小编Mah*_*man的帖子

我需要使用GoogleSignIn按钮登录并获取用户的名称以将其显示在导航栏标题中的TextView中,但我无法访问它.

MainActivity.java

 public class MainActivity extends AppCompatActivity
 implements NavigationView.OnNavigationItemSelectedListener, 
 GoogleApiClient.OnConnectionFailedListener {

ImageView photoImageViewe;
TextView nameTextView, emailTextView, txt3ady;

private GoogleApiClient googleApiClient;

@Override
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    //Drawer Inflater
    DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
    ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
            this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
    drawer.setDrawerListener(toggle);
    toggle.syncState();
    NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
    navigationView.setNavigationItemSelectedListener(this);

    nameTextView = (TextView) findViewById(R.id.nameTextView);
    emailTextView = (TextView) findViewById(R.id.emailTextView);
    photoImageViewe = (ImageView) findViewById(R.id.photoImageView);

    //Google SignIn
    GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
            .requestEmail()
            .build(); …

在我的项目中,我有一个文本框.我假设用户输入浮点变量或文本.如果用户输入float变量我需要检查这个变量,如果它实际上是一个float类型!

我想一些如何返回true或false来自float.Parse(String).可能吗？!