界面开发之Flat3DButton

自己是否想过重画控件，现在用强大的VB来实现吧。

下例就是简单的利用VB中的CommandButton改变成Flat3DButton风格。其实就是利用VB的SubClass去处理父窗口的WM_DRAWITEM消息。

1. 建立一个标准EXE工程，加入Command1和Command2，将Command1的Style属性设为Graphical。

2. 加入模块，取名SubClass_Flat3DButton，贴进代码：

Option Explicit

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'Copyright 2002 40Star, All Rights Reserved.
'
'E-Mail      ：40Star@163.com
'Distribution：你可以完全自由随便的使用这段代码，不管你用于任何目的
'              程序在于交流和学习
'              如有任何BUG请和我联系
'
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Private Declare Function GetParent Lib "user32" _
    (ByVal hWnd As Long) As Long

Private Declare Function GetWindowLong Lib "user32" Alias _
    "GetWindowLongA" (ByVal hWnd As Long, _
    ByVal nIndex As Long) As Long

Private Declare Function SetWindowLong Lib "user32" Alias _
        "SetWindowLongA" (ByVal hWnd As Long, ByVal nIndex _
        As Long, ByVal dwNewLong As Long) As Long
       
Private Declare Function CallWindowProc Lib "user32" Alias _
        "CallWindowProcA" (ByVal lpPrevWndFunc As Long, ByVal _
        hWnd As Long, ByVal Msg As Long, ByVal wParam As _
        Long, ByVal lParam As Long) As Long
       
Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" _
    (Destination As Any, Source As Any, ByVal Length As Long)
   
Const GWL_WNDPROC = (-4&)

Dim PrevWndProc&

Private Const WM_DESTROY = &H2
Private Const WM_DRAWITEM = &H2B

Private Type RECT
    Left As Long
    Top As Long
    Right As Long
    Bottom As Long
End Type

Private Type DRAWITEMSTRUCT
    CtlType As Long
    CtlID As Long
    itemID As Long
    itemAction As Long
    itemState As Long
    hwndItem As Long
    hdc As Long
    rcItem As RECT
    itemData As Long
End Type

' Owner draw constants
Private Const ODT_BUTTON = 4
' Owner draw actions
Private Const ODA_DRAWENTIRE = &H1
Private Const ODA_SELECT = &H2
Private Const ODA_FOCUS = &H4
' Owner draw state
Private Const ODS_SELECTED = &H1
Private Const ODS_GRAYED = &H2
Private Const ODS_DISABLED = &H4
Private Const ODS_CHECKED = &H8
Private Const ODS_FOCUS = &H10

Private Declare Function GetWindowText Lib "user32" Alias _
    "GetWindowTextA" (ByVal hWnd As Long, ByVal lpString As String, _
    ByVal cch As Long) As Long

'Various GDI painting-related functions
Private Declare Function SelectObject Lib "gdi32" (ByVal hdc As Long, ByVal hObject As Long) As Long

Private Declare Function CreateSolidBrush Lib "gdi32" (ByVal crColor As Long) As Long

Private Declare Function DeleteObject Lib "gdi32" (ByVal hObject As Long) As Long

Private Declare Function GetSysColor Lib "user32" (ByVal nIndex As Long) As Long
' Color Types
Const CTLCOLOR_MSGBOX = 0
Const CTLCOLOR_EDIT = 1
Const CTLCOLOR_LISTBOX = 2
Const CTLCOLOR_BTN = 3
Const CTLCOLOR_DLG = 4
Const CTLCOLOR_SCROLLBAR = 5
Const CTLCOLOR_STATIC = 6
Const CTLCOLOR_MAX = 8   '  three bits max

Const COLOR_SCROLLBAR = 0
Const COLOR_BACKGROUND = 1
Const COLOR_ACTIVECAPTION = 2
Const COLOR_INACTIVECAPTION = 3
Const COLOR_MENU = 4
Const COLOR_WINDOW = 5
Const COLOR_WINDOWFRAME = 6
Const COLOR_MENUTEXT = 7
Const COLOR_WINDOWTEXT = 8
Const COLOR_CAPTIONTEXT = 9
Const COLOR_ACTIVEBORDER = 10
Const COLOR_INACTIVEBORDER = 11
Const COLOR_APPWORKSPACE = 12
Const COLOR_HIGHLIGHT = 13
Const COLOR_HIGHLIGHTTEXT = 14
Const COLOR_BTNFACE = 15
Const COLOR_BTNSHADOW = 16
Const COLOR_GRAYTEXT = 17
Const COLOR_BTNTEXT = 18
Const COLOR_INACTIVECAPTIONTEXT = 19
Const COLOR_BTNHIGHLIGHT = 20

Private Declare Function FillRect Lib "user32" (ByVal hdc As Long, lpRect As RECT, ByVal hBrush As Long) As Long

Private Declare Function FrameRect Lib "user32" (ByVal hdc As Long, lpRect As RECT, ByVal hBrush As Long) As Long

Private Declare Function RoundRect Lib "gdi32" (ByVal hdc As Long, ByVal X1 As Long, ByVal Y1 As Long, ByVal X2 As Long, ByVal Y2 As Long, ByVal X3 As Long, ByVal Y3 As Long) As Long

'pen Api
Private Declare Function CreatePen Lib "gdi32" (ByVal nPenStyle As Long, ByVal nWidth As Long, ByVal crColor As Long) As Long
'  Pen Styles
Const PS_SOLID = 0
Const PS_DASH = 1                    '  -------
Const PS_DOT = 2                     '  .......
Const PS_DASHDOT = 3                 '  _._._._
Const PS_DASHDOTDOT = 4              '  _.._.._
Const PS_NULL = 5
Const PS_INSIDEFRAME = 6
Const PS_USERSTYLE = 7
Const PS_ALTERNATE = 8
Const PS_STYLE_MASK = &HF

Private Declare Function MoveToEx Lib "gdi32" (ByVal hdc As Long, ByVal x As Long, ByVal y As Long, lpPoint As POINTAPI) As Long

Private Declare Function LineTo Lib "gdi32" (ByVal hdc As Long, ByVal x As Long, ByVal y As Long) As Long

Private Type POINTAPI
        x As Long
        y As Long
End Type

Private Declare Function DrawText Lib "user32" Alias "DrawTextA" _
    (ByVal hdc As Long, ByVal lpStr As String, ByVal nCount As Long, _
    lpRect As RECT, ByVal wFormat As Long) As Long

Private Const DT_SINGLELINE = &H20
Private Const DT_CENTER = &H1
Private Const DT_VCENTER = &H4

Private Declare Function SetTextColor Lib "gdi32" (ByVal hdc As Long, _
    ByVal crColor As Long) As Long
   
Private Declare Function SetBkMode Lib "gdi32" (ByVal hdc As Long, _
    ByVal nBkMode As Long) As Long
   
Private Const TRANSPARENT = 1

Private Sub DrawButton(ByVal hWnd As Long, ByVal hdc As Long, _
rct As RECT, ByVal nState As Long)

   Dim P As POINTAPI
   Dim s As String
   Dim hbr As Long
   Dim hpen As Long
   
   hbr = CreateSolidBrush(GetSysColor(COLOR_BTNFACE))
   SelectObject hdc, hbr
   FillRect hdc, rct, hbr
   DeleteObject hbr
  
   '画文字时背景为透明状
   SetBkMode hdc, TRANSPARENT
   '得到Button的Caption
   s = String$(255, 0)
   GetWindowText hWnd, s, 255
   s = Left$(s, InStr(s, Chr$(0)) - 1)
   '根据Button的Enabled状态进行重画
   If (nState And ODS_DISABLED) = ODS_DISABLED Then
      '画内侧3D效果->亮色
      hpen = CreatePen(PS_SOLID, 1, GetSysColor(COLOR_BTNHIGHLIGHT))
      SelectObject hdc, hpen
      MoveToEx hdc, rct.Left, rct.Top, P
      LineTo hdc, rct.Right, rct.Top
      MoveToEx hdc, rct.Left, rct.Top, P
      LineTo hdc, rct.Left, rct.Bottom
      DeleteObject hpen
      '画内侧3D效果->暗色
      hpen = CreatePen(PS_SOLID, 1, GetSysColor(COLOR_BTNSHADOW))
      SelectObject hdc, hpen
      MoveToEx hdc, rct.Left, rct.Bottom - 1, P
      LineTo hdc, rct.Right, rct.Bottom - 1
      MoveToEx hdc, rct.Right - 1, rct.Top, P
      LineTo hdc, rct.Right - 1, rct.Bottom
      DeleteObject hpen
      '画阴影文字
      rct.Left = rct.Left + 1
      rct.Right = rct.Right + 1
      rct.Bottom = rct.Bottom + 1
      rct.Top = rct.Top + 1
      SetTextColor hdc, GetSysColor(COLOR_BTNHIGHLIGHT)
      DrawText hdc, s, Len(s), rct, DT_CENTER Or DT_SINGLELINE Or DT_VCENTER
      rct.Left = rct.Left - 1
      rct.Right = rct.Right - 1
      rct.Bottom = rct.Bottom - 1
      rct.Top = rct.Top - 1
      SetTextColor hdc, GetSysColor(COLOR_GRAYTEXT)
      DrawText hdc, s, Len(s), rct, DT_CENTER Or DT_SINGLELINE Or DT_VCENTER
      Exit Sub
   End If
   '按下Button时重画
   If (nState And ODS_SELECTED) = ODS_SELECTED Then
      '画外围黑框
      hbr = CreateSolidBrush(GetSysColor(COLOR_BTNTEXT))
      SelectObject hdc, hbr
      FrameRect hdc, rct, hbr
      DeleteObject hbr
      hbr = CreateSolidBrush(GetSysColor(COLOR_BTNSHADOW))
      SelectObject hdc, hbr
      rct.Left = rct.Left + 1
      rct.Right = rct.Right - 1
      rct.Bottom = rct.Bottom - 1
      rct.Top = rct.Top + 1
      FrameRect hdc, rct, hbr
      DeleteObject hbr
     
      rct.Left = rct.Left + 1
      rct.Right = rct.Right + 1
      rct.Bottom = rct.Bottom + 1
      rct.Top = rct.Top + 1
      SetTextColor hdc, GetSysColor(COLOR_BTNTEXT)
      DrawText hdc, s, Len(s), rct, DT_CENTER Or DT_SINGLELINE Or DT_VCENTER
      Exit Sub
   End If
   'Button得到焦点时重画
   If (nState And ODS_FOCUS) = ODS_FOCUS Then
      '画外围黑框
      hbr = CreateSolidBrush(GetSysColor(COLOR_BTNTEXT))
      SelectObject hdc, hbr
      FrameRect hdc, rct, hbr
      DeleteObject hbr
      '画内侧3D效果->亮色
      hpen = CreatePen(PS_SOLID, 1, GetSysColor(COLOR_BTNHIGHLIGHT))
      SelectObject hdc, hpen
      MoveToEx hdc, rct.Left + 1, rct.Top + 1, P
      LineTo hdc, rct.Right - 1, rct.Top + 1
      MoveToEx hdc, rct.Left + 1, rct.Top + 1, P
      LineTo hdc, rct.Left + 1, rct.Bottom - 1
      DeleteObject hpen
      '画内侧3D效果->暗色
      hpen = CreatePen(PS_SOLID, 1, GetSysColor(COLOR_BTNSHADOW))
      SelectObject hdc, hpen
      MoveToEx hdc, rct.Left + 1, rct.Bottom - 2, P
      LineTo hdc, rct.Right - 1, rct.Bottom - 2
      MoveToEx hdc, rct.Right - 2, rct.Top + 1, P
      LineTo hdc, rct.Right - 2, rct.Bottom - 1
      DeleteObject hpen
     
      SetTextColor hdc, GetSysColor(COLOR_BTNTEXT)
      DrawText hdc, s, Len(s), rct, DT_CENTER Or DT_SINGLELINE Or DT_VCENTER
   Else
      '画内侧3D效果->亮色
      hpen = CreatePen(PS_SOLID, 1, GetSysColor(COLOR_BTNHIGHLIGHT))
      SelectObject hdc, hpen
      MoveToEx hdc, rct.Left, rct.Top, P
      LineTo hdc, rct.Right, rct.Top
      MoveToEx hdc, rct.Left, rct.Top, P
      LineTo hdc, rct.Left, rct.Bottom
      DeleteObject hpen
      '画内侧3D效果->暗色
      hpen = CreatePen(PS_SOLID, 1, GetSysColor(COLOR_BTNSHADOW))
      SelectObject hdc, hpen
      MoveToEx hdc, rct.Left, rct.Bottom - 1, P
      LineTo hdc, rct.Right, rct.Bottom - 1
      MoveToEx hdc, rct.Right - 1, rct.Top, P
      LineTo hdc, rct.Right - 1, rct.Bottom
      DeleteObject hpen
      '画阴影文字
      SetTextColor hdc, GetSysColor(COLOR_BTNTEXT)
      DrawText hdc, s, Len(s), rct, DT_CENTER Or DT_SINGLELINE Or DT_VCENTER
   End If
End Sub

Private Function SubWndProc(ByVal hWnd As Long, ByVal Msg As Long, _
                            ByVal wParam As Long, ByVal lParam As Long) _
                            As Long
   Dim di As DRAWITEMSTRUCT
   If Msg = WM_DESTROY Then Terminate (hWnd)
   '处理自画消息
   If Msg = WM_DRAWITEM Then
      CopyMemory di, ByVal lParam, Len(di)
      '判断是自画Button
      If di.CtlType = ODT_BUTTON Then
        
         DrawButton di.hwndItem, di.hdc, di.rcItem, di.itemState
         '不返回VB的默认Button绘制过程
         SubWndProc = 1
         Exit Function
      End If
     
   End If
   SubWndProc = CallWindowProc(PrevWndProc, hWnd, Msg, wParam, lParam)
End Function

Public Sub Init(hWnd As Long)
  PrevWndProc = SetWindowLong(hWnd, GWL_WNDPROC, AddressOf SubWndProc)
End Sub

Public Sub Terminate(hWnd As Long)
  Call SetWindowLong(hWnd, GWL_WNDPROC, PrevWndProc)
End Sub
' -- 模块结束 -- '

3. Form1中的代码：

Option Explicit

Private Sub Form_Load()
Call Init(Me.hWnd)
End Sub

Private Sub Form_Unload(Cancel As Integer)
Call Terminate(Me.hWnd)
End Sub

4. 结束语

怎么样，看到两个Button之间的不同了么

本程序在Win2000 + Vb6中调试通过