恢复在屏幕上旋转值 [英] Restore values on screen rotation

问题描述

我已经创建了几个TextViews编程。当屏幕旋转，我失去所有添加的文本的意见和他们的文本值。什么是拯救他们和旋转后恢复的最佳途径。我使用的是tablelayout并添加行每行有四个textviews。我不想prevent设备旋转。

I have created several TextViews programmatically. When screen rotates I loose all added text views and their text values. What is the best way to save them and restore after rotation. I am using a tablelayout and adding rows each row has four textviews. I did not want to prevent device rotation.

推荐答案

您应该使用的onSaveInstanceState保存状态，然后重新创建它的onCreate。这同时适用于活动和片段，但我相信在方法上的知名度是一个有点不同（他们是公众片段）。

You should use onSaveInstanceState to save your state, and then recreate it in onCreate. This works for both Activities and Fragments, but I believe the visibility on the methods is a bit different (they're public for Fragments).

@Override
protected void onSaveInstanceState(Bundle outState) {
    super.onSaveInstanceState(outState);
    outState.putString("text1", text1.getText().toString());
    // do this for each of your text views
    // You might consider using Bundle.putStringArray() instead
}

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    // initialize all your visual fields        

    if (savedInstanceState != null) {
        text1.setText(savedInstanceState.getString("text1", ""));
        // do this for each of your text views
    }
}

请注意，这是比使用onRetainNonConfigurationInstance好;该方法用于跨轮换（例如位图）实际上保持周围的物体，但是你想只存储字符串，从而使用捆绑为preferred。此外，onRetainNonConfigurationInstance不受片段的支持;它被替换setRetainInstance，你不希望使用出于同样的原因。

Note that this is better than using onRetainNonConfigurationInstance; that method is used to actually keep objects around across rotations (e.g. Bitmaps), however you want to just store the strings, and thus using a Bundle is preferred. Also, onRetainNonConfigurationInstance isn't supported by Fragments; it's been replaced with setRetainInstance, and you don't want to use that for the same reason.

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