diff --git a/MainActivity.java b/MainActivity.java
new file mode 100644
index 0000000..b2f7f42
--- /dev/null
+++ b/MainActivity.java
@@ -0,0 +1,206 @@
+package com.example.sparrownotes;
+
+import android.content.Intent;
+import android.os.Bundle;
+import android.text.method.HideReturnsTransformationMethod;
+import android.text.method.PasswordTransformationMethod;
+import android.view.View;
+import android.widget.Button;
+import android.widget.CheckBox;
+import android.widget.EditText;
+import android.widget.ImageView;
+import android.widget.TextView;
+import android.widget.Toast;
+
+import androidx.appcompat.app.AppCompatActivity;
+
+import com.example.sparrownotes.bean.UserBean;
+import com.example.sparrownotes.dao.UserDao;
+import com.example.sparrownotes.util.Constant;
+import com.example.sparrownotes.util.SharedPreferenceUtil;
+
+import java.util.List;
+
+import butterknife.BindView;
+import butterknife.ButterKnife;
+import butterknife.OnClick;
+
+/**
+ * 登录页面
+ * @author Horsen
+ */
+public class MainActivity extends AppCompatActivity {
+
+    @BindView(R.id.img_icon)
+    ImageView imgIcon;
+    @BindView(R.id.check_auto_login)
+    CheckBox checkAutoLogin;
+    @BindView(R.id.check_remember_pwd)
+    CheckBox checkRememberPwd;
+    @BindView(R.id.text_forget_pwd)
+    TextView textForgetPwd;
+    @BindView(R.id.btn_login)
+    Button btnLogin;
+    @BindView(R.id.edit_username)
+    EditText editUsername;
+    @BindView(R.id.edit_password)
+    EditText editPassword;
+    @BindView(R.id.text_register)
+    TextView textRegister;
+    @BindView(R.id.check_hide_pwd)
+    CheckBox checkHidePwd;
+
+    private static final String TAG = "MainActivity";
+    private UserDao userDao;
+    private String textUserName;
+    private String textPassword;
+
+    private static boolean REMEMBER_PWD = false;
+    private static boolean AUTO_LOGIN = false;
+    SharedPreferenceUtil spu;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_main);
+        ButterKnife.bind(this);
+        userDao = new UserDao(this);
+        spu = SharedPreferenceUtil.getInstance(this);
+    }
+
+    @Override
+    protected void onStart() {
+        super.onStart();
+        Intent intent = getIntent();
+        // 如果注册过
+        if (intent.getBooleanExtra(Constant.HAS_REGISTERED, false)) {
+            intent.removeExtra(Constant.HAS_REGISTERED);
+            editUsername.setText(spu.getString(Constant.USER_NAME));
+            editPassword.setText(spu.getString(Constant.PASSWORD));
+        } else {
+            // 如果勾选记住密码
+            if (spu.getBoolean(Constant.REMEMBER_PWD)) {
+                checkRememberPwd.setChecked(true);
+                editUsername.setText(spu.getString(Constant.USER_NAME));
+                editPassword.setText(spu.getString(Constant.PASSWORD));
+            } else {
+                editUsername.setText("");
+                editPassword.setText("");
+            }
+            // 如果勾选自动登录
+            if (spu.getBoolean(Constant.AUTO_LOGIN)) {
+                checkAutoLogin.setChecked(true);
+                Intent intentLogin = new Intent(MainActivity.this, HomeActivity.class);
+                startActivity(intentLogin);
+            }
+        }
+    }
+
+    @OnClick({R.id.check_auto_login, R.id.check_remember_pwd, R.id.btn_login, R.id.text_forget_pwd, R.id.text_register, R.id.check_hide_pwd})
+    public void onViewClicked(View view) {
+        switch (view.getId()) {
+            case R.id.check_auto_login:
+                // 勾选自动登录时自动勾选记住密码
+                if (checkAutoLogin.isChecked()) {
+                    checkRememberPwd.setChecked(true);
+                    AUTO_LOGIN = true;
+                    REMEMBER_PWD = true;
+                } else {
+                    AUTO_LOGIN = false;
+                }
+                break;
+            case R.id.check_remember_pwd:
+                // 勾掉记住密码时自动勾掉自动登录
+                if (!checkRememberPwd.isChecked()) {
+                    checkAutoLogin.setChecked(false);
+                    AUTO_LOGIN = false;
+                    REMEMBER_PWD = false;
+                } else {
+                    REMEMBER_PWD = true;
+                }
+                break;
+            case R.id.btn_login:
+                // 检查非空
+                if (isNotEmpty()) {
+                    // 获得用户输入
+                    getEditText();
+                    // 检查用户名密码
+                    if (checkUser()) {
+                        // 存入sp 用于接下来页面的显示
+                        spu.putBoolean(Constant.REMEMBER_PWD, REMEMBER_PWD);
+                        spu.putBoolean(Constant.AUTO_LOGIN, AUTO_LOGIN);
+                        spu.putString(Constant.USER_NAME, textUserName);
+                        spu.putString(Constant.PASSWORD, textPassword);
+                        spu.putInt(Constant.USER_ID, getUserID());
+                        Intent intentLogin = new Intent(MainActivity.this, HomeActivity.class);
+                        startActivity(intentLogin);
+                        finish();
+                    } else {
+                        Toast.makeText(this, "用户名或密码错误", Toast.LENGTH_SHORT).show();
+                    }
+                } else {
+                    Toast.makeText(this, "用户名或密码不能为空", Toast.LENGTH_SHORT).show();
+                }
+                break;
+            case R.id.text_forget_pwd:
+                // 忘记密码
+                Intent intentFind = new Intent(MainActivity.this, FindPwdActivity.class);
+                startActivity(intentFind);
+                break;
+            case R.id.text_register:
+                // 注册
+                Intent intentRegister = new Intent(MainActivity.this, RegisterActivity.class);
+                startActivity(intentRegister);
+                break;
+            case R.id.check_hide_pwd:
+                if (checkHidePwd.isChecked()) {
+                    // 将密码显示出来
+                    editPassword.setTransformationMethod(HideReturnsTransformationMethod.getInstance());
+                } else {
+                    // 隐藏密码
+                    editPassword.setTransformationMethod(PasswordTransformationMethod.getInstance());
+                }
+                // 将光标移动到文本最后
+                editPassword.setSelection(editPassword.getText().toString().length());
+                break;
+            default:
+                break;
+        }
+    }
+
+    /**
+     * 检验输入非空
+     *
+     * @return
+     */
+    public boolean isNotEmpty() {
+        return !"".equals(editUsername.getText().toString()) &&
+                !"".equals(editPassword.getText().toString());
+    }
+
+    /**
+     * 从控件中得到输入值
+     */
+    public void getEditText() {
+        textUserName = editUsername.getText().toString();
+        textPassword = editPassword.getText().toString();
+    }
+
+    /**
+     * 验证用户名密码
+     */
+    public boolean checkUser() {
+        List<UserBean> userBeans = userDao.queryByUserNameAndPassword(textUserName, textPassword);
+        return userBeans.size() != 0;
+    }
+
+    /**
+     * 获得用户ID
+     *
+     * @return
+     */
+    public int getUserID() {
+        List<UserBean> userBeans = userDao.queryByUserNameAndPassword(textUserName, textPassword);
+        return userBeans.get(0).getUserID();
+    }
+}
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