Hiding the ellipsis within an AppBar

生来就可爱ヽ(ⅴ<●) 提交于 2019-12-03 02:10:32
Justin XL

First, try not to use AppBar in your new UWP apps.

The CommandBar control for universal Windows apps has been improved to provide a superset of AppBar functionality and greater flexibility in how you can use it in your app. You should use CommandBar for all new universal Windows apps on Windows 10.

You can read more about it here.

Both CommandBar and AppBar can be full styled and templated. This gives you the ability to remove whatever UI elements you don't want to display.

This is how you do it -

Open your page in Blend, right click on CommandBar > Edit Template > Edit a Copy. Then make sure you select Define in Application as currently there's a bug in Blend which will fail to generate the styles if you choose This document.

Once you have all the styles, find the MoreButton control and set its Visibility to Collapsed (or you can remove it but what if you realise you need it later?).

Then you should have a CommandBar without the ellipsis.

Update for 2017 The visibility of the Ellipsis button can now be found in the OverflowButtonVisibility Property of a CommandBar. As above set it to Collapsed to hide it.

If you want to hide this button globally it enough to add

<Style x:Key="EllipsisButton" TargetType="Button">
    <Setter Property="Visibility" Value="Collapsed"/>
</Style>

to global resource file

I know this question is is not active any more, but for sake of completion I am proposing my answer.

Instead of changing the visibility by using Styles, I have written an AttachedProperty extension that is able to hide/show the MoreButton via data binding. This way you can show/hide it conditionally as you please.

Usage is as simple as binding your property to the extension:

<CommandBar extensions:CommandBarExtensions.HideMoreButton="{Binding MyBoolean}">
    ...
</CommandBar>

The extension code is as follows:

public static class CommandBarExtensions
{
    public static readonly DependencyProperty HideMoreButtonProperty =
        DependencyProperty.RegisterAttached("HideMoreButton", typeof(bool), typeof(CommandBarExtensions), 
            new PropertyMetadata(false, OnHideMoreButtonChanged));

    public static bool GetHideMoreButton(UIElement element)
    {
        if (element == null) throw new ArgumentNullException(nameof(element));
        return (bool)element.GetValue(HideMoreButtonProperty);
    }

    public static void SetHideMoreButton(UIElement element, bool value)
    {
        if (element == null) throw new ArgumentNullException(nameof(element));
        element.SetValue(HideMoreButtonProperty, value);
    }

    private static void OnHideMoreButtonChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        var commandBar = d as CommandBar;
        if (e == null || commandBar == null || e.NewValue == null) return;
        var morebutton = commandBar.FindDescendantByName("MoreButton");
        if (morebutton != null)
        {
            var value = GetHideMoreButton(commandBar);
            morebutton.Visibility = value ? Visibility.Collapsed : Visibility.Visible;
        }
        else
        {
            commandBar.Loaded += CommandBarLoaded;
        }
    }

    private static void CommandBarLoaded(object o, object args)
    {
        var commandBar = o as CommandBar;
        var morebutton = commandBar?.FindDescendantByName("MoreButton");
        if (morebutton == null) return;
        var value = GetHideMoreButton(commandBar);
        morebutton.Visibility = value ?  Visibility.Collapsed : Visibility.Visible;
        commandBar.Loaded -= CommandBarLoaded;
    }
}

On initial binding it uses the Loaded event to apply the hiding once it has been loaded. The FindDescendantByName is another extension method that iterates the visual tree. You might want to create or grab one if your solution does not yet contain it.

Michael Woolsey

Since I cannot add a comment to the particular answer I'll post it here.

The following page gives many examples that will find the child object to compliment @RadiusK's answer.

How can I find WPF controls by name or type?

The one that worked for me specifically in UWP was:

/// <summary>
/// Finds a Child of a given item in the visual tree. 
/// </summary>
/// <param name="parent">A direct parent of the queried item.</param>
/// <typeparam name="T">The type of the queried item.</typeparam>
/// <param name="childName">x:Name or Name of child. </param>
/// <returns>The first parent item that matches the submitted type parameter. 
/// If not matching item can be found, 
/// a null parent is being returned.</returns>
public static T FindChild<T>(DependencyObject parent, string childName) where T : DependencyObject
{
    // Confirm parent and childName are valid. 
    if (parent == null)
        return null;

    T foundChild = null;

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

        // If the child is not of the request child type child
        T childType = child as T;
        if (childType == null)
        {
            // recursively drill down the tree
            foundChild = FindChild<T>(child, childName);

            // If the child is found, break so we do not overwrite the found child. 
            if (foundChild != null)
                break;
        }
        else if (!string.IsNullOrEmpty(childName))
        {
            var frameworkElement = child as FrameworkElement;

            // If the child's name is set for search
            if (frameworkElement != null && frameworkElement.Name == childName)
            {
                // if the child's name is of the request name
                foundChild = (T)child;
                break;
            }
        }
        else
        {
            // child element found.
            foundChild = (T)child;
            break;
        }
    }

    return foundChild;
}

Calling the code like this:

var morebutton = FindChild<Button>(commandBar, "MoreButton");

Building upon @RadiusK's answer (which has some issues), I came up with a conciser alternative that's tested and works:

using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Media;

namespace Linq
{
    public static class CommandBarExtensions
    {
        public static readonly DependencyProperty HideMoreButtonProperty = DependencyProperty.RegisterAttached("HideMoreButton", typeof(bool), typeof(CommandBarExtensions), new PropertyMetadata(false, OnHideMoreButtonChanged));
        public static bool GetHideMoreButton(CommandBar d)
        {
            return (bool)d.GetValue(HideMoreButtonProperty);
        }
        public static void SetHideMoreButton(CommandBar d, bool value)
        {
            d.SetValue(HideMoreButtonProperty, value);
        }
        static void OnHideMoreButtonChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            var CommandBar = d as CommandBar;
            if (CommandBar != null)
            {
                var MoreButton = CommandBar.GetChild<Button>("MoreButton") as UIElement;
                if (MoreButton != null)
                {
                    MoreButton.Visibility = !(e.NewValue as bool) ? Visibility.Visible : Visibility.Collapsed;
                }
                else CommandBar.Loaded += OnCommandBarLoaded;
            }
        }

        static void OnCommandBarLoaded(object sender, RoutedEventArgs e)
        {
            var CommandBar = sender as CommandBar;

            var MoreButton = CommandBar?.GetChild<Button>("MoreButton") as UIElement;
            if (MoreButton != null)
            {
                MoreButton.Visibility = !(GetHideMoreButton(CommandBar) as bool) ? Visibility.Visible : Visibility.Collapsed;
                CommandBar.Loaded -= OnCommandBarLoaded;
            }
        }

        public static T GetChild<T>(this DependencyObject Parent, string Name) where T : DependencyObject
        {
            if (Parent != null)
            {
                for (int i = 0, Count = VisualTreeHelper.GetChildrenCount(Parent); i < Count; i++)
                {
                    var Child = VisualTreeHelper.GetChild(Parent, i);

                    var Result = Child is T && !string.IsNullOrEmpty(Name) && (Child as FrameworkElement)?.Name == Name ? Child as T : Child.GetChild<T>(Name);
                    if (Result != null)
                        return Result;
                }
            }
            return null;
        }
    }
}
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