|= 和 &= ~
private int mFlags;
public void setUserFixed(boolean userFixed) { if (userFixed) { mFlags |= PackageManager.FLAG_PERMISSION_USER_FIXED; } else { mFlags &= ~PackageManager.FLAG_PERMISSION_USER_FIXED; } }
public boolean isSystemFixed() { return (mFlags & PackageManager.FLAG_PERMISSION_SYSTEM_FIXED) != 0; }