Programming Microsoft Visual Basic .NET/Programming Microsoft Visual Basic .NET (Microsoft Press)(X08-78517)(2002).bin/setup/vbnet/17 controls/customcontroldemo/filetextbox.vb

Text File | 2002-03-19 | 10.2 KB | 294 lines

Imports System.ComponentModel

' a textbox control that lets you open the FileOpen dialog

'<ToolboxBitmap("E:\Program Files\Microsoft Visual Studio .NET\Common7\Graphics\icons\Computer\Disk08.ico")> _
Public Class FileTextBox
    Inherits System.Windows.Forms.UserControl

#Region " Windows Form Designer generated code "

    Public Sub New()
        MyBase.New()

        'This call is required by the Windows Form Designer.
        InitializeComponent()

        'Add any initialization after the InitializeComponent() call

    End Sub

    'UserControl overrides dispose to clean up the component list.
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub
    Friend WithEvents txtFilename As System.Windows.Forms.TextBox
    Friend WithEvents btnBrowse As System.Windows.Forms.Button
    Friend WithEvents OpenFileDialog1 As System.Windows.Forms.OpenFileDialog

    'Required by the Windows Form Designer
    Private components As System.ComponentModel.Container

    'NOTE: The following procedure is required by the Windows Form Designer
    'It can be modified using the Windows Form Designer.
    'Do not modify it using the code editor.
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.btnBrowse = New System.Windows.Forms.Button()
        Me.OpenFileDialog1 = New System.Windows.Forms.OpenFileDialog()
        Me.txtFilename = New System.Windows.Forms.TextBox()
        Me.SuspendLayout()
        '
        'btnBrowse
        '
        Me.btnBrowse.Location = New System.Drawing.Point(256, 8)
        Me.btnBrowse.Name = "btnBrowse"
        Me.btnBrowse.Size = New System.Drawing.Size(24, 24)
        Me.btnBrowse.TabIndex = 1
        Me.btnBrowse.Text = "..."
        '
        'OpenFileDialog1
        '
        Me.OpenFileDialog1.Filter = "All Files (*.*)|*.*"
        '
        'txtFilename
        '
        Me.txtFilename.Location = New System.Drawing.Point(8, 8)
        Me.txtFilename.Name = "txtFilename"
        Me.txtFilename.Size = New System.Drawing.Size(248, 20)
        Me.txtFilename.TabIndex = 0
        Me.txtFilename.Text = ""
        '
        'FileTextBox
        '
        Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.btnBrowse, Me.txtFilename})
        Me.Name = "FileTextBox"
        Me.Size = New System.Drawing.Size(296, 40)
        Me.ResumeLayout(False)

    End Sub

#End Region

    '----------------------------------------------------------------
    ' The Filename property
    ' (a wrapper on the txtFilename.Text property)
    '----------------------------------------------------------------

    <Description("The filename as it appears in the textbox")> _
    Property Filename() As String
        Get
            Return Me.txtFilename.Text
        End Get
        Set(ByVal Value As String)
            Me.txtFilename.Text = Value
        End Set
    End Property

    '----------------------------------------------------------------
    ' The Filter property
    ' (a wrapper on the OpenFileDialog property with same name)
    '----------------------------------------------------------------

    <Description("The list of file filters"), DefaultValue("All files (*.*)|*.*")> _
    Property Filter() As String
        Get
            Return OpenFileDialog1.Filter
        End Get
        Set(ByVal Value As String)
            OpenFileDialog1.Filter = Value
        End Set
    End Property

    '----------------------------------------------------------------
    ' The Filter property
    ' (a wrapper on the OpenFileDialog property with same name)
    '----------------------------------------------------------------

    Property FilterIndex() As Integer
        Get
            Return OpenFileDialog1.FilterIndex
        End Get
        Set(ByVal Value As Integer)
            OpenFileDialog1.FilterIndex = Value
        End Set
    End Property

    '----------------------------------------------------------------
    ' The ForeColor property
    ' (a wrapper on the TextBox property with same name)
    '----------------------------------------------------------------

    Shadows Property ForeColor() As Color
        Get
            Return txtFilename.ForeColor
        End Get
        Set(ByVal Value As Color)
            txtFilename.ForeColor = Value
        End Set
    End Property

    ' Resetxxx and ShouldSerializexxxx methods

    Shadows Sub ResetForeColor()
        Me.ForeColor = SystemColors.ControlText
    End Sub

    Function ShouldSerializeForeColor() As Boolean
        Return Not Me.ForeColor.Equals(SystemColors.ControlText)
    End Function

    '----------------------------------------------------------------
    ' The BackColor property
    ' (a wrapper on the TextBox property with same name)
    '----------------------------------------------------------------

    Shadows Property BackColor() As Color
        Get
            Return txtFilename.BackColor
        End Get
        Set(ByVal Value As Color)
            txtFilename.BackColor = Value
        End Set
    End Property

    ' Resetxxx and ShouldSerializexxxx methods

    Shadows Sub ResetBackColor()
        Me.BackColor = SystemColors.Window
    End Sub

    Function ShouldSerializeBackColor() As Boolean
        Return Not Me.BackColor.Equals(SystemColors.Window)
    End Function

    '----------------------------------------------------------------
    ' The ShowDialog method
    ' (a wrapper on the OpenFileDialog method with same name)
    '----------------------------------------------------------------

    Function ShowDialog() As DialogResult
        ' show the OpenFile dialog, return the result
        ShowDialog = OpenFileDialog1.ShowDialog
        ' If the result is ok, assign the filename to the TextBox
        If ShowDialog = DialogResult.OK Then
            txtFilename.Text = OpenFileDialog1.FileName
        End If
    End Function

    ' open the FileOpen dialog when the browse button is clicked

    Private Sub btnBrowse_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnBrowse.Click
        ShowDialog()
    End Sub

    ' Expose the TextChanged event to the outside, under another name
    Event FilenameChanged(ByVal sender As Object, ByVal e As System.EventArgs)

    Private Sub txtFilename_TextChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles txtFilename.TextChanged
        RaiseEvent FilenameChanged(Me, e)
    End Sub

    ' Expose the two OpenFileDialog events to the outside

    Event FileOk(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs)
    Event HelpRequest(ByVal sender As Object, ByVal e As System.EventArgs)

    Private Sub OpenFileDialog1_FileOk(ByVal sender As Object, ByVal e As System.ComponentModel.CancelEventArgs) Handles OpenFileDialog1.FileOk
        OnFileOk(e)
    End Sub

    Private Sub OpenFileDialog1_HelpRequest(ByVal sender As Object, ByVal e As System.EventArgs) Handles OpenFileDialog1.HelpRequest
        OnHelpRequest(e)
    End Sub

    Protected Overridable Sub OnFileOk(ByVal e As System.ComponentModel.CancelEventArgs)
        RaiseEvent FileOk(Me, e)
    End Sub

    Protected Overridable Sub OnHelpRequest(ByVal e As EventArgs)
        RaiseEvent HelpRequest(Me, e)
    End Sub


    Private Sub FileTextBox_Resize(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Resize
        RedrawControls()
    End Sub

    Protected Overrides Sub OnFontChanged(ByVal e As System.EventArgs)
        ' Let the base control update the TextBox control.
        MyBase.OnFontChanged(e)
        ' Now we can redraw controls if necessary.
        RedrawControls()
    End Sub

    ' correctly resize child controls

    Private Sub RedrawControls()
        ' This is the width of the control.
        Dim width As Integer = Me.ClientRectangle.Width
        ' This is the (desired) height of the control.
        Dim btnSide As Integer = txtFilename.Height

        ' Adjust the height of the UserControl if necessary.
        If Me.ClientRectangle.Height <> btnSide Then
            ' Resize the UserControl.
            Me.SetClientSizeCore(Me.ClientRectangle.Width, btnSide)
            ' the above statement fires a nested Resize event, so exit right now.
            Exit Sub
        End If

        ' Resize the constituent controls.
        txtFilename.SetBounds(0, 0, width - btnSide, btnSide)
        btnBrowse.SetBounds(width - btnSide, 0, btnSide, btnSide)
    End Sub

    '----------------------------------------------------------------
    ' Override properties in order to hide them in the Property window
    '----------------------------------------------------------------

    <Browsable(False)> _
    Shadows Property AutoScroll() As Boolean
        Get
            If Not Me.DesignMode Then
                Throw New NotImplementedException()
            End If
        End Get
        Set(ByVal Value As Boolean)
            If Not Me.DesignMode Then
                Throw New NotImplementedException()
            End If
        End Set
    End Property

    ' ensure that all controls point to the same context menu

    Overrides Property ContextMenu() As ContextMenu
        Get
            Return MyBase.ContextMenu
        End Get
        Set(ByVal Value As ContextMenu)
            MyBase.ContextMenu = Value
            ' Propagate the new value to constituent controls.
            Dim ctrl As Control
            For Each ctrl In Me.Controls
                ctrl.ContextMenu = Me.ContextMenu
            Next
        End Set
    End Property

    ' change the style of the button when the Enabled property changes

    Private Sub FileTextBox_EnabledChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.EnabledChanged
        If Me.Enabled Then
            btnBrowse.FlatStyle = FlatStyle.Standard
        Else
            btnBrowse.FlatStyle = FlatStyle.Flat
        End If
    End Sub
End Class