通过一个活动的引用到另一个活动 [英] Pass reference of one Activity to another Activity

问题描述

我知道我可以使用意图传递活动之间的一些价值观。 不过，如果我想整个活动传递到另一个活动，我认为这是不好的做法。 是否有另一种方式来做到这一点？

I know that I can pass some values between Activities using intent. However, if I want to pass whole Activity to another Activity I think it is not good approach. Is there another way to do that?

我设置的活动中，我改变了一些颜色。所以，当我回到我的主要活动，我想应用这些颜色。要做到这一点，我需要访问MainActivity领域后，我改变颜色值，所以里面的preferenceActivity。换句话说，我想有机会获得由preferenceActivity类主要活动领域。任何想法？

I have Settings Activity in which I am changing some Colors. So after I come back to my Main Activity I would like to apply those colors. To do this, I need access to MainActivity fields after I change Color value, so inside PreferenceActivity. In other words, I want to have access to Main activity fields from PreferenceActivity class. Any ideas?

推荐答案

您应该使用共享preference ，然后访问，在你的主要活动。我建议你​​读了在 http://developer.android.com/guide/topics /ui/settings.html 因为它看起来像你实现你的设置活动不正确。你可能是特别感兴趣的部分是在读preferences部分。不过，我强烈建议你仔细阅读了整个事情，然后实现你的设置的正确方法。

You should be using a SharedPreference and then accessing that in your main activity. I recommend you reading up at http://developer.android.com/guide/topics/ui/settings.html because it seems like you are implementing your settings activity incorrectly. The part you might be specifically interested in is the "Read Preferences" section. However, I strongly suggest you read through the whole thing and then implement your settings the proper way.

与3种不同的方式（即我能想到的）更新答案：的

Updated answer with the 3 different ways (that I can think of):

1），使用启动preference活动 startActivityForResult（），然后在 onActivityResult（）访问在共享preference 键，让你的必要的修改。 查看 这里

1) Start your preference activity using startActivityForResult(), then in your onActivityResult() access the SharedPreference and make your necessary changes. See here

2）注册一个共享preferenceChangeListener 您MainActivity，当任何变化发生在你的共享preference将被称为。 查看 <一个href="http://stackoverflow.com/questions/2542938/shared$p$pferences-onshared$p$pferencechangelistener-not-being-called-consistently/3104265#3104265">here 进行了详细的讨论。同时看到我的初步回应。

2) Register a SharedPreferenceChangeListener with your MainActivity, which will be called when any changes happen to your SharedPreference. See here for a detailed discussion. Also see my initial response.

3）在你的MainActivity的 onResume（），进入共享preference 键，然后进行更改那里。我不喜欢这种方法，因为你会被搞乱 onResume（）有更多的逻辑，你也可能必须有一个保持变量的状态跟踪一个变量，你有兴趣

3) In your MainActivity's onResume(), access the SharedPreference and then make your changes there. I do not like this method because you will be cluttering onResume() with more logic and you will also probably have to have a variable that keeps track of the state of the variable you are interested in.

我会亲自去与选项2，因为回调是为这一确切目的创建的。

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