Virtual Developer Workshop: Containerized Development with Docker
In this tutorial you are going to learn how to get your Microsoft WPF (Windows Presentation Foundation) application to open in its last location before it was closed. You are going to do this using VB.NET code and application settings.
- Create a new WPF application project. Ensure that it is a Visual Basic project type. Name it 'Location'.
- Once your project is created place a Label control in the window and change its Content property to "I was Here".
- Change the TextSize property of the label in the Text section of the properties window to 20. Resize the label if you need to to make the text visible and drag the label until it is at about the center of the window.
- Select Window1 and in the
CommonPropertiessection of the Properties window ensure that the
WindowStartupLocationis set to Manual.
- Right click on the Location project in the Solution
Explorer and select properties from the context menu or
double click the
MyProjectfile in the project tree. This opens the properties window.
- Select the Settings tab. Notice that there is a default
setting that is already present. Right click inside the
first cell and select 'Add Setting' from the context menu.
The default text is selected. Type in the text
- Select double from the Type dropdown list and leave the Scope as user. Leave the Value cell as is.
- In the second row type '
LastTop' in the Name section and select a Type of Double. Leave the Scope and Value section as default. Save your work.
- Double click on Window1.xaml.vb in the project tree to open the code behind file.
- Select 'Window1 Events' from the
ClassNamecombo box and the Closing event from the
- In the Window1_Closing event procedure type the following code;
- Select Window1 Events from the
ClassNamecombo box and the Loaded event from the
MethodNamecombo box. Type in the following code in the
- Run the application by pressing F5 or by clicking on the Start Debugging button.
- Drag the window to a different part of your screen and close it.
- Run the application again by pressing the F5 key. Notice that the window opens in the last location where you closed it.
Now you are going to add some code to make use of the previously created settings. We will be using the My.Settings keyword and the Left and Top window properties which get or set the position of the window's left and top edges in relation to the desktop.
With My.Settings .LastLeft = Me.Left .LastTop = Me.Top .Save() End WithYour Window1 class should now look like this;
Class Window1 Private Sub Window1_Closing(ByVal sender As Object, _ ByVal e As System.ComponentModel.CancelEventArgs) _ Handles Me.Closing With My.Settings .LastLeft = Me.Left .LastTop = Me.Top .Save() End With End Sub End Class
Me.Left = My.Settings.LastLeft Me.Top = My.Settings.LastTopClick on the Save All button or press
My.Settings.Save ( ) allows us to persist the application settings when Window1 is closed. This ensures that the window will open in the last location where it was closed since we set the Left and Top properties of Window1 to the LastLeft and LastTop settings in the
Window1_Loaded event procedure.
Thanks for reading!