如何可靠测量Android软导航高度？

import android.content.res.Resources;
import android.util.DisplayMetrics;

public int getNavigationBarHeight() {
    Resources resources = getResources();
    int resourceId = resources.getIdentifier("navigation_bar_height", "dimen", "android");
    if (resourceId > 0) {
        return resources.getDimensionPixelSize(resourceId);
    }
    return 0;
}

int navigationBarHeight = getNavigationBarHeight();