Custom webpart properties not holding their values!

Question

I am dynamically adding items to a CheckBoxList that configures some settings in my web part. When I set the properties and click "OK" everything on my page works as expected and displays that data it should for the check boxes selected.

My problem is that if I leave the page and come back, it no longer has the values selected and my web part displays as if no check boxes are selected.

Below is the code I am using to create the custom web part property and save the values:

[ToolboxItemAttribute(false)]
public class MultiPart : WebPart
{
    // Visual Studio might automatically update this path when you change the Visual Web Part project item.
    private const string _ascxPath = @"~/_CONTROLTEMPLATES/MultiPart/MultiPart/MultiPartUserControl.ascx";
    public List<ListItem> SelectedTabs { get; set; }


    protected override void CreateChildControls()
    {
        MultiPartUserControl control = Page.LoadControl(_ascxPath) as MultiPartUserControl;
        if (control != null)
            control.myWebPart = this;
        Controls.Add(control);
    }

    public override EditorPartCollection CreateEditorParts()
    {
        ArrayList editorArray = new ArrayList();
        MyEditorPart edPart = new MyEditorPart();
        edPart.ID = this.ID + "_editorPart1";
        editorArray.Add(edPart);
        EditorPartCollection editorParts = new EditorPartCollection(editorArray);
        return editorParts;
    }

}

public class MyEditorPart : EditorPart
{
    private Label lbl_Options;
    private CheckBoxList cbl_WebParts;

    protected override void CreateChildControls()
    {
        base.CreateChildControls();
        cbl_WebParts = new CheckBoxList();
        lbl_Options = new Label();
        lbl_Options.Text = "<strong>Select which web parts to include:</strong><br />";

        string _ascxPath = @"~/_CONTROLTEMPLATES/MultiPart/MultiPart/MultiPartUserControl.ascx";
        Control ascxControl = Page.LoadControl(_ascxPath);

        foreach (Control c in ascxControl.FindControl("tabs").Controls)
        {
            if(c.GetType().Equals(typeof(HtmlGenericControl)) && ((HtmlGenericControl)c).TagName.ToLower() == "div")
            {
                cbl_WebParts.Items.Add(new ListItem(((HtmlGenericControl)c).Attributes["title"], c.ID));
            }
        }

        Controls.Add(lbl_Options);
        Controls.Add(cbl_WebParts);
    }

    public override bool ApplyChanges()
    {
        EnsureChildControls();
        MultiPart webPart = WebPartToEdit as MultiPart;
        if (webPart != null)
        {
            if (webPart.SelectedTabs == null)
            {
                webPart.SelectedTabs = new List<ListItem>();
            }

            foreach (ListItem li in cbl_WebParts.Items)
            {
                if (li.Selected)
                {
                    webPart.SelectedTabs.Add(li);
                }
            }
        }
        return true;
    }

    public override void SyncChanges()
    {
        EnsureChildControls();
        MultiPart webPart = WebPartToEdit as MultiPart;

        if (webPart != null && webPart.SelectedTabs != null)
        {
            foreach (ListItem li in webPart.SelectedTabs)
            {
                cbl_WebParts.Items.FindByValue(li.Value).Selected = true;
            }
        }
    }

Is there anything else I should be doing to get these values to persist across visits?

Answer 1

Your SelectedTabs property should be persisted. Try use this code:

[Personalizable(PersonalizationScope.Shared),
 WebBrowsable(false)]
public List<ListItem> SelectedTabs { get; set; }

Update:

Also, you should not store ListItem's. I changed List<ListItem> to List<string> and fixed some code, and it is working on my machine now. Here is the resulting code:

[ToolboxItemAttribute(false)]
public class VisualWebPart1 : WebPart
{
    // Visual Studio might automatically update this path when you change the Visual Web Part project item.
    private const string _ascxPath = @"~/_CONTROLTEMPLATES/MultiPart/MultiPart/MultiPartUserControl.ascx";

    [Personalizable(PersonalizationScope.Shared),
    WebBrowsable(false)]
    public List<string> SelectedTabs { get; set; }


    protected override void CreateChildControls()
    {
        Control control = Page.LoadControl(_ascxPath);
        Controls.Add(control);
    }

    public override EditorPartCollection CreateEditorParts()
    {
        ArrayList editorArray = new ArrayList();
        MyEditorPart edPart = new MyEditorPart();
        edPart.ID = this.ID + "_editorPart1";
        editorArray.Add(edPart);
        EditorPartCollection editorParts = new EditorPartCollection(editorArray);
        return editorParts;
    }

}

public class MyEditorPart : EditorPart
{

    private Label lbl_Options;
    private CheckBoxList cbl_WebParts;

    protected override void CreateChildControls()
    {
        base.CreateChildControls();
        cbl_WebParts = new CheckBoxList();
        lbl_Options = new Label();
        lbl_Options.Text = "<strong>Select which web parts to include:</strong><br />";

        string _ascxPath = @"~/_CONTROLTEMPLATES/MultiPart/MultiPart/MultiPartUserControl.ascx";
        Control ascxControl = Page.LoadControl(_ascxPath);

        foreach (Control c in ascxControl.FindControl("tabs").Controls)
        {
            if(c.GetType().Equals(typeof(HtmlGenericControl)) && ((HtmlGenericControl)c).TagName.ToLower() == "div")
            {
                cbl_WebParts.Items.Add(new ListItem(((HtmlGenericControl)c).Attributes["title"], c.ID));
            }
        }

        Controls.Add(lbl_Options);
        Controls.Add(cbl_WebParts);
    }

    public override bool ApplyChanges()
    {
        EnsureChildControls();
        VisualWebPart1 webPart = WebPartToEdit as VisualWebPart1;
        if (webPart != null)
        {
            if (webPart.SelectedTabs == null)
            {
                webPart.SelectedTabs = new List<string>();
            }

            foreach (ListItem li in cbl_WebParts.Items)
            {
                if (li.Selected)
                {
                    webPart.SelectedTabs.Add(li.Value);
                }
            }
        }
        return true;
    }

    public override void SyncChanges()
    {
        EnsureChildControls();
        VisualWebPart1 webPart = WebPartToEdit as VisualWebPart1;

        if (webPart != null && webPart.SelectedTabs != null)
        {
            foreach (string value in webPart.SelectedTabs)
            {
                cbl_WebParts.Items.FindByValue(value).Selected = true;
            }
        }
    }
}