TExplorerBar

Source: source/classes/texplbar.prg

Inherits from: TControl

TExplorerBar is an Outlook-style vertical task panel with collapsible sections and gradient headers. Each section is represented by a TTaskPanel child object that can be expanded or collapsed by clicking its title bar. The panel supports vertical scrolling when content exceeds the visible area, making it suitable for navigation menus, task lists, and property groups.

Command Syntax

@ nRow, nCol EXPLORERBAR oBar OF oWnd SIZE nW, nH

Key DATA Members

DATA	Type	Description
`aPanels`	Array	Array of TTaskPanel objects added to the bar
`nTopColor`	Numeric	Top gradient color for the bar background (default RGB(122,161,230))
`nBottomColor`	Numeric	Bottom gradient color for the bar background (default RGB(99,117,214))
`oVScroll`	Object	Vertical scrollbar control for scrolling panel content
`nVPos`	Numeric	Current vertical scroll position
`nVirtualHeight`	Numeric	Total virtual height of all panels combined
`nVirtualTop`	Numeric	Current scroll offset from the top
`lSBVisible`	Logical	Scrollbar visibility flag
`aGradient`	Array	Custom gradient definition for panel headers
`bClrGrad`	Block	Code block returning custom gradient colors

TTaskPanel Class (Child of TExplorerBar)

DATA	Type	Description
`cTitle`	Character	Panel section title displayed in the header
`nTitleHeight`	Numeric	Height of the clickable title bar (default 25)
`nBodyHeight`	Numeric	Height of the body area when expanded (default 50)
`lCollapsed`	Logical	Whether the panel is currently collapsed
`aLinks`	Array	Array of TUrlLink controls added via AddLink()
`aGradient`	Array	Gradient colors for the title bar
`nRound`	Numeric	Corner rounding radius for the panel (default 6)
`bOnCollapse`	Block	Code block executed when the panel is collapsed/expanded

Methods

Method	Description
`New( nTop, nLeft, nWidth, nHeight, oWnd, nClrFore, nClrBack, oBrush, l2007, l2010, l2013, l2015 )`	Create a new TExplorerBar control
`Redefine( nId, oDlg )`	Redefine from dialog resource
`AddPanel( cName, cBmpName, nBodyHeight, nTitleH, nRound, aGrad, oFnt, nClrT, nClrP )`	Add a new TTaskPanel section. Returns the panel object.
`CloseAll( nExcept )`	Collapse all panels except the one at index nExcept (default 1)
`CheckScroll()`	Recalculate scrollbar range based on panel heights
`VScrollSetPos( nPos )`	Set the vertical scroll position and update panel positions
`VScrollSkip( nSkip )`	Scroll vertically by nSkip pixels

TTaskPanel Methods

Method	Description
`AddLink( cPrompt, bAction, cBitmap, oFnt, nClrT, nClrP, nClrO, cMsg, cTooltip )`	Add a clickable link to the panel body. Returns the TUrlLink object.
`LoadBitmaps( nType, cnBitmap )`	Load expand/collapse arrow bitmaps or a custom panel bitmap

Example: Explorer Bar with Two Panels

#include "FiveWin.ch"

function Main()

   local oWnd, oBar, oPanel

   DEFINE WINDOW oWnd TITLE "Explorer Bar Demo" SIZE 300, 500

   @ 0, 0 EXPLORERBAR oBar OF oWnd SIZE 300, 500

   // "Documents" panel with 2 links
   oPanel = oBar:AddPanel( "Documents",, 60, 25 )
   oPanel:AddLink( "Open Recent", { || MsgInfo( "Recent docs" ) }, "fileopen.bmp" )
   oPanel:AddLink( "Browse Folders", { || MsgInfo( "Browse" ) }, "folders.bmp" )

   // "Tools" panel with 2 links
   oPanel = oBar:AddPanel( "Tools",, 60, 25 )
   oPanel:AddLink( "Settings", { || MsgInfo( "Settings" ) }, "settings.bmp" )
   oPanel:AddLink( "Help", { || MsgInfo( "Help" ) }, "help.bmp" )

   ACTIVATE WINDOW oWnd CENTERED

return nil

Notes

Use the EXPLORERBAR command syntax to create the bar; panels are added programmatically with AddPanel().
Clicking a panel title bar toggles its collapsed state. The CloseAll() method collapses all panels except the specified one.
Each panel can display a bitmap in its header area (specified via cBmpName in AddPanel()).
Links inside panels are TUrlLink controls that support hover effects, tooltips, and custom colors.
The bar automatically manages vertical scrolling when panels extend beyond the visible area.
Visual styles (l2007, l2010, l2013, l2015) adjust the default appearance to match Windows version aesthetics.