Problem to synchronise two DataContext bound ComboBoxes
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Hi, I’m trying to do something quite simple, I believe, but am very new to WPF and can’t figure it out. I want to display bank account details of a specific employee (which I select separately), and I want to let the user change those details if needed. My problem concerns specifically the following 3 tables: Banks: - BankID (PK) - CountryID - BankName - ... Countries: - CountryID (PK) - CountryName - ... BankAccounts: - BankAccountID (PK) - BankID - ... On my application’s MainWindow I have 2 ComboBoxes. I want to load the first one (cmbBankCountry) with a list of all the countries from ‘Countries’ table, and then automatically select the country which corresponds to the employee’s bank account. Similarly, I want the second ComboBox (cmbBanks) to be loaded with the names of all the banks that are associated with the selected country, and here too, select automatically the bank associated with that employee’s bank account. Of course, if the user changes the selection of the country for that bank account, the second ComboBox should be reloaded and display only the banks associated with the newly selected country. All the data comes from an SQL database via Linq-To-SQL classes (dbml), which I generated to represent the database tables. I.e. I have a Bank class, a Country class, a BankAccount class, etc. defined in a DataContext that I declared as a Private Shared variable of Application. I also created a ReadOnly property called DBMain to access it. So far I tried to tackle this task as follows: To load the first Combobox with all the countries I placed the following code in the MainWindow_Loaded event:
Dim lstCountries As List(Of Country) = Application.DBMain.GetCountries()
cmbBankCountry.ItemsSource = lstCountries
cmbBankCountry.DisplayMemberPath = "CountryName"
cmbBankCountry.SelectedValuePath = "CountryID"The GetCountries function looks like this:
Public Function GetCountries() As List(Of Country)
Dim lstCountry As List(Of Country) = (From c In Application.DBMain.Countries Select c ).ToList Return lstCountryEnd Function
To load the second Combobox with the corresponding banks, I created an event that is triggered when the first Combobox’s selection (country) is changed:
Private Sub DisplayBanksForCountry()
Dim lstBanks As -
Hi, I’m trying to do something quite simple, I believe, but am very new to WPF and can’t figure it out. I want to display bank account details of a specific employee (which I select separately), and I want to let the user change those details if needed. My problem concerns specifically the following 3 tables: Banks: - BankID (PK) - CountryID - BankName - ... Countries: - CountryID (PK) - CountryName - ... BankAccounts: - BankAccountID (PK) - BankID - ... On my application’s MainWindow I have 2 ComboBoxes. I want to load the first one (cmbBankCountry) with a list of all the countries from ‘Countries’ table, and then automatically select the country which corresponds to the employee’s bank account. Similarly, I want the second ComboBox (cmbBanks) to be loaded with the names of all the banks that are associated with the selected country, and here too, select automatically the bank associated with that employee’s bank account. Of course, if the user changes the selection of the country for that bank account, the second ComboBox should be reloaded and display only the banks associated with the newly selected country. All the data comes from an SQL database via Linq-To-SQL classes (dbml), which I generated to represent the database tables. I.e. I have a Bank class, a Country class, a BankAccount class, etc. defined in a DataContext that I declared as a Private Shared variable of Application. I also created a ReadOnly property called DBMain to access it. So far I tried to tackle this task as follows: To load the first Combobox with all the countries I placed the following code in the MainWindow_Loaded event:
Dim lstCountries As List(Of Country) = Application.DBMain.GetCountries()
cmbBankCountry.ItemsSource = lstCountries
cmbBankCountry.DisplayMemberPath = "CountryName"
cmbBankCountry.SelectedValuePath = "CountryID"The GetCountries function looks like this:
Public Function GetCountries() As List(Of Country)
Dim lstCountry As List(Of Country) = (From c In Application.DBMain.Countries Select c ).ToList Return lstCountryEnd Function
To load the second Combobox with the corresponding banks, I created an event that is triggered when the first Combobox’s selection (country) is changed:
Private Sub DisplayBanksForCountry()
Dim lstBanks As -
Check out this link on "WPF parent-child combo boxes": http://stackoverflow.com/questions/2882006/wpf-binding-comboboxes-to-parent-child-model[^]