Get Binded Property Name - TypedBinding

Question

Get Binded Property Name - TypedBinding

vanKraster 201

I want to get the Property Name (string) or PropertyInfo (object) of the binded proberty inside a TypedBinding....

For now I use this and it works only if parent doesn't have a x:DataType

 private static MethodInfo _bindablePropertyGetContextMethodInfo = typeof(BindableObject).GetMethod("GetContext", BindingFlags.NonPublic | BindingFlags.Instance);
        private static FieldInfo _bindablePropertyContextBindingFieldInfo;
        public static Binding GetBinding(this BindableObject self, BindableProperty property)
        {

        object bindablePropertyContext = _bindablePropertyGetContextMethodInfo.Invoke(self, new[] { property });

        if (bindablePropertyContext != null)
        {
            FieldInfo propertyInfo = _bindablePropertyContextBindingFieldInfo =
                _bindablePropertyContextBindingFieldInfo ??
                    bindablePropertyContext.GetType().GetField("Binding");

            var valued = propertyInfo.GetValue(bindablePropertyContext);
            if (valued is Binding)
                return (Binding)valued;
            else return null;
        }

        return null;

if it has a datatype the valued is of type

{Xamarin.Forms.Internals.TypedBinding<ViewModelNameAndPath,string>}
And it can't be casted to Binding, if I cast to BaseBinding it doesn't have the Path property.... How can I achieve this ?

Thanks

Wenyan Zhang (Shanghai Wicresoft Co,.Ltd.) 36,436 Reputation points Microsoft External Staff

2021-12-17T07:38:21.693+00:00

I'm not clear about what effect you want to achieve, would mind sharing more detail information or code snippets?
vanKraster 201 Reputation points

2021-12-17T09:35:23.277+00:00

I want to get the property name that was binded...

Let's say I bind a property Testo so I'll have a Step = {Binding Testo}, but on my control I wanted to know what was the real name of the property binded to my BindableProperty Step in this case Testo.
In my control i have a bindable property

public static readonly BindableProperty StepProperty =
BindableProperty.Create(propertyName: nameof(Step),
returnType: typeof(string),
declaringType: typeof(SsNumericEntry),
defaultValue: "");

I think it is quite difficult to know the exact name of the property binded inside the control..
Wenyan Zhang (Shanghai Wicresoft Co,.Ltd.) 36,436 Reputation points Microsoft External Staff

2021-12-20T09:39:36.153+00:00

Do you want the similar API ? This thread is about uwp, I'm afraid there is no such API for iOS and Android. I check Bind to an ancestor , I'm not sure if it is what you want.
Wenyan Zhang (Shanghai Wicresoft Co,.Ltd.) 36,436 Reputation points Microsoft External Staff

2022-01-04T02:26:14.853+00:00
Testo does not have to be a bindable property, so the "real" name is the same name. It likely has a backing field [1] and calls OnPropertyChanged, but that is not really necessary if the data won't change at runtime.

[1]

string _testo; public string Testo { get { return _testo; } set { if (_testo!= value) { _testo= value; OnPropertyChanged(); } } }
vanKraster 201 Reputation points

2022-01-04T06:40:58.6+00:00

Thanks for reply,
I have changed the logic in that component. It was a reusable component that have bindable properties and I was binding another viewmodel to the component, so when I wanted to change the text OnPropertyChanged(); was not working because it was on a different viewmodel and I was trying to change with reflection the value inside another viewmodel ( the parent ). But I think this is a wrong pattern so I have changed all logic inside in order to not bind another viewmodel inside component.
Wenyan Zhang (Shanghai Wicresoft Co,.Ltd.) 36,436 Reputation points Microsoft External Staff

2022-01-04T07:21:02.477+00:00

OK, thank you for your sharing.

Your answer

Wenyan Zhang (Shanghai Wicresoft Co,.Ltd.) 36,436 Reputation points Microsoft External Staff

2021-12-17T07:38:21.693+00:00

I'm not clear about what effect you want to achieve, would mind sharing more detail information or code snippets?
vanKraster 201 Reputation points

2021-12-17T09:35:23.277+00:00

I want to get the property name that was binded...

Let's say I bind a property Testo so I'll have a Step = {Binding Testo}, but on my control I wanted to know what was the real name of the property binded to my BindableProperty Step in this case Testo.
In my control i have a bindable property

public static readonly BindableProperty StepProperty =
BindableProperty.Create(propertyName: nameof(Step),
returnType: typeof(string),
declaringType: typeof(SsNumericEntry),
defaultValue: "");

I think it is quite difficult to know the exact name of the property binded inside the control..
Wenyan Zhang (Shanghai Wicresoft Co,.Ltd.) 36,436 Reputation points Microsoft External Staff

2021-12-20T09:39:36.153+00:00

Do you want the similar API ? This thread is about uwp, I'm afraid there is no such API for iOS and Android. I check Bind to an ancestor , I'm not sure if it is what you want.
Wenyan Zhang (Shanghai Wicresoft Co,.Ltd.) 36,436 Reputation points Microsoft External Staff

2022-01-04T02:26:14.853+00:00

Testo does not have to be a bindable property, so the "real" name is the same name. It likely has a backing field [1] and calls OnPropertyChanged, but that is not really necessary if the data won't change at runtime.

[1]

string _testo; public string Testo { get { return _testo; } set { if (_testo!= value) { _testo= value; OnPropertyChanged(); } } }
vanKraster 201 Reputation points

2022-01-04T06:40:58.6+00:00

Thanks for reply,
I have changed the logic in that component. It was a reusable component that have bindable properties and I was binding another viewmodel to the component, so when I wanted to change the text OnPropertyChanged(); was not working because it was on a different viewmodel and I was trying to change with reflection the value inside another viewmodel ( the parent ). But I think this is a wrong pattern so I have changed all logic inside in order to not bind another viewmodel inside component.
Wenyan Zhang (Shanghai Wicresoft Co,.Ltd.) 36,436 Reputation points Microsoft External Staff

2022-01-04T07:21:02.477+00:00

OK, thank you for your sharing.

Share via

Get Binded Property Name - TypedBinding

Your answer