Question

编辑：我是Android新手，我不想使用数据库或等来存储凭据，我只是想让if语句工作......

所以，我正在尝试为应用程序创建一个简单的登录系统。我以后按登录，toast返回false消息，但是字符串是true，当我试图验证那些时我做错了什么？（如果声明）

   package com.example.reevo.a02activities07;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

import org.w3c.dom.Text;

import static android.R.attr.button;
import static android.R.attr.onClick;
import static android.icu.lang.UCharacter.GraphemeClusterBreak.T;

public class MainActivity extends AppCompatActivity {

    TextView textViewUsername, textViewPassword;
    Button loginButton;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        textViewPassword = (TextView) findViewById(R.id.userInput);
        textViewUsername = (TextView) findViewById(R.id.passwordInput);
        loginButton = (Button) findViewById(R.id.buttonLogin);

    }

    public void onClick(View view){

        if (textViewUsername.getText().toString().equals("admin") && textViewPassword.getText().toString().equals("pass")){
            Toast.makeText(getApplicationContext(), "Succesfull!", Toast.LENGTH_SHORT).show();
        }   else Toast.makeText(getApplicationContext(), "Wrong credentials!", Toast.LENGTH_SHORT).show();

    }
}

Answer 1

textViewPassword指向R.id.userInput，textViewUsername指向R.id.passwordInput。你应该改变它

Answer 2

你的绑定控件有错误检查它使用这个

textViewPassword = (TextView) findViewById(R.id.passwordInput);
textViewUsername = (TextView) findViewById(R.id.userInput);

这是

的内容

textViewPassword = (TextView) findViewById(R.id.userInput);
textViewUsername = (TextView) findViewById(R.id.passwordInput);

Veryfing一个String返回false？

2 个答案: