s WINDOWS FORMS UI in VB.NET

Drawer PDF 417 in VB.NET s WINDOWS FORMS UI

As you can see, this form has a set of Label and TextBox controls so the user can view and edit information in the Project object itself. It also uses a DataGridView control to display the ProjectResource objects. That DataGridView will also allow the user to change the role a resource plays on a project. Additionally, the values in the FullName column will be displayed as hyperlinks to make it easy for the user to bring up the associated ResourceEdit user control for that resource. Implementing the functionality behind this form is more complex than RolesEdit or ResourceSelect. But still, the focus is entirely on user interaction and the flow of the UI, not on authorization, validation, or other business behaviors already implemented in the business objects.

The controls shown in Figure 9-14 were all added using drag-and-drop data binding. The Label and TextBox controls were added by dragging the Project object from the Data Sources window onto the designer, after setting some options in the Data Sources window.

Figure 9-15 shows the Data Sources window with the Projects node expanded and being changed to create a details form.

Notice the icon next to the Project node: it represents a details form rather than the default grid display icon you see next to ProjectList, Resource, and the other object nodes. This change occurred because I chose the Details option from the menu for the Project node. When an object is set to use details mode, the individual control types of the properties for that object come into play. When the object is dragged onto the designer, controls for each property will be created. In fact, a pair of controls is created: a Label displaying the property name and another control to display the property value itself. This second control is indicated by the icons you see next to each property node in the Data Sources window. The Id property on a Project object is read-only, and so it should be displayed in a Label rather than an editable control. Figure 9-16 shows how the Id property s control is changed from TextBox to Label.

Once the object node is set to details mode and all its properties are set to use the correct control types, the object is simply dragged onto the designer. Visual Studio creates a ProjectBindingSource, all the controls for the properties, and of course the BindingNavigator control.

You can then resize and reposition the controls to get the display you require. The layout in Figure 9-14 shows the result after I ve repositioned the controls, resized them, set their Anchor properties, and changed their tab order to match the new layout. And of course, I ve removed the BindingNavigator control. But at no point did I need to worry about setting up the data binding for any controls; Visual Studio handled that automatically. My only concern is the appearance of the UI itself.

If you prefer, you could put the controls on the form manually, directly from the toolbox. Then you could use connect-the-dots binding to drag each object property from the Data Sources window onto the controls to set up the data binding. Or if you really like manual work, you could manually set the data properties on each control through the Properties window. Regardless of which approach you take, the results are the same: the controls are data bound to the ProjectBindingSource control, which in turn will be bound to a Project object.

You may be wondering why the Started and Ended properties are bound to TextBox controls rather than a specialized date-entry control. As discussed in 5, it is often preferable to allow the user to enter dates as he or she chooses especially for heads-down data entry. Given the extra parsing capabilities of SmartDate, this makes even more sense, since the user can simply press -, ., or + to get yesterday, today, or tomorrow s date.