Maybe first I will tell about my application.
When for example an employee will log into my application, he will have loaded "Employee Menu":
Dim Empl As New Employee
MainGrid.Children.Add(Empl)
Grid.SetRow(Empl, 1)
This is from Window_Loaded event. Menu is User Control, and there I have few buttons to open and operate another user controls. When I press for example button "Question":
Public Class Employee
Dim mw As New MainWindow
Private Sub btnQuestionAdd_Click(sender As System.Object, e As System.Windows.RoutedEventArgs) Handles btnQuestionAdd.Click
Dim Que As New QuestionAdd
mw.MainGrid.Children.Add(Que)
Grid.SetRow(Que, 2)
Grid.SetColumn(Que, 1)
End Sub
End Class
I don't know why nothing is loading after button_click.....
Is it so hard to navigate main windows grid from other controls?
This is just a guess as you've not provided much information, but I noticed the following issue which may be the culprit.
In your first code snippet, you seem to be creating the employee from the MainForm:
Dim Empl As New Employee
MainGrid.Children.Add(Empl)
Grid.SetRow(Empl, 1)
Your following comment would seem to confirm that assumption:
This is from Window_Loaded event. Menu is User Control, and there I have few buttons to open and operate another user controls. When I press for example button "Question"
And yet, in your Employee class, you are creating a brand new instance of MainWindow and then adding data to it:
Public Class Employee
Dim mw As New MainWindow
Private Sub btnQuestionAdd_Click(sender As System.Object, e As System.Windows.RoutedEventArgs) Handles btnQuestionAdd.Click
Dim Que As New QuestionAdd
mw.MainGrid.Children.Add(Que)
Grid.SetRow(Que, 2)
Grid.SetColumn(Que, 1)
End Sub
End Class
If this observation is correct, then I think you need to go back to the books and understand the concept of classes and instances.
You essentially created a second form (which is hidden because you never explicitly show it) and then modify this second form rather than the original. To prove this hypothesis, try adding the following line of code:
Public Class Employee
Dim mw As New MainWindow
Private Sub btnQuestionAdd_Click(sender As System.Object, e As System.Windows.RoutedEventArgs) Handles btnQuestionAdd.Click
Dim Que As New QuestionAdd
mw.MainGrid.Children.Add(Que)
Grid.SetRow(Que, 2)
Grid.SetColumn(Que, 1)
mw.Show() ' <---
End Sub
End Class
You'll likely see a second form pop up with all of the changes your were expecting on your first form.
As to how to fix this, the easiest path is going to be adding a parameter to your initializer ("Sub New") which accepts the MainForm as a value. You can then assign the value to a field or property (probably just your mw field) and continue on your merry way. This is going to give you headaches down the road, though, so it might be a good time to start learning more about software architecture, especially the concept of separation of concerns.
Related
i have textbox multi way to fill it
i can fill it from keyboard normally and the other way by clicking button i created on forum something like calculator
when i click button 1 the textbox fill by number 1 and so
and i have button name and work should be like enter key
i have event keydown to send the value i fill it on the text box and work fine
but i need the button that called enter work as the event keydown of the textbox
in short word i need to use touchscreen to enter number to textbox and button to send the value of the textbox to my work
If you want to execute the same code at two different occasions you should put your code in a separate method and then call that at will.
By dividing your code like this you improve both readability and debuggability, and you make your code easier to understand and update.
Here's a brief example:
Private Sub TextBox1_KeyDown(sender As Object, e As System.Windows.Input.KeyEventArgs) Handles TextBox1.KeyDown
If e.Key = Key.Enter Then
UpdateStatus("Enter was pressed.") 'Call custom method.
End If
End Sub
Private Sub Button1_Click(sender As System.Object, e As System.Windows.RoutedEventArgs) Handles Button1.Click
UpdateStatus("Button1 was pressed. Hello World!") 'Call custom method.
End Sub
Private Sub UpdateStatus(ByVal Text As String) 'Custom method declaration.
TextBox1.Text = Text
'In here is where you'd put your code.
End Sub
I have 2 forms; MainWindow and OwnerShares. There is a search on MainWindow that looks up what items are being shared. OwnerShares has a search function that looks up the owner details and what they are sharing. On OwnerShares the options are displayed in a ListView. What i want to do is allow the user to double click on a row in ListView and be directed to the MainWindow which runs the SEARCH based on the value that was selected from the ListView. The variable ACEName will be the one that i want to pass to the MainWindow form search.
Private Sub listSearchOwner_MouseDoubleClick(sender As Object, e As MouseButtonEventArgs) Handles listSearchOwner.MouseDoubleClick
Dim ACEName As String
ACEName = listSearchOwner.SelectedItems(0).xShareName
OwnerShares.Close()
End Sub
The name of the search in MainWindow is (cmdSearch_Click). I am currently getting the value that i click on with the above code. I just dont know how to open the MainWindow form and run the search command automatically.
If I read your question correctly you could just call show your form and run your other routine
Private Sub listSearchOwner_MouseDoubleClick(sender As Object, e As MouseButtonEventArgs) Handles listSearchOwner.MouseDoubleClick
Dim ACEName As String
ACEName = listSearchOwner.SelectedItems(0).xShareName
OwnerShares.Close()
MainWindow.show()
' YourMethod or Button here.
End Sub
Approach it this way:
Add a module to your project, if you don't have one.
Create a public variable in the module, e.g.
Public VariableName As DataType
Everytime that you double-click the listview control, assign a value to your variable.
After getting the value stored in the public variable, delete the value to create a room to pass another value again.
That should do the trick.
here is my problem: i have created a main window called mainWindow in XAML (vb.net) and inside i have 2 buttons (valid and stop) and a grid in the center.
I have two others little windows (valid window and stop window) written in XAML (vb.net) which have buttons, textbox...
I want, when i click on valid button or stop button, display the valid window or the stop window inside the grid of my mainWindow, so i have this code in my mainWindow.vb:
enter code here
Private Sub valid_Click(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs) Handles valid.Click
Dim content As Object = valid_.Content /*Classe valid_ (a window in xaml)*/
valid_.Content = Nothing
Me.Grid.Children.Add(content)
End Sub
Private Sub stop_Click(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs) Handles stop.Click
Dim content As Object = stop_.Content
stop_.Content = Nothing
Me.Grid.Children.Add(content)
End Sub
So when i click on button valid in my mainWindow, it's ok it displays the valid window in my grid.
First problem: then when i click on button stop in my mainWindow, the stop window is placed just above the valid window, it is not nice, is there a way to clear the grid before display this second window?
And finally, the biggest problem: i need to click many times on valid button or stop button but when i click the second time i have a null reference exception: Me.Grid.Children.Add(content) content is null after the first call so i am only able to click one time on my button.
How can i fix it in order to click many times on my buttons please?
I give you thanks.
Yet again, someone writes some invalid code and then says why isn't this code working? If you look at your code, you should see something:
Private Sub valid_Click(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs) Handles valid.Click
Dim content As Object = valid_.Content /*Classe valid_ (a window in xaml)*/
Me.Grid.Children.Add(content)
End Sub
I'm guessing that you have a private variable for your Valid Window as you call it: valid. On this line, what are you doing to your variable?:
valid_.Content = Nothing
That's right! You're setting its Content property to null. Therefore, I'm not really sure why you were surprised that it was null after the first attempt.
How can i fix it in order to click many times on my buttons please?
Try removing the line that sets the Content property to null.
UPDATE >>>
Your problem is really caused by the fact that you cannot display any UI element in two places at once. Your whole idea of copying the Window.Content to your DataGrid is entirely wrong, but in the name of brevity, your fix is simply to move your content back to the Window, rather than setting it to null each time. Try something like this:
Private Sub valid_Click(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs) Handles valid.Click
If Me.Grid.Children.Count > 0 Then 'Put content back where it belongs
Dim oldContent = Me.Grid.Children(0)
stop.Content = oldContent
Me.Grid.Children.Remove(oldContent)
EndIf
Dim content As Object = valid_.Content /*Classe valid_ (a window in xaml)*/
valid_.Content = Nothing
Me.Grid.Children.Add(content)
End Sub
Please forgive any code mistakes, as I don't write VB.NET. Also, you'll need to update your other method likewise.
I have a very basic question on vb.NET, so basic that I didn't find any answer elsewhere.
I've written with VB express a code that is a simple form proposing various choices through checkboxes.
These choices have to be registered in an array, which I convert later into a textfile to be Perl-processed.
I'm searching a way to zeroise this big array with loops before use, but in fact I don't know how to execute instructions which wouldn't be triggered by events in my main form.
The frame looks like that :
Public Class Form1
'Variables declaration...
'Several boxes like that :
Private Sub CheckBox1_CheckedChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CheckBox1.CheckedChanged
'Instructions...
End Sub
End Class
To launch this application, I simply click on the associated .exe file.
Basically, my question is :
is there a way to execute instructions that wouldn't be launched by an user event, but immediatly launched when the main Form1 is shown ?
Sorry for being retarded, and thank you in advance if you can help me.
The Form.Load event for instance gets launched as soon as the form is about to be shown :)
The Form will raise a Shown event when it is shown simply handle that:
Private Sub Form_Shown(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Me.Shown
'Instructions...
End Sub
It can be better to do initialisation in the constructor right after the Winforms designer adds the comment: 'Add any initialization after the InitializeComponent() call
I am developing a WPF project in vb.net and have multiple windows in it. When user selects a menu item a new windows opens and the problem is when the user clicks on other menu item the current window should close by itself.
How do i achieve it?
Thanks!
I think you mean this based upon your comment:
Class MainWindow
Public Win3 As Window3 = New Window3()
Private Sub Button1_Click(sender As System.Object, e As System.Windows.RoutedEventArgs) Handles Button1.Click
Win3.Show()
Me.Close()
End Sub
End Class
There are two ways to do this:
If the menu items share the same form then in the form create a subroutine, that you call instead of new, that checks if it is already shown/created and if not opens (as you already have). If it is open reload with the new information.
Otherwise before opening the new form go though the open forms (shown below from this website in C#):
FormCollection fc = Application.OpenForms;
foreach (Form frm in fc) {
//iterate through
}
For each form check if it's name is equal to one of the menu items and if it is close it (after saving if required). Then after you exit the for loop you open the new menu item.