Creating the Cover Designer Application

To create the Cover Designer application, you need to create the Cover Designer window, the Image Details window, the VisioEvents class, and the VisioMethods class.

Creating the Cover Designer Window

The CoverDesigner project uses the frmCoverDesigner class to define the Cover Designer application window. The application allows the end user to design the covers using the images in the picture boxes provided by the Cover Designer window. This window also allows the end user to save the designed covers, create a new cover, open an existing cover, and see the print preview of the cover.

Listing 6-2 shows the code for the frmCoverDesigner.vb file:

Listing 6-2: The frmCoverDesigner.vb File

 Imports System.IO Imports Microsoft.Office.Interop.Visio Imports System.Runtime.InteropServices Imports System.Data.SqlClient Public Class frmCoverDesigner     Inherits System.Windows.Forms.Form    'An array list to store the picture box controls in the gallery group box    Dim pictureboxlist As New ArrayList    Dim files() As String    'An object of the VisioEvents class that handles visio events    Dim objVisioEvents As VisioEvents    'The clickedImage object refers to the image that is clicked    Dim clickedImage As Shape    'A directory object to hold the path of current directory    Dim currentDirectory As Directory    'A string variable to hold the path of any folder    Dim currentPath As String    'An array list to hold the names of the opened drawings in the visio drawing control    Dim drawingControlList As New ArrayList    'The point on X-axis of visio drawing    Dim locationX As Double = 0.0    'The point on Y-axis of visio drawing    Dim locationY As Double = 0.0    'The shape returned when the user drops an image on the drawing control    Dim dropImage As Shape    Dim targetPage As Microsoft.Office.Interop.Visio.Page    'An object to act as the target stencil in which the images in the gallery are stored as shapes    Dim targetStencil As Document    Dim targetdocuments As Documents    'A variable that contains the total number of images on the drawing control    Dim totalImages As Integer    'A rectangle object to keep in track the area selected by the user on the drawing control to write some text.    Dim rect As New Rectangle    'A sqlconnection object to establish connection with CoverDesginer database    Dim sqlConnection As New SqlConnection    Private Sub frmCoverDesigner_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load       'Establish a connection with the CoverDesigner database to retrieve the image categories       Try          Try             'Read connectionstring from a text file, settings.txt, located in              '/bin folder of the application             Dim sr As New StreamReader("Settings.txt")             sqlConnection.ConnectionString = sr.ReadLine             sr.Close()             Catch ex As Exception             'If file settings.txt not found             sqlConnection.ConnectionString = "SERVER=localhost;UID=sa;PWD=sa;Initial Catalog=QueryTracker"          End Try          sqlConnection.Open()          Catch ex As Exception          MsgBox("Error in establishing connection", MsgBoxStyle.OKOnly, "CONNECTION ERROR")          Exit Sub       End Try       'Retrieving image categories from the database       Dim ds As New DataSet       Try          Dim sqlCommand As New SqlCommand("Select imageCategory from ImageCategory", sqlConnection)          Dim sqlda As New SqlDataAdapter(sqlCommand)          sqlda.Fill(ds)          Catch ex As Exception          MsgBox("Error in retrieving image categories from database", MsgBoxStyle.OKOnly, "Retrieval Error")          Exit Sub       End Try       'Adding the available image categories in the listCooseGallery list box       If Not ds.Tables.Count = 0 And Not ds.Tables(0).Rows.Count = 0 Then          Dim categoryCount As Integer          For categoryCount = 0 To ds.Tables(0).Rows.Count - 1             listChooseGallery.Items.Add(ds.Tables(0).Rows(categoryCount).Item(0))          Next       End If       'A variable to iterate through the picture box controls in the gallery group box       Dim pictureboxcount As Integer       'Adding the picture box controls in an array list collection       Dim i As Integer       For pictureboxcount = 0 To Gallery.Controls.Count - 1          If TypeOf Gallery.Controls(pictureboxcount) Is PictureBox Then             pictureboxlist.Add(Gallery.Controls(pictureboxcount))          End If       Next       listChooseGallery.SelectedIndex = 0       listChooseGallery_Click(listChooseGallery, e)       initializeVisioEvents()    End Sub    Private Sub listChooseGallery_Click(ByVal sender As Object, ByVal e As _    System.EventArgs) Handles listChooseGallery.Click       'When the user clicks one of the options provided in the listChooseGallery,        'the picture boxes in the gallery group box gets populated with the corresponding images.       'Retrieving path of the images on the hard disk that belongs to the selected image category.       Dim ds As new DataSet       Try          Dim sqlcommand As New SqlCommand("select imagePath from ImageCategory where _          imageCategory='" & listChooseGallery.Text & "'", sqlConnection)          Dim sqlda As New SqlDataAdapter(sqlcommand)          sqlda.Fill(ds)          Catch ex As Exception          MsgBox("Unable to retrieve the path of the selected image category", MsgBoxStyle.OKOnly, "Retrieval Error")          Exit Sub       End Try       If Not ds.Tables(0).Rows.Count = 0 Then          'Get all the image files for the selected image category          Try             files = Directory.GetFiles(ds.Tables(0).Rows(0).Item(0))             Catch ex As Exception             MsgBox("Unable to retrieve images for the selected category", _             MsgBoxStyle.OKOnly, "Retrieval Error")          End Try          Else          Exit Sub       End If       Dim filescount As Integer       'A bitmap object to hold the reference to the images stored in the music instruments folder       Dim objImage As Bitmap       'A temporary picturebox object       Dim tempPictureBox As New PictureBox       'A counter variable to iterate through the picture box controls stored in picture box list       Dim cntPictureBox As Integer = 0       'Iterate through the files array       Try          For filescount = 0 To files.Length - 1             'This if block prevents the cached thumbnail image from being loaded into picture box             If Not files(filescount).Substring(files(filescount).LastIndexOf("\") + 1).Equals("Thumbs.db") Then                'tempPictureBox holds the reference to the actual picturebox control in the pictureboxlist                tempPictureBox = pictureboxlist(cntPictureBox)                tempPictureBox.SizeMode = PictureBoxSizeMode.StretchImage                'Creating a new bitmap image                objImage = New Bitmap(files(filescount))                tempPictureBox.Image = CType(objImage, Image)                tempPictureBox.Text = files(filescount)                cntPictureBox += 1             End If          Next          Catch ex As Exception          MsgBox("Unable to load images", MsgBoxStyle.OKOnly, "Cannot load images")       End Try    End Sub    Private Sub onPictureBoxDoubleClick(ByVal sender As Object, ByVal e As System.EventArgs) _    Handles PictureBox1.DoubleClick, PictureBox2.DoubleClick, PictureBox3.DoubleClick, _    PictureBox4.DoubleClick, PictureBox5.DoubleClick, PictureBox6.DoubleClick, _    PictureBox7.DoubleClick, PictureBox8.DoubleClick, PictureBox9.DoubleClick, _    PictureBox10.DoubleClick, PictureBox11.DoubleClick, PictureBox12.DoubleClick, _    PictureBox13.DoubleClick, PictureBox14.DoubleClick, PictureBox15.DoubleClick, _    PictureBox16.DoubleClick, PictureBox17.DoubleClick, PictureBox18.DoubleClick    targetdocuments = drawingControl.Window.Application.Documents       Dim ds As New DataSet       'Retrieving the path of the stencil corresponding to selected image category       Try          Dim sqlCommand As New SqlCommand("select stencilPath, stencilName from stencils where _          stencilId=(select stencilId from ImageCategory where imageCategory='" & _          listChooseGallery.Text & "')", sqlConnection)          Dim sqlda As New SqlDataAdapter(sqlCommand)          sqlda.Fill(ds)          Catch ex As Exception          MsgBox("unable to retrieve the path of the stencil corresponding to _          selected image category", MsgBoxStyle.OKOnly, "Retrieval Error")          Exit Sub       End Try       'Opening the stencil containing the images shown in the picture boxes.       'The stencil is opened in invisible mode        If Not ds.Tables(0).Rows.Count = 0 Then          targetStencil = targetdocuments.OpenEx(ds.Tables(0).Rows(0).Item(0) & "/" _          & ds.Tables(0).Rows(0).Item(1), VisOpenSaveArgs.visOpenHidden)          Else          Exit Sub       End If       'Extracting the file name from the file path stored in the PictureBox text property       Dim tempPictureBox As PictureBox = CType(sender, PictureBox)       Dim extractFileName As String = tempPictureBox.Text       extractFileName = extractFileName.Substring(extractFileName.LastIndexOf("\") + 1)       'Extracting the master shape from the musicinstruments.vss stencil       Dim masters As Masters = targetStencil.Masters       'An object to hold a master shape from a Visio stencil       Dim master As Master       Try          master = masters.Item(extractFileName)          Catch ex As Exception          MsgBox("Master shape not found", MsgBoxStyle.OKOnly, "Invalid Path")          targetStencil.Close()          Exit Sub       End Try       'Dropping the master shape on the drawing control       Try          targetPage = drawingControl.Window.Page          dropImage = targetPage.Drop(master, locationX, locationY)          targetStencil.Close()          Catch ex As Exception          MsgBox("Unable to drop the image on drawing control", MsgBoxStyle.OKOnly, "Unable to drop image")       End Try    End Sub    Private Sub menuFileNew_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _    Handles menuFileNew.Click       Dim visualFeedbackOn As Integer = 1       Dim visualFeedbackOff As Integer = 0       'A new visio drawing is opened       Dim result As DialogResult       Dim visioApplication As Microsoft.Office.Interop.Visio.Application       'Prompt the user to save changes in the current drawing before closing current drawing       result = VisioMethods.SaveDrawing(drawingControl, True)       If result <> DialogResult.Cancel Then          visioApplication = drawingControl.Window.Application          drawingControl.Src = ""          Else          Exit Sub       End If       'Get the current state of the visual feedback.        'If visual feedback is on the end user will see changes in the drawing        'window as the code operates on the shapes.       Dim visualFeedbackStatus As Integer = visioApplication.ScreenUpdating       'Don't let the user see the visual feedback while the shapes are deleted.       If visualFeedbackStatus = visualFeedbackOn Then          visioApplication.ScreenUpdating = visualFeedbackOff       End If       'Delete all of the shapes from the Visio window.       Dim targetWindow As Microsoft.Office.Interop.Visio.Window       targetWindow = drawingControl.Window       Dim targetPage As Microsoft.Office.Interop.Visio.Page       targetPage = targetWindow.Page       If targetPage.Shapes.Count > 0 Then          targetWindow.SelectAll()          targetWindow.Selection.Delete()       End If       'Set the document saved flag since the drawing control is now displaying a blank document.       drawingControl.Document.Saved = True       'Restore the screen updating status.       If visualFeedbackStatus = visualFeedbackOn Then       visioApplication.ScreenUpdating = visualFeedbackOn       End If       'Re-initializing the totalImages count to zero       totalImages = 0       Label1.Text = ""    End Sub    Private Sub menuFileOpen_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _    Handles menuFileOpen.Click       'To open a drawing or a stencil       Dim openFileDialog As New OpenFileDialog       Dim targetDocuments As Documents       Dim fileName As String       Dim fileNameForCompare As String       Dim shapeNumber As Integer       Try          'Set up the open file dialog and let the user selects the file to open.          openFileDialog.Title = "Open visio document"          Dim currentDirectory As Directory          Dim currentPath As String          currentPath = currentDirectory.GetParent(currentDirectory.GetCurrentDirectory).ToString()          openFileDialog.InitialDirectory = currentPath          If openFileDialog.ShowDialog = DialogResult.OK Then             'The user has entered a file name and pressed OK. Get the file name              'from the dialog and open the file.             fileName = openFileDialog.FileName             fileNameForCompare = fileName.ToUpper(System.Globalization.CultureInfo.CurrentCulture)             'Checking if the user opens a stencil             If fileNameForCompare.IndexOf(".VSS") > 0 Or fileNameForCompare.IndexOf(".VSX") > 0 Then                targetDocuments = drawingControl.Window.Application.Documents()                'Open the stencil                targetDocuments.Open(fileName)                ElseIf fileNameForCompare.IndexOf(".VSD") > 0 Or _                fileNameForCompare.IndexOf(".VDX") > 0 Then                Dim result As DialogResult                'Only one document can be open. Prompt user to save changes                 'before closing the current document.                result = VisioMethods.SaveDrawing(drawingControl, True)                If result <> DialogResult.Cancel Then                   drawingControl.Src = ""                   'Open the new document                   drawingControl.Src = fileName                   drawingControl.Document.Saved = True                   'Set up the Visio drawing just opened                   setUpVisioDrawing()                   'Initialize Visio events for the opened drawing                   initializeVisioEvents()                   'Count the number of shapes in the opened drawing                   Dim targetPage As Page = drawingControl.Window.Page                   shapeNumber = targetPage.Shapes.Count                   'Resetting the totalImages counter                   totalImages = 0                   Dim countImages As Integer                   For countImages = 1 To shapeNumber                   onImageAdd()                   Next                End If             End If          End If          Catch ex As Exception          MsgBox("Unable to open the Visio drawing", MsgBoxStyle.OKOnly, "Retrieval Error")       End Try    End Sub    'The setUpVisioDrawing method initializes the Visio drawing that is displayed in the drawing control.    Public Sub setUpVisioDrawing()       Dim pageLeft As Double       Dim pageTop As Double       Dim pageWidth As Double       Dim pageHeight As Double       Dim distanceBetweenShapes As Double       Dim nextShapeXLocation As Double       Dim shapeNumber As Integer       Dim windowsCounter As Integer       Try          'Hide all built-in docked windows such as shape search, custom properties, etc.          For windowsCounter = drawingControl.Window.Windows.Count To windowsCounter > 0 Step -1             Dim visioWindow As Window             Dim windowType As Integer             visioWindow = drawingControl.Window.Windows.Item(windowsCounter)             windowType = visioWindow.Type             If windowType = VisWinTypes.visAnchorBarBuiltIn Then                Select Case visioWindow.ID                Case VisWinTypes.visWinIDCustProp                Case VisWinTypes.visWinIDDrawingExplorer                Case VisWinTypes.visWinIDMasterExplorer                Case VisWinTypes.visWinIDPanZoom                Case VisWinTypes.visWinIDShapeSearch                Case VisWinTypes.visWinIDSizePos                Case VisWinTypes.visWinIDStencilExplorer                visioWindow.Visible = False                End Select             End If          Next          'Use the Visio window to set the visible user interface parts of the window.          Dim targetWindow As Window          targetWindow = drawingControl.Window          targetWindow.ShowRulers = 0          targetWindow.ShowPageTabs = False          targetWindow.ShowScrollBars = 0          targetWindow.ShowGrid = 0          targetWindow.Zoom = 1.0          'Position the images relative to the page.          targetWindow.GetViewRect(pageLeft, pageTop, pageWidth, pageHeight)          'Start the visio events          initializeVisioEvents()          'The drawing control is displaying a newly opened document. Set the saved flag to true.          drawingControl.Document.Saved = True          Catch ex As Exception       End Try    End Sub    'initializeVisioEvents method initializes the VisioEvents event trapping on the document    Public Sub initializeVisioEvents()       Dim targetDocument As Document       Dim targetApplication As Microsoft.Office.Interop.Visio.Application       Try          objVisioEvents = New VisioEvents          targetApplication = drawingControl.Window.Application          targetDocument = drawingControl.Document          AddHandler objVisioEvents.OnImageAdd, AddressOf onImageAdd          AddHandler objVisioEvents.OnImageDelete, AddressOf onImageDelete          objVisioEvents.AddAdvise(targetApplication, targetDocument)          Catch ex As Exception       End Try    End Sub    Private Sub menuFileClose_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) _    Handles menuFileClose.Click       'Since only one document can exist, this operation is identical to the Menu-> New command       menuFileNew_Click(sender, e)    End Sub    Private Sub menuFilePrintPreview_Click(ByVal sender As System.Object, ByVal e As _    System.EventArgs) Handles menuFilePrintPreview.Click       'The System.Drawing.Printing objects are used provide print preview of the visio drawing to the user       Try          'Create a print document to handle the print preview functionality.           Dim printDocument As New System.Drawing.Printing.PrintDocument          Dim printPreviewDialog As New PrintPreviewDialog          'Add the local print page handler to print document          AddHandler printDocument.PrintPage, AddressOf onPrintDocument          printPreviewDialog.Document = printDocument          printPreviewDialog.ShowDialog()          Catch ex As Exception          MsgBox("unable to preview the visio drawing", MsgBoxStyle.OKOnly, "Invalid print status")       End Try    End Sub    'The onPrintDocument method handles the event that is raised when the user hits Print in the print dialog.    Private Sub onPrintDocument(ByVal sender As Object, ByVal e As _    System.Drawing.Printing.PrintPageEventArgs)       Dim metafileOriginX As Integer       Dim metafileOriginY As Integer       Dim pageWidth As Double       Dim pageHeight As Double       Dim tempShape As Shape       Dim targetPage As Page = drawingControl.Window.Page       'Draw a frame around the page so the bounding box of the picture is the size of the page.       pageWidth = targetPage.PageSheet.CellsSRC(VisSectionIndices.visSectionObject, _       VisRowIndices.visRowPage, VisCellIndices.visPageWidth.visPageWidth).ResultIU       pageHeight = targetPage.PageSheet.CellsSRC(VisSectionIndices.visSectionObject, _       VisRowIndices.visRowPage, VisCellIndices.visPageWidth.visPageHeight).ResultIU       'Creating the temporary shape which contains the visio page to be printed       tempShape = targetPage.DrawRectangle(0, 0, pageWidth, pageHeight)       tempShape.CellsSRC(VisSectionIndices.visSectionObject, VisRowIndices.visRowFill, _       VisCellIndices.visFillPattern).ResultIU = 0       'Make the line white so it's not visible on the page.       tempShape.CellsSRC(VisSectionIndices.visSectionObject, VisRowIndices.visRowLine, _       VisCellIndices.visLineColor).ResultIU = 1       'Create a metafile with the image of the page.       Try          Dim printInptr As New System.IntPtr(targetPage.Picture.Handle)          Dim printMetaFile As New System.Drawing.Imaging.Metafile(printInptr, False)          'Put the metafile image into the graphics of the print document.           'This causes the page image to be printed.          e.Graphics.DrawImage(printMetaFile, metafileOriginX, metafileOriginY)          Catch ex As Exception          MsgBox("Unable to preview the visio drawing", MsgBoxStyle.OKOnly, "Print Error")       End Try    End Sub    Private Sub frmCoverDesigner_Closing(ByVal sender As Object, ByVal e As _    System.ComponentModel.CancelEventArgs) Handles MyBase.Closing       'Before closing, prompt the user to save the document       Dim result As DialogResult       result = VisioMethods.SaveDrawing(drawingControl, True)       If result = DialogResult.Cancel Then          e.Cancel = True       End If    End Sub    Private Sub menuFileSave_Click(ByVal sender As System.Object, ByVal e As _    System.EventArgs) Handles menuFileSave.Click       Dim result As DialogResult       'Prompt user to save changes.       result = VisioMethods.SaveDrawing(drawingControl, False)    End Sub    Private Sub menuFileExit_Click(ByVal sender As System.Object, ByVal e As _    System.EventArgs) Handles menuFileExit.Click       Me.Close()    End Sub    'This procedure is called when an image is added on the drawing control    Private Sub onImageAdd()       totalImages += 1       Label1.Text = "Number of images on the Visio drawing : " & totalImages    End Sub    'This procedure is called when an image is deleted from the drawing control    Private Sub onImageDelete()       totalImages -= 1       If totalImages = 0 Then          Label1.Text = ""          Else          Label1.Text = "Number of images on the Visio drawing : " & totalImages       End If    End Sub    'This method handles the event that is raised when the user clicks on the drawing control.     'If the user clicked the right mouse button on any image, the shortcut menu     'is displayed at the click location.    Private Sub drawingControl_MouseUpEvent(ByVal sender As Object, ByVal e As _    AxMicrosoft.Office.Interop.VisOcx.EVisOcx_MouseUpEvent) Handles drawingControl.MouseUpEvent       'Check whether the event was raised because of a right mouse button click and not by zooming       '(control+shift+right mouse click) or by selecting images (control+right mouse click).       If e.button = VisKeyButtonFlags.visMouseRight And (e.keyButtonState And _       VisKeyButtonFlags.visKeyControl) = 0 Then          'Look for an image on the drawing page at the click location.          clickedImage = VisioMethods.GetClickedImage(drawingControl, e.x, e.y)          If Not clickedImage Is Nothing Then             'Cancel the default processing of this event since it will be handled in this method.             e.cancelDefault = True             'Show the shortcut menu at the click location.              'The coordinates need to be converted from the Visio drawing units to Windows pixel coordinates.             imageShortcutMenu.Show(drawingControl, VisioMethods.MapVisioToWindows(drawingControl, e.x, e.y))             shortcutMenu.PerformClick()          End If          ElseIf e.button = VisKeyButtonFlags.visMouseLeft Then          'To trap the coordinates to create the rectangle to allow the user to specify the text          If Not rect.X = CInt(e.x) And Not CInt(e.y) = rect.Y Then             Dim tp As Page = drawingControl.Window.Page             tp.DrawRectangle(rect.X, rect.Y, e.x, e.y)          End If       End If    End Sub    Private Sub drawingControl_VisibleChanged(ByVal sender As Object, ByVal e As _    System.EventArgs) Handles drawingControl.VisibleChanged       'If the drawing control is not on the list of initialized drawing controls,        'the control needs to be initialized.       If drawingControl.Visible And Not drawingControlList.Contains(drawingControl.Name) Then          'Set up the drawing, open the product stencil and start the visio events          setUpVisioDrawing()       End If       'Since all of the initialization tasks succeeded, save the drawing control        'in the list of initialized controls.       drawingControlList.Add(drawingControl.Name)    End Sub    Private Sub shortcutMenu_Click(ByVal sender As System.Object, ByVal e As _    System.EventArgs) Handles shortcutMenu.Click       Try          'Finding the image category for the clicked image on the visio drawing          Dim imageCategoryId As Integer          Dim targetDocuments As Documents = drawingControl.Window.Application.Documents          'Looking for the clicked image in the available stencils in the current visio drawing          Dim masters As Masters          Dim targetDocument As Document          Dim ds As New DataSet          Try             Dim sqlCommand As New SqlCommand("select * from stencils", sqlConnection)             Dim sqlda As New SqlDataAdapter(sqlCommand)             sqlda.Fill(ds)             Catch ex As Exception             Exit Sub          End Try          If Not ds.Tables(0).Rows.Count = 0 Then             Dim i As Integer             For i = 0 To ds.Tables(0).Rows.Count - 1             targetDocument = targetDocuments.OpenEx(ds.Tables(0).Rows(i).Item(2) & "/" _             & ds.Tables(0).Rows(i).Item(1), VisOpenSaveArgs.visOpenHidden)             masters = targetDocument.Masters             Try                If Not masters.Item(clickedImage.Name) Is Nothing Then                   Dim imageds As New DataSet                   Dim sqlcmd As New SqlCommand("select imageCategoryId from ImageCategory where _                   stencilId=" & ds.Tables(0).Rows(i).Item(0) & "", sqlConnection)                   Dim sqlda As New SqlDataAdapter(sqlcmd)                   sqlda.Fill(imageds)                   imageCategoryId = imageds.Tables(0).Rows(0).Item(0)                   targetDocument.Close()                                               Exit For                End If                Catch ex As Exception                targetDocument.Close()             End Try          Next       End If       'Create a metafile of the clicked image.       Dim imageInptr As New System.IntPtr(clickedImage.Picture.Handle)       Dim imageMetaFile As New System.Drawing.Imaging.Metafile(imageInptr, False)       'Calling the ImageDetails form       Dim objImageDetails As New ImageDetails(clickedImage.Name, imageCategoryId, imageMetaFile)       objImageDetails.ShowDialog()       Catch ex As Exception       MsgBox("Unable to display the image details", MsgBoxStyle.OKOnly, clickedImage.Name)    End Try    End Sub    Private Sub drawingControl_MouseDownEvent(ByVal sender As Object, ByVal e As _    AxMicrosoft.Office.Interop.VisOcx.EVisOcx_MouseDownEvent) _    Handles drawingControl.MouseDownEvent       'Trapping the coordinates on the visio control when user drags the        'mouse over the drawing control to make a rectangle to write some text       rect.X = CInt(e.x)       rect.Y = CInt(e.y)    End Sub End Class 

 

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In the above listing, the frmCoverDesigner class loads the image categories in the listChooseGallery list box. When the end user selects an image category from the list box, the picture boxes in the frmCoverDesigner form get loaded with images, which correspond to the selected category. When the end user clicks any picture box, the frmCoverDesigner class opens the Visio stencil (*.VST) according to the selected image category and searches for the clicked image. To view information about the image on the Visio drawing control, the end user right-clicks the image. The code creates an instance of the ImageDetails class to show the image information in the Image Details window. When a new Visio drawing starts, the ImageDetails class registers the events with the VisioEvents class.

Figure 6-3 shows the output of the Listing 6-2:

Figure 6-3: The Cover Designer Window

Creating the Image Details Window

The ImageDetails class defines the Image Details window. The ImageDetails class enables the end user to view the information about the selected image from the Visio drawing control.

Listing 6-3 shows the code for the frmImageDetails.vb that defines the ImageDetails class:

Listing 6-3: The frmImageDetails.vb File

 Imports System.Data.SqlClient Imports System.IO 'The ImageDetails class displays the details of an 'image retrieved by the Web service ImageInfoService onto a form. Public Class ImageDetails    Inherits System.Windows.Forms.Form    Dim imageFileName As String    Dim imageCategoryId As Integer    Dim imageMetafile As System.Drawing.Imaging.Metafile    Dim sqlConnection As New sqlConnection    Public Sub New(ByVal imageName As String, ByVal imageCatId As Integer, _    ByVal metafile As System.Drawing.Imaging.Metafile)       MyBase.New()       'This call is required by the Windows Form Designer.       InitializeComponent()       'Add any initialization after the InitializeComponent() call       imageFileName = imageName       imageCategoryId = imageCatId       imageMetafile = metafile       'Constructor requires the name of the image, image category, and metafile image as input       'This information is utilized by the ImageDetails to retrieve details of the specified image.    End Sub    Private Sub ImageDetails_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load       'Retrieving details for the specified image from the ImageInfoService Web service       Dim infoProvider As New localhost.ImageInfoService       Dim ds As DataSet = infoProvider.getImageInfo(imageCategoryId, imageFileName)       If Not ds Is Nothing And Not ds.Tables.Count = 0 And Not ds.Tables(0).Rows.Count = 0 Then          lblId.Text = lblId.Text & " " & ds.Tables(0).Rows(0).Item(0)          'Establish a connection with the CoverDesigner database to retrieve the Image Category          Try             Try                'Read connectionstring from a text file, settings.txt, located in                 '/bin folder of the application                Dim sr As New StreamReader("Settings.txt")                sqlConnection.ConnectionString = sr.ReadLine                sr.Close()                Catch ex As Exception                'If file settings.txt not found                sqlConnection.ConnectionString = _                "SERVER=localhost;UID=sa;PWD=sa;Initial Catalog=CoverDesigner"             End Try             sqlConnection.Open()             Catch ex As Exception             MsgBox("Error in establishing connection", MsgBoxStyle.OKOnly, "CONNECTION ERROR")             Exit Sub       End Try       Dim sqlCommand As New SqlCommand("select imageCategory from ImageCategory where _       imageCategoryId=" & imageCategoryId & "", sqlConnection)       Dim sqlda As New SqlDataAdapter(sqlCommand)       Dim imageds As New DataSet       sqlda.Fill(imageds)       lblCategory.Text = lblCategory.Text & " " & imageds.Tables(0).Rows(0).Item(0)       lblName.Text = lblName.Text & " " & ds.Tables(0).Rows(0).Item(2)       lblDescription.Text = lblDescription.Text & " " & ds.Tables(0).Rows(0).Item(3)       lblSource.Text = lblSource.Text & " " & ds.Tables(0).Rows(0).Item(4)       'Save the metafile in the picture box control that shows the clicked image       'Maintain metafile aspect and scale the metafile to fit in the Picture Box.       Dim metafileImage As System.Drawing.Image       Dim pictureBoxRect As System.Drawing.Rectangle       Dim metafileWidth As Double       Dim metafileHeight As Double       Dim horizontalScale As Double       Dim verticalScale As Double       Dim pictureWidth As Integer       Dim pictureHeight As Integer       PictureBox1.RectangleToClient(pictureBoxRect)       metafileWidth = imageMetafile.Width       metafileHeight = imageMetafile.Height       If metafileHeight > 0 And metafileWidth > 0 Then          verticalScale = pictureBoxRect.Height / metafileHeight          horizontalScale = pictureBoxRect.Width / metafileWidth          If verticalScale < horizontalScale Then             pictureWidth = CInt(metafileWidth * verticalScale)             pictureHeight = CInt(metafileHeight * verticalScale)             Else             pictureWidth = CInt(metafileWidth * horizontalScale)             pictureHeight = CInt(metafileHeight * horizontalScale)          End If          metafileImage = imageMetafile.GetThumbnailImage(pictureWidth, pictureHeight, Nothing, IntPtr.Zero)          PictureBox1.Image = metafileImage       End If    End If    End Sub End Class 

 

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In the above listing, the ImageDetails class accepts the image id, image category, and the meta file that represents the selected image, in the constructor of the ImageDetails class. Then, the ImageDetails class calls the getImageInfo function provided by the ImageInfoService Web service to display the image information on the frmImageDetails form.

Figure 6-4 shows the output of Listing 6-3:

Figure 6-4: The Image Details Window

Creating the VisioEvents Class

The VisioEvents.vb file defines the VisioEvents class that handles events from the Visio drawing tool. The VisioEvents class provides methods that trap the generated events when the end user designs the cover using the Visio drawing control.

Listing 6-4 shows the code for the VisioEvents.vb that defines the VisioEvents class:

Listing 6-4: The VisioEvents.vb File

 Imports System.Diagnostics Imports Microsoft.Office.Interop.Visio Public Class VisioEvents    Implements Microsoft.Office.Interop.Visio.IVisEventProc    'VisioEventHandler is an event delegate used for raising events for the     'Visio objects in the frmCoverDesigner class    Public Delegate Sub VisioEventHandler()    'A Visio application object    Dim visioApplication As Microsoft.Office.Interop.Visio.Application    'A Visio document object    Dim visioDocument As Document    'OnImageAdd event is raised when an image is added to the Visio drawing    Public Event OnImageAdd As VisioEventHandler    'OnImageDelete event is raised when an image is deleted from the Visio drawing    Public Event OnImageDelete As VisioEventHandler    'OnImageDoubleClick event is raised when the user double clicks an image from the Visio drawing    Public Event OnImageDoubleClick As VisioEventHandler    'AddAdvise method adds an Event object to the EventList collection of the     'source object whose events you want to receive. When selected events occur,     'the source object will notify your event handler.    Public Function AddAdvise(ByVal sourceApplication As _    Microsoft.Office.Interop.Visio.Application, ByVal sourceDocument As Document)       visioApplication = sourceApplication       visioDocument = sourceDocument       'Add the events that need to be responded to the behavior of the Visio objects.        Dim newEvent As [Event]       Dim applicationEvents As EventList = visioApplication.EventList       Dim documentEvents As EventList = visioDocument.EventList       'Add the image-added event to the document. The new image will be available for processing in the handler.         Dim addimageEventCode As Short = -32704       newEvent = documentEvents.AddAdvise(addimageEventCode, Me, "", "")       'Add the image-deleted event to the document. This event executes        'when an image is deleted from the document.       'The deleted image will still be available for processing in the handler.       Dim deleteimageEventCode As Short = VisEventCodes.visEvtShape + VisEventCodes.visEvtDel       newEvent = documentEvents.AddAdvise(deleteimageEventCode, Me, "", "")       'Add marker events to the application. This event executes        'when a user double clicks an image from the visio drawing.       Dim doubleclickEventCode As Short = VisEventCodes.visEvtApp + VisEventCodes.visEvtMarker       newEvent = documentEvents.AddAdvise(doubleclickEventCode, Me, "", "")    End Function    'The IVisEventProc.VisEventProc function is called by Visio     'when an event which has been added to an events list collection has been raised.    Public Function VisEventProc(ByVal nEventCode As Short, ByVal pSourceObj As Object, _    ByVal nEventID As Integer, ByVal nEventSeqNum As Integer, ByVal pSubjectObj _    As Object, ByVal vMoreInfo As Object) As Object _       Implements  Microsoft.Office.Interop.Visio.IVisEventProc.VisEventProc       Dim Image As Shape       If TypeOf pSourceObj Is Microsoft.Office.Interop.Visio.Application Then          visioApplication = pSourceObj          ElseIf TypeOf pSourceObj Is Document Then          visioDocument = pSourceObj       End If       'Check for each event code that is handled. The event codes are a        'combination of an object and an action.       'As VisEventCodes.visEvtAdd cannot be converted to short value,        'the value for event code for adding image is taken as -32704 which is a short value       Dim addimageEventCode As Short = -32704       Dim deleteimageEventcode As Short = VisEventCodes.visEvtShape + VisEventCodes.visEvtDel       Dim doubleclickimageEventCode As Short = VisEventCodes.visEvtApp + _        VisEventCodes.visEvtMarker       If nEventCode = addimageEventCode Then          'Handle the add image event          Image = CType(pSubjectObj, Shape)          handleImageAdd(Image)          ElseIf nEventCode = deleteimageEventcode Then          'Handle the delete image event          Image = CType(pSubjectObj, Shape)          handleImageDelete(Image)          ElseIf nEventCode = doubleclickimageEventCode Then          'Handle the double-click event       End If    End Function    'This procedure is called when an image is added on the Visio drawing    Public Sub handleImageAdd(ByVal addedImage As Shape)       'Ignore the image add event that occurs when the user groups existing images in the Visio drawing.       'This is done to prevent an OnImageAdd event from being raised that        'would cause the existing images to be counted more than once.       If Not visioApplication.IsInScope(Microsoft.Office.Interop.Visio.VisUICmds.visCmdObjectGroup) Then          RaiseEvent OnImageAdd()       End If    End Sub    'This procedure is called when an image is deleted from the visio drawing    Public Sub handleImageDelete(ByVal deletedImage As Shape)       RaiseEvent OnImageDelete()    End Sub End Class 

 

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In the above listing, the VisioEvents class implements the Microsoft.Office.Interop.Visio.IvisEventProc interface to trap the events. The VisioEvents class traps the events when the end user adds an image on the Visio drawing, deletes an image from the Visio drawing, and double-clicks an image on the Visio drawing. The VisioEvents class provides the AddAdvise method that adds an Event object to the EventList collection of the Visio drawing control. When a particular event occurs, the drawing control specifies the corresponding event handler.

Creating the VisioMethods Class

The VisioMethods.vb file defines the VisioMethods class that defines methods to execute operations commonly performed on Visio objects.

Listing 6-5 shows the code for the VisioMethods.vb that defines the VisioMethods class:

Listing 6-5: The VisioMethods.vb File

 Imports Microsoft.Office.Interop.Visio Imports System.IO Public Class VisioMethods    'The MapVisioToWindows function converts Visio coordinates to Windows coordinates    Public Shared Function MapVisioToWindows(ByVal drawingControl As _    AxMicrosoft.Office.Interop.VisOcx.AxDrawingControl, ByVal visioX As Double, _    ByVal visioY As Double) As System.Drawing.Point       If drawingControl Is Nothing Then          MsgBox("Invalid control", MsgBoxStyle.OKOnly, "Null Reference")          Exit Function       End If       Dim windowsX As Integer       Dim windowsY As Integer       Dim visioLeft As Double       Dim visioTop As Double       Dim visioWidth As Double       Dim visioHeight As Double       Dim pixelLeft As Integer       Dim pixeltop As Integer       Dim pixelWidth As Integer       Dim pixelHeight As Integer       Dim referenceWindow As Window = drawingControl.Window       'Get the window coordinates in Visio units       referenceWindow.GetViewRect(visioLeft, visioTop, visioWidth, visioHeight)       'Get the window coordinates in pixels       referenceWindow.GetWindowRect(pixelLeft, pixeltop, pixelWidth, pixelHeight)       'Convert the X-coordinate by using pixels per inch from the width values       windowsX = pixelLeft + ((pixelWidth / visioWidth) * (visioX - visioLeft))       'Convert the Y-coordinate by using pixels per inch from the height values and transform from        'a top-left origin (Windows coordinates) to a bottom-left origin (Visio coordinates).       windowsY = pixeltop + ((pixelHeight / visioHeight) * (visioTop - visioY))       Return New System.Drawing.Point(windowsX, windowsY)    End Function    'The getClickedImage method finds an image at the specified location    'If there are more than one image at the location the top image in Z order is returned    Public Shared Function GetClickedImage(ByVal drawingControl As _    AxMicrosoft.Office.Interop.VisOcx.AxDrawingControl, ByVal VisioX As Double, _    ByVal VisioY As Double) As Shape       If drawingControl Is Nothing Then          MsgBox("Invalid control", MsgBoxStyle.OKOnly, "Null Reference")          Exit Function       End If       'A shape object       Dim shape As Shape       Dim currentPage As Page = drawingControl.Window.Page       'Use the spatial search method to return a list of images at the clicked location.       Dim foundImages As Selection = currentPage.SpatialSearch(VisioX, VisioY, _       CShort(VisSpatialRelationCodes.visSpatialContainedIn), 0.0001, _       CShort(VisSpatialRelationFlags.visSpatialBackToFront))       'If there is more than one image on the selected location return the top most images       If foundImages.Count > 0 Then          shape = foundImages(foundImages.Count)       End If       Return shape    End Function    'The SaveDrawing method to save changes to the Visio document.     'The user is prompted before saving the visio drawing.     'This method returns the id of the message box that has closed the dialog result    Public Shared Function SaveDrawing(ByVal drawingControl As _    AxMicrosoft.Office.Interop.VisOcx.AxDrawingControl, _    ByVal promptFirst As Boolean) As DialogResult       Dim saveFileDialog As SaveFileDialog       Dim result As DialogResult       Dim targetFilename As String       Dim targetDocument As Document       Try          targetFilename = drawingControl.Src          'Extracting the file name instead of the full path of the file          targetFilename = targetFilename.Substring(targetFilename.LastIndexOf("\") + 1)          targetDocument = drawingControl.Document          'If prompting first is true          If promptFirst = True Then             Dim promptMessage As String             Dim title As String = "Save As"             'saving changes to existing drawing             If targetFilename.Length > 0 Then                promptMessage = "Save changes to : " & targetFilename & " ?"                Else                'saving changes as new drawing                promptMessage = "Save changes to current document ?"             End If             result = MsgBox(promptMessage, MsgBoxStyle.YesNoCancel, "Save Changes")             Else             result = DialogResult.Yes          End If          'Display a file browse dialog box to select path and filename.          If result = DialogResult.Yes And targetFilename.Length = 0 Then             'Set up the save file dialog and let the user specify the name to save the drawing.             saveFileDialog = New SaveFileDialog             saveFileDialog.Title = "Save As"             Dim currentDirectory As Directory             Dim currentPath As String             currentPath = currentDirectory.GetParent(currentDirectory.GetCurrentDirectory).ToString             saveFileDialog.InitialDirectory = currentPath             If saveFileDialog.ShowDialog() = DialogResult.OK Then                targetFilename = saveFileDialog.FileName             End If          End If          'Save the Visio drawing to the filename specified by the end user in           'the save file dialog, or the existing file name.          If result = DialogResult.Yes And targetFilename.Length > 0 Then             targetDocument.SaveAs(targetFilename)             drawingControl.Src = targetFilename             drawingControl.Document.Saved = True          End If          Catch ex As Exception       End Try       Return result    End Function End Class 

 

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In the above listing, the MapVisioToWindows method provides the functionality to map the Visio co ordinates to Window co ordinates. The SaveDrawing method provides the functionality to save the Visio drawing and the GetClickedImage method retrieves the image selected by the end user in the drawing control.