OnBackButtonPressed Not Firing Xamarin Forms

user_3355961 0
Viewed 7638

I am trying to prevent the user of my app from pressing the hardware back button. I have found this code snippet that is in the code behind the xaml file:

protected override bool OnBackButtonPressed()
    {
        return true;
    }

I have tried variations of this including using Boolean instead of Bool and returning base.functionname nothing seems to fire this method. Here is the bigger context:

Code behind:

namespace Watson.Views
{
    [XamlCompilation(XamlCompilationOptions.Compile)]
    public partial class StartScan : ContentPage
    {
        public StartScan()
        {
            InitializeComponent();
        }
        protected override bool OnBackButtonPressed()
        {
            return true;
        }
    }
}

This is the second page in the stack and disabling the button only needs to happen on this page only, no where else.

Any help would be appreciated.

xamarin.forms xamarin xaml c#
5 Answers

You can also add NavigationPage.SetHasBackButton property in the XAML

     NavigationPage.HasBackButton="True"

In the Content Page

user_128036950

You can do this way:

namespace Watson.Views
{
    [XamlCompilation(XamlCompilationOptions.Compile)]
    public partial class StartScan : ContentPage
    {
        public StartScan()
        {
            NavigationPage.SetHasBackButton(this, false);
            InitializeComponent();
        }
        protected override bool OnBackButtonPressed()
        {
            // you can put some actions here (for example, an dialog prompt, ...)
            return true;
        }
    }
}
user_88119710

For me it is working with the following code (Samsung Android)

protected override bool OnBackButtonPressed()
{
    //base.OnBackButtonPressed();
    browser.GoBack();
    return true;
}
user_14152050

OnBackButtonPressed firing when you click the back button on your device, not from your navigation page, do your logic in OnDisappearing!

user_90990800
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