EXTENDING USER EXPERIENCE OF LOB APPLICATIONS in VB.NET

Generation QR Code in VB.NET EXTENDING USER EXPERIENCE OF LOB APPLICATIONS

//Click event to provide print functionality printcustombutton.Click += new RoutedEventHandler(printcustom_Click); panel1.Children.Add(printscreenbutton); panel1.Children.Add(printimagebutton); panel1.Children.Add(printcustombutton); border.Child = panel1; contextMenu.Child = border; //set display location to current cursor contextMenu.VerticalOffset = e.GetPosition(null).Y; contextMenu.HorizontalOffset = e.GetPosition(null).X; //show the context print menu contextMenu.IsOpen = true; } As you can see here, we have added three buttons as part of the pop-up context menu window and made it visible. The position of the pop-up context menu is determined by setting VerticalOffset and HorizontalOffset properties of the pop-up based on the current position of the mouse, which you can get using the MouseButtonEventArgs.GetPosition method. Notice that each button has implemented a Click event to perform the required actions. In this section, we will just display a message box and close the context menu as shown here. In the next section we will implement the actual Printing capability. private void printscreen_Click(object sender, RoutedEventArgs e) { MessageBox.Show("Print Screen Functionality Goes Here.."); contextMenu.IsOpen = false; } private void printimage_Click(object sender, RoutedEventArgs e) { MessageBox.Show("Print Image Functionality Goes Here.."); contextMenu.IsOpen = false; } private void printcustom_Click(object sender, RoutedEventArgs e) { MessageBox.Show("Custom Print Functionality Goes Here.."); contextMenu.IsOpen = false; } If you run the project at this point, you will notice that the Print context menu is displayed upon right-clicking. If you click one of the Print buttons, you will get an appropriate message as shown in Figure 7-6 and close the context menu. However, if you do not click any of the context menu buttons, the context menu will still be visible.

Figure 7-6. Demonstrating Right-Click Context Menu Feature Usually the default behavior is that you can close the context menu upon the left-click event. Let s implement the LayoutRoot_MouseLeftButtonDown event to close the visible context menu pop-up. See the following appropriate XAML code update (in highlighted text) to the Grid control and related codebehind. <Grid x:Name="LayoutRoot" Margin="2" MouseRightButtonDown="LayoutRoot_MouseRightButtonDown" MouseRightButtonUp="LayoutRoot_MouseRightButtonUp" MouseLeftButtonDown="LayoutRoot_MouseLeftButtonDown"> private void LayoutRoot_MouseLeftButtonDown (object sender, MouseButtonEventArgs e) { contextMenu.IsOpen = false; }

One of the most widely requested features for Silverlight is support to the Printing feature. Silverlight 4 introduces this capability and enables you to either print the existing visual tree or create a custom virtual visual tree. The printing functionality can be implemented in both in-browser and out-ofbrowser modes.

The PrintDocument class is the core class that provides printing APIs for Silverlight 4 applications. It resides in the System.Windows.Printing namespace in the System.Windows assembly. This class contains only one method, the Print method, which you will call to open the default Print dialog box to start the printing process for the specified document. You can pass the document name as a string to the Print method, which will be displayed as a document name to the active printer dialog box displaying the document submitted for the printing. The PrintDocument class also has one property, the PrintedPageCount property, that returns the number of pages that have printed. Table 7-3 shows the events of this class, which control the printing process. Table 7-3. Events of the System.Windows.Printing.PrintDocument Class

Occurs after the Print method is called and the print dialog box successfully returns, but before the PrintPage event is raised. If the user cancels the Print dialog box, this event will not raise. You can use this event to handle any activity (showing the printing progress indicator, for example) before the printing starts. The BeginPrintEventArgs provides data for the BeginPrint event. Occurs when the printing operation is completed successfully or the print operation is cancelled by the user. If the user cancels the Print dialog box, this event will not raise. You can use this event to handle any print operation ending activity (making the printing progress indicator invisible, for example) or perform any clean-up operation after the printing finishes. If any error occurs during the printing operation, you can use the EndPrintEventArgs.Error property to get the error information. The default value of EndPrintEventArgs.Error is null. Occurs when each page is printing. After the PrintPage event occurs, the specified PrintPageEventArgs.PageVisual will be sent to the printer to be printed. You set up the PrintPageEventArgs.PageVisual to the layout root element to print the entire screen, or to a specific element to print specific information within the screen. Or you can develop a virtual visual tree and set it up to the virtual tree to print custom developed information. If PrintPageEventArgs.HasMorePages is true, the PrintPage event will occur again. The default value of PrintPageEventArgs.HasMorePages is false.