SfDataform crashed on binding

[Tung]

Hello,

I discovered very weird behaviour of the DataForm. I could not understand the reason why it crash every time we use two DataFormTextItem on the XAML.

If we use only one editor from two. It works. 

If we let the form to auto generate Text editors, it works too.

I have a very basic setup to display a DataObject to the DataForm:

1. Data object Code:
   

 public class Foo

    {

        public Foo()

        {

            EmpName = "Foo Name";

            DOB = "2019-02-26";

        }

        public string EmpName { get; set; }

        public string DOB { get; set; }

    }

2. Form XAML:

<?xml version="1.0" encoding="utf-8"?>

<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"

             xmlns:sf ="clr-namespace:Syncfusion.XForms.DataForm;assembly=Syncfusion.SfDataForm.XForms"

             xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"

             xmlns:d="http://xamarin.com/schemas/2014/forms/design"

             xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d" x:Class="DateCustomEditor.MainPage">

    <ContentPage.Content>

    <sf:SfDataForm x:Name="dataform" AutoGenerateItems="False" Margin="0,60,0,20">

        <sf:SfDataForm.Items>

            <sf:DataFormTextItem Name="EmpName" Editor="Text" ></sf:DataFormTextItem>

          

            <sf:DataFormTextItem Name="DOB" Editor="Text" ></sf:DataFormTextItem>

             <!--Uncomment one of two DataFormItem make the form works.--> 

        </sf:SfDataForm.Items>

    </sf:SfDataForm>

    </ContentPage.Content>

</ContentPage>

3. XAML binding 

 protected override void OnAppearing()

        {

            base.OnAppearing();

 

            var _foo = new Foo();                

            dataform.DataObject = _foo;

            

        }

Exception:

System.NullReferenceException: Object reference not set to an instance of an object

  at Syncfusion.iOS.DataForm.Editors.DataFormEditor`1[EditorView].UnWireEvents (Syncfusion.iOS.DataForm.DataFormItem dataFormItem, UIKit.UIView view) [0x00036] in <0918c5f150ff479494d5d783bad15235>:0

  at Syncfusion.iOS.DataForm.DataFormItemView.Dispose (System.Boolean isDisposing) [0x0003d] in <0918c5f150ff479494d5d783bad15235>:0

  at Foundation.NSObject.Dispose () [0x00000] in /Library/Frameworks/Xamarin.iOS.framework/Versions/13.6.0.12/src/Xamarin.iOS/Foundation/NSObject2.cs:147

  at Syncfusion.iOS.DataForm.ScrollPanel.RemoveChildViews () [0x00072] in <0918c5f150ff479494d5d783bad15235>:0

  at Syncfusion.iOS.DataForm.ScrollPanel.OnDataObjectChanged () [0x00000] in <0918c5f150ff479494d5d783bad15235>:0

  at Syncfusion.iOS.DataForm.SfDataForm.OnDataObjectChanged (System.Object oldValue, System.Object newValue) [0x00029] in <0918c5f150ff479494d5d783bad15235>:0

  at Syncfusion.iOS.DataForm.SfDataForm.set_DataObject (System.Object value) [0x00017] in <0918c5f150ff479494d5d783bad15235>:0

  at Syncfusion.XForms.iOS.DataForm.SfDataFormMapping.SetDataFormProperties (System.String propertyName, Syncfusion.iOS.DataForm.SfDataForm nativeDataForm, Syncfusion.XForms.DataForm.SfDataForm dataForm) [0x00014] in <0918c5f150ff479494d5d783bad15235>:0

  at Syncfusion.XForms.iOS.DataForm.SfDataFormViewRenderer.OnDataFormPropertyChanged (System.Object sender, System.ComponentModel.PropertyChangedEventArgs e) [0x00022] in <0918c5f150ff479494d5d783bad15235>:0

  at at (wrapper delegate-invoke) <Module>.invoke_void_object_PropertyChangedEventArgs(object,System.ComponentModel.PropertyChangedEventArgs)

  at Xamarin.Forms.BindableObject.OnPropertyChanged (System.String propertyName) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:211

  at Xamarin.Forms.Element.OnPropertyChanged (System.String propertyName) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\Element.cs:359

  at Xamarin.Forms.BindableObject.SetValueActual (Xamarin.Forms.BindableProperty property, Xamarin.Forms.BindableObject+BindablePropertyContext context, System.Object value, System.Boolean currentlyApplying, Xamarin.Forms.Internals.SetValueFlags attributes, System.Boolean silent) [0x00114] in D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:443

  at Xamarin.Forms.BindableObject.SetValueCore (Xamarin.Forms.BindableProperty property, System.Object value, Xamarin.Forms.Internals.SetValueFlags attributes, Xamarin.Forms.BindableObject+SetValuePrivateFlags privateAttributes) [0x00173] in D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:379

  at Xamarin.Forms.BindableObject.SetValue (Xamarin.Forms.BindableProperty property, System.Object value, System.Boolean fromStyle, System.Boolean checkAccess) [0x00042] in D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:316

  at Xamarin.Forms.BindableObject.SetValue (Xamarin.Forms.BindableProperty property, System.Object value) [0x00000] in D:\a\1\s\Xamarin.Forms.Core\BindableObject.cs:293

  at Syncfusion.XForms.DataForm.SfDataForm.set_DataObject (System.Object value) [0x00000] in <53a79c3ef26e487ea76e53887222bc24>:0

  at DateCustomEditor.MainPage.OnAppearing () [0x0000e] in /Users/tung/Projects/DateCustomEditor/DateCustomEditor/MainPage.xaml.cs:27

  at Xamarin.Forms.Page.SendAppearing () [0x00024] in D:\a\1\s\Xamarin.Forms.Core\Page.cs:364

  at Xamarin.Forms.Platform.iOS.PageRenderer.ViewDidAppear (System.Boolean animated) [0x0004b] in <f0489d3941b24a20a5b9223b572ec7c0>:0

  at at (wrapper managed-to-native) UIKit.UIApplication.UIApplicationMain(int,string[],intptr,intptr)

  at UIKit.UIApplication.Main (System.String[] args, System.IntPtr principal, System.IntPtr delegate) [0x00005] in /Library/Frameworks/Xamarin.iOS.framework/Versions/13.6.0.12/src/Xamarin.iOS/UIKit/UIApplication.cs:86

  at UIKit.UIApplication.Main (System.String[] args, System.String principalClassName, System.String delegateClassName) [0x0000e] in /Library/Frameworks/Xamarin.iOS.framework/Versions/13.6.0.12/src/Xamarin.iOS/UIKit/UIApplication.cs:65

  at DateCustomEditor.iOS.Application.Main (System.String[] args) [0x00001] in /Users/tung/Projects/DateCustomEditor/DateCustomEditor.iOS/Main.cs:17

[Ajith Kumar Senthil Kumar]

Hi Tung, 

 

Thank you for contacting Syncfusion support. 

 

Currently, we are analyzing your reported issue of “Getting null reference while using two DataFormTextItem on the XAML.” In Xamarin.Forms. We will validate and update you the further details in two business days (November 11, 2019). We appreciate your patience until then. 

 

Regards,
Ajith 

[Ajith Kumar Senthil Kumar]

Hi Tung,      

    

Thanks for your patience.    

    

We have already found and fixed the issue “Getting null reference while using two DataFormTextItem on the XAML” and included the issue fix in our upcoming Weekly nuget, which is expected to publish on 12 November 2019. We appreciate your patience until then.    

    

Regards,    

Ajith    

[Ajith Kumar Senthil Kumar]

Hi Tung,                    

      

We have fixed the reported issue “Getting null reference while using two DataFormTextItem on the XAML” and included the issue fix in our latest Weekly NuGet release update version 17.3.0.27 which is available for download (nuget.org).

 

We thank you for your support and appreciate your patience in waiting for this update. Please get in touch with us if you would require any further assistance. 

 

Regards,
Ajith