Microsoft Visual Basic .NET Databases - Lesson 5: List-Based Controls Data Binding

	List-Based Controls Data Binding

Data Display with

Besides the DataGrid, the .NET Framework provides many other controls that are list-based. These include the combo boxes, list boxes, three views, list views, etc. These controls are ready for data display so much that they is little or not code involved but they must be appropriately configured. The list-based controls are usually meant to display data from another table. For this reason, they may use a foreign key that represents a child table. This means that, as done for the master/detail scenario, you should first have a parent, then a child table and the child table must have a foreign key that represents the table of the records that would be displayed on the list-based control.

Practical Learning: Binding Data With a Combo Box

In Server Explorer, under the Tables node of CIC1, right-click Orders and click Design Table
To add a new column, right-click OrderDate and click Insert Column
Change the properties of the new column as follows:
Column Name: EmployeeID
Data Type: int
Allow Nulls: cleared
Default Value: 1
Right-click anywhere in the table and click Relationships...
In the Property Pages, click New
In the Primary Key Table combo box, select Employees
In the first combo box under it, select EmployeeID
In the combo box under Orders, select EmployeeID
Click Close and close the table
When asked whether you want to save, click Yes twice
To add a new form, on the main menu, click Project -> Add Windows Form...
Set the Name to OrderProcessing and press Enter
Change its Icon to the above App.ico and change its Text to
Clarksville Ice Cream - Order Processing
Set its StartPosition to CenterScreen

Design the form as follows:

Control	Name	Text	Additional Properties
Label		Order ID:
TextBox	txtOrderID		ReadOnly: True
Label		Processed By:
ComboBox	cboEmployeeID		DropDownStyle: DropDownList
Label		Order Date:
DateTimePicker	dtpOrderDate		Format: Short
Label		Order Time:
DateTimePicker	dtpOrderTime		Format: Time: ShowUpDown: True
Label		Flavor:
ComboBox	cboFlavorID		DropDownStyle: DropDownList
Label		Container:
ComboBox	cboContainerID		DropDownStyle: DropDownList
Label		Ingredient:
ComboBox	cboIngredientID		DropDownStyle: DropDownList
Label		Scoops:
TextBox	txtScoops	1	TextAlign: Right
Label		Total Order:
TextBox	txtTotalOrder	0.00	TextAlign: Right
Button	btnClose	Close
Button	btnFirst	\| <
Button	btnPrevious	<
Button	btnNext	>
Button	btnLast	> \|

In Server Explorer, under the Table node, click Containers
Press and hold Ctrl
Click Employees, Flavors, Ingredients, and Orders
Release Ctrl
Drag the selection and drop it on the form
On the main menu, click Data -> Generate Dataset...
Accept the Existing radio button
Click OK

On the form, click each control and, in the Properties window, bind it as follows

Control	DataBindings			DataSource	DisplayMember	ValueMember
Control	Text	Value	SelectedValue	DataSource	DisplayMember	ValueMember
txtOrderID	DsIceCream1. Orders.OrderID
cboEmployeeID			DsIceCream1. Orders.EmployeeID	dsOrders1.Employees	LastName	EmployeeID
dtpOrderDate		DsIceCream1. Orders.OrderDate
dtpOrderTime		DsIceCream1. Orders.OrderTime
cboFlavorID			DsIceCream1. Orders.FlavorID	dsOrders1.Flavors	Flavor	FlavorID
cboContainerID			DsIceCream1. Orders.ContainerID	dsOrders1.Containers	Container	ContainerID
cboIngredientID			DsIceCream1. Orders.IngredientID	dsOrders1.Ingredients	Ingredient	IngredientID
txtScoops	DsIceCream1. Orders.Scoops

Double-click an empty area of the form and implement the form's Load event as follows:

Private Sub OrderProcessing_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Me.SqlDataAdapter5.Fill(Me.DsIceCream1)
        Me.SqlDataAdapter4.Fill(Me.DsIceCream1)
        Me.SqlDataAdapter3.Fill(Me.DsIceCream1)
        Me.SqlDataAdapter2.Fill(Me.DsIceCream1)
        Me.SqlDataAdapter1.Fill(Me.DsIceCream1)
End Sub

In the Class Name combo box, select btnClose. In the Method Name combo box, select Click and implement the event as follows:

Private Sub btnClose_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnClose.Click
        Close()
End Sub

In the Class Name combo box, select btnFirst. In the Method Name combo box, select Click and implement the event as follows:

Private Sub btnFirst_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnFirst.Click
        Me.BindingContext(Me.DsIceCream1, "Orders").Position = 0
    End Sub

In the Class Name combo box, select btnPrevious. In the Method Name combo box, select Click and implement the event as follows:

Private Sub btnPrevious_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnPrevious.Click
        Me.BindingContext(Me.DsIceCream1, "Orders").Position = _
        Me.BindingContext(Me.DsIceCream1, "Orders").Position - 1
    End Sub

In the Class Name combo box, select btnNext. In the Method Name combo box, select Click and implement the event as follows:

Private Sub btnNext_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnNext.Click
        Me.BindingContext(Me.DsIceCream1, "Orders").Position = _
        Me.BindingContext(Me.DsIceCream1, "Orders").Position + 1
    End Sub

In the Class Name combo box, select btnLast. In the Method Name combo box, select Click and implement the event as follows:

Private Sub btnLast_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnLast.Click
        Me.BindingContext(Me.DsIceCream1, "Orders").Position = _
        Me.BindingContext(Me.DsIceCream1, "Orders").Count - 1
    End Sub

Display the first form, Form1.vb [Design]
On the Toolbox, click Button and click the form
Change the new button's Text to Order Processing and change its Name to btnOrders
Add another button to the form. Change its Text to Close and its Name to btnClose
Reposition the buttons as follows:

Double-click the Order Processing and implement its Click event as follows:

Private Sub btnOrders_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnOrders.Click
        Dim frmOrders As OrderProcessing = New OrderProcessing
        frmOrders.Show()
End Sub

In the Class Name combo box, select btnClose. In the Method Name combo box, select Click and implement the event as follows:

Private Sub btnClose_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnClose.Click
        End
End Sub

Execute the application and click the different buttons
Close the forms


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