[cpp][uwp] c++ winrt How to get app width and bind it to a Slider

Question

in I am trying to bind the upper end of a Slider to the current width of the app. It needs to look like,

< Slider x:Name="Slider1" Width="200" Minimum="50" Maximum="Page-Width" StepFrequency="10"

How can I get the page width in c++ winrt? How can I listen to a change event for when the window is resized and update the slider?

Answer 1

Hello,

​Welcome to Microsoft Q&A!

How to get app width

You can get the current width of window by using Window::Current().Bounds().Width method.

How can I listen to a change event for when the window is resized and update the slider?

There is a CoreWindow.SizeChanged Event can be used to listen for window size changes. You can directly change the Maximum in code-behind or create a ViewModel to bind to the Maximum of Slider and change the property of ViewModel to change the Maximum.

#include "winrt/Windows.UI.Core.h"

MainPage::MainPage()
{
    InitializeComponent();
    Window::Current().CoreWindow().SizeChanged([this](Windows::UI::Core::CoreWindow const&, Windows::UI::Core::WindowSizeChangedEventArgs const&) {
        Slider1().Maximum(Windows::UI::Xaml::Window::Current().Bounds().Width);
    });
}