android studio简单的密码日记本，实现增删改查功能
简单的记事本
软件名字：一本日记
软件功能 ：简单的密码日记本，实现增删改查功能
软件的使用知识点：
布局方面：线性布局，相对布局
控件方面：常见控件,List View, Navigation View(滑动菜单),FloatingActionButton （悬浮按钮）
后台方面：主要是Adapter和Sq Lite,Intent
项目的结构如下图：
[外链图片转存失败(img-OocaH9L5-1563628277567)(C:\Users\weng\Desktop\安卓期末1.png)]
分析软件的组成：
展示核心的代码
1，登录
2注册
注册的业务逻辑：
public class RegistActivity extends AppCompatActivity {
private EditText edt_setname;
private EditText edt_setpassword;
private EditText edt_confirm_password;
private Button btn_register;
String name,password,id;
private MyDB myDB;
ContentValues contentValues=new ContentValues();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);//隐藏状态栏
getSupportActionBar().hide();//隐藏标题栏*/
setContentView(R.layout.activity_regist);
initUI();
myDB=new MyDB(this);
btn_register.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
SQLiteDatabase db=myDB.getWritableDatabase();
name = edt_setname.getText().toString();
password = edt_setpassword.getText().toString();
if (edt_setname.getText().toString().contains(" ") || edt_setpassword.getText().toString().contains(" ")) {
Toast.makeText(RegistActivity.this, "输入的用户名或密码不能包含空格", Toast.LENGTH_SHORT).show();
return;
}
else if(edt_setpassword.getText().toString().length()==0||edt_setname.getText().toString().length()==0){
Toast.makeText(RegistActivity.this, "请输入用户名或密码", Toast.LENGTH_SHORT).show();
return;
}
else if(!edt_confirm_password.getText().toString().equals(edt_setpassword.getText().toString())){
Toast.makeText(RegistActivity.this, "两次密码不一致，请确认再注册", Toast.LENGTH_SHORT).show();
return;
}
if(login(name)){
Toast.makeText(RegistActivity.this, "该用户名已注册", Toast.LENGTH_SHORT).show();
return;
}
contentValues.put("username", name);
contentValues.put("password", password);
db.insert("tb_user", null, contentValues);
String sql="select user_id from tb_user where username=? and password=?";
Cursor cursor = db.rawQuery(sql, new String[] {name, password});
if(cursor.moveToNext()){//id
id=Integer.toString(cursor.getInt(0));//防止数据库的值null和0 分不清
}
cursor.close();
db.close();
Toast.makeText(RegistActivity.this, "注册成功", Toast.LENGTH_SHORT).show();
new Thread(){
@Override
public void run() {
super.run();
try {
Thread.sleep(1000);
Intent intent = new Intent(RegistActivity.this,LoginActivity.class);
intent.putExtra("name",edt_setname.getText().toString());
intent.putExtra("password",edt_setpassword.getText().toString());
setResult(1, intent);//返回页面1
finish();
// startActivity(intent);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}.start();
}
});
}
/**
* 初始化View :initUI()
*/
public void initUI(){
edt_setname=(EditText)findViewById(R.id.edt_setusername);
edt_setpassword=(EditText)findViewById(R.id.edt_setpassword);
edt_confirm_password=(EditText)findViewById(R.id.edt_confirm_password);
btn_register=(Button)findViewById(R.id.btn_register);
}
/**
* 查询数据库是否有重复的
* 进行数据的查询 login()
*/
public boolean login(String name){
SQLiteDatabase db=myDB.getWritableDatabase();
String sql="select * from tb_user where username=?";
Cursor cursor=db.rawQuery(sql,new String[]{name});
if (cursor.getCount()!=0){
cursor.close();
return true;
}
return false;
}
}
3主页面
<ListView
android:id="@+id/list"
android:layout_width="match_parent"
android:layout_height="wrap_content"
>
ListView>
<android.support.design.widget.FloatingActionButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentRight="true"
android:layout_marginBottom="30dp"
android:layout_marginRight="20dp"
app:fabSize="mini"
app:srcCompat="@android:drawable/ic_input_add"
android:id="@+id/floactAdd"
app:backgroundTint="@color/colorPrimaryDark" />
RelativeLayout>
<android.support.design.widget.NavigationView
android:layout_gravity="left"
app:headerLayout="@layout/head"
app:menu="@menu/meun_main"
android:id="@+id/navigat"
android:layout_width="230dp"
android:layout_height="match_parent"/>
主页面的业务逻辑:
public class IndexActivity extends AppCompatActivity {
List<Note> mList;
private FloatingActionButton fdb;
private NavigationView navigationView;
private ListView listView;
private MyAdapter myAdapter;
private MyDB myDB;
private Cursor cursor;
private SQLiteDatabase dbreader;;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);//隐藏状态栏
getSupportActionBar().hide();//隐藏标题栏
setContentView(R.layout.activity_test);
listView = (ListView) findViewById(R.id.list);
navigationView = (NavigationView) findViewById(R.id.navigat);
View view1 = navigationView.getHeaderView(0);//通过nav来查询head文件
TextView wc = view1.findViewById(R.id.welcome);
myDB = new MyDB(this);
dbreader = myDB.getReadableDatabase();
wc.setText("欢迎你:" + LoginActivity.username);
Toast.makeText(IndexActivity.this, "登录成功，欢迎回来！", Toast.LENGTH_SHORT).show();
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int position, long id) {
Intent intent = new Intent(IndexActivity.this, showActivity.class);
intent.putExtra("ID", mList.get(position).getId());
intent.putExtra("content", mList.get(position).getContent());
intent.putExtra("time", mList.get(position).getTime());
startActivity(intent);
}
});
fdb = (FloatingActionButton) findViewById(R.id.floactAdd);
fdb.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent intent = new Intent(IndexActivity.this, AddContentActivity.class);
startActivity(intent);
}
});
navigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {
@Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {
switch (item.getItemId()){
case R.id.prsetposs:
Intent intent1=new Intent(IndexActivity.this,setpasswordActivity.class);
intent1.putExtra("username",LoginActivity.username);
startActivity(intent1);
break;
case R.id.showtime:
Toast.makeText(IndexActivity.this,AddContentActivity.getTime(),Toast.LENGTH_LONG).show();
break;
case R.id.prsize:
Toast.makeText(IndexActivity.this,IndexActivity.this.allDBNum() + "个用户使用了软件",Toast.LENGTH_LONG).show();
break;
case R.id.success:
Intent intent=new Intent(IndexActivity.this,LoginActivity.class);
Toast.makeText(IndexActivity.this,"退出成功",Toast.LENGTH_LONG).show();
startActivity(intent);
}
return true;
}
});
}
public void selectDb() {
mList = new ArrayList<>();
cursor = dbreader.rawQuery("SELECT * FROM tb_note WHERE userID = ?", new String[]{LoginActivity.userID + ""});
while (cursor.moveToNext()) {
Note note = new Note();
int id = cursor.getInt(cursor.getColumnIndex("ID"));
String time = cursor.getString(cursor.getColumnIndex("time"));
String content = cursor.getString(cursor.getColumnIndex("content"));
note.setTime(time);
note.setContent(content);
note.setId(id);
mList.add(note);
}
cursor.close();
myAdapter = new MyAdapter(this, mList);
listView.setAdapter(myAdapter);
}
@Override
protected void onResume() {
super.onResume();
selectDb();
}
/**
*查询用户的个数 allDBNum()
*/
public int allDBNum( ){
String sql = "select count(*) count from tb_user";
Cursor cursor = dbreader.rawQuery(sql, null);
cursor.moveToFirst();
int count= cursor.getInt(0);
if (cursor.getCount()!=0){
cursor.close();
}
return count;
}
}
4 List View 布局：
<LinearLayout
android:layout_width="match_parent"
android:layout_height="50dp"
android:layout_gravity="center_vertical"
android:orientation="vertical">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/list_content"
android:textColor="#000"
android:textSize="20sp"
android:text="tv"/>
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/list_time"
android:textColor="#000"
android:textSize="20sp"
android:text="time"/>
LinearLayout>
5List View适配器:
public class MyAdapter extends BaseAdapter {
private Context mContext;
private List<Note> mList;
private LinearLayout mlayout;
public MyAdapter(Context mContext, List<Note> mList){
this.mContext=mContext;
this.mList=mList;
}
@Override
public int getCount() {
return mList.size();
}
@Override
public Object getItem(int position) {
return mList.get(position);
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = LayoutInflater.from(mContext);
mlayout=(LinearLayout) inflater.inflate(R.layout.listre,null);
TextView content=(TextView)mlayout.findViewById(R.id.list_content);
TextView time=(TextView)mlayout.findViewById(R.id.list_time);
content.setText(mList.get(position).getContent());
time.setText(mList.get(position).getTime());
return mlayout;
}
}
6数据库文件:
ublic class MyDB extends SQLiteOpenHelper{
//用户表
public static final String CREATE_USER="create table tb_user(" +
"user_id integer primary key autoincrement," +
"username varchar(50)," +
"password varchar(50))";
//
public static final String CREATE_NOTE="create table tb_note("+
"ID integer primary key AUTOINCREMENT,"+
"content TEXT NOT NULL,"+
"userID integer,"+
"time TEXT NOT NULL)";
//上下文
private Context mcontext;
public static final String CREATE_NOTES="";
public MyDB(Context context) {
super(context, "MyDB.db", null, 2);
mcontext=context;
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(CREATE_USER);
db.execSQL(CREATE_NOTE);
Toast.makeText(mcontext,"创建成功！",Toast.LENGTH_SHORT).show();
}
@Override
public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {
}
}
7Note的实体类：
public class Note {
private Integer id;
private Integer userID;
private String content;
private String time;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public Integer getUserID() {
return userID;
}
public void setUserID(Integer userID) {
this.userID = userID;
}
public String getContent() {
return content;
}
public void setContent(String content) {
this.content = content;
}
public String getTime() {
return time;
}
public void setTime(String time) {
this.time = time;
}
}
8添加内容的页面：
<EditText
android:id="@+id/text"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight="1"
android:gravity="top"
android:hint="开始记录吧"/>
<Button
android:id="@+id/save"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="保存"
android:onClick="save"/>
<Button
android:id="@+id/cancle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="取消"
android:onClick="cancle"/>
添加内容的业务逻辑：
private EditText met;
private MyDB myDB;
private SQLiteDatabase mysqldb;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);//隐藏状态栏
getSupportActionBar().hide();//隐藏标题栏
setContentView(R.layout.activity_add_content);
met=(EditText)findViewById(R.id.text);
myDB=new MyDB(this);
mysqldb=myDB.getWritableDatabase();
}
public void save(View v) {
DdAdd();
finish();
}
public void cancle(View v) {
met.setText("");
finish();
}
public void DdAdd(){
ContentValues cv = new ContentValues();
cv.put("content",met.getText().toString());
cv.put("time",getTime());
cv.put("userID", LoginActivity.userID);
mysqldb.insert("tb_note",null,cv);//插入数据
}
public static String getTime(){
SimpleDateFormat sdf=new SimpleDateFormat("yyyy年MM月dd日 HH:mm:ss");
Date date=new Date();
String str=sdf.format(date);
return str;
}
9显示内容的页面：
<TextView
android:id="@+id/showtime"
android:layout_width="match_parent"
android:layout_height="30dp"
android:layout_marginLeft="10dp"
android:textSize="20sp"/>
<EditText
android:id="@+id/showtext"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:textSize="20sp"
android:gravity="top"
android:layout_weight="1"
android:layout_marginTop="10dp"
android:layout_marginLeft="10dp"
android:textColor="#000"
android:hint="记事本"/>
<Button
android:id="@+id/delete"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="删除"
android:onClick="delete"/>
<Button
android:id="@+id/update"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="修改"
android:onClick="update" />
<Button
android:id="@+id/back"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="返回"
android:onClick="goBack"/>
LinearLayout>
显示页面的业务逻辑：
public class showActivity extends AppCompatActivity {
private EditText mtext;
private TextView time;
private MyDB myDB;
private SQLiteDatabase msql;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);//隐藏状态栏
getSupportActionBar().hide();//隐藏标题栏
setContentView(R.layout.activity_show);
mtext=(EditText) findViewById(R.id.showtext);
time=(TextView)findViewById(R.id.showtime);
myDB=new MyDB(this);
msql=myDB.getWritableDatabase();
mtext.setInputType(InputType.TYPE_CLASS_TEXT);//开启可以编写
mtext.setText(getIntent().getStringExtra("content"));
time.setText(getIntent().getStringExtra("time"));
}
/**
* 删除 delete
* @param v
*/
public void delete(View v) {
int id = getIntent().getIntExtra("ID",0);
msql.delete("tb_note","ID = " + id,null);
finish();
/**
* 修改 update
*/
}public void update(View v){
int id = getIntent().getIntExtra("ID",0);
String content=mtext.getText().toString();
msql.execSQL("UPDATE tb_note SET content=? WHERE ID = ?",
new String[]{content,id+""});
finish();
}
/**
* 关闭
* @param v
*/
public void goBack(View v) {
finish();
}
}
10修改密码的页面：
<TextView
android:layout_marginTop="-120dp"
android:text="修改密码"
android:textSize="34dp"
android:layout_marginBottom="20dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<EditText
android:id="@+id/setpass"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:hint="输入新密码"
/>
<Button
android:id="@+id/yes"
android:text="确定"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:onClick="yes"/>
<Button
android:id="@+id/no"
android:text="取消"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:onClick="no"/>
LinearLayout>
修改密码的业务逻辑：
public class setpasswordActivity extends AppCompatActivity {
private EditText setpass;
private MyDB myDB;
private SQLiteDatabase msql;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);//隐藏状态栏
getSupportActionBar().hide();
setContentView(R.layout.activity_setpassword);
myDB=new MyDB(this);
msql=myDB.getWritableDatabase();
setpass=(EditText)findViewById(R.id.setpass);
}
public void yes(View v){
String username = getIntent().getStringExtra("username");
String pass=setpass.getText().toString();
msql.execSQL("UPDATE tb_user SET password=? WHERE username=?",
new String[]{pass,username});
Toast.makeText(setpasswordActivity.this, "密码修改完了，请记住现在的密码", Toast.LENGTH_SHORT).show();
Intent intent2=new Intent(setpasswordActivity.this,LoginActivity.class);
startActivity(intent2);
finish();
}
public void no(View v){
Intent intent=new Intent(setpasswordActivity.this,IndexActivity.class);
startActivity(intent);
finish();
}
}
软件的展示图片：
登录：
注册：
主页面
主页面2
添加
修改
