Java 如何添加按钮“toast message”；onClick"；零碎

我想在用户单击按钮时显示一条Toast消息

我尝试了许多解决方案，但对我不起作用

这是密码

Java“AccountFragment”

XML“片段账户” 我用过onClick

<Button
    android:id="@+id/button_login_google"
    android:layout_width="261dp"
    android:layout_height="50dp"
    android:layout_marginTop="50dp"
    android:background="@drawable/account_view2"
    android:text="Login with Google"
    android:onClick="Tosta"
    android:textColor="#fff"
    android:textSize="18dp"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toBottomOf="@+id/textView_login" />

查看以下内容：

     public class AccountFragment extends Fragment {

        Button btn;

        @Nullable
        @Override
        public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_account, container, false);

           btn = (Button) rootView.findViewById(R.id.button_login_google);
        btn.setOnClickListener(this);
            return rootView;
        }

        // display message for the user
        @Override
        public void onClick(View v) {
            // Toast here
    Toast.makeText(getActivity(),  "toast", Toast.LENGTH_LONG).show();
        }
}

您也可以尝试以下方法：

btn.setOnClickListener(new OnClickListener() {

                    @Override
                    public void onClick(View arg0) {

                    Toast.makeText(getActivity(),  "toast", Toast.LENGTH_LONG).show();

                    }
                });

看看这个：

     public class AccountFragment extends Fragment {

        Button btn;

        @Nullable
        @Override
        public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
            View rootView = inflater.inflate(R.layout.fragment_account, container, false);

           btn = (Button) rootView.findViewById(R.id.button_login_google);
        btn.setOnClickListener(this);
            return rootView;
        }

        // display message for the user
        @Override
        public void onClick(View v) {
            // Toast here
    Toast.makeText(getActivity(),  "toast", Toast.LENGTH_LONG).show();
        }
}

您也可以尝试以下方法：

btn.setOnClickListener(new OnClickListener() {

                    @Override
                    public void onClick(View arg0) {

                    Toast.makeText(getActivity(),  "toast", Toast.LENGTH_LONG).show();

                    }
                });