新增数据库连接

app/src/main/java/com/example/myapplication/MainActivity.java

@@ -12,6 +12,7 @@ import androidx.appcompat.app.AppCompatActivity;
 public class MainActivity extends AppCompatActivity {
     Button loginB, newUser;
     EditText usernameET, passwordET;
+    SqliteDbManager instance;
 
     private static final String correctName = "admin";
     private static final String correctPassword = "rootadmin";
@@ -23,14 +24,13 @@ public class MainActivity extends AppCompatActivity {
         initView();
         loginB.setOnClickListener(v -> {
             if (submit()) {
-                System.out.println(usernameET.getText());
                 Toast.makeText(MainActivity.this, "登录成功", Toast.LENGTH_LONG).show();
                 Intent intent = new Intent();
                 ComponentName componentName = new ComponentName(MainActivity.this, InfoActivity.class);
                 intent.setComponent(componentName);
                 intent.putExtra("username", usernameET.getText());
                 startActivity(intent);
-            }else{
+            } else {
                 Toast.makeText(MainActivity.this, "账号或密码输入错误", Toast.LENGTH_LONG).show();
             }
         });
@@ -50,10 +50,13 @@ public class MainActivity extends AppCompatActivity {
         usernameET = findViewById(R.id.username);
         passwordET = findViewById(R.id.password);
         newUser = findViewById(R.id.newUser);
+        instance = SqliteDbManager.getInstance();
     }
 
     boolean submit() {
-        return getUsername().equals(correctName) && getPassword().equals(correctPassword);
+        instance.setSqliteDbOpen(this);
+        return instance.queryTb("person", getUsername(), getPassword());
+//        return getUsername().equals(correctName) && getPassword().equals(correctPassword);
     }
 
     String getUsername() {

app/src/main/java/com/example/myapplication/MainActivity2.java

@@ -43,6 +43,8 @@ public class MainActivity2 extends Activity {
     private Button btnReg, btnYear, back;
     private List<String> cityList;
 
+    SqliteDbManager instance = SqliteDbManager.getInstance();
+
     //JSONObject对象，处理一个一个的对象
     //JSONObject对象，处理一个一个集合或者数组
     //保存带集合的json字符串
@@ -75,6 +77,7 @@ public class MainActivity2 extends Activity {
                 Intent intent = new Intent(MainActivity2.this, MainActivity.class);
                 intent.putExtra("username", edtNewUserName.getText().toString());
                 intent.putExtra("password", edtPwd1.getText().toString());
+                this.register();
                 startActivity(intent);
             });
             builder.setNegativeButton("否", (dialog, which) -> isYes = false);
@@ -103,8 +106,13 @@ public class MainActivity2 extends Activity {
         });
     }
 
+    private void register(){
+        String username = edtNewUserName.getText().toString();
+        String password = edtPwd1.getText().toString();
+        instance.insertTb("person", username, password);
+    }
     void initView() {
-
+        instance.setSqliteDbOpen(this);
         edtNewUserName = this.findViewById(R.id.edtNewUserName);
         edtPwd1 = this.findViewById(R.id.edtPwd);
         edtPwd2 = this.findViewById(R.id.edtSndPwd);

app/src/main/java/com/example/myapplication/PeopleActivity.java

@@ -1,15 +1,10 @@
 package com.example.myapplication;
 
 import android.app.Activity;
-import android.content.ComponentName;
-import android.content.Intent;
-import android.graphics.Bitmap;
-import android.graphics.BitmapFactory;
 import android.os.Bundle;
 import android.widget.Button;
 import android.widget.ImageView;
 import android.widget.TextView;
-import android.widget.Toast;
 
 public class PeopleActivity extends Activity {
     private Button ylp, qxs, lsg, tyy, djx;
@@ -19,7 +14,7 @@ public class PeopleActivity extends Activity {
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
-        setContentView(R.layout.people);
+        setContentView(R.layout.test);
         initView();
         ylp.setOnClickListener(v -> {
             imageView.setImageResource(R.drawable.ylp);
@@ -50,6 +45,6 @@ public class PeopleActivity extends Activity {
         tyy = findViewById(R.id.tyy);
         djx = findViewById(R.id.djx);
         textView = findViewById(R.id.peopletext);
-        imageView = findViewById(R.id.peoplezp);
+        imageView = findViewById(R.id.peopleImage);
     }
 }

app/src/main/java/com/example/myapplication/PersonSQLiteOpenHelper.java

@@ -0,0 +1,34 @@
+package com.example.myapplication;
+
+import android.content.Context;
+import android.database.sqlite.SQLiteDatabase;
+import android.database.sqlite.SQLiteOpenHelper;
+
+import java.security.AccessControlContext;
+
+
+public class PersonSQLiteOpenHelper extends SQLiteOpenHelper {
+    /**
+     * 构造方法
+     * @param context
+     */
+    public PersonSQLiteOpenHelper(Context context) {
+        super(context,"person",null,1);
+    }
+    /**
+     * 数据库第一次创建完成的回调
+     */
+    @Override
+    public void onCreate(SQLiteDatabase db) {
+//        String sql="create table person (id integer primary key autoincrement,name varchar(10) not null default '')";
+        String sql="create table person(id integer primary key autoincrement,username varchar(50),password varchar(50),sex varchar(50),address varchar(50))";
+        db.execSQL(sql);
+    }
+
+    @Override
+    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
+        // TODO Auto-generated method stub
+
+    }
+
+}

app/src/main/java/com/example/myapplication/SqliteDbManager.java

@@ -0,0 +1,134 @@
+package com.example.myapplication;
+
+import android.annotation.SuppressLint;
+import android.content.ContentValues;
+import android.content.Context;
+import android.database.Cursor;
+import android.database.sqlite.SQLiteDatabase;
+import android.database.sqlite.SQLiteOpenHelper;
+import android.util.Log;
+
+public class SqliteDbManager
+{
+    private static SqliteDbManager mInstance = null;
+    private SQLiteDatabase mDb = null;
+    private PersonSQLiteOpenHelper mDbHelper = null;
+
+    public static SqliteDbManager getInstance()
+    {
+        if (mInstance == null)
+        {
+            mInstance = new SqliteDbManager();
+        }
+        return mInstance;
+    }
+
+    public void setSqliteDbOpen(Context context)
+    {
+        mDbHelper = new PersonSQLiteOpenHelper(context.getApplicationContext());
+        mDb = mDbHelper.getWritableDatabase();
+    }
+
+    public void insertTb(String tbName, String username, String password)
+    {
+        openDb();
+        //方法一：
+        ContentValues contentValues = new ContentValues();
+        contentValues.put("username",username);
+        contentValues.put("password",password);
+//        contentValues.put("sex","男");
+        mDb.insert(tbName,null,contentValues);
+        //方法二：
+//        mDb.execSQL("insert into "+tbName+" (username,password) values ('李四',20)");
+//        mDb.execSQL("insert into "+tbName+" (name,age,sex) values ('王五',22,'女')");
+//        mDb.execSQL("insert into "+tbName+" (name,age,sex) values ('哈利',21,'男')");
+        closeDb();
+    }
+
+    public void deleteTb(String tbName)
+    {
+        openDb();
+        //方法一：
+        mDb.delete(tbName,"name=?",new String[]{"zhangsan"});
+        //方法二：
+        mDb.execSQL("delete from "+tbName+" where name = '李四'");
+        closeDb();
+    }
+
+    public void updateTb(String tbName)
+    {
+        openDb();
+        //方法一：
+        ContentValues contentValues = new ContentValues();
+        contentValues.put("name","隔壁老王");
+        contentValues.put("sex","男");
+        mDb.update(tbName,contentValues,"name=?",new String[]{"王五"});
+        //方法二：
+        mDb.execSQL("update "+tbName+" set name = '哈利波特',age = '16' where name = '哈利'");
+        closeDb();
+    }
+
+    public boolean queryTb(String tbName, String username, String password)
+    {
+        openDb();
+//        //方法一：
+//        Cursor cursor = mDb.query(tbName, new String[]{"name","sex","age"}, "name=?", new String[]{"隔壁老王"}, null, null, null);
+//        //将光标移动到下一行，从而判断该结果集是否还有下一条数据；如果有则返回true，没有则返回false
+//        if (null != cursor)
+//        {
+//            while (cursor.moveToNext())
+//            {
+//                String name = cursor.getString(cursor.getColumnIndex("name"));
+//                int age = cursor.getInt(cursor.getColumnIndex("age"));
+//                String sex = cursor.getString(cursor.getColumnIndex("sex"));
+//                Log.i("????","name = "+name+"; age = "+age+"; sex = "+sex);
+//            }
+//            cursor.close();
+//        }
+        //方法二：使用sql语句
+        Cursor rawQuery = mDb.rawQuery("select * from " + tbName+" where username=? and password=?", new String[]{username,password});
+//        Cursor rawQuery = mDb.rawQuery("select * from " + tbName,null);
+        if (null != rawQuery)
+        {
+            while (rawQuery.moveToNext())
+            {
+                @SuppressLint("Range") String _id = rawQuery.getString(rawQuery.getColumnIndex("id"));
+                @SuppressLint("Range") String name = rawQuery.getString(rawQuery.getColumnIndex("username"));
+//                int age = rawQuery.getInt(rawQuery.getColumnIndex("age"));
+//                String sex = rawQuery.getString(rawQuery.getColumnIndex("sex"));
+                Log.i("????","_id = "+_id+"; name = "+name);
+                return true;
+            }
+            rawQuery.close();
+        }
+        closeDb();
+        return false;
+    }
+
+    /**
+     *  创建或打开一个可以读的数据库
+     */
+    private void openDb() {
+        if (this.mDbHelper != null) {
+            try {
+                mDb = mDbHelper.getWritableDatabase();
+            } catch (Exception e) {
+                mDb = mDbHelper.getReadableDatabase();
+                e.printStackTrace();
+            }
+        }
+    }
+
+    /**
+     *  关闭数据库
+     */
+    private void closeDb() {
+        try {
+            if (mDb != null) {
+                mDb.close();
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+    }
+}

app/src/main/res/layout/people.xml

@@ -1,120 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<LinearLayout 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"
-    android:orientation="vertical">
-
-    <LinearLayout
-        android:layout_width="match_parent"
-        android:layout_height="10dp">
-
-        <!--        <ImageView-->
-        <!--            android:layout_width="wrap_content"-->
-        <!--            android:layout_height="match_parent"-->
-        <!--            android:src="@drawable/nike"></ImageView>-->
-
-    </LinearLayout>
-
-
-    <LinearLayout
-        android:layout_width="match_parent"
-        android:layout_height="match_parent"
-        android:orientation="horizontal">
-
-        <FrameLayout
-            android:id="@+id/fl_left"
-            android:layout_width="wrap_content"
-            android:layout_height="match_parent"
-            android:layout_weight="1"
-            android:background="@color/white">
-
-            <LinearLayout
-                android:layout_width="match_parent"
-                android:layout_height="match_parent"
-                android:orientation="vertical">
-
-                <Button
-                    android:id="@+id/ylp"
-                    android:layout_width="match_parent"
-                    android:layout_height="wrap_content"
-                    android:background="@color/white"
-                    android:text="孔子"
-                    android:textColor="@color/black"
-                    android:textSize="20dp"></Button>
-
-                <Button
-                    android:id="@+id/djx"
-                    android:layout_width="match_parent"
-                    android:layout_height="wrap_content"
-                    android:background="@color/white"
-                    android:text="宋庆龄"
-                    android:textColor="@color/black"
-                    android:textSize="20dp"></Button>
-
-                <Button
-                    android:id="@+id/tyy"
-                    android:layout_width="match_parent"
-                    android:layout_height="wrap_content"
-                    android:background="@color/white"
-                    android:text="宋美龄"
-                    android:textColor="@color/black"
-                    android:textSize="20dp"></Button>
-
-                <Button
-                    android:id="@+id/lsg"
-                    android:layout_width="match_parent"
-                    android:layout_height="wrap_content"
-                    android:background="@color/white"
-                    android:text="胡适"
-                    android:textColor="@color/black"
-                    android:textSize="20dp"></Button>
-
-                <Button
-                    android:id="@+id/qxs"
-                    android:layout_width="match_parent"
-                    android:layout_height="wrap_content"
-                    android:background="@color/white"
-                    android:text="钱学森"
-                    android:textColor="@color/black"
-                    android:textSize="20dp"></Button>
-            </LinearLayout>
-        </FrameLayout>
-
-        <FrameLayout
-            android:id="@+id/fl_right"
-            android:layout_width="wrap_content"
-            android:layout_height="match_parent"
-            android:layout_weight="2"
-            android:background="@color/nike">
-
-
-            <LinearLayout
-                android:layout_width="match_parent"
-                android:layout_height="wrap_content"
-                android:gravity="center"
-                android:orientation="vertical">
-
-                <ImageView
-                    android:id="@+id/kz"
-                    android:layout_width="100dp"
-                    android:layout_height="130dp"
-                    android:src="@drawable/kz"></ImageView>
-
-                <TextView
-                    android:id="@+id/peopletext"
-                    android:layout_width="match_parent"
-                    android:layout_height="wrap_content"
-                    android:layout_marginTop="10dp"
-                    android:text="孔子（公元前551年-公元前479年4月11日），子姓，孔氏，名丘，字仲尼，春秋时期鲁国陬邑（今山东省曲阜市）人，祖籍宋国栗邑（今河南省夏邑县），中国古代伟大的思想家、政治家、教育家，儒家学派创始人、“大成至圣先师”。"
-                    android:textSize="15dp"></TextView>
-            </LinearLayout>
-        </FrameLayout>
-
-        <!--    <ListView-->
-        <!--        android:id="@+id/lv"-->
-        <!--        android:layout_width="match_parent"-->
-        <!--        android:layout_height="wrap_content" />-->
-
-    </LinearLayout>
-</LinearLayout>

app/src/main/res/layout/test.xml

@@ -96,7 +96,7 @@
                 android:orientation="vertical">
 
                 <ImageView
-                    android:id="@+id/peoplezp"
+                    android:id="@+id/peopleImage"
                     android:layout_width="100dp"
                     android:layout_height="130dp"
                     android:src="@drawable/ylp"></ImageView>
@@ -111,10 +111,5 @@
             </LinearLayout>
         </FrameLayout>
 
-        <!--    <ListView-->
-        <!--        android:id="@+id/lv"-->
-        <!--        android:layout_width="match_parent"-->
-        <!--        android:layout_height="wrap_content" />-->
-
     </LinearLayout>
 </LinearLayout>