觅踪4

今天继续完善登录、注册功能，看似简单，实则不易

Mainactivity

package com.example.demo2;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.Button;
import android.content.Intent;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.RelativeLayout;
import android.widget.TextView;
import android.widget.Toast;
import androidx.appcompat.app.AppCompatActivity;
import java.util.ArrayList;

public class MainActivity extends AppCompatActivity implements View.OnClickListener{
    private DBOpenHelper mDBOpenHelper;
    private TextView mTvLoginactivityRegister;
    private RelativeLayout mRlLoginactivityTop;
    private EditText mEtLoginactivityUsername;
    private EditText mEtLoginactivityPassword;
    private LinearLayout mLlLoginactivityTwo;
    private Button mBtLoginactivityLogin;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        initView();
        mDBOpenHelper = new DBOpenHelper(this);
    }


    private void initView() {
        // 初始化控件
        mBtLoginactivityLogin = findViewById(R.id.bt_loginactivity_login);
        mTvLoginactivityRegister = findViewById(R.id.tv_loginactivity_register);
        mRlLoginactivityTop = findViewById(R.id.rl_loginactivity_top);
        mEtLoginactivityUsername = findViewById(R.id.et_loginactivity_username);
        mEtLoginactivityPassword = findViewById(R.id.et_loginactivity_password);
        mLlLoginactivityTwo = findViewById(R.id.ll_loginactivity_two);

        // 设置点击事件监听器
        mBtLoginactivityLogin.setOnClickListener(this);
        mTvLoginactivityRegister.setOnClickListener(this);
    }

    public void onClick(View view) {
        switch (view.getId()) {
            // 跳转到注册界面
            case R.id.tv_loginactivity_register:
                startActivity(new Intent(this, item1Activity.class));
                finish();
                break;
            case R.id.bt_loginactivity_login:
                String name = mEtLoginactivityUsername.getText().toString().trim();
                String password = mEtLoginactivityPassword.getText().toString().trim();
                if (!TextUtils.isEmpty(name) && !TextUtils.isEmpty(password)) {
                    ArrayList<User> data = mDBOpenHelper.getAllData();
                    boolean match = false;
                    for (int i = 0; i < data.size(); i++) {
                        User user = data.get(i);
                        if (name.equals(user.getName()) && password.equals(user.getPassword())) {
                            match = true;
                            break;
                        } else {
                            match = false;
                        }
                    }
                    if (match) {
                        Toast.makeText(this, "登录成功", Toast.LENGTH_SHORT).show();
                        Intent intent = new Intent(this, MainActivity.class);
                        startActivity(intent);
                        finish();//销毁此Activity
                    } else {
                        Toast.makeText(this, "用户名或密码不正确，请重新输入", Toast.LENGTH_SHORT).show();
                    }
                } else {
                    Toast.makeText(this, "请输入你的用户名或密码", Toast.LENGTH_SHORT).show();
                }
                break;
        }
    }
}

item1activity

package com.example.demo2;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ListView;
import android.widget.TextView;

public class item1Activity extends AppCompatActivity {

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            ListView lv_list = (ListView) findViewById(R.id.lv_list);
            lv_list.setAdapter(new MyAdapter());

        }
        private class MyAdapter extends BaseAdapter {
            @Override
            public int getCount() {
                return 5;//返回值决定ListView展示多少条数据
            }

            @Override
            public Object getItem(int position) {
                return null;
            }

            @Override
            public long getItemId(int position) {
                return 0;
            }

            @Override
            public View getView(int position, View convertView, ViewGroup parent) {

                View view = null;
                if (convertView == null) {
                    view = View.inflate(item1Activity.this, R.layout.item1, null);
                } else {
                    view = convertView;
                }


                return view;


            }
        }
    }