Getting null when IValueConverter???

Question

public object Convert(object value, Type targetType, object parameter, string language)
        {
            TextBlock txt = new TextBlock();
            string str = (string)value;
            string[] strList = str.Split('=>');

            Run run2 = new Run();
            SolidColorBrush mySolidColorBrush = new SolidColorBrush(Color.FromArgb(255,0,0,255));
            run2.Foreground = mySolidColorBrush;
            txt.Inlines.Add(run2);

            return txt;
        }

        public object ConvertBack(object value, Type targetType, object parameter, string language)
        {
            return false;
        }

if(i< orth.Count())
                                                        {
                                                            results.senselist += type_translation[i].InnerText.Trim() + "=>" + orth[i].InnerText.Trim() + " ";
                                                        }
                                                        else
                                                        {
                                                            results.senselist += type_translation[i].InnerText.Trim() + "|";
                                                        }

<TextBlock Text="{Binding senselist,Converter={StaticResource textconvert}}"></TextBlock>

On unversial app not suport <label> so I use Textblock. but 

string str = (string)value;
            string[] strList = str.Split('=>');

it is null.

Answer 1

If value is NULL in your Convert method, the binding to the senselist property has failed. Make sure that the DataContext of the TextBlock contains a public property named "senselist" and that this property actually returns a string value.

I also notice that you are trying to return a TextBlock from the converter but the Text property of a TextBlock cannot be set to another TextBlock.

You should awlays return a string from the converter. If you want to display the TextBlock in different colours you could bind the Text property of the Run element(s) and for example return a substring of the source string from the converter:

<TextBlock>
<Run Text="default colour..." />
<Run Text="{Binding senselist,Converter={StaticResource textconvert}}" Foreground="Green" />
</TextBlock>

 

Please remember to close your threads by marking helpful posts as answer and then start a new thread if you have a new question. Please don't post several questions in the same thread.

Answer 2

As results is "Windows.UI.Xaml.Controls.TextBlock". I had debugger then return txt is nullwhile "txt.Inlines.Add(run2);" is having data. Everyone help me to solve it.

Answer 3

public object Convert(object value, Type targetType, object parameter, string language)
        {
            TextBlock txt = new TextBlock();
            string str = (string)value;
            string[] strList = str.Split('=>');

            Run run2 = new Run();
            SolidColorBrush mySolidColorBrush = new SolidColorBrush(Color.FromArgb(255,0,0,255));
            run2.Foreground = mySolidColorBrush;
            txt.Inlines.Add(run2);

            return txt;
        }

        public object ConvertBack(object value, Type targetType, object parameter, string language)
        {
            return false;
        }

<TextBlock>
<Run Text="{Binding senselist,Converter={StaticResource textconvert}}" Foreground="Green" />
</TextBlock>

As results is "Windows.UI.Xaml.Controls.TextBlock". I had debugger then return txt is nullwhile "txt.Inlines.Add(run2);" is having data. Everyone help me to solve it.

Answer 4

As I told you, you should return a string an not a TextBlock from the converter. I don't know what you are trying to with the converter though. You are for example not setting the Text property of the Run that you create in there...

Just return a string:

public object Convert(object value, Type targetType, object parameter, string language)
        {
            string str = (string)value;
            string[] strList = str.Split('=>');

            if(strList.Count > 1)
  return strList[1];

            return str;
        }

        public object ConvertBack(object value, Type targetType, object parameter, string language)
        {
            return false;
        }

Please remember mark all helpful posts as answer and then start a new thread if you have a new question. Please don't post several questions in the same thread.

Answer 5

<TextBlock>
<Run Text="default colour..." />// Here is binding senselist but foreground is defaults??? but It also show fs up.
<Run Text="{Binding senselist,Converter={StaticResource textconvert}}" Foreground="Green" />
</TextBlock>
I still not understanding.
I have a string is "abc=fs"
I trying to your code then it just show "fs" up. I want both.
<Run Text="default colour..." /> is "abc"
<Run Text="{Binding senselist,Converter={StaticResource textconvert}}" Foreground="Green" /> is "fs"