创建 ActionBar Xamarin Android 的实例

Question

我在我的应用程序中使用了 ActionBar。我做了这样的事情：-

ActionBar.SetDisplayHomeAsUpEnabled(true);
ActionBar.SetHomeButtonEnabled(true);

但我收到如下编译错误：-

A object reference is required for the non-static field, method, or property 'Android.Support.V7.App.ActionBar.SetDisplayHomeAsUpEnabled(bool)'

如何创建 ActionBar 的实例，因为它是一个抽象类？

编辑：-

使用 waquaslam 的解决方案，我这样做了：-

public class Homescreen : ActionBarActivity
{

    private DrawerLayout _drawer;
    private MyActionBarDrawerToggle _drawerToggle;
    private ListView _drawerList;
    private static ActionBar ActionBar ;

    private string _drawerTitle;
    private string _title;
    private string[] _planetTitles;

    protected override void OnCreate(Bundle savedInstanceState)
    {
        base.OnCreate(savedInstanceState);

        SupportRequestWindowFeature(WindowCompat.FeatureActionBar);



        SetContentView(Resource.Layout.homescreen);




        _title = _drawerTitle = Title;
        _planetTitles = Resources.GetStringArray(Resource.Array.TitlesArray);
        _drawer = FindViewById<DrawerLayout>(Resource.Id.drawer_layout);
        _drawerList = FindViewById<ListView>(Resource.Id.left_drawer);

        _drawer.SetDrawerShadow(Resource.Drawable.drawer_shadow_dark, (int)GravityFlags.Left);

        _drawerList.Adapter = new ArrayAdapter<string>(this,
            Resource.Layout.drawerlistitem, _planetTitles);
        _drawerList.ItemClick += (sender, args) => SelectItem(args.Position);






        SupportActionBar.SetDisplayHomeAsUpEnabled(true);

        SupportActionBar.SetHomeButtonEnabled(true);

        //DrawerToggle is the animation that happens with the indicator next to the
        //ActionBar icon. 
        _drawerToggle = new MyActionBarDrawerToggle(this, _drawer,
                                                  Resource.Drawable.ic_drawer_light,
                                                  Resource.String.DrawerOpen,
                                                  Resource.String.DrawerClose);

        //You can alternatively use _drawer.DrawerClosed here
        _drawerToggle.DrawerClosed += delegate
        {
            ActionBar.Title = _title;
            //InvalidateOptionsMenu();
        };

        //You can alternatively use _drawer.DrawerOpened here
        _drawerToggle.DrawerOpened += delegate
        {
            ActionBar.Title = _drawerTitle;
            // InvalidateOptionsMenu();
        };

        _drawer.SetDrawerListener(_drawerToggle);

        if (null == savedInstanceState)
            SelectItem(0);

    }

现在我收到了NoClassDefinitionFoundError。

Answer 1

如果您使用的是 support.V7，请确保您的活动继承自 ActionBarActivity。

为了在兼容性库中获取 ActionBar 的引用，您必须需要使用以下内容：

SupportActionBar.SetDisplayHomeAsUpEnabled(true);
SupportActionBar.SetHomeButtonEnabled(true);

有关更多信息，请阅读this，其中的示例基于操作栏中的选项卡，但使用了支持库。