onPreated（）onPause（）和onStop（）之間的活動

Question

我無法可靠地退出我的應用程序中的活動。當我按下設備上的「後退」按鈕或者我從按鈕單擊呼叫finish()時，活動顯然是隨機重新啓動。

示例活動：

[Activity(Label = "abc", ParentActivity = typeof(MainActivity))] 
public class ImpressumActivity : Activity 
{ 
    private static int _instancecounter; 
    private int _thisinstance; 
    protected override void OnCreate(Bundle bundle) 
    { 
     _thisinstance = _instancecounter++; 
     Console.WriteLine("Creating instance {0}", _thisinstance); 
     base.OnCreate(bundle); 
     SetContentView(Resource.Layout.Impressum); 
     Console.WriteLine("Created instance {0}", _thisinstance); 
    } 

    public override void Finish() 
    { 
     Console.WriteLine("Finishing instance {0}", _thisinstance); 
     base.Finish(); 
     Console.WriteLine("Finished instance {0}", _thisinstance); 
    } 

    protected override void OnStop() 
    { 
     Console.WriteLine("Stopping instance {0}", _thisinstance); 
     base.OnStop(); 
     Console.WriteLine("Stopped instance {0}", _thisinstance); 
    } 

    protected override void OnPause() 
    { 
     Console.WriteLine("Pausing instance {0}", _thisinstance); 
     base.OnPause(); 
     Console.WriteLine("Paused instance {0}", _thisinstance); 
    } 

    protected override void OnDestroy() 
    { 
     Console.WriteLine("Destroying instance {0}", _thisinstance); 
     base.OnDestroy(); 
     Console.WriteLine("Destroyed instance {0}", _thisinstance); 
    } 
} 

現在，我在MainActivity開始十一時二十分五十秒通過impressumButton.Click += delegate { StartActivity(typeof(ImpressumActivity)); };的activiy，然後我按後退按鈕，在11時20分53秒。活動「保持」在屏幕上;實際上它得到了重新創建，我可以從輸出中看到：

10-07 11:20:50.255 I/mono-stdout(6149): Creating instance 0 
10-07 11:20:50.275 I/mono-stdout(6149): Created instance 0 
10-07 11:20:50.275 D/Activity(6149): setTransGradationMode to true 
10-07 11:20:53.535 I/mono-stdout(6149): Finishing instance 0 
10-07 11:20:53.555 I/mono-stdout(6149): Finished instance 0 
10-07 11:20:53.565 I/mono-stdout(6149): Pausing instance 0 
10-07 11:20:53.585 I/mono-stdout(6149): Paused instance 0 
10-07 11:20:53.605 I/mono-stdout(6149): Creating instance 1 
10-07 11:20:53.625 I/mono-stdout(6149): Created instance 1 
10-07 11:20:53.625 D/Activity(6149): setTransGradationMode to true 
10-07 11:20:54.015 I/mono-stdout(6149): Stopping instance 0 
10-07 11:20:54.015 I/mono-stdout(6149): Stopped instance 0 
10-07 11:20:54.015 I/mono-stdout(6149): Destroying instance 0 
10-07 11:20:54.015 I/mono-stdout(6149): Destroyed instance 0 

我在其他活動中具有相同的行爲。我試過NoHistory=true，這有幫助，但打破了其他的事情（我想要在更復雜的活動中的通話記錄），有和沒有ParentActivity = ...，但我卡住了。

更新：這是一個可以重現的MainActivity（）行爲： （）：請注意，我描述的行爲並不總是顯示。當我第二次進入ImpressumActivity時，似乎出現主要是，或者更具體地說，我需要在第n次進入活動時按「返回」n（儘管它每次都被銷燬！）

[Activity(Label = "@string/MainHL", MainLauncher = true, Icon = "@drawable/icon")] 
public class MainActivity : Activity 
{ 
    protected override void OnCreate(Bundle bundle) 
    { 
     base.OnCreate(bundle); 
     SetContentView(Resource.Layout.Main); 
    } 

    protected override void OnResume() 
    { 
     base.OnResume(); 
     var impressumButton = FindViewById<Button>(Resource.Id.impressum); 
     impressumButton.Click += delegate { StartActivity(typeof (ImpressumActivity)); }; 
    } 
} 

Answer 1

確實，這是問題所在。每次OnResume發生線路點擊事件，但您不釋放它。它會導致點擊後創建許多新的活動實例。而不是在OnCreate中點擊線路事件，你會沒事的。