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This is a significant difference between Windows Forms and WPF. WPF s Control class (the one in System.Windows.Controls, as opposed to the Windows Forms one in System.Windows.Forms) is more specialized, as you saw in 20. In Windows Forms, not only do interactive elements such as Button derive from Control, so do layout elements. The nearest equivalent to the Windows Forms Control class in WPF and Silverlight is actually FrameworkElement.download barcode font excel 2003, excel 2010 barcode add in, barcode font for excel 2007, excel formula barcode check digit, how to use barcode font in excel 2010, create barcode in excel 2013 free, 2d barcode font for excel, convert text to barcode in excel 2016, barcode font excel 2010 free, barcode add in excel 2013,
Our application is going to have a list of entries at the top, and some fields to edit the selected entry at the bottom We ll use a SplitContainer to arrange these two sections SplitContainer provides a draggable splitter bar that can be used to resize a pair of panels sharing some space on-screen We add this by dragging it from the Toolbox s Containers section onto the form It automatically fills the whole window However, it splits the window with a vertical splitter the two halves are on the left and right, but we wanted them on the top and bottom This is easily fixed, because like many controls, the SplitContainer offers a pop-up window for performing common tasks At the top-righthand corner of the control, a little arrow in a box appears, and if we click on this, the pop up appears, as Figure 22-3 shows.
Clicking Horizontal splitter orientation gives use the orientation we require In the top half of the UI, we want a list showing each to-do entry We re likely to want to show at least a couple of pieces of information the entry title and its due date, for example The simple ListBox control is not sufficient here Unlike the WPF ListBox, Windows Forms cannot easily add multiple columns, because it s based on the Win32 ListBox It wouldn t be completely impossible as you can write code that customizes how each item is rendered, but that seems like an unnecessarily complex solution when the ListView provides multicolumn list support While ListView is the right control for presenting the information to the user, we just caused ourselves a problem.
When the application is running, the log window is shown next to a window containing the event widget. A sample log is shown in Figure 6-5. All events are listed, and selected parameters are shown for some events. For example, the text is shown for QKeyEvent events, and the position of the pointer is shown for QMouseEvent events.
Support for data binding in Windows Forms is somewhat uneven, and while you can data-bind a ListBox, you can t do that with ListView This puts us in a tricky situation: either we use a ListBox, compromising the UI to make life easier for us, the developers, or we have to do more work by hand to use the ListView, in order to do right by the end user Or we could use a data grid, but for such a simple application, it seems like overkill the ListView is something all Windows users will be familiar with, and it fits the bill And because it means doing a few things.
by hand, it also gives us an opportunity to explore a few details of the data binding system that we might otherwise not have seen, so we ll go with that. The ListView control is in the Common Controls section of the Toolbox. When we drag it onto the top panel in the SplitContainer, we need to fix a few things with the Tasks pop up. First, we want the list view to fill the whole of the top panel there s a Dock in parent container task just for that. We also have to change its View the default is LargeIcon, but we need to change that to Details for the multicolumn view we want. And finally, we need to tell it about the columns, by clicking the Edit Columns task.
The ColumnHeader Collection Editor opens. Clicking Add a couple of times adds two columns. As Figure 22-4 shows, Visual Studio has been characteristically unadventurous with the names columnHeader1 and columnHeader2 don t say much. These are the names it will give to the fields that make these objects accessible to us in the code behind. It s usually a good idea to provide more informative names each time you add anything in the Windows Forms designer whether it s a control, a nonvisual component, or a column like this. Otherwise, your program rapidly acquires a long list of incomprehensible identifiers. So we ll set the (Name) on the right to titleColumn for the first column, and dueDateColumn for the second. Of course, we also want the displayed text in the column headers to be a bit more useful than the default, ColumnHeader, so we ll change the Text property of the two columns to Title and Due Date, respectively. Finally, to ensure that the two columns make reasonably good use of the space initially available, we ll set their Width properties to 200 and 70. Figure 22-5 shows how the form looks once this is done. We haven t given the ListView itself a good name yet, so we ll call it entriesListView.