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Property returns different value than what was set

I am working on a Visual Studio extension and my current goal is to set up a menu item in the Tools menu. When clicked on this menu item will open a WinForms window containing a ListView, 3 textboxes, and a button. The idea is when you click on one of the rows in the ListView the data from that row will be populated in the textboxes so that you can update it. If you click the button a new row is added and the textboxes are cleared. However, I'm having an issue with getting the index of the row that I've selected.
private int _index;
private void newSourceBtn_Click(object sender, EventArgs e)
{
// Add new row to the ListView
ListViewItem row = new ListViewItem();
row.SubItems.Add("new");
row.SubItems.Add(String.Empty);
row.SubItems.Add(String.Empty);
remoteSourceListView.Items.Add(row);
int index = remoteSourceListView.Items.Count - 1;
remoteSourceListView.Items[index].Selected = true;
newSourceAdded = true;
sourceNameTextBox.Clear();
sourceUrlTextBox.Clear();
}
public void SourceName_TextChanged(object sender, EventArgs e)
{
remoteSourceListView.Items[IndexSelected].SubItems[1].Text = sourceNameTextBox.Text;
}
public void SourceURL_TextChanged(object sender, EventArgs e)
{
string url = sourceUrlTextBox.Text;
if ((url.StartsWith("http")) || (url.StartsWith("https")) || (url.StartsWith("git")))
{
sourceBranchTextBox.Enabled = true;
}
remoteSourceListView.Items[IndexSelected].SubItems[2].Text = url;
}
public void SourceBranch_TextChanged(object sender, EventArgs e)
{
}
public void SourcesListView_SelectedIndexChanged(object sender, EventArgs e)
{
ListView.SelectedListViewItemCollection selectedRows = remoteSourceListView.SelectedItems;
foreach (ListViewItem row in selectedRows)
{
sourceNameTextBox.Text = row.SubItems[1].Text;
sourceUrlTextBox.Text = row.SubItems[2].Text;
IndexSelected = row.Index;
if (row.SubItems[3].Text != "")
{
sourceBranchTextBox.Enabled = true;
sourceBranchTextBox.Text = row.SubItems[3].Text;
}
}
}
public int IndexSelected
{
get { return _index; }
set { _index = value; }
}
This code shows the button click event which adds the new row to the ListView, the text changed events for each of the textboxes which updates the row in the ListView (sorta), and the selected index changed event for the ListView which is where I'm getting the index of the row that was just selected. While debugging, I noticed that when I click on a row I'm getting the correct index in the selected index changed event; however, when I call IndexSelected from either of the text changed events it is always giving me a different index.
Any suggestions?

From the code posted I can't find any reason that explain the behavior documented.
A possible reason could be the insertion/deletion of new/existing ListViewItem in a position before the saved RowIndex.
However another approach is possible. Instead of keeping the RowIndex you could try to set a global property to the ListViewItem selected and reuse this instance when you need to set its subitems.
In this way you avoid problems if the number of ListViewItems change and some item is inserted/removed before the saved RowIndex. However a safeguard against a null value should be provided.
private ListViewItem CurrentItemSelected {get;set;}
......
public void SourcesListView_SelectedIndexChanged(object sender, EventArgs e)
{
ListView.SelectedListViewItemCollection selectedRows = remoteSourceListView.SelectedItems;
foreach (ListViewItem row in selectedRows)
{
sourceNameTextBox.Text = row.SubItems[1].Text;
sourceUrlTextBox.Text = row.SubItems[2].Text;
CurrentItemSelected = row;
if (row.SubItems[3].Text != "")
{
sourceBranchTextBox.Enabled = true;
sourceBranchTextBox.Text = row.SubItems[3].Text;
}
}
}
public void SourceName_TextChanged(object sender, EventArgs e)
{
if(CurrentItemSelected != null)
CurrentItemSelected.SubItems[1].Text = sourceNameTextBox.Text;
}
However, I am a bit perplexed by your code. Do you have the property MultiSelect set to true? Because if it is set to false then your code doesn't need to loop.
public void SourcesListView_SelectedIndexChanged(object sender, EventArgs e)
{
if(remoteSourceListView.SelectedItems.Count > 0)
{
// With MultiSelect = false; there is only one selected item.
CurrentItemSelected = remoteSourceListView.SelectedItems[0];
sourceNameTextBox.Text = CurrentItemSelected.SubItems[1].Text;
sourceUrlTextBox.Text = CurrentItemSelected.SubItems[2].Text;
if (CurrentItemSelected.SubItems[3].Text != "")
{
sourceBranchTextBox.Enabled = true;
sourceBranchTextBox.Text = CurrentItemSelected.SubItems[3].Text;
}
}
}

Display the selected row from listview to textBox?

How to display the selected row from listview to textBox?
This is how I do int dataGridView:
private void dataGridView1_CellClick(object sender, DataGridViewCellEventArgs e)
{
dataGridView1.Rows[e.RowIndex].ReadOnly = true;
if (dataGridView1.SelectedRows.Count != 0)
{
DataGridViewRow row = this.dataGridView1.SelectedRows[0];
EmpIDtextBox.Text = row.Cells["EmpID"].Value.ToString();
EmpNametextBox.Text = row.Cells["EmpName"].Value.ToString();
}
}
I tried this:
private void listView1_SelectedIndexChanged(object sender, EventArgs e)
{
ListViewItem item = listView1.SelectedItems[0];
if (item != null)
{
EmpIDtextBox.Text = item.SubItems[0].Text;
EmpNametextBox.Text = item.SubItems[1].Text;
}
}

You may want to check if there is a SelectedItem first. When the selection changed, ListView would actually unselect the old item then select the new item, hence triggering listView1_SelectedIndexChanged twice. Other than that, your code should work:
private void listView1_SelectedIndexChanged(object sender, EventArgs e)
{
if (listView1.SelectedItems.Count > 0)
{
ListViewItem item = listView1.SelectedItems[0];
EmpIDtextBox.Text = item.SubItems[0].Text;
EmpNametextBox.Text = item.SubItems[1].Text;
}
else
{
EmpIDtextBox.Text = string.Empty;
EmpNametextBox.Text = string.Empty;
}
}

// select row listview check in c#
foreach (ListViewItem itemRow in taskShowListView.Items)
{
if (itemRow.Items[0].Checked == true)
{
int taskId = Convert.ToInt32(itemRow.SubItems[0].Text);
string taskDate = itemRow.SubItems[1].ToString();
string taskDescription = itemRow.SubItems[2].ToString();
}
}

cannot set combo selected index when user type

I have a form with databound combobox, with dropstyle set as dropdown, so users could type in the combobox.
My problem is that when users type in the combobox and the value typed matches one of the values bound to the combobox it won't change the selectedindex, even though I've tried too. Instead, it sets the selected index to -1 (and thus the selected value is null).
Can anyone help? here's my code (one of my tries, i tried other approaches but none helped).
private void setCombo()
{
comboFromOther.DisplayMember = "tbl10_KupaID";
comboFromOther.ValueMember = "tbl10_KupaID";
comboFromOther.DataSource = dsKupotGemel.Tables[0];
}
private void comboToOther_TextChanged(object sender, EventArgs e)
{
comboDetail = changedComboText(2, comboToOther.Text);
textToOther.Text = comboDetail[0];
if (comboDetail[0] == "")
{
}
else
{
comboToOther.SelectedIndex = System.Int32.Parse(comboDetail[1]);
comboToOther.SelectedValue = System.Int32.Parse(comboDetail[2]);
}
}
private string[] changedComboText(int iComboType, string comboString)
{
if (groupCalculate.Visible == true)
{
groupCalculate.Visible = false;
}
string[] kupaDetail = new string[3];
kupaDetail[0] = "";
kupaDetail[1] = "";
kupaDetail[2] = "";
for (int i = 0; i <= dsKupotGemel.Tables[0].Rows.Count - 1; i++)
{
if (comboString == dsKupotGemel.Tables[0].Rows[i][0].ToString())
{
kupaDetail[0] = dsKupotGemel.Tables[0].Rows[i][1].ToString();
kupaDetail[1] = i.ToString();
kupaDetail[2] = comboString;
break;
}
else
{
}
}
return kupaDetail;
}

Maybe there is an error in your code?
Here is a working sample:
// Fields
private const string NameColumn = "Name";
private const string IdColumn = "ID";
private DataTable table;
Next, initialization
// Data source
table = new DataTable("SomeTable");
table.Columns.Add(NameColumn, typeof(string));
table.Columns.Add(IdColumn, typeof(int));
table.Rows.Add("First", 1);
table.Rows.Add("Second", 2);
table.Rows.Add("Third", 3);
table.Rows.Add("Last", 4);
// Combo box:
this.comboBox1.DisplayMember = NameColumn;
this.comboBox1.ValueMember = IdColumn;
this.comboBox1.DataSource = table;
this.comboBox1.DropDownStyle = ComboBoxStyle.DropDown;
this.comboBox1.TextChanged += comboBox1_TextChanged;
this.comboBox1.SelectedIndexChanged += this.comboBox1_SelectedIndexChanged;
Event handlers - TextChanged:
private void comboBox1_TextChanged(object sender, EventArgs e)
{
for (int i = 0; i < table.Rows.Count; i++)
{
if (table.Rows[i][NameColumn].ToString() == this.comboBox1.Text)
{
this.comboBox1.SelectedValue = table.Rows[i][IdColumn];
break;
}
}
}
Event handlers - SelectedIndexChanged:
private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
{
// Do here what is required
}
With this code, as soon as user types full name of item into combo box, SelectedIndexChanged is invoked through TextChanged.
There is also such thing as AutoCompleteMode, AutoCompleteSource. Don't know where they fit into your application.

BackgroundWorker for implementing "Search as you type" Combobox

I have created a code for my combobox, that can search addresses in a very large table on Sql Server with the help of stored procedure (i'm working with Entity framework). My stored procedure returns 10 hits and my code fills the combobox with search results. For doing this I'm using BackgroundWorker.
But here I'm now having big problems:
- although the combobox is filled with my search results, it always has the first item selected. Even if I type in only a letter, the whole text gets selected;
After that searching for the address doesn't work anymore. It searches only among these 10 results and I'm having no idea how to solve this. Here is my whole code, that causes me problems:
public String searchedItem = "";
public delegate void DelegateUpdateComboboxSelection(ComboBox myCombo,string value,int count);
BackgroundWorker m_bgworker = new BackgroundWorker();
static AutoResetEvent resetWorker = new AutoResetEvent(false);
m_bgworker.WorkerSupportsCancellation = true;
m_bgworker.DoWork += new DoWorkEventHandler(FillComboboxBindingList);
m_bgworker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(m_bgworker_RunWorkerCompleted);
BindingList<spIskalnikNaslovi_Result1> m_addresses = new BindingList<SP_Result1>();
void m_bgworker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
int count = (int)((object[])e.Result)[0];
string value = (string)((object[])e.Result)[1];
ComboBox myCombo = (ComboBox)((object[])e.Result)[2];
DelegateUpdateComboboxSelection ndelegate = new DelegateUpdateComboboxSelection(UpdateComboSelection);
if (this.InvokeRequired)
{
Invoke(ndelegate, new object[] {myCombo, value, count});
return;
}
else
{
UpdateComboSelection(myCombo, value, count);
return;
}
}
private void UpdateComboSelection(ComboBox myCombo, String value, int count)
{
myCombo = comboBox9;
myCombo.DataSource = m_addresses;
searchedItem = myCombo.Text;
if (count > 0)
{
myCombo.SelectionStart = value.Length;
myCombo.SelectionLength = searchedItem.Length - value.Length;
myCombo.DroppedDown = true;
}
else
{
myCombo.DroppedDown = false;
myCombo.SelectionStart = value.Length;
}
}
public void FillComboboxBindingList(object sender, DoWorkEventArgs e)
{
if (m_bgworker.CancellationPending)
{
resetWorker.Set();
e.Cancel = true;
return;
}
else
{
string value = (String)((Object[])e.Argument)[0];
List<SP_Result1> result;
result = _vsebina.SP_searcher(value).ToList<SP_Result1>();
m_addresses = new BindingList<SP_Result1>();
foreach (SP_Result1 rez in result)
{
if (m_addresses.Contains(rez))
{
continue;
}
else
{
m_addresses.Add(rez);
}
}
foreach (SP_Result1 r in m_addresses.ToArray())
{
if (!result.Contains(r))
{
m_addresses.Remove(r);
}
}
e.Result = new object[] { rezultat.Count, vrednost, null };
return;
}
}
private void comboBox9_KeyUp(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Back)
{
int searchStart = comboBox9.SelectionStart;
if (searchStart > 0)
{
searchStart--;
if (searchStart == 0)
{
comboBox9.Text = "";
}
else
{
comboBox9.Text = comboBox9.Text.Substring(0, searchStart + 1);
}
}
else
{
searchStart = 0;
}
e.Handled = true;
}
}
private void comboBox9_Enter(object sender, EventArgs e)
{
comboBox9.SelectionStart = 0;
comboBox9.SelectionLength = 0;
}
private void comboBox9_Click(object sender, EventArgs e)
{
comboBox9.Text = "";
}
private void comboBox9_KeyPress(object sender, KeyPressEventArgs e)
{
Search();
}
public void Search()
{
if (comboBox9.Text.Length < 4)
{
return;
}
else
{
if (m_bgworker.IsBusy)
{
m_bgworker.CancelAsync();
m_bgworker = new BackgroundWorker();
m_bgworker.WorkerSupportsCancellation = true;
m_bgworker.DoWork += new DoWorkEventHandler(FillComboboxBindingList);
m_bgworker.RunWorkerCompleted += new RunWorkerCompletedEventHandler(m_bgworker_RunWorkerCompleted);
}
m_bgworker.RunWorkerAsync(new object[] { comboBox9.Text, comboBox9 });
}
}
Maybe can someone enlighten me, what I'm doing wrong. This is first time, that I'm using BackgroundWorker. I have no idea, how
to achieve "search as you type" with combobox in any other way, because my datatable with addresses is quite large (million records).
Thanks in advance for any kind of help or code example.
Vladimir
Edit 1:
Ok, here is my code, before I have used BackGroundWorker. It worked, but it searches very very slow (it can take up to 10 seconds):
private void comboBox9_TextChanged(object sender, EventArgs e)
{
if (comboBox9.Text.Length < 4)
{
return;
}
else
{
FillCombobox(comboBox9.Text, comboBox9);
}
}
public void FillCombobox(string value, ComboBox myCombo)
{
List<spIskalnikNaslovi_Result1> result;
result = _vsebina.spIskalnikNaslovi1(value).ToList();
if (result.Count() > 0)
{
myCombo.DataSource = result;
myCombo.ValueMember = "HS_MID";
myCombo.DisplayMember = "NASLOV1";
var searchedItem = myCombo.Items[0].ToString();
myCombo.SelectionStart = value.Length;
myCombo.SelectionLength = searchedItem.Length - value.Length;
myCombo.DroppedDown = true;
}
else
{
myCombo.DroppedDown = false;
myCombo.SelectionStart = value.Length;
}
return;
}
Is there a way to speed this up without having backgroundworker?

make a button you will call searchbutton
and in click_event of this button call your search() method that run your backgroundworker
that fill the combobox
clear you key_press event of your combobox and it will work
the mistake is you key_press event that call every key stroke happening your search method
so retrieve it

You should get your items in a list, use that list to populate your combobox.
then set AutoCompleteMode property value to Suggest or Append or SuggestAppend and set AutoCompleteSoucre property value to ListItems.

For "Search as you Type", which is actually "Filter as you Type" more than search, you need to implement the OnKeyDown or KeyPressed event.
What you would do is take the search string, which is the current text at the time of the event, then filter the master list using that string. Normally one would use "Starts With" for the filtering, but you could also simply use "Contains". Then you live update the contents of the box with the results from the filter. This is accomplished by changing and refreshing the Datasource.

Here is my final solution without BackGroundWorker. It works quick with my large table, and is upgraded for using a stored procedure on SQL Server (if you use Entity Framework). I use Timer to make sure the user can find a value, that he is searching.
Here you can see the original solution, that I found on this site (thanks to Max Lambertini and algreat for the idea and working concept):
C# winforms combobox dynamic autocomplete
My solution:
private bool _canUpdate = true;
private bool _needUpdate = false;
List<spIskalnikNaslovi_Result1> dataFound;
private void comboBox12_TextChanged(object sender, EventArgs e)
{
if (_needUpdate)
{
if (_canUpdate)
{
_canUpdate = false;
refreshData();
}
else
{
restartTimer();
}
}
}
private void comboBox12_KeyUp(object sender, KeyEventArgs e)
{
if (e.KeyCode == Keys.Back)
{
int searchStart = comboBox12.SelectionStart;
if (searchStart > 0)
{
searchStart--;
if (searchStart == 0)
{
comboBox12.Text = "";
}
else
{
comboBox12.Text = comboBox12.Text.Substring(0, searchStart + 1);
}
}
else
{
searchStart = 0;
}
e.Handled = true;
}
}
private void comboBox12_TextUpdate(object sender, EventArgs e)
{
_needUpdate = true;
}
private void timer1_Tick(object sender, EventArgs e)
{
_canUpdate = true;
timer1.Stop();
refreshData();
}
private void refreshData()
{
if (comboBox12.Text.Length > 1)
{
FillCombobox(comboBox12.Text, comboBox12);
}
}
private void restartTimer()
{
timer1.Stop();
_canUpdate = false;
timer1.Start();
}
private void FillCombobox(string value, ComboBox myCombo)
{
dataFound = _vsebina.spIskalnikNaslovi1(value).ToList();
if (dataFound.Count() > 0)
{
myCombo.DataSource = dataFound;
myCombo.ValueMember = "HS_MID";
myCombo.DisplayMember = "NASLOV1";
var searchedItem = myCombo.Items[0].ToString();
myCombo.SelectionStart = value.Length;
myCombo.SelectionLength = searchedItem.Length - value.Length;
myCombo.DroppedDown = true;
return;
}
else
{
myCombo.DroppedDown = false;
myCombo.SelectionStart = value.Length;
return;
}
}

C# combobox options dependent on another combobox

I am working on a program in which a combobox's options are dependent on another combobox's selected option. The selected item from the first combobox chooses which options are in the second combobox. Does anyone know how to do this?
This is the button that adds the information to the first combobox
try
{
CustomerAccount aCustomerAccount = new CustomerAccount(txtAccountNumber.Text, txtCustomerName.Text,
txtCustomerAddress.Text, txtPhoneNumber.Text);
account.Add(aCustomerAccount);
cboClients.Items.Add(aCustomerAccount.GetCustomerName());
ClearText();
}
catch (Exception)
{
MessageBox.Show("Make sure every text box is filled in!", "Error", MessageBoxButtons.OK);
}
And here is the selectedIndex for the first combobox.
private void cboClients_SelectedIndexChanged(object sender, EventArgs e)
{
CustomerAccount custAccount = account[cboClients.SelectedIndex] as CustomerAccount;
if (custAccount != null)
{
txtAccountNumberTab2.Text = custAccount.GetAccountNumber();
txtCustomerNameTab2.Text = custAccount.GetCustomerName();
txtCustomerAddressTab2.Text = custAccount.GetCustomerAddress();
txtCustomerPhoneNumberTab2.Text = custAccount.GetCustomerPhoneNo();
}
}

Add a SelectedIndexChanged event handler for the first ComboBox. Use it to clear the content of the second ComboBox and populate it with the related items:
public Form1()
{
InitializeComponent();
for(int i = 0; i < 10; i++) {
comboBox1.Items.Add(String.Format("Item {0}", i.ToString()));
}
comboBox1.SelectedIndex = 0;
}
private void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
{
comboBox2.Items.Clear();
for (int i = 0; i < 5; i++)
{
comboBox2.Items.Add(String.Format("Item_{0}_{1}",
comboBox1.SelectedItem, i.ToString()));
}
comboBox2.SelectedIndex = 0;
}