Android的生命周期：在数据填写活动在onStart（）或onResume（）？ [英] Android lifecycle: Fill in data in activity in onStart() or onResume()?

问题描述

的如果您通过光标获取数据，并在屏幕上的数据，如（设置窗口标题，在在onStart）或<$ C填写$ C> onResume（）

在onStart（）似乎逻辑的地方，因为在在onStart（）活动已经可以显示，尽管在​​后台运行。值得注意的是我有一个问题管理对话框，使我重新考虑这一点。如果用户旋转屏幕，同时对话框仍然打开， onCreateDialog（）和上prepareDialog（）被称为的 在onStart（）和 onResume（）。如果必须基于数据的对话框，你需要有之前 onResume数据（）。

onStart() would seem the logical place because after onStart() the Activity can already be displayed, albeit in the background. Notably I was having a problem with a managed dialog that made me rethink this. If the user rotates the screen while the dialog is still open, onCreateDialog() and onPrepareDialog() are called between onStart() and onResume(). If the dialog needs to be based on the data you need to have the data before onResume().

如果我对在onStart正确的是（）那么为什么在记事本的例子在<$ C $这样做给了一个坏榜样C> onResume（）？见<一href=\"http://developer.android.com/resources/samples/NotePad/src/com/example/android/notepad/NoteEditor.html\">http://developer.android.com/resources/samples/NotePad/src/com/example/android/notepad/NoteEditor.html NoteEditor.java线176（标题= mCursor.getString ... ）。

If I'm correct about onStart() then why does the Notepad example give a bad example by doing it in onResume()? See http://developer.android.com/resources/samples/NotePad/src/com/example/android/notepad/NoteEditor.html NoteEditor.java line 176 (title = mCursor.getString...).

另外，如果我的活动启动另一Actvity /对话框，它改变了我的光标正在跟踪的数据。即使在最简单的情况，这是否意味着我必须手动的更新我的previous屏幕（在主要活动对话框侦听器），或者说我必须要注册一个ContentObserver，因为我不再更新的onResume（）（虽然我两次，当然更新）？

Also, what if my Activity launches another Actvity/Dialog that changes the data my cursor is tracking. Even in the simplest case, does that mean that I have to manually update my previous screen (a listener for a dialog in the main activity), or alternatively that I have to register a ContentObserver, since I'm no longer updating the data in onResume() (though I could update it twice of course)?

我知道这是一个基本的问题，但对话只是在最近，出乎我的意料，让我意识到这一点。

I know it's a basic question but the dialog only recently, to my surprise, made me realize this.

推荐答案

要解答有关问题NoteEditor，只需看看你举一个以上的线，你会看到...

To answer your question about NoteEditor, simply take a look at the lines above the one you cite and you'll see...

    // Requery in case something changed while paused (such as the title)
    mCursor.requery();

注释似乎可以解释这一切。虽然我没有通过记事本的例子了自己，它出现在作者（S）正在建设中，从变化虽然NoteEditor暂停（然后再恢复）的恢复能力。

The comment seems to explain it all. Although I haven't gone through the NotePad example myself, it appears the author(s) are building in the ability to recover from changes whilst the NoteEditor is paused (and then resumed).

由于GSree解释（虽然我打字本），有不正确或错误的答案，它只是依赖于需要在活动生命周期的这点做的事情。

As GSree explains (whilst I was typing this), there isn't a right or wrong answer and it simply depends on what needs to be done at which point of the Activity life-cycle.

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