Is checking SDK_INT enough or is lazy loading needed for using newer android APIs ? Why?

问题

Code such as :

    if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.GINGERBREAD)
        ed.apply();
    else ed.commit();

produces a warning in Froyo :

04-27 03:40:35.025: W/dalvikvm(3138): VFY: unable to resolve interface method 219: Landroid/content/SharedPreferences$Editor;.apply ()V

But I understand that in older devices this would be a RuntimeError which would abort the application (see here and here).

So is this way of conditionally calling new API (methods) safe in API 8 (Froyo) and above or there are cases where lazy loading is still needed ?

What changes on Dalvik made this possible ?

Related

• Android recommended way of safely supporting newer apis has error if the class implements a newer interface. Why?
• Android solving compatibility with SDK_INT hack; is this ok?
• Android Dalvik Verification in Eclair

回答1:

produces a warning in Froyo

This is perfectly normal.

But I understand that in older devices this would be a RuntimeError which would abort the application

For Android 1.x, yes.

So is this way of conditionally calling new API (methods) safe in API 8 (Froyo) and above

Yes.

What changes on Dalvik made this possible ?

It no longer "fails fast" when encountering an unidentified symbol, but instead waits to try again to resolve it when the statement is executed. By checking SDK_INT and ensure that the statement is not executed, you don't crash.

来源：https://stackoverflow.com/questions/20271593/is-checking-sdk-int-enough-or-is-lazy-loading-needed-for-using-newer-android-api