2024.5.20

第五十二天

所花时间：2小时

代码量：200

博客量：1

了解到的知识点：团队作业2

登陆

package com.example.share.utils;

import android.content.Context;
import android.widget.Toast;

import androidx.appcompat.app.AlertDialog;

import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

/**
 * 自定义通用工具类
 */
public class CommonUtils {

    /**
     * 获取当前时间的字符串
     * @return "yyyy-MM-dd HH:mm:ss" 格式的时间字符串
     */
    public static String getDateStrFromNow(){
        DateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        return df.format(new Date());
    }

    /**
     * 从日期时间中获取时间字符串
     * @param dt 日期时间
     * @return "yyyy-MM-dd HH:mm:ss" 格式的时间字符串
     */
    public static String getStrFromDate(Date dt){
        DateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        return df.format(dt);
    }

    /**
     * 显示短消息
     * @param context 上下文
     * @param msg 要显示的消息
     */
    public static void showShortMsg(Context context, String msg){
        Toast.makeText(context, msg, Toast.LENGTH_SHORT).show();
    }

    /**
     * 显示长消息
     * @param context 上下文
     * @param msg 要显示的消息
     */
    public static void showLonMsg(Context context, String msg){
        Toast.makeText(context, msg, Toast.LENGTH_LONG).show();
    }

    /**
     * 显示消息对话框
     * @param context 上下文
     * @param msg 要显示的消息
     */
    public static void showDlgMsg(Context context, String msg){
        new AlertDialog.Builder(context)
                .setTitle("提示信息")
                .setMessage(msg)
                .setPositiveButton("确定", null)
                .setNegativeButton("取消", null)
                .create().show();
    }
}

package com.example.share;

import android.annotation.SuppressLint;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.os.Handler;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

//import androidx.activity.EdgeToEdge;
import androidx.appcompat.app.AppCompatActivity;
import androidx.core.graphics.Insets;
import androidx.core.view.ViewCompat;
import androidx.core.view.WindowInsetsCompat;

import com.example.share.register;
import com.example.share.dao.UserDao;
import com.example.share.utils.CommonUtils;

public class MainActivity extends AppCompatActivity implements View.OnClickListener {

    private Button LoginButton,SignUpButton;
    private EditText UserNameEdit,PassWordEdit;
    UserDao userDao;
    private Handler mainHandler;


    @SuppressLint("MissingInflatedId")
    @Override
    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        LoginButton = findViewById(R.id.LoginButton);
        SignUpButton=findViewById(R.id.SignUpButton);

        UserNameEdit = findViewById(R.id.UserNameEdit);
        PassWordEdit = findViewById(R.id.PassWordEdit);

        userDao=new UserDao();
        mainHandler=new Handler(getMainLooper());

        LoginButton.setOnClickListener(this);
        SignUpButton.setOnClickListener(this);
    }


    @Override
    public void onClick(View v) {
        if (v.getId() == R.id.LoginButton) {
            String name=UserNameEdit.getText().toString().trim();
            String password=PassWordEdit.getText().toString().trim();

            new Thread(new Runnable() {
                @Override
                public void run() {

                    String Password="";
                    String TeacherPassword="";
                    Password=userDao.login(name);

                    if(password.equals(Password)){
                        Intent intent=new Intent(getApplicationContext(), DongtaiActivity.class);
                        Bundle bundle=new Bundle();
                        bundle.putString("name",name);
                        intent.putExtras(bundle);
                        startActivity(intent);
                        mainHandler.post(new Runnable() {
                            @Override
                            public void run() {
                                CommonUtils.showShortMsg(MainActivity.this,"登陆成功");
                                SharedPreferences sharedPref = getSharedPreferences("app_prefs", Context.MODE_PRIVATE);
                                SharedPreferences.Editor editor = sharedPref.edit();
                                editor.putString("username", name);
                                editor.apply();
                                Intent intent=new Intent(getApplicationContext(), DongtaiActivity.class);
                            }
                        });

                    }
                    else if(password.equals(TeacherPassword)){
                        Intent intent=new Intent(getApplicationContext(), DongtaiActivity.class);
                        startActivity(intent);
                        mainHandler.post(new Runnable() {
                            @Override
                            public void run() {
                                CommonUtils.showShortMsg(MainActivity.this,"登陆成功");
                                Intent intent=new Intent(getApplicationContext(), DongtaiActivity.class);
                            }
                        });

                    }
                    else{
                        mainHandler.post(new Runnable() {
                            @Override
                            public void run() {
                                CommonUtils.showShortMsg(MainActivity.this,"登陆失败");
                            }
                        });
                    }
                }
            }).start();
        }
        else if(v.getId()==R.id.SignUpButton){
            Intent intent=new Intent(getApplicationContext(), register.class);
            startActivity(intent);
        }
    }




    @Override
    public void onPointerCaptureChanged(boolean hasCapture) {
        super.onPointerCaptureChanged(hasCapture);
    }
}

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <!--使用线性布局-->
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="vertical"
        android:background="#F5F5F5">

        <!--Logo-->
        <ImageView
            android:id="@+id/LogoImage"
            android:layout_width="match_parent"
            android:layout_height="120dp"
            android:layout_marginTop="100dp"
            />

        <!--标题-->
        <TextView
            android:id="@+id/TitleText"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_margin="25dp"
            android:text="登录"
            android:gravity="center"
            android:textStyle="italic"
            android:textColor="#808080"
            android:textSize="30dp" />

        <!--嵌套线性布局-->
        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:orientation="vertical">

            <!--嵌套线性布局-->
            <LinearLayout
                android:id="@+id/UserNameLayout"
                android:layout_width="match_parent"
                android:layout_height="match_parent">

                <!--用户名输入-->
                <EditText
                    android:id="@+id/UserNameEdit"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:padding="15dp"
                    android:layout_marginLeft="20dp"
                    android:layout_marginRight="20dp"
                    android:layout_marginTop="10dp"
                    android:layout_marginBottom="15dp"
                    android:background="@drawable/translucent_edit"
                    android:hint="输入用户名"
                    android:textSize="24dp"
                    android:singleLine="true" />

            </LinearLayout>

            <!--嵌套线性布局-->
            <LinearLayout
                android:id="@+id/PassWordLayout"
                android:layout_width="match_parent"
                android:layout_height="wrap_content">

                <!--密码输入-->
                <EditText
                    android:id="@+id/PassWordEdit"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:padding="15dp"
                    android:layout_marginLeft="20dp"
                    android:layout_marginRight="20dp"
                    android:layout_marginTop="10dp"
                    android:layout_marginBottom="15dp"
                    android:background="@drawable/translucent_edit"
                    android:hint="输入用户密码"
                    android:textSize="24dp"
                    android:maxLength="16"
                    android:singleLine="true"
                    android:inputType="textPassword" />

            </LinearLayout>

            <!--嵌套线性布局-->
            <LinearLayout
                android:id="@+id/LayoutButton"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="horizontal">

                <!--登录按钮-->
                <androidx.appcompat.widget.AppCompatButton
                    android:id="@+id/LoginButton"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:padding="15dp"
                    android:layout_margin="15dp"
                    android:layout_weight="1"
                    android:textColor="@color/white"
                    android:background="@drawable/translucent_button"
                    android:text="登   录"
                    android:textSize="24dp" />

                <!--注册按钮-->
                <androidx.appcompat.widget.AppCompatButton
                    android:id="@+id/SignUpButton"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:padding="15dp"
                    android:layout_margin="15dp"
                    android:layout_weight="1"
                    android:textColor="@color/white"
                    android:background="@drawable/translucent_button"
                    android:text="注   册"
                    android:textSize="24dp" />

            </LinearLayout>

        </LinearLayout>

    </LinearLayout>
</androidx.constraintlayout.widget.ConstraintLayout>