTrackBar Class

TcxTrackBar Members

cxTrackBar Unit