c# - OnResume() 在 Xamarin Droid 中与 TabGroupActivity 一起使用时未在子 Activity 中调用

Question

我在 Xamarin 中使用 Tabgroupactivity 来开发一个机器人应用程序。我有一个包含 4 个子 Activity 的 TabGroupActivity。

OnResume() 未在任何子 Activity 中调用。

谁能帮我找到正确的解决方案，为什么它没有被调用!!或者我的代码有什么错误吗？

TabGroupActivity.cs

namespace RB.Droid
{
[Activity (Label = "TabGroupActivity")]         
public class TabGroupActivity : ActivityGroup
{


    private List<string> _idList;

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

        if (_idList == null)
            _idList = new List<string> ();



    }


    public void StartChildActivity (string id, Intent intent)
    {
        intent.AddFlags (ActivityFlags.ClearTop);

        var manager = new LocalActivityManager (this, false);

        var window = MainTabActivity.localActivityManager.StartActivity (id, intent);
        if (window != null) {
            _idList.Add (id);
            SetContentView (window.DecorView);
        }
    }

    public override void FinishActivityFromChild (Activity child, int requestCode)
    {
        var manager = new LocalActivityManager (this, false);
        var index = _idList.Count - 1;

        if (index < 1) {
            Finish ();
            return;
        }

        MainTabActivity.localActivityManager.DestroyActivity (_idList [index], true);
        _idList.RemoveAt (index);
        index--;
        var lastId = _idList [index];
        var lastIntent = MainTabActivity.localActivityManager.GetActivity (lastId).Intent;
        var newWindow = MainTabActivity.localActivityManager.StartActivity (lastId, lastIntent);
        SetContentView (newWindow.DecorView);     
    }

    public override bool OnKeyDown (Keycode keyCode, KeyEvent e)
    {
        if (keyCode == Keycode.Back) {
            return true;
        }
        return base.OnKeyDown (keyCode, e);
    }

    public override bool OnKeyUp (Keycode keyCode, KeyEvent e)
    {
        if (keyCode == Keycode.Back) {
            OnBackPressed ();
            return true;
        }
        return base.OnKeyUp (keyCode, e);
    }

    public override void OnBackPressed ()
    {
        var length = _idList.Count;
        if (length > 1) {
            var manager = new LocalActivityManager (this, false);

            var current = MainTabActivity.localActivityManager.GetActivity (_idList [length - 1]);
            FinishActivityFromChild (current, 0);
        }
    }


}
}

SettingsActivityGroup.cs

namespace RB.Droid
{

[Activity (Label = "SettingsActivityGroup")]            
public class SettingsActivityGroup : TabGroupActivity
{
    protected override void OnCreate (Bundle bundle)
    {
        base.OnCreate (bundle);

        // Create your application here
        StartChildActivity ("Settings", new Intent (this, typeof(Settings)));
    }
}
}

设置.cs

namespace RB.Droid
{

[Activity (Label = "Settings")]         
public class Settings : Activity
{
    protected override void OnCreate (Bundle bundle)
    {
        base.OnCreate (bundle);

        // Create your application here
        TextView tv = new TextView (this);
        tv.Text = "Settings";
        SetContentView (tv);
    }

    protected override void OnResume ()
    {
        base.OnResume ();

        Toast.MakeText (this, "ON RESUME NOT CALLED", ToastLength.Long);
    }
}
}

Answer 1

使用 OnStart 方法来做到这一点。我们使用此方法在显示 View 时加载/刷新一些 ui 数据。

OnResume:当另一个 Activity 结束时，该 Activity 进入暂停状态。在这种情况下，当用户按下后退按钮时，将调用 onResume。

有关 Activity 生命周期的更多信息和很好的解释:See this answer