Initial commit

app/src/main/java/com/youxuegu/MainActivity.java

@@ -4,6 +4,9 @@ import androidx.appcompat.app.AppCompatActivity;
 
 import android.os.Bundle;
 
+/**
+ * @author YoVinchen
+ */
 public class MainActivity extends AppCompatActivity {
 
     @Override

app/src/main/java/com/youxuegu/activity/RegisterActivity.java

@@ -6,6 +6,9 @@ import android.os.Bundle;
 
 import com.youxuegu.R;
 
+/**
+ * @author YoVinchen
+ */
 public class RegisterActivity extends AppCompatActivity {
 
     @Override
@@ -13,4 +16,5 @@ public class RegisterActivity extends AppCompatActivity {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_register);
     }
+
 }

app/src/main/java/com/youxuegu/activity/SplashActivity.java

@@ -14,6 +14,9 @@ import com.youxuegu.R;
 import java.util.Timer;
 import java.util.TimerTask;
 
+/**
+ * @author YoVinchen
+ */
 public class SplashActivity extends AppCompatActivity {
 
     private TextView tv_version;

app/src/main/java/com/youxuegu/utils/MD5Utils.java

@@ -0,0 +1,36 @@
+package com.youxuegu.utils;
+
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+
+/**
+ * @author YoVinchen
+ */
+public class MD5Utils {
+    /**
+     * 创建MD5加密方法md5()
+     */
+    public static String md5(String text) {
+        MessageDigest digest = null;
+        try {
+            digest = MessageDigest.getInstance("md5");
+            byte[] result = digest.digest(text.getBytes());
+            StringBuilder sb = new StringBuilder();
+            for (byte b : result) {
+                //将字节byte转换为int类型的数据
+                int number = b & 0xff;
+                //将int类型的数据转换为十六进制的字符串数据
+                String hex = Integer.toHexString(number);
+                if (hex.length() == 1) {
+                    sb.append("0" + hex);
+                } else {
+                    sb.append(hex);
+                }
+            }
+            return sb.toString();
+        } catch (NoSuchAlgorithmException e) {
+            e.printStackTrace();
+            return "";
+        }
+    }
+}

app/src/main/java/com/youxuegu/utils/UtilsHelper.java

@@ -0,0 +1,40 @@
+package com.youxuegu.utils;
+
+import android.content.Context;
+import android.content.SharedPreferences;
+import android.text.TextUtils;
+
+/**
+ * @author YoVinchen
+ */
+public class UtilsHelper {
+    /**
+     * 判断SharedPreferences文件中是否存在要保存的用户名
+     *
+     * @param context
+     * @param userName
+     * @return
+     */
+    public static boolean isExistUserName(Context context, String userName) {
+        boolean has_userName = false;
+        SharedPreferences sp = context.getSharedPreferences("loginInfo", Context.MODE_PRIVATE);
+        String spPsw = sp.getString(userName, "");
+        if (TextUtils.isEmpty(spPsw)) {
+            has_userName = true;
+        }
+        return has_userName;
+    }
+
+    public static void saveUserInfo(Context context, String userName, String psw) {
+        //将密码用MD5加密
+        String md5Psw = MD5Utils.md5(psw);
+        //获取SharedPreferences类的对象sp
+        SharedPreferences sp = context.getSharedPreferences("loginInfo", Context.MODE_PRIVATE);
+        //获取编辑器对象editor
+        SharedPreferences.Editor editor = sp.edit();
+        //将用户名和密码封装到编辑器对象editor中
+        editor.putString(userName, md5Psw);
+        //提交保存信息
+        editor.commit();
+    }
+}