Android：当我按系统后退菜单时，从子活动返回后，父母活动数据丢失

Question

I have following 3 activities:

1. Groups
2. Items
3. Item Details

I am using SQLite to manage data. When I press a group, first 10 items of the specified groups will appear at Items activity. Pressing load more button, next 10 items will appear and so on. And when I press an Item on Item Activity, Item details will appear at Item Details Activity. I have set Items Activity as parent for Items Details Activity for Menu Action Bar.

The problem is when I press system back button at Item Details Activity, Items Activity screen is appearing with Empty data. The screen should be displayed with Items of the specified groups. I noticed that onCreate function is being called after pressing back button. But, the screen should display previous result set.

How to display previous result set at Items Activity?

Answer 1

In your ItemDetails activity put this code.

@Override
public boolean onKeyDown(int keyCode, KeyEvent event)  {
if (Integer.parseInt(android.os.Build.VERSION.SDK) > 5
        && keyCode == KeyEvent.KEYCODE_BACK
        && event.getRepeatCount() == 0) {
    Log.d("CDA", "onKeyDown Called");
    onBackPressed();
    return true; 
}
return super.onKeyDown(keyCode, event);
}