topic Re: Adding items to combobox list using a dictionary in ArcGIS Pro SDK Questions

Adding items to combobox list using a dictionary

mstranovsky — Thu, 03 Apr 2025 12:16:03 GMT

I have a dictionary of values named "odDict". When i use the following code it only adds the first value in the dictionary. How can i get it to populate the list using all values in the dictionary?

foreach (KeyValuePair<string, string> kvp in odDict)
{
string key = kvp.Key;
string val = kvp.Value;
cmbOverlayDistrict.Items.Add(val);
}

Re: Adding items to combobox list using a dictionary

RadekMandovec — Thu, 03 Apr 2025 12:31:51 GMT

You can use:

List<object> values = odDict.Values.ToList(); cmbOverlayDistrict.Items.AddRange(items: values.ToArray());

Re: Adding items to combobox list using a dictionary

mstranovsky — Thu, 03 Apr 2025 13:52:00 GMT

Thank you for the reply but when using your code I now see this:

Re: Adding items to combobox list using a dictionary

RadekMandovec — Fri, 04 Apr 2025 04:21:13 GMT

And if you use this?

List<object> values= new(odDict.Values);

Re: Adding items to combobox list using a dictionary

SumitMishra_016 — Thu, 10 Apr 2025 11:09:52 GMT

I have put my sample code, it is working for me

public ObservableCollection<string> CaseNumbers { get; set; } = new(); // Temporary list to avoid multiple UI updates List<string> caseNumbersList = new(); while (await reader.ReadAsync()) { string caseNo = reader.GetString(0); caseNumbersList.Add(caseNo); } // Update UI on the main thread System.Windows.Application.Current.Dispatcher.Invoke(() => { CaseNumbers.Clear(); foreach (var caseNo in caseNumbersList) { CaseNumbers.Add(caseNo); } // Select the latest case number CaseNumberComboBox.SelectedItem = CaseNumbers.FirstOrDefault(); });

Re: Adding items to combobox list using a dictionary

Wolf — Tue, 15 Apr 2025 16:11:13 GMT

@mstranovsky Your code snippet is not applicable in an ArcGIS Pro Add-in. There are two patterns in ArcGIS Pro to deploy a ComboBox:

1) If you are using a Pro Combo box ribbon control you would load the 'Ribbon' Dropdown from a dictionary like this:

internal class TestComboBox : ComboBox { private bool _isInitialized; /// <summary> /// Combo Box constructor /// </summary> public TestComboBox() { UpdateCombo(); } // create a dictionary with an entry for each US state, the value should be the capital city of that state private Dictionary<string, string> _stateCapitals = new Dictionary<string, string> { { "Alabama", "Montgomery" }, { "Alaska", "Juneau" }, { "Arizona", "Phoenix" }, { "Arkansas", "Little Rock" }, { "California", "Sacramento" }, { "Colorado", "Denver" }, { "Connecticut", "Hartford" }, { "Delaware", "Dover" }, { "Florida", "Tallahassee" }, { "Georgia", "Atlanta" } }; /// <summary> /// Updates the combo box with all the capitals of the US states /// </summary> private void UpdateCombo() { if (_isInitialized) SelectedItem = ItemCollection.FirstOrDefault(); if (!_isInitialized) { // Updates the combo box with all the capital names of the US states foreach (var capital in _stateCapitals.Values) { Add(new ComboBoxItem(capital)); } _isInitialized = true; } Enabled = true; SelectedItem = ItemCollection.FirstOrDefault(); } /// <summary> /// The on comboBox selection change event. /// </summary> /// <param name="item">The newly selected combo box item</param> protected override void OnSelectionChange(ComboBoxItem item) { if (item == null) return; if (string.IsNullOrEmpty(item.Text)) return; } }

2. If you are using a combobox on a Dockpane, you should use the MVVM pattern to populate the combobox content. In this case, please model your code after @SumitMishra_016 's sample snippet.

Re: Adding items to combobox list using a dictionary

Wolf — Wed, 23 Apr 2025 17:20:24 GMT

I attached a small sample add-in project that has a Combo dropdown on the ArcGIS Pro ribbon and two dropdowns on a Dockpane. I am using a dictionary (keys and values) to 'feed' the dropdown content.