Question

I have a listview with two columns Devicename and DeviceAddress. I have maintained an observablecollection for the listview. I am using MVVM pattern.

View:

<ListView Height="100" ItemsSource="{Binding I2CDeviceList}" SelectedItem="{Binding SelectedI2CAddress, Mode=TwoWay}" Name="I2cDeviceList">
                <ListView.View>
                    <GridView>
                        <GridViewColumn Header="I2C Device" Width="190" DisplayMemberBinding="{Binding I2CDevName}" />
                        <GridViewColumn Header="I2C Device Address" Width="203" DisplayMemberBinding="{Binding I2CDeviceAddress}" />
                    </GridView>
                </ListView.View>
</ListView>

Both I2CDevicename and I2CDeviceAddress are part of my model class.

ViewModel:

public ObservableCollection<ModelClass> I2CDeviceList
    {
        get { return _I2CDeviceList; }
        set
        {
            _I2CDeviceList = value;
            NotifyPropertyChanged("I2CDeviceList");
        }
    }

The items to be added inside DeviceName & DeviceAddress respectively are:

{ T("Other"), T("0x00")},
{ T("TI Codec(TLV320AIC3104)"), T("0x18")},
{ T("Chip ID GPIO(PCA9500)"),T("0x20")},
{ T("GPIO - power rail control(PCA9555DB)"),T("0x24")},
{ T("Digital Potentiometer(AD5252)"),T("0x2C")},
{ T("Audience chip(eSxxx)"),T("0x3E")},
{ T("Spartan 3A FPGA(XC3SD3400A)"),T("0x40")},.......

Now In a constructor of the viewmodel class, I can add the items inside obs.Coll as follows:

public ObservableCollection<ModelClass> _I2CDeviceList = new ObservableCollection<ModelClass>()
        {                
            new ModelClass() {I2CDevName = "Other", I2CDeviceAddress= "0x00"},
            new ModelClass() {I2CDevName = "TI Codec", I2CDeviceAddress = "0x18"},  .........             
        };

but its a tedious job to add 15 items and I end up having 15 items statements. Is their a way i can add the items using a single loop to avoid many statements?

Answer 1

So either you make a constructor to the ModelClass which makes it easier for you to create, and at the same time fill in the values.

public class ModelClass
{
    public string I2CDevName { get; set; }
    public string I2CDeviceAddress { get; set; }

    public ModelClass(string DeviceName, string DeviceAddress)
    {
        this.I2CDevName = DeviceName;
        this.I2CDeviceAddress = DeviceAddress;
    }
}

This would reduce the code somewhat but there still will be some typing:

public ObservableCollection<ModelClass> _I2CDeviceList = new ObservableCollection<ModelClass>()
{                
    new ModelClass("Other","0x00"),
    new ModelClass("TI Codec", "0x18"), .......
};

Or you can make a “factory”, a static function in the ModelClass that takes a whole list and returns a whole ObservableCollection

So you will have to change some in the list that you have, but if you change that to something like (maybe someone can come up with a better idea to use the list better, but:

List<string[]> list = new List<string[]>() { new string[] {"Other", "0x00"},
                                             new string[] {"Audience chip(eSxxx), "0x3E"}, ... };

And then add the static function to the ModelClass:

public class ModelClass
{
    public string I2CDevName { get; set; }
    public string I2CDeviceAddress { get; set; }

    public ModelClass(string DeviceName, string DeviceAddress)
    {
        this.I2CDevName = DeviceName;
        this.I2CDeviceAddress = DeviceAddress;
    }

    //Collection Factory
    public static ObservableCollection<ModelClass> CreateCollection(List<string[]> models)
    {
        ObservableCollection<ModelClass> tmpColl = new ObservableCollection<ModelClass>();
        foreach (string[] s in models)
        {
            tmpColl.Add(new ModelClass(s[0],s[1]));
        }
        return tmpColl;
    }
}

And then just run:

List<string[]> list = new List<string[]>() { new string[] {"Other",...},
                                                                      ...};
public ObservableCollection<ModelClass> _I2CDeviceList = ModelClass.CreateCollection(list);

Tada…