Activity reloads when orientation changes in Android
When my main activity starts after the splash screen it parses 4 big XML files. This takes a开发者_如何学JAVA few seconds and I'm able to hide this in the time the splash screen shows at startup.
But when the screen orientation changes or when I go back to the main activity after a sub-activity it parses again and thus fore my app 'hangs' for a few seconds and it doesn't respond or anything in that time.
I understand this is normal behaviour in Android, but isn't there a way to avoid this?
I read something about savedinstancestate, but I can't seem to understand the docs..
add this code in your android manifest file in every activity node if you're targeting API level 12 or less.
android:configChanges="orientation|keyboardHidden"
For level 13 and onwards you also have to include "screensize", i.e.:
android:configChanges="orientation|keyboardHidden|screenSize"
now paste this code in your every activity's java classes.
@Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
// Checks the orientation of the screen
if (newConfig.orientation == Configuration.ORIENTATION_LANDSCAPE) {
Toast.makeText(this, "landscape", Toast.LENGTH_SHORT).show();
} else if (newConfig.orientation == Configuration.ORIENTATION_PORTRAIT){
Toast.makeText(this, "portrait", Toast.LENGTH_SHORT).show();
}
// Checks whether a hardware keyboard is available
if (newConfig.hardKeyboardHidden == Configuration.HARDKEYBOARDHIDDEN_NO) {
Toast.makeText(this, "keyboard visible", Toast.LENGTH_SHORT).show();
} else if (newConfig.hardKeyboardHidden == Configuration.HARDKEYBOARDHIDDEN_YES) {
Toast.makeText(this, "keyboard hidden", Toast.LENGTH_SHORT).show();
}
}
You could prevent this by adding android:configChanges="orientation" to your activity in AndroidManifest file.
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