SendMessage 指定のウィンドウにメッセージを送る

'================================================================
'= コンボボックスのドロップダウンリスト座標
'=    (CB_GETDROPPEDCONTROLRECT.bas)
'================================================================
#include "Windows.bi"

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

' ウィンドウにメッセージを送信
Declare Function Api_SendMessage& Lib "user32" Alias "SendMessageA" (ByVal hWnd&, ByVal wMsg&, ByVal wParam&, lParam As Any)

#define CB_GETDROPPEDCONTROLRECT &H152  'コンボボックスのドロップダウンリストボックスの長方形を取得する
#define CB_SHOWDROPDOWN &H14F           'コンボボックスのリストボックスの表示または非表示を切り替える

Var Shared Combo1 As Object
Var Shared Text1 As Object
Var Shared Button1 As Object

Combo1.Attach GetDlgItem("Combo1") : Combo1.SetFontSize 12
Text1.Attach GetDlgItem("Text1") : Text1.SetFontSize 12
Button1.Attach GetDlgItem("Button1") : Button1.SetFontSize 12

'================================================================
'=
'================================================================
Declare Sub MainForm_Start edecl ()
Sub MainForm_Start()
    Var mm(11) As String
    Var Ret As Long

    For i = 0 To 11
        Read mm(i)
        Combo1.AddString mm(i)
    Next

    'コンボボックスドロップダウン表示
    SetMousePointer 0
    Ret = Api_SendMessage(Combo1.GethWnd, CB_SHOWDROPDOWN, 1, ByVal 0)

    Data "January ", "February", "March", "April", "May", "June"
    Data "July", "August", "September", "October", "November", "December"
End Sub

'================================================================
'=
'================================================================
Declare Sub Button1_on edecl ()
Sub Button1_on()
    Var rct As RECT
    Var Ret As Long

    ' コンボボックスのドロップダウンリスト座標を取得
    Ret = Api_SendMessage(Combo1.GethWnd, CB_GETDROPPEDCONTROLRECT, CLng(0), rct)

    '結果を表示
    Text1.SetWindowText "(" & Trim$(Str$(rct.Left)) & "," & Trim$(Str$(rct.Top)) & ")-" & "(" & Trim$(Str$(rct.Right)) & "," & Trim$(Str$(rct.Bottom)) & ")"
End Sub

'================================================================
'=
'================================================================
While 1
    WaitEvent
Wend
Stop
End