유형별로 WPF 창에서 모든 컨트롤 찾기

유형별로 WPF 창에서 모든 컨트롤 찾기

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Window에서 모든 컨트롤을 유형별로 찾는 방법을 찾고 있습니다.

예를 들어 : 모두 찾기 TextBoxes, 특정 인터페이스를 구현하는 모든 컨트롤 찾기 등

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이 트릭을해야합니다

public static IEnumerable<T> FindVisualChildren<T>(DependencyObject depObj) where T : DependencyObject
{
    if (depObj != null)
    {
        for (int i = 0; i < VisualTreeHelper.GetChildrenCount(depObj); i++)
        {
            DependencyObject child = VisualTreeHelper.GetChild(depObj, i);
            if (child != null && child is T)
            {
                yield return (T)child;
            }

            foreach (T childOfChild in FindVisualChildren<T>(child))
            {
                yield return childOfChild;
            }
        }
    }
}

그런 다음 컨트롤을 열거합니다.

foreach (TextBlock tb in FindVisualChildren<TextBlock>(window))
{
    // do something with tb here
}

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가장 쉬운 방법입니다.

IEnumerable<myType> collection = control.Children.OfType<myType>(); 

여기서 control은 창의 루트 요소입니다.

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@Mathias Lykkegaard Lorenzen의 제안을 따르고 LogicalTreeHelper를 사용하도록 @Bryce Kahle의 답변을 수정했습니다.

잘 작동하는 것 같습니다. ;)

    public static IEnumerable<T> FindLogicalChildren<T> ( DependencyObject depObj ) where T : DependencyObject {
        if( depObj != null ) {
            foreach( object rawChild in LogicalTreeHelper.GetChildren( depObj ) ){
                if( rawChild is DependencyObject ) {
                    DependencyObject child = (DependencyObject)rawChild;
                    if( child is T ) {
                        yield return (T)child;
                    }

                    foreach( T childOfChild in FindLogicalChildren<T>( child ) ) {
                        yield return childOfChild;
                    }
                }
            }
        }
    }

(여전히 @Benjamin Berry & @David R에서 언급 한대로 GroupBox 내부의 탭 컨트롤 또는 그리드를 확인하지 않습니다.) (또한 @noonand의 제안을 따르고 중복 자식을 제거했습니다! = null)

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헬퍼 클래스를 사용 VisualTreeHelper하거나 관심 LogicalTreeHelper있는 트리 에 따라 다를 수 있습니다. 둘 다 요소의 하위 요소를 가져 오는 메소드를 제공합니다 (구문이 약간 다르지만). 필자는 종종 이러한 클래스를 사용하여 특정 유형의 첫 번째 항목을 찾았지만 해당 유형의 모든 객체를 찾도록 쉽게 수정할 수 있습니다.

public static DependencyObject FindInVisualTreeDown(DependencyObject obj, Type type)
{
    if (obj != null)
    {
        if (obj.GetType() == type)
        {
            return obj;
        }

        for (int i = 0; i < VisualTreeHelper.GetChildrenCount(obj); i++)
        {
            DependencyObject childReturn = FindInVisualTreeDown(VisualTreeHelper.GetChild(obj, i), type);
            if (childReturn != null)
            {
                return childReturn;
            }
        }
    }

    return null;
}

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위의 여러 예제에서 사용 된 VisualTreeHelper.GetChildrenCount (depObj); 행은 특히 GroupBox에 Grid가 있고 Grid에 자식 요소가있는 GroupBox에 대해 0이 아닌 수를 반환하지 않는다는 것을 알았습니다. GroupBox에 둘 이상의 자식이 포함될 수 없기 때문에 이것이 Content 속성에 저장되어 있기 때문일 수 있습니다. GroupBox.Children 유형의 속성이 없습니다. 이 작업을 매우 효율적으로 수행하지는 않았지만이 체인에서 첫 번째 "FindVisualChildren"예제를 다음과 같이 수정했습니다.

    public IEnumerable<T> FindVisualChildren<T>(DependencyObject depObj) where T : DependencyObject 
    { 
        if (depObj != null) 
        {
            int depObjCount = VisualTreeHelper.GetChildrenCount(depObj); 
            for (int i = 0; i <depObjCount; i++) 
            { 
                DependencyObject child = VisualTreeHelper.GetChild(depObj, i); 
                if (child != null && child is T) 
                { 
                    yield return (T)child; 
                }

                if (child is GroupBox)
                {
                    GroupBox gb = child as GroupBox;
                    Object gpchild = gb.Content;
                    if (gpchild is T)
                    {
                        yield return (T)child; 
                        child = gpchild as T;
                    }
                }

                foreach (T childOfChild in FindVisualChildren<T>(child)) 
                { 
                    yield return childOfChild; 
                } 
            }
        }
    } 

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특정 유형의 모든 자식 목록을 얻으려면 다음을 사용할 수 있습니다.

private static IEnumerable<DependencyObject> FindInVisualTreeDown(DependencyObject obj, Type type)
{
    if (obj != null)
    {
        if (obj.GetType() == type)
        {
            yield return obj;
        }

        for (var i = 0; i < VisualTreeHelper.GetChildrenCount(obj); i++)
        {
            foreach (var child in FindInVisualTreeDown(VisualTreeHelper.GetChild(obj, i), type))
            {
                if (child != null)
                {
                    yield return child;
                }
            }
        }
    }

    yield break;
}

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예를 들어 탭 컨트롤의 자식 탭 컨트롤을 찾을 수 있도록 재귀를 약간 변경합니다.

    public static DependencyObject FindInVisualTreeDown(DependencyObject obj, Type type)
    {
        if (obj != null)
        {
            for (int i = 0; i < VisualTreeHelper.GetChildrenCount(obj); i++)
            {
                DependencyObject child = VisualTreeHelper.GetChild(obj, i);

                if (child.GetType() == type)
                {
                    return child;
                }

                DependencyObject childReturn = FindInVisualTreeDown(child, type);
                if (childReturn != null)
                {
                    return childReturn;
                }
            }
        }

        return null;
    }

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제네릭 구문을 사용하는 또 다른 컴팩트 버전이 있습니다.

    public static IEnumerable<T> FindLogicalChildren<T>(DependencyObject obj) where T : DependencyObject
    {
        if (obj != null) {
            if (obj is T)
                yield return obj as T;

            foreach (DependencyObject child in LogicalTreeHelper.GetChildren(obj).OfType<DependencyObject>()) 
                foreach (T c in FindLogicalChildren<T>(child)) 
                    yield return c;
        }
    }

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그리고 이것이 위로 작동하는 방식입니다

    private T FindParent<T>(DependencyObject item, Type StopAt) where T : class
    {
        if (item is T)
        {
            return item as T;
        }
        else
        {
            DependencyObject _parent = VisualTreeHelper.GetParent(item);
            if (_parent == null)
            {
                return default(T);
            }
            else
            {
                Type _type = _parent.GetType();
                if (StopAt != null)
                {
                    if ((_type.IsSubclassOf(StopAt) == true) || (_type == StopAt))
                    {
                        return null;
                    }
                }

                if ((_type.IsSubclassOf(typeof(T)) == true) || (_type == typeof(T)))
                {
                    return _parent as T;
                }
                else
                {
                    return FindParent<T>(_parent, StopAt);
                }
            }
        }
    }

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VisualTreeHelper 사용은 Visual 또는 Visual3D에서 파생 된 컨트롤에서만 작동합니다. 다른 요소 (예 : TextBlock, FlowDocument 등)도 검사해야하는 경우 VisualTreeHelper를 사용하면 예외가 발생합니다.

필요한 경우 논리 트리로 대체되는 대안이 있습니다.

http://www.hardcodet.net/2009/06/finding-elements-in-wpf-tree-both-ways

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I wanted to add a comment but I have less than 50 pts so I can only "Answer". Be aware that if you use the "VisualTreeHelper" method to retrieve XAML "TextBlock" objects then it will also grab XAML "Button" objects. If you re-initialize the "TextBlock" object by writing to the Textblock.Text parameter then you will no longer be able to change the Button text using the Button.Content parameter. The Button will permanently show the text written to it from the Textblock.Text write action (from when it was retrieved --

foreach (TextBlock tb in FindVisualChildren<TextBlock>(window))
{
// do something with tb here
   tb.Text = ""; //this will overwrite Button.Content and render the 
                 //Button.Content{set} permanently disabled.
}

To work around this, you can try using a XAML "TextBox" and add methods (or Events) to mimic a XAMAL Button. XAML "TextBox" is not gathered by a search for "TextBlock".

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My version for C++/CLI

template < class T, class U >
bool Isinst(U u) 
{
    return dynamic_cast< T >(u) != nullptr;
}

template <typename T>
    T FindVisualChildByType(Windows::UI::Xaml::DependencyObject^ element, Platform::String^ name)
    {
        if (Isinst<T>(element) && dynamic_cast<Windows::UI::Xaml::FrameworkElement^>(element)->Name == name)
        {
            return dynamic_cast<T>(element);
        }
        int childcount = Windows::UI::Xaml::Media::VisualTreeHelper::GetChildrenCount(element);
        for (int i = 0; i < childcount; ++i)
        {
            auto childElement = FindVisualChildByType<T>(Windows::UI::Xaml::Media::VisualTreeHelper::GetChild(element, i), name);
            if (childElement != nullptr)
            {
                return childElement;
            }
        }
        return nullptr;
    };

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For some reason, none of the answers posted here helped me to get all controls of given type contained in a given control in my MainWindow. I needed to find all menu items in one menu to iterate them. They were not all direct descendants of the menu, so i managed to collect only the first lilne of them using any of the code above. This extension method is my solution for the problem for anyone who will continue to read all the way down here.

public static void FindVisualChildren<T>(this ICollection<T> children, DependencyObject depObj) where T : DependencyObject
    {
        if (depObj != null)
        {
            var brethren = LogicalTreeHelper.GetChildren(depObj);
            var brethrenOfType = LogicalTreeHelper.GetChildren(depObj).OfType<T>();
            foreach (var childOfType in brethrenOfType)
            {
                children.Add(childOfType);
            }

            foreach (var rawChild in brethren)
            {
                if (rawChild is DependencyObject)
                {
                    var child = rawChild as DependencyObject;
                    FindVisualChildren<T>(children, child);
                }
            }
        }
    }

Hope it helps.

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The accepted answer returns the discovered elements more or less unordered, by following the first child branch as deep as possible, while yielding the discovered elements along the way, before backtracking and repeating the steps for not yet parsed tree branches.

If you need the descendent elements in descending order, where the direct children will be yielded first, then their children and so on, the following algorithm will work:

public static IEnumerable<T> GetVisualDescendants<T>(DependencyObject parent, bool applyTemplates = false)
    where T : DependencyObject
{
    if (parent == null || !(child is Visual || child is Visual3D))
        yield break;

    var descendants = new Queue<DependencyObject>();
    descendants.Enqueue(parent);

    while (descendants.Count > 0)
    {
        var currentDescendant = descendants.Dequeue();

        if (applyTemplates)
            (currentDescendant as FrameworkElement)?.ApplyTemplate();

        for (var i = 0; i < VisualTreeHelper.GetChildrenCount(currentDescendant); i++)
        {
            var child = VisualTreeHelper.GetChild(currentDescendant, i);

            if (child is Visual || child is Visual3D)
                descendants.Enqueue(child);

            if (child is T foundObject)
                yield return foundObject;
        }
    }
}

The resulting elements will be ordered from nearest to farthest. This will be useful e.g. if you are looking for the nearest child element of some type and condition:

var foundElement = GetDescendants<StackPanel>(someElement)
                       .FirstOrDefault(o => o.SomeProperty == SomeState);

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Really nice answer.

VB.NET version:

Public Shared Iterator Function FindVisualChildren(Of T As DependencyObject)(depObj As DependencyObject) As IEnumerable(Of T)
    If depObj IsNot Nothing Then
        For i As Integer = 0 To VisualTreeHelper.GetChildrenCount(depObj) - 1
            Dim child As DependencyObject = VisualTreeHelper.GetChild(depObj, i)
            If child IsNot Nothing AndAlso TypeOf child Is T Then
                Yield DirectCast(child, T)
            End If
            For Each childOfChild As T In FindVisualChildren(Of T)(child)
                Yield childOfChild
            Next
        Next
    End If
End Function

Usage (this disables all TextBoxes in a window):

        For Each tb As TextBox In FindVisualChildren(Of TextBox)(Me)
          tb.IsEnabled = False
        Next

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I found it easier without Visual Tree Helpers:

foreach (UIElement element in MainWindow.Children) {
    if (element is TextBox) { 
        if ((element as TextBox).Text != "")
        {
            //Do something
        }
    }
};

참고URL : https://stackoverflow.com/questions/974598/find-all-controls-in-wpf-window-by-type