记事本（一）

功能：（一）可添加文字内容并查询内容，并且可以查看保存时间，用户在登录的同时记事本显示xx用户欢迎你！；（二）可创建用户登录，并正常使用忘记密码，注册用户等功能运行效果：

界面设计（一）：添加标题内容

界面设计（二）：记事本界面布局

界面设计（三）：记事本模板

代码在这里：（一）添加标题内容

package com.example.jishiben;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.InputType;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

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

public class AddNoteActivity extends AppCompatActivity {

    private Button button;
    private EditText title,content;
    private DBAdapter dbAdapter;
    private String createDate;
    private String name;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_add_note);
        button=findViewById(R.id.bt_save);
        title=findViewById(R.id.et_title);
        content=findViewById(R.id.et_content);
        Intent intent=this.getIntent();
        name=intent.getStringExtra("name");
        content.setInputType(InputType.TYPE_TEXT_FLAG_MULTI_LINE);
        SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date curDate =new Date(System.currentTimeMillis());
        createDate=formatter.format(curDate);
        dbAdapter =new DBAdapter(this);
        dbAdapter.open();
        button.setonClickListener(new View.onClickListener() {
            @Override
            public void onClick(View v) {
                NoteBook noteBook = new NoteBook();
                String note_title, note_content;
                note_title = title.getText().toString();
                note_content = content.getText().toString();
                noteBook.Title = note_title;
                noteBook.Content = note_content;
                noteBook.ContentDate = createDate;
                long colum = dbAdapter.insert_note(noteBook);
                if (colum == -1) {
                    Toast toast = Toast.makeText(AddNoteActivity.this, "添加过程错误！！", Toast.LENGTH_SHORT);
                    toast.show();
                } else {
                    Toast toast = Toast.makeText(AddNoteActivity.this, "成功添加数据！！", Toast.LENGTH_SHORT);
                    toast.show();
                    Intent intent = new Intent(AddNoteActivity.this, NoteBookActivity.class);
                    intent.putExtra("name", name);
                    startActivity(intent);
                }
            }


});
    }
}

（二）编辑记事本界面——NoteBookActivity

内容包括添加标题与内容，以及创建时间。

package com.example.jishiben;

import android.content.Intent;
import android.graphics.Color;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.Editable;
import android.text.TextWatcher;
import android.util.Log;
import android.view.View;
import android.view.ViewGroup;
import android.widget.baseAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;

import java.util.ArrayList;

public class NoteBookActivity extends AppCompatActivity {
    private TextView t;
    private Button bt_add, bt_clear;
    private ListView listView;
    private DBAdapter dbAdapter;
    private ArrayList notelist;
    private EditText query;
    NoteBook[] noteBooks;
    baseAdapter mListAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_note_book);
        t = findViewById(R.id.name);
        bt_add = findViewById(R.id.bt_add);
        listView = findViewById(R.id.list_note);
        query = findViewById(R.id.et_query);
        bt_clear = findViewById(R.id.bt_clear);
        Intent intent = this.getIntent();
        final String name = intent.getStringExtra("name");
        t.setText(name + "欢迎你！");
        t.setTextSize(30);
        t.setTextColor(Color.GREEN);
        dbAdapter = new DBAdapter(this);
        dbAdapter.open();
        notelist = new ArrayList<>();
        noteBooks = dbAdapter.queryAllData();
        if (noteBooks == null) {
            listView.setAdapter(null);
        } else {
            for (int i = 0; i < noteBooks.length; i++) {
                notelist.add(noteBooks[i]);
            }
            mListAdapter = new baseAdapter() {
                @Override
                public int getCount() {
                    return notelist.size();
                }

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

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

                @Override
                public View getView(int i, View convertView, ViewGroup parent) {
                    View view;
                    if (convertView == null) {
                        view = View.inflate(getbaseContext(), R.layout.list_item_memo1, null);
                    } else {
                        view = convertView;
                    }
                    NoteBook memo = notelist.get(i);
                    TextView title = (TextView) view.findViewById(R.id.title);
                    TextView content = (TextView) view.findViewById(R.id.content);
                    TextView getsqlId = (TextView) view.findViewById(R.id.getsqlld);
                    TextView createDate = (TextView) view.findViewById(R.id.noticeDate);
                    title.setText(memo.getTitle());
                    content.setText(memo.getContent());
                    createDate.setText(memo.getContentDate());
                    getsqlId.setText(Integer.toString(memo.getID()));
                    return view;
                }
            };
            listView.setAdapter(mListAdapter);
        }
        query.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence s, int start, int count, int after) {

            }

            @Override
            public void onTextChanged(CharSequence charSequence, int start, int before, int count) {
                if (charSequence.toString().equals("")) {
                    bt_clear.setVisibility(View.GONE);
                } else {
                    bt_clear.setVisibility(View.VISIBLE);
                }
                String titleChange = query.getText().toString();
                Log.v("改变数据：", titleChange);
                noteBooks = dbAdapter.queryoneDatafromNote(titleChange);
                notelist.clear();
                for (int j = 0; j < noteBooks.length; j++) {
                    notelist.add(noteBooks[j]);
                }
                mListAdapter.notifyDataSetChanged();
                listView.setAdapter(mListAdapter);
            }

            @Override
            public void afterTextChanged(Editable editable) {

            }
        });
        bt_clear.setonClickListener(new View.onClickListener() {
            @Override
            public void onClick(View v) {
                query.setText("");
            }
        });
        bt_add.setonClickListener(new View.onClickListener() {
            @Override
            public void onClick(View v) {
                Intent intent = new Intent(NoteBookActivity.this, AddNoteActivity.class);
                intent.putExtra("name", name);
                startActivity(intent);
            }
        });
    }
}

（三）定义记事本布局——NoteBook

package com.example.jishiben;

public class NoteBook {
   public int ID = -1;
   public String Title;
   public String Content;
   public String ContentDate;

   public int getID() {
      return ID;
   }

   public void setID(int ID) {
      this.ID = ID;
   }

   public String getTitle() {
      return Title;
   }

   public void setTitle(String title) {
      Title = title;
   }

   public String getContent() {
      return Content;
   }

   public void setContent(String content) {
      Content = content;
   }

   public String getContentDate() {
      return ContentDate;
   }

   public void setContentDate(String contentDate) {
      ContentDate = contentDate;
   }

   @Override
   public String toString(){
      String result = "";
      result += "ID：" + this.ID + "，";
      result += "标题：" + this.Title + "，";
      result += "内容：" + this.Content + "， ";
      result += "日期：" + this.ContentDate + "，";
      return result;
   }
}

（四）连接数据库

package com.example.jishiben;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteException;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteDatabase.CursorFactory;

   public class DBAdapter {

      private static final String DB_NAME = "MyData.db";
      private static final String DB_TABLE1 = "peopleinfo";
        private static final String DB_TABLE2 = "notebook";
      private static final int DB_VERSION = 1;

      public static final String KEY_ID = "_id";
      public static final String KEY_NAME = "name";
      public static final String KEY_PASS = "pass";
      public static final String KEY_SEX = "sex";
      public static final String KEY_MINZU = "minzu";
        public static final String KEY_ID1 = "_id1";
        public static final String KEY_TITLE = "tilte";
        public static final String KEY_ConTENT = "content";
        public static final String KEY_ConTENTDATE = "contentdate";

      private SQLiteDatabase db;
      private final Context context;
      private DBOpenHelper dbOpenHelper;

      public DBAdapter(Context _context) {
         context = _context;
      }

      
      public void close() {
         if (db != null){
            db.close();
            db = null;
         }
      }

      
      public void open() throws SQLiteException {
         dbOpenHelper = new DBOpenHelper(context, DB_NAME, null, DB_VERSION);
         try {
            db = dbOpenHelper.getWritableDatabase();
         }
         catch (SQLiteException ex) {
            db = dbOpenHelper.getReadableDatabase();
         }
      }


      public long insert(People people) {
         ContentValues newValues = new ContentValues();

         newValues.put(KEY_NAME, people.Name);
         newValues.put(KEY_PASS, people.Pass);
         newValues.put(KEY_SEX, people.Sex);
            newValues.put(KEY_MINZU, people.Minzu);
         return db.insert(DB_TABLE1, null, newValues);
      }
        public long insert_note(NoteBook noteBook) {
            ContentValues newValues = new ContentValues();

            newValues.put(KEY_TITLE, noteBook.Title);
            newValues.put(KEY_CONTENT, noteBook.Content);
            newValues.put(KEY_CONTENTDATE, noteBook.ContentDate);

            return db.insert(DB_TABLE2, null, newValues);
        }

      public NoteBook[] queryAllData() {
         Cursor results =  db.query(DB_TABLE2, new String[] { KEY_ID1, KEY_TITLE, KEY_CONTENT, KEY_CONTENTDATE},
               null, null, null, null, null);
         return ConvertToNote(results);
      }

        public People[] queryAllDatafromPeople() {
            Cursor results =  db.query(DB_TABLE1, new String[] { KEY_ID,KEY_NAME, KEY_PASS, KEY_SEX,KEY_MINZU},
                    null, null, null, null, null);
            return ConvertToPeople(results);
        }
        public NoteBook[] queryoneDatafromNote(String name) {
            Cursor results =  db.query(DB_TABLE2, new String[] { KEY_ID1, KEY_TITLE, KEY_CONTENT, KEY_CONTENTDATE},
                    KEY_TITLE + " like '%" + name+"%'", null, null, null, null);
            return ConvertToNote(results);
        }

      public People[] queryoneData(String name) {
         Cursor results =  db.query(DB_TABLE1, new String[] { KEY_ID, KEY_NAME, KEY_PASS, KEY_SEX,KEY_MINZU},
               KEY_NAME + "='" + name+"'", null, null, null, null);
         return ConvertToPeople(results);
      }
        private NoteBook[] ConvertToNote(Cursor cursor){
            int resultCounts = cursor.getCount();
            if (resultCounts == 0 || !cursor.moveToFirst()){
                return null;
            }
            NoteBook[] noteBooks = new NoteBook[resultCounts];
            for (int i = 0 ; i

记事本（一）

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