全局appBar，为特定页面在此appBar中添加其他按钮

Question

我在App.xaml.cs中添加了一个appbar与3个按钮，将其放在每个页面上，但我有一个页面，我想添加另一个按钮。

我要做的是，我从app . example .cs中获得appbar和我的3个默认按钮，然后我添加我的另一个按钮。问题是，当它被添加，当我改变页面，我添加的按钮保持可见…因此，这是对象引用的问题，因为每个页面引用相同的appbar。

我想知道是否有可能复制这个appbar只有4个按钮的页面…(iclonable ?但是我不知道怎么做:/)你觉得呢?我还应该提到，一些按钮使用导航到另一个页面。

下面是我的代码:

App.xaml.cs

private ApplicationBar _appBar;
public ApplicationBar AppBar { get { return _appBar; } } //property called in other page
//Method called in the constructor
private void BuildLocalizedApplicationBar()
    {
        // Set the page's ApplicationBar to a new instance of ApplicationBar.
        _appBar = new ApplicationBar();
        // Create a new button and set the text value to the localized string from AppResources.
        var appBarButtonScan = new ApplicationBarIconButton(new Uri("/Assets/AppBar/White/appbar.qr.png", UriKind.Relative));
        appBarButtonScan.Click += AppBarButtonScanOnClick;
        appBarButtonScan.Text = AppResources.Scan;
        var appBarButtonSearch = new ApplicationBarIconButton(new Uri("/Assets/AppBar/White/appbar.search.png", UriKind.Relative));
        appBarButtonSearch.Click += AppBarButtonSearchOnClick;
        appBarButtonSearch.Text = AppResources.Search;
        var appBarButtonFacebook = new ApplicationBarIconButton(new Uri("/Assets/AppBar/White/appbar.facebook.png", UriKind.Relative));
        appBarButtonFacebook.Click += AppBarButtonFacebookOnClick;
        appBarButtonFacebook.Text = AppResources.MyAccount;
        _appBar.Buttons.Add(appBarButtonScan);
        _appBar.Buttons.Add(appBarButtonSearch);
        _appBar.Buttons.Add(appBarButtonFacebook);
        // Create a new menu item with the localized string from AppResources.
        ApplicationBarMenuItem appBarMenuSettings = new ApplicationBarMenuItem(AppResources.SettingsTitle);
        _appBar.MenuItems.Add(appBarMenuSettings);
    }

在我想添加一个按钮的页面:

private void BuildLocalizedApplicationBar()
    {
        App _app = Application.Current as App; //in my page, it's an attribute that I initialize in my constructor.
        ApplicationBar = _app.AppBar; //get the appbar with 3 buttons from App.xaml.cs
        // Create new buttons and set the text value to the localized string from AppResources.
        ApplicationBarIconButton appBarButtonTagPlace = new ApplicationBarIconButton(new Uri("/Assets/AppBar/White/appbar.heart.outline.png", UriKind.Relative));
        appBarButtonTagPlace.Text = AppResources.TagThisPlaceTitle;
        appBarButtonTagPlace.Click += AppBarButtonTagPlaceOnClick;

        ApplicationBar.Buttons.Add(appBarButtonTagPlace);
    }

提前感谢

Answer 1

你可以在离开有额外按钮的页面时删除按钮。

protected override void OnNavigatingFrom(NavigatingCancelEventArgs e)
{
    ApplicationBar.Buttons.Remove(appBarButtonTagPlace);
    base.OnNavigatedFrom(e);
}