Java – why doesn’t textview (with ID) automatically save its state?

My understanding is that all standard views with IDS should automatically save their state, and when I tried this example, I found it very confusing

I have only one activity and the main layout is shown below When I change the text of textview by clicking the button and then rotate the screen, textview actually saves its state, but when I rotate again, it resets to the default state

The same happens if I edit it in landscape and rotation: first rotate it and still save its state, but after another rotation (unless I change the text again), it will reset to the default value

I'm really confused now Someone can explain this behavior to me I can't find any other questions (or answers) that explain this particular behavior

activity_ main. In XML:

MainActivity. java：

Solution

If you look at the textview source (especially textview#onsaveinstancestate ()), you will see that text is saved only in two cases:

>This operation is performed when the user explicitly requires to set the freezetext flag to true through Android: freezestext = "true" or textview#setfreezestext (true) > when the text in textview is selected

In your case, both cases are wrong, so your text will be reset to its default state during the direction change

Simply changing the layout will solve the problem: