I'm not sure if this is possible after doing a bunch of googling, but hopefully it is. I have an application that pulls a list of information from a MySQL database and populates a listview (Unfortunately, I can't change to a datagrid at this time.) What I'm tasked to do is make it so that when clicking on a certain column, a window will open and, based on the ID of the row that was clicked on, retrieve another set of results from the same database.
The list view is created as such:
Do While result.Read()
Dim siteid = (result.Item("idsite").ToString())
Dim sitename = (result.Item("name").ToString())
Dim last_import_date = (result.Item("import_finished").ToString())
Dim last_import_file = (result.Item("file_name").ToString())
Dim last_line = (result.Item("last_line").ToString())
Dim status = (result.Item("status").ToString())
Dim lv As ListViewItem = ListView1.Items.Add(siteid)
lv.SubItems.Add(sitename)
lv.SubItems.Add(last_import_date)
lv.SubItems.Add(last_import_file)
lv.SubItems.Add(last_line)
lv.SubItems.Add(status)
Loop
So preferably I'd like to click on "Last_import_file" and have that open the window. I've tried a bunch of ItemClicked type commands, but haven't had much luck.
Is what I'm attempting possible? I don't need any special text formatting, just want to register the click and pop open the dialog.
Thanks!
Yes it is possible. To do this in a Listview it is a bit more complicated than a DataGridView. You'll need to make use of the ListViewHitTestInfo class. Using the MouseDown Event of your listview, use this code:
Private Sub ListView1_MouseDown(sender As Object, e As System.Windows.Forms.MouseEventArgs) Handles ListView1.MouseDown
Dim info As ListViewHitTestInfo = ListView1.HitTest(e.X, e.Y)
MsgBox(info.Location.ToString())
If Not IsNothing(info.SubItem) Then
'info will contain the information of the clicked listview column. You can then go through it's subitems for more information, if any.
End If
End Sub
Related
My code creates a 5x5 grid of buttons. I am wanting to give each of these buttons different names "BtnColour1", "BtnColour2", etc. How do I give them all different names and how do I refer to each button later in the program?
Dim bytCounter As Byte
For bytCounter = 1 To 25
Dim btnColour As New Button
Me.Controls.Add(btnColour)
btnColour.Height = 50
btnColour.Width = 50
btnColour.Name = "btnColour" & bytCounter
btnColour.Enabled = False
btnColour.Left = ((bytCounter - 1) Mod 5) * 51
btnColour.Top = ((bytCounter - 1) \ 5) * 51
AddHandler btnColour.Click, AddressOf BtnClick
Your code (I guess you forgot the ending Next) does create 25 Buttons, with names btnColour1... btnColour25.
In the BtnClick event, to get the name of the clicked button, you should write something like:
Private Sub BtnClick(sender As Object, e As EventArgs)
Dim buttonName as string=CType(sender, Button).Name
'buttonName now has the clicked button name
End Sub
Of course, since you set the enabled property to False, your button click event will not fire.
In a general sense (and in addition to Spyros' answer, which is a good way to do it in an event handler - the sender is always the thing that raised the event), when you give a control a name and add it to a control's Controls collection, you can then retrieve it by that name later:
'Here you added the button to the form controls:
Me.Controls.Add(btnColour)
'later in the code you can ask for it back by name, for example:
Dim controls = Me.Controls.Find("btnColour1")
What you get back is an array of Controls. You get an array because Find can search all children (panels inside panels inside groupboxes inside forms etc) and it is thus conceivable that multiple controls in different panels will both have the same name. In your case if you know you only have one control called "btnColour1" it's safe to get it by array index:
Dim control = controls(0) 'controls variable is from the above Find
Lastly, remember that it comes back as a Control, the parent class for all controls. Because you know it's a button, it's safe to cast without check:
Dim button = DirectCast(control, Button)
Remember that if your property is available on the base Control class you don't even need a cast:
'here's a 1 line way to get the text of the button named btnColour1
'Find all controls named btnColour1, take the first, get the text
Dim t = Me.Controls.Find("btnColour1")(0).Text
If you want to refer to the buttons later in the program to change a setting without clicking the button, you can add each button to an array and call each of them with an index number:
Dim buttons(24) As Button
Then as the buttons are created, you can add each button to the array:
Dim bytCounter As Byte
For bytCounter = 1 To 25
Dim btnColour As New Button
Me.Controls.Add(btnColour)
buttons(bytCounter) = btnColour
you can then reference each button and their properties using the index number of the button in the array. You may also want to add a specific tag to each button to make each button more unique using:
btnColour.Tag = bytCounter
I need help. I want to check if user exists by entering their ic number and I want to display another rest of their data by using file in visual basic. Unfortunately, an error occurs while doing that. I need help. If the user exists, then It will display automatically name, email, address and so on but if a user doesn't exist, then it shows message box. Here I attached the image of the display screen and the code. Please help me. Thank you.
Public Class Form1
Private Sub btnSearch_Click(sender As Object, e As EventArgs) Handles btnSearch.Click
Dim userFile As String = "C:\Users\HP\Desktop\userdata.txt"
Dim inputFile As String
If System.IO.File.Exists(userFile) = True Then
Dim objReader As New System.IO.StreamReader(userFile)
Dim intIc As Integer
Dim intCount As Integer = 0
Dim strName As String
Dim strEmail As String
Dim intPhoneNum As String
Dim strAdd1 As String
Dim strAdd2 As String
Dim intPostcode As String
Dim strState As String
Do While objReader.Peek() <> -1
intIc(intCount) = Convert.ToInt64(objReader.ReadLine())
If (intIc(intCount).Convert.ToInt64(objReader.ReadLine())) Then
strName(intCount) = objReader.ReadLine()
strEmail(intCount) = objReader.ReadLine()
intPhoneNum(intCount) = Convert.ToInt32(objReader.ReadLine())
strAdd1(intCount) = objReader.ReadLine()
strAdd2(intCount) = objReader.ReadLine()
intPostcode(intCount) = Convert.ToInt32(objReader.ReadLine())
strState(intCount) = objReader.ReadLine()
lblName.Text = strName
lblEmail.Text = strEmail
lblNum.Text = intPhoneNum
lblAdd1.Text = strAdd1
lblAdd2.Text = strAdd2
lblPostcode.Text = intPostcode
lblState.Text = strState
objReader.Close()
Else
MessageBox.Show("User Does Not Exist")
End If
intCount = intCount + 1
Loop
Else
MessageBox.Show("File Does Not Exist")
End If
End Sub
End Class
Your task, the easy way:
make a new project
add a DataSet to this new project
open the DataSet, in the properties call it something sensible
Right click the surface, add a new datatable, name it Person
Right click the datatable, add a column, name it IC. Right click, add column, name it Name. Keep going until you added all the fields you want to track(email,phone,address1 etc)
save the DataSet
open the form
show the datasources window (view menu.. other windows)
expand the nodes til you can see Person
click the drop down next to Person, switch from DataGridview to Details
drag Person onto the form. Text boxes, labels etc appear. In the tray at the bottom more things appear
add a textbox to the form and call it searchTextBox
add a search button to the form, double click it, add this line of code to the click handler:
personBindingSource.Filter = '[ic] LIKE '" & searchTextBox.Text & "'"
If personBindingSource.Count = 0 Then MessageBox.Show("No records")
double click the form background to add a form load event handler, put this line of code:
If IO.File.Exists("data.xml") Then .ReadXml("data.xml")
switch back to designer, single click the form background and switch to event properties of the form, add a handler to the form closing event:
.WriteXml("data.xml")
That's it, you now have a program that will open, read and fill the DataSet with data from the data.xml file, it will search it when you type something in the ic box, the text boxes use databinding to show values automatically, and when you close the program it will save updates data. The only task now is to load the xml file with data.
When the textboxes were added to the form you should also have seen a bar appear across the top with some left/right controls in and a green plus. Click the green plus, type some data in, click it again, type more data. Navigating back, if you're adding new data, will commit the data. If you're looking at existing data, editing it then navigating will commit it
After you added some data, you can search for existing data using the search box. When you've searched for a single value it should be the only thing shown and the nav will show "1 of 1". To get back to the mode where all data is showing, put a single asterisk in the search box and hit search; it should show the number records in the top bar and you can scroll them with the arrows.
If you already have lots of data in a file, like you use in your question, you can read it in a loop (like you do in your question, except don't use that code exactly cos it has loads of errors) as a one time thing and assign it into the datatable, or you can manipulate it directly into being XML in a text editor. This is easy to do if you have a capable text editor but I'll not offer any particular advice on it in case you don't have a large amount of existing data. Ask a new question if you do
I know that if I want to dynamically create a new instance of an existing form, I can simply do this...
Dim NewForm As New ExistingForm
... and a new instance of all of the controls from ExistingForm will be available in NewForm.
But what if I want to create a new instance of an existing control that's inside a separate existing form?
More specifically, let's say I have 2 forms - FormA and FormB. Inside FormB is an existing panel (we'll call it ExistingPanel). And inside ExistingPanel are several buttons, text boxes, etc., arranged exactly how I want them.
OK, so... inside a button's click event in FormA, I want to do something like this (it doesn't work, obviously, but should give you a good idea as to what I'm trying to accomplish)...
Dim NewExistingPanel As New FormB.ExistingPanel
And then I want NewExistingPanel to contain new instances all of the individual controls from ExistingPanel (so that I can dynamically manipulate each one individually).
So basically, my program will need to create several NewExistingPanels at runtime. And I will need to access each one (and all of its child controls) individually, after they have been created.
How can I accomplish this? I've been experimenting with this for several hours with no luck so far, so figured I'd break down and ask the real professionals :)
When you create a new user control, you could use a dictionary with the tag value as key and the control name as value. Then you can access the control directly by using the IndexOfKey method.
Dim NewForm2 As New Form2
Dim ControlIndex As New Dictionary(Of String, String)
For I = 0 To 2
Dim NewPanel As New WindowsControlLibrary2.MyCustomPanel
NewPanel.Name = "Panel-" + I.ToString
NewPanel.Location = New Point(0 + (NewPanel.Size.Width * I), 0)
NewPanel.Tag = "MyTagValue" + I.ToString
ControlIndex.Add(NewPanel.Tag, NewPanel.Name)
NewForm2.Controls.Add(NewPanel)
NewForm2.Update()
Next
NewForm2.Show()
Dim CurrentPanel As WindowsControlLibrary2.MyCustomPanel =NewForm2.Controls(NewForm2.Controls.IndexOfKey(ControlIndex("MyTagValue1")))
To add control such as panel with textboxes ang button in it ..
In your project - Add > Usercontrol -->
in this part you can make panel with textboxes and button as you want
name it as "myPanel" and save it as "myPanel.vb" --> or whatever you want
In your form and the button named button1 you can add to your button1_click event :
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
Dim mypanel1 As New MyPanel
mypanel1.Location = New Point(0, 0)
Controls.Add(mypanel1)
mypanel1.TextBox1.Text = "Hi, Im new"
End Sub
And you will get your panel at runtime ...
And you will get the textbox1.text fill with "Hi, I'm new" ...
You could create a user control that lays out your sub-controls the way you want them, then create new instances of that. Add New > User Control in the solution menu, then build, and your controls should be ready to drag into the designer at the top of the Toolbox or to instantiate in code like any other control.
To expand on my comment:
Private somePanels As New Dictionary(Of String, YourUserControl)
Then you can just add them as follows:
Dim c As New YourUserControl()
…
Me.Controls.Add(c)
somePanels.Add("SomeTag", c) ' Instead of using Tag; if your tags are numbers, use a List instead of a Dictionary
And access them as:
Dim c = somePanels("SomeTag")
I have an application written in VB.NET that reads data from a file and displays the data on the screen.
Depending on the data in the file, the program has a TabControl with up to 3 tabs and each tab in turn has a DataGridView for displaying data. For example I have a TabControl that has a tab called "Saturday" and a tab called "Sunday".
The problem I am having is that when I read data from a file, the program displays all the data on the Saturday's tab grid because I am not sure how to reference the Grid on the Sunday tab.
To add the DataGridView I am using the following code:
Grid = New DataGridView
Grid.Dock = DockStyle.Fill
Grid.Name = "Grid" & TabControl.SelectedIndex
Grid.Tag = "Grid" & TabControl.SelectedIndex
And this is how I am reading the data in:
If reader.GetAttribute("controltype") = "Tab" Then
SelectedTab = reader.Name
End If
If reader.Name = "cell" Then
y = y + 1
Grid.Rows(i).Cells(y).Style.BackColor = Color.FromName(reader.ReadElementString("cell"))
End If
What I almost want to do is something like (pseudocode):
SelectedTab.Grid.Rows(i).Cells(y).Style.BackColor = Color.FromName(reader.ReadElementString("cell"))
However when I use the above code it complains:
'Grid' is not a member of 'String'
I hope you understand the issue. Let me know if you need clarification
Your code is a little unclear. However, it appears to me that the following line:
If reader.GetAttribute("controltype") = "Tab" Then
SelectedTab = reader.Name
End If
is creating at least one problem. It looks like you are attempting to refer to a Tabpage control by the string representation of its name, but unless I missed something, what that line is actually doing is trying to make a tabpage control type("SelectedTab") refer to a string type. If that is the case, then you will want to try this instead:
If reader.GetAttribute("controltype") = "Tab" Then
TabControl1.SelectedTab = TabControl1.TabPages(reader.name)
End If
It is a little hard to tell from the code you have posted, but that might get you headed down the right path.
++++++++++++
UPDATE: It appears from your code that you are naming each DGV control by appending the index of the tab on which it is located to the string "grid." I am going to assume that you are using a class member variable named "SelectedTab" to represent the current tab selected in the control. I will assume that at the top of your class you have done something like this:
'Form-or-class scoped memebr variables:
Private SelectedTab As TabPage
Private SelectedGrid As DataGridView
You should be able to refer to the active grid control using something like this:
Private Sub TabControl1_SelectedIndexChanged(sender As Object, e As System.EventArgs) Handles TabControl1.SelectedIndexChanged
' Set SelectedTab member variable to refer to the new selected tab page:
SelectedTab = TabControl1.SelectedTab
' Set the SelectedGrid to refer to the grid control hosted on the selected tab page:
SelectedGrid = TabControl1.SelectedTab.Controls("Grid" & TabControl1.SelectedIndex.ToString())
End Sub
From here, you should be able to use the member variable for SelectedGrid to refer to the grid present on which ever tab page is selected in your tab control.
It is challenging to address your concerns with only fragments of your code. If you have additional difficulties, please post more of your code, so we can better see what else is going on.
Hope that helps!
Okay, I would go about something like this. Maybe you can simply use a DataSet to load the XML data in one line (if they have been saved with DataSet.WriteXML before).
Dim ds As New DataSet
Dim p As TabPage
Dim gv As DataGridView
ds.ReadXml("F:\testdata.xml")
For i As Integer = TabControl1.TabPages.Count - 1 To 0 Step -1
TabControl1.TabPages.RemoveAt(i)
Next
For Each dt As DataTable In ds.Tables
p = New TabPage(dt.TableName)
gv = New DataGridView
' ... configure the gv here...
gv.AutoGenerateColumns = True
gv.Dock = DockStyle.Fill
' ...
gv.DataSource = dt
TabControl1.TabPages.Add(p)
p.Controls.Add(gv)
Next
My problem is: I have a stripped down default.aspx page. Aside from a element, almost ALL the functionality has to be in the code-behind in aspx.vb.
The program retreives information from a database and compares this to another list of tables, number of both lists can vary.
So I need to "bind" a dynamic number of RadioButtonLists to the asp:table element controls, and I need to create a dynamic number of ListItems to each RadioButtonList created. Later, I need to be able to access the selected value of each in order to decide future functions in the database.
An example of the code is like this:
aspx file:
<asp:table ID="table1" runat="server">
aspx.vb file (code-behind):
Sub createHtmlTables()
For i = 0 To productIndex.Count - 1
''//create a RadioButtonList for each i
Dim row As New TableRow
Dim cell As New TableCell
For k = 0 To productTypeAmountIndex.Count - 1
''//create a ListItem(radiobutton)
''//for each k and include it in the RadioButtonList
''//assign a value (for example name) of the product as
''//the ListItems ID to retreive it later
Next
''//add the RadioButtonList to cell.controls etc
Table1.Rows.Add(row)
Next
End Sub
Sub addToDb()
For i = 0 To productIndex.Count - 1
''//get the RadioButtonList for each i
''//and return the value of the selected radiobutton
''//within the list to a variable
Next
End Sub
Sorry if this is long and confusing, but as I can't even form my questions right yet, I tried to include as much information as possible. Basically I just need an example of how and which methods to use to get all that working.
Update:
Everyone keeps telling me that going for tables to begin with was a mistake, but some place I found claimed that you can't customize datagrid looks as easily as you can with tables. I guess I'll start the whole thing from scratch then.
Thing is that the UI should be as graphically pleasing as possible, with the tables I can do all sorts of neat things such as colouring the cells according to the information inside etc.
Anyway, thanks but not what I was looking for but I'll try to remake the thing with datagrid / gridview and see what happens. Might take a few days before I learn enough of them to use them and get back here.
Rather than a table, you'll have better luck with a true server control like gridview or datagrid, or repeater. Then you can just wire up the datasource property on your control.
For all dynamic controls, remember that you have to recreate them every time you do a postback. This may sound odd, but the trick is the every request to the server, including postbacks, uses a different instance of your page class. When that request/postback finishes the page instance used for that request is destroyed. The only things left active are the session and the cache.
This is my .aspx code.
<asp:Table ID="Questions" runat="server">
</asp:Table>
<asp:Button ID="SaveButton" runat="server" Text="Save" />
This is my code behind file code.
I have added dynamic drop-down list.
On save button click, I am retrieving selected value.
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim NewRow As New TableRow
Dim NewCell As New TableCell
Dim rblOptions As New RadioButtonList
rblOptions.ID = "Option1"
rblOptions.Items.Add(New System.Web.UI.WebControls.ListItem("1", "1"))
rblOptions.Items.Add(New System.Web.UI.WebControls.ListItem("2", "2"))
rblOptions.Items.Add(New System.Web.UI.WebControls.ListItem("3", "3"))
NewCell.Controls.Add(rblOptions)
NewRow.Cells.Add(NewCell)
'Questions is a table
Questions.Rows.Add(NewRow)
End Sub
Protected Sub SaveButton_Click(sender As Object, e As EventArgs) Handles SaveButton.Click
If Page.IsValid Then
Dim rbl As RadioButtonList = DirectCast(Questions.FindControl("Option1"), RadioButtonList)
If rbl.SelectedValue.ToString = "ExpectedValue" Then
End If
End If
End Sub