I am setting up a ComboBox to use the AutoComplete feature with AutoCompleteMode = Append and AutoCompleteSource = ListItems. When I load my form the Item list of the ComboBox is empty, and then I keep adding new values from the ComboBox.Text on a specified event (when a specific button is pressed).
Bottom line is that when the ComboBox's Items property is populated dynamically from an event, the AutoCompletion does not work as expected. My first entry into ComboBox.Items, always completes properly, but the later ones don't. If I click the arrow to dropdown the list, then all the Items so far entered autocomplete properly. If I Alt-Tab into another application and come back to the combobox, all the Items entered so far autocomplete properly.
It comes across to me that internally the combobox reloads its autocomplete list based on some event, but so far I have tried calling
ResumeLayout(true);
Refresh();
Invalidate(true);
Update();
DroppedDown = true;
DroppedDown = false;
but to no avail
Can someone enlighten me on how to dynamically add entries in the ComboBox.Items list and still have auto-complete with ComboBox.AutoCompleteSource = ListItems work correctly.
btnExecute is the default button on the form which contains the combobox. So the below function is invoked on pressing enter on the combobox
private void btnExecute_Click( object sender, EventArgs e ) {
cboCommand.SuspendLayout();
cboCommand.Items.Add(cboCommand.Text);
cboCommand.Text = "";
// Make some call here, so combobox reloads its cache for autocompletion
}
relevant portion from the auto generated winforms code
this.cboCommand.AutoCompleteMode = System.Windows.Forms.AutoCompleteMode.Append;
this.cboCommand.AutoCompleteSource = System.Windows.Forms.AutoCompleteSource.ListItems;
this.cboCommand.FormattingEnabled = true;
I am using .NET4 Client profile on Windows Vista. May be it plays a role here
Anyone?
Related
I created a project that collects Personal Informations. I added a combobox to get title of Personal. Combobx items which is in ENUM, added at load. I save informations at listview, everythings Runs Perfectly i have double click event for listview. It returns all information to the their first position like Textboxes. But Combobox doesnt get its value to back. Can you show me how i can do ?
Enums Added ComboBox
cbUnvan.Items.AddRange(Enum.GetNames(typeof(Unvan)));
if Combobox item (which is Enum) selected, goes to personel.Unvan Property. (Personel is Class)
personel.Unvan = (Unvan)Enum.Parse(typeof(Unvan), cbUnvan.SelectedItem.ToString());
When i double click to listview item informations goes to their places. example is at below
txtTC.Text = lvTablo.SelectedItems[0].SubItems[0].Text;
dtpIseGirisTarihi.Value = Convert.ToDateTime(lvTablo.SelectedItems[0].SubItems[3].Text);
MY PROBLEM IS HERE -- But Combobox doesnt do same action with this code below
cbUnvan.SelectedItem = (Unvan)Enum.Parse(typeof(Unvan), lvTablo.SelectedItems[0].SubItems[8].Text);
I have a simple combobox in c# forms which is populated from an array.
I have set AutoCompleteMode to SuggestAppend and AutoCompleteSource to ListItems. This allows me to filter through the list quickly by typing a string into the combobox and matching items are displayed as I type along. This works great.
However, when the drop down list is open and I start typing, the filtered list appears on top of the dropdown list but I cannot select from the filtered list but only from the drop down.
How to disable drop down list while open as soon as user enters a character into the combobox.
Currently only have one method for the combobox
private void SelectJobDropdown_SelectedIndexChanged(object sender, EventArgs e)
{
//plenty of code here
}
I have tried adding other methods for the combobox such as KeyPress or Keydown but none seems to be working for as I'm very likely doing something wrong
Using Visual Studio 2015
If I understood you correctly you don't like the overlapping list over the old drop down. Since you type letters into the ComboBox I would suggest to use the comboBox1_TextUpdate event. This nice line of code should fix your problem:
private void comboBox1_TextUpdate(object sender, EventArgs e)
{
comboBox1.DropDownStyle = ComboBoxStyle.Simple;
Setting the ComboBox.DropDownStyle property, which
specifies whether the list is always displayed or whether the list is displayed in a drop-down[...]
to ComboBoxStyle.Simple, which
Specifies that the list is always visible and that the text portion is editable. This means that the user can enter a new value and is not limited to selecting an existing value in the list.
will remove the original dropdown (long list) and only the filtered results remain.
Uses: VS 2012;
I've a combobox attached to a datasource in my form. And things work fine. When I run the form, again everything works fine; I can select an item in the dropdown list and it updates to the datasource as well. My problem comes when I need to deselect/revert what I have selected after I saved or Remove what I have select (basically should go as null for that field value).
Our legacy system was built in Delphi 3 & 5, and users got a feature of right-clicking on the dropdown list and get a small popup like button named
Blank
which blanks what have been selected. I could not find anything that will do the same what ever user have selected in .NET's combo box.
You can add a new item in dropdown named -Select-( or something similar name) by using following code:
drp.DataSource = dataSet;
drp.DataBind();
// do it after binding
drp.Items.Insert(0, new ListItem("-Select-", "NA"));
If you are binding in xaml then on page_load event you can write only this line
drp.Items.Insert(0, new ListItem("-Select-", "NA"));
Now if user want to deselect choice, he/she will simply select -Select- item.
Whilst thanking all of your Answers and suggestions, I used #V4Vendetta's idea and composed my solution.
Similarly to deleting a record in a datagridview where you click Delete key, I took the same concept and associated my solution with Delete Key.
What I did was created a handler for ComboBox's Keypress Event like:
private void comboBox_KeyPress(object sender, System.Windows.Forms.KeyEventArgs e)
{
if (e.KeyCode == Keys.Delete)
{
(sender as ComboBox).SelectedIndex = -1;
}
}
And linked to every ComboBox's available
ComboBox1.KeyDown += new KeyEventHandler(comboBox_KeyPress);
ComboBox2.KeyDown += new KeyEventHandler(comboBox_KeyPress);
Now when user clicks Delete key while the ComboBox selected/active, it gets blank.
I have a listbox in my winform, when an item in the listbox is selected, a value is placed into a textbox in the same Form. There my many items in my listbox which when selected, i want the text box to be empty so i can pass in the new value. How do i check is if the user has clicked on something other their initial selected item? i get the currently selected item like this below:
var selectedItem = (ReportItems)listbox.selectedItem
You can use the SelectedIndexChanged event on your ListBox . You can create an event handler for this event to determine when the selected index in the ListBox has been changed. This can be useful when you need to display information in other controls based on the current selection in the ListBox. You can use the event handler for this event to load the information in the other controls.
See MSDN documentation: link
You can add a global variable for your ReportItems and call it 'selItem'.
After the user changed the selected Item you check the "new" selectedItem with the 'selItem'-variable.. i don't think that a listbox has a method that can check if the selection has changed from the previous one..
I'm not sure if there is a reason you're not leveraging the SelectionChanged event of the ListBox or not but you should be if you're not. Further, determining if it's different than the initially selected item should be pretty straight forward because you can save the initially selected item in a private variable in your form and compare every time the method handler for SelectionChanged fires.
Other than this, there's not much more I can suggest because your questions isn't terribly clear and there is no code to look at.
My solution was to always clear the textbox first. So as soon as a user selects an item in the listview, rather than populating the textbox straight away, clear the textbox before populating it.
clearText(); is called soon as a listbox item is clicked.
public void clearText()
{
textBox1.Clear();
textBox2.Clear();
textBox3.Clear();
textBox4.Clear();
textBox5.Clear();
textBox6.Clear();
textBox7.Clear();
textBox8.Clear();
textBox9.Clear();
textBox10.Clear();
textBox11.Clear();
textBox12.Clear();
}
I want to select all the items in listbox. Here iam using listbox1.selectAll() for selecting all items. And for Deselecting all items in a listbox iam using listbox1.selecteditems.clear(). thats working perfectly
Now i want to do validations like if i select all items by using listbox1.selectAll() and then if i select one item in listbox all selected items selection is going off and the radio button still showing the selectall is checked.But i dont have all items selected in a listbox. How to do that. Any suggestion plz.
I would suggest using a single CheckBox or two standard Buttons instead of RadioButtons.
If some but not all or none of the items are selected, which RadioButton will you check? It doesn't make sense to have a "Some selected" RadioButton.
With buttons, you simply select/unselect all of the items when the button is pressed.
With a single CheckBox, you can use the three state feature to set the CheckBox as follows: checked = all selected; third state = some selected; unchecked = none selected.
Handle the appropriate Checked and Unchecked handlers on the CheckBox for updating the ListBox, and respond to the ListBox.SelectionChanged event to update the CheckBox in response to manual selection changes.
You could implement a check in the ListBox1_SelectedIndexChanged event to do a check against the checkbox i.e.
private void listBox1_SelectedIndexChanged(object sender, EventArgs e)
{
myCheckBox.Checked = listBox1.SelectedItems.Count > 1;
}