AccuSoft Resource Center

• Preparing the Compiler
• Setting up the Form
• Add the Code
• Running the Application

1. To create the application interface, start Visual Basic. From the New Project window, select the Standard EXE icon and click Open (see below).
   
   
    
2. Once the project is created you should add the ImageGear ActiveX controls to the project.  From the Project menu, select Components to access the list of available controls. Check off the following components:

• AccuSoft ImageGear 14 Core Library

• AccuSoft ImageGear 14 Dialogs Library

• AccuSoft ImageGear 14 Display Library

• AccuSoft ImageGear 14 Formats Library

• AccuSoft ImageGear 14 View Library

Note:  If you do not see a required control in the list, you may need to install the ImageGear ActiveX product.  If you selected to install this product on first use, simply run one of the ImageGear ActiveX samples.  To do this, click Start, Programs, AccuSoft, ImageGear v14, ActiveX, Samples to locate the samples.  Launching an ImageGear sample program will automatically cause the ActiveX product to be downloaded and installed on your machine.



Once you click OK you will see the icons for the ImageGear controls appear in the Controls toolbar (see below).

 

1. From the Tools menu, select Menu Editor. The Menu Editor dialog box will be displayed.
    
2. Add three menu items to the form with the following characteristics:

Caption Open Zoom In Zoom Out

Name mnuOpen mnuZoomin mnuZoomout

 

3. In turn, add each ImageGear control to the form by clicking the appropriate icon in the toolbox and drawing the control on the form. Stretch the PageView control (IGPageViewCtl) to fill most of the form; it should appear as a white rectangle. The remaining controls (IGCoreCtl, IGDisplayCtl, IGFormatsCtl and IGDlgsCtl) should show up as small icons on the form. For this tutorial we will use the default names (e.g. IGCoreCtl1) for each control.  Your form should now look something like this:

 

1. Add the following form declarations and subroutines for Form_Load and Form_Resize:
    

Private currentPage As IGPage
Private currentPageDisp As IGPageDisplay
Private currentFileDialog As IGFileDlg

Private Sub Form_Load()
     On Error GoTo ErrorHandler

     IGCoreCtl1.License.SetSolutionName "AccuSoft 1-100-14"
     IGCoreCtl1.Result.NotificationFlags = IG_ERR_OLE_ERROR

     IGCoreCtl1.AssociateComponent IGFormatsCtl1.ComponentInterface
     IGCoreCtl1.AssociateComponent IGDisplayCtl1.ComponentInterface
     IGCoreCtl1.AssociateComponent IGProcessingCtl1.ComponentInterface

     IGDlgsCtl1.GearFormats = IGFormatsCtl1.ComponentInterface
     IGDlgsCtl1.GearCore = IGCoreCtl1.ComponentInterface
     IGDlgsCtl1.GearDisplay = IGDisplayCtl1.ComponentInterface
     Set currentFileDialog = IGDlgsCtl1.CreateFileDlg

     Set currentPage = IGCoreCtl1.CreatePage
     Set currentPageDisp = IGDisplayCtl1.CreatePageDisplay(currentPage)
     IGPageViewCtl1.PageDisplay = currentPageDisp
 
     IGPageViewCtl1.UpdateView

     Exit Sub
ErrorHandler:
     MsgBox "Errors on stack? " & IGCoreCtl1.Result.isOk & vbCrLf & _
                    Err.Description, vbCritical, "An error has occured"
End Sub

Private Sub Form_Resize()
     If Me.Height > 0 Then
          IGPageViewCtl1.Height = Me.ScaleHeight
     End If
     If Me.Width > 0 Then
          IGPageViewCtl1.Width = Me.ScaleWidth
     End If
End Sub
 

The code above includes the following ImageGear methods and properties:

	IGCoreCtl	License.SetSolutionName	This method of the IGLicense object sets the solution name for the ImageGear license.
		Result.NotificationFlag	This method of the IGResult object tells ImageGear to report errors using the VB ON Error mechanism.
		AssociateComponent	This method associates ImageGear components with the Core control.
		CreatePage	This method creates and returns a new IGPage object.
		Result.isOk	This property of the IGResult object tells if there are any errors on the error stack.
	IGDlgsCtl	GearFormats	This property sets the current Formats control used by the Dialog control.
		GearCore	This property sets the current Core control used by the Dialog control.
	IGDisplayCtl	CreatePageDisplay	This method creates a new IGPageDisplay object for the specified IGPage.
	IGPageViewCtl	PageDisplay	This property sets the current Page Display object displayed by the Page View control.
		UpdateView	This method causes the Page View control to redraw itself.

2. Next, create a click procedure for mnuOpen by clicking the menu on the form or by copying the code below:
    

Private Sub mnuOpen_Click()
     On Error GoTo ErrorHandler

     Dim loadDialogOptions As IGFileDlgPageLoadOptions
     Set loadDialogOptions = _

IGDlgsCtl1.CreateFileDlgOptions(IG_FILEDLGOPTIONS_PAGELOADOBJ)

     If currentFileDialog.Show(loadDialogOptions) Then
          IGFormatsCtl1.LoadPageFromFile currentPage, loadDialogOptions.FileName, _
          loadDialogOptions.PageNum
     End If

     IGPageViewCtl1.UpdateView

     Exit Sub
ErrorHandler:
     MsgBox "Errors on stack? " & IGCoreCtl1.Result.isOk & vbCrLf & _
                    Err.Description, vbCritical, "An error has occured"
End Sub
 

The code above includes the following methods:

	IGDlgsCtl	CreateFileDlgOptions	This method creates a file dialog options object that will contain for example the filename and page number.
	IGFileDlg	Show	This method shows the file dialog and returns True if the user clicked OK.
	IGFormatsCtl	LoadPageFromFile	This method loads an image into the specified IGPage from the specified filename.

3. Finally, add click procedures for the mnuZoomin and mnuZoomout commands by double-clicking on each control respectively, or by copying the code below:
    

Private Sub mnuZoomIn_Click()
     On Error GoTo ErrorHandler

     Dim zoomzoom As IGDisplayZoomInfo
     Set zoomzoom = currentPageDisp.GetZoomInfo(IGPageViewCtl1.hWnd)

     zoomzoom.HZoom = zoomzoom.HZoom * 1.25
     zoomzoom.VZoom = zoomzoom.VZoom * 1.25
     zoomzoom.Mode = IG_DSPL_ZOOM_H_FIXED Or IG_DSPL_ZOOM_V_FIXED
     currentPageDisp.UpdateZoomFrom zoomzoom

     IGPageViewCtl1.UpdateView

     Exit Sub
ErrorHandler:
     MsgBox "Errors on stack? " & IGCoreCtl1.Result.isOk & vbCrLf & _
                    Err.Description, vbCritical, "An error has occured"
End Sub


The above code zooms the image to 125 percent, or 5/4ths, of its size (zoom in by 25 percent).


Private Sub mnuZoomOut_Click()
     On Error GoTo ErrorHandler

     Dim zoomzoom As IGDisplayZoomInfo
     Set zoomzoom = currentPageDisp.GetZoomInfo(IGPageViewCtl1.hWnd)

     zoomzoom.HZoom = zoomzoom.HZoom * 0.8
     zoomzoom.VZoom = zoomzoom.VZoom * 0.8
     zoomzoom.Mode = IG_DSPL_ZOOM_H_FIXED Or IG_DSPL_ZOOM_V_FIXED
     currentPageDisp.UpdateZoomFrom zoomzoom

     IGPageViewCtl1.UpdateView

     Exit Sub
ErrorHandler:
     MsgBox "Errors on stack? " & IGCoreCtl1.Result.isOk & vbCrLf & _
                    Err.Description, vbCritical, "An error has occured"
End Sub


The above code zooms out, decreasing the image to 4/5ths of its size, thereby canceling the effect of the zoom-in above.

The code above includes:

	IGPageDisplay	GetZoomInfo	This method creates and returns a new IGDisplayZoomInfo object that contains zoom mode and values.
		UpdateZoomFrom	This method sets zoom mode and values from the specified IGDisplayZoomInfo object.

That's it! Simply compile and run the ActiveX project and you will have a simple, yet functional image viewer. Add the plug-ins to enable support for over 100 image formats.