Question

我在App.xaml.cs中添加了一个带有3个按钮的appbar，将它放在每个页面上，但我有一个页面，我想另外添加另一个按钮。

我做的是，我从App.xaml.cs获得带有3个默认按钮的appbar，然后我添加了另一个按钮。问题是当它被添加时，当我更改页面时，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。

我想知道是否可以仅为具有4个按钮的页面复制此appbar ...（Icloneable？但我不知道如何：/）你怎么看？我还要提一下，有些按钮使用导航去另一页。

这是我的代码：

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);
    }

在我希望另外还有一个按钮的页面中：

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);
    }

提前谢谢

Answer 1

离开带有额外按钮的页面时，您可以删除该按钮。

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

全局appBar，为此特定页面的appbar添加其他按钮

1 个答案: