Android——一個簡單的銀行系統

採用SQLite資料庫進行對資料進行讀取和插入

實現功能：
1：註冊使用者資訊
2：登入介面
3：存錢，取錢，查詢餘額

第一步：先建立一個實體類User
除了對欄位進行set和get還多了Deposit（）Withdraw兩個方法，用於在後面FUNCTION介面進行存錢和取錢
程式碼如下：
public class User {
private String BankName;
private String Name;
private int Money;
private String PassWord;
public User(String Name, String Password, String BankName , int Money) {
super();
this.Name = Name;
this.PassWord = Password;
this.BankName = BankName;
this.Money = Money;
}
public User(){
}
public void setMoney(int Money){
this.Money = Money;
}
public String getName() {
return Name;
}
public String getPassWord() {
return PassWord;
}
public String getBankName() {
return BankName;
}
public int getMoney() {
return Money;
}
//存錢
public void Deposit(int Money) {
this.Money += Money;
}
//取錢
public void Withdraw(int Money) {
if (this.Money < Money) {
Log.d(Dao.TAG, “Withdraw: 餘額不足!”);
return;
} else {
this.Money -= Money;
}
}
public String toString() {
return “[戶主:”+Name+" 銀行型別："+BankName+" 餘額："+Money+"]";
}
}
第二步：
建立一個MyHelper類用於繼承SQLiteOpenHelper類，用於建立資料庫
程式碼如下：
public class MyHelper extends SQLiteOpenHelper {
public static final String TableName = “BankSystem”;
public static final String Name = “Name”;
public static final String PassWord = “PassWord”;
public static final String BankType = “BankType”;
public static final String Money = “Money”;
private static final String DataBase = “BankSystem.db”;
private static final SQLiteDatabase.CursorFactory Factory = null;
public static final int version = 1;
public MyHelper(@Nullable Context context) {
super(context, DataBase, Factory, version);
}
@Override
public void onCreate(SQLiteDatabase db) {
String sql = “create table " + TableName + “( “+Name+” varchar(20) primary key, “+PassWord+” varchar(20),”+BankType+” varchar(20) ,"+Money+" Interget);";
db.execSQL(sql);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("drop table if exists "+TableName);
onCreate(db);
}
}
第三步：
建立登入介面也就是啟動項MainActivity
Drawable 類是對登入介面的兩個圖片進行合適的縮放
MainActivity.java程式碼如下：
public class MainActivity extends AppCompatActivity {
private static EditText editTextUserName;
private static EditText editTextUserPassWord;
private Button btn_Login,btn_Register;
private TextView TitleImage;
public static String name =null;
public static String password = null;
static int i = 0;
private MyHelper myhelper = null ;
private SQLiteDatabase DB;
Dao dao = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

    myhelper = new MyHelper(MainActivity.this);

    editTextUserName = (EditText) findViewById(R.id.userName);
    editTextUserPassWord = (EditText) findViewById(R.id.userPassword);
    btn_Login = (Button) findViewById(R.id.Login);
    btn_Register = (Button) findViewById(R.id.Register);
    TitleImage = (TextView)findViewById(R.id.titleImage);

    Drawable drawableUserName = getResources().getDrawable(R.drawable.user);
    //第一個0是距左邊距離，第二個0是距上邊距離，40分別是長寬
    drawableUserName.setBounds(0, 0, 90, 90);
    editTextUserName.setCompoundDrawables(drawableUserName, null, null, null);
    //****************************
    Drawable drawableUserPassWord = getResources().getDrawable(R.drawable.unlock);
    drawableUserPassWord.setBounds(0, 0, 90, 90);
    editTextUserPassWord.setCompoundDrawables(drawableUserPassWord, null, null, null);
    //****************************
    Drawable drawableTitleImage= getResources().getDrawable(R.drawable.bastard);
    drawableTitleImage.setBounds(0, 0, 100, 90);
    TitleImage.setCompoundDrawables(drawableTitleImage, null, drawableTitleImage, null);
    OnClick onClick = new OnClick();
    btn_Login.setOnClickListener(onClick);
    btn_Register.setOnClickListener(onClick);
}

// public boolean checkAccount(String Name){
// DB=myhelper.getReadableDatabase();
// String query="select * from BankSystem where Name=? ";
// Cursor cursor=DB.rawQuery(query, new String[]{Name});
// if(cursor.moveToNext()){
// cursor.close();
// return true;
// }
// cursor.close();
// return false;
// }

class OnClick implements View.OnClickListener{
@Override
public void onClick(View v) {
Intent intent = null;
dao = new Dao(MainActivity.this);

        name = editTextUserName.getText().toString().trim();
        password = editTextUserPassWord.getText().toString().trim();
        switch (v.getId())
        {
            case R.id.Login:
                if (dao.login(name,password) == true) {
                   Toast.makeText(MainActivity.this,"LOGIN Success",Toast.LENGTH_SHORT).show();
                    intent = new Intent(MainActivity.this, Function.class);
                    break;
                }
                else
                {
                    Toast.makeText(MainActivity.this,"LOGIN Fail",Toast.LENGTH_SHORT).show();
                    break;
                }
            case R.id.Register:
                intent = new Intent(MainActivity.this,Register.class);
                break;
        }
        startActivity(intent);
    }
}

}
activity_main.xml檔案如下
效果圖如下：
前者是對圖片進行了Drawable處理，後面是沒有進行處理

程式碼如下：

<EditText
   android:id="@+id/userName"
   android:layout_width="match_parent"
   android:layout_height="wrap_content"
   android:hint=" Please Entry your BankUserName:"
   android:drawableLeft="@drawable/user"
   android:layout_marginTop="30dp"/>
<EditText
        android:id="@+id/userPassword"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint=" Please Entry your BankUserPassword:"
        android:drawableLeft="@drawable/unlock"
        android:layout_below="@id/userName"
        android:layout_marginTop="20dp"
        android:inputType="textPassword"/>
<LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:orientation="horizontal">
<Button
 android:id="@+id/Login"
 android:layout_width="0dp"
 android:layout_height="wrap_content"
 android:text="Login"
 android:textAllCaps="false"
 android:layout_marginTop="160dp"
 android:layout_weight="1"/>
<Button
        android:id="@+id/Register"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:text="Register"
        android:textAllCaps="false"
        android:layout_marginTop="160dp"
        android:layout_weight="1"/>
</LinearLayout>

第四步建立一個註冊的avtivity命名為Register Register.java程式碼如下： public class Register extends AppCompatActivity { private EditText editTextName,editTextPassWord,editTextEntryPassWord,FirstDeposit,editBankType; private Button btn_Submit; private Spinner spinner; public static String Name = null; public static String PassWord = null; public static String EntryPassWord = null; public static String BankType = null; public static int Money =0; Dao dao =null;

@Override
protected void onCreate(final Bundle savedInstanceState)  {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_register);
    editTextName = (EditText) findViewById(R.id.RegisterBankUserName);
    editTextPassWord = (EditText) findViewById(R.id.RegisterBankPassWord);
    editTextEntryPassWord = (EditText) findViewById(R.id.AgainRegisterBankPassWord);
    FirstDeposit = (EditText) findViewById(R.id.InitDeposit);
    spinner = (Spinner) findViewById(R.id.spinner_BankType);
    btn_Submit = (Button) findViewById(R.id.RegisterSubmitButton);
    
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
        @Override
        public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
            String [] str = getResources().getStringArray(R.array.spinner);
            //點選的事項，選擇的開戶銀行
            BankType = str[position];
        }

        @Override
        public void onNothingSelected(AdapterView<?> parent) {

        }
    });
        btn_Submit.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                dao = new Dao(Register.this);
                Name = editTextName.getText().toString().trim();
                PassWord = editTextPassWord.getText().toString().trim();
                EntryPassWord = editTextEntryPassWord.getText().toString().trim();
                BankType = spinner.getContext().toString().trim();
                try {
                    Money = Integer.parseInt(FirstDeposit.getText().toString().trim());
                }catch (NumberFormatException e)
                {
                    e.printStackTrace();
                }
                if ("".equals(Name) && "".equals(PassWord) && "".equals(EntryPassWord) && "".equals(BankType))
                {
                    Toast.makeText(Register.this,"資訊不能為空，請重試",Toast.LENGTH_SHORT).show();
                    return;
                }
                if (! PassWord.equals(EntryPassWord))
                {
                    Toast.makeText(Register.this,"密碼不一致，請重試",Toast.LENGTH_SHORT).show();
                    return;
                }
                else if ( Money  < 10)
                {
                    Toast.makeText(Register.this,"首次開戶金額不能小於10元，請重試",Toast.LENGTH_SHORT).show();
                    return;
                }
                    dao.Insert(new User(Name,PassWord,BankType,Money));
                    Log.d(Dao.TAG,"success");
                    Intent intent = new Intent(Register.this, Function.class);
                    startActivity(intent);
            }
        });
    }
}
activity_register.xml檔案如下：
activity_register.xml效果圖如下：

activity_register.xml程式碼如下：
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_marginTop="20dp">
<TextView
        android:id="@+id/Title"
        android:layout_width="400dp"
        android:layout_height="30dp"
        android:text="Registration information form"
        android:layout_marginLeft="87dp"
        android:textSize="20sp"
        android:textColor="#000" />
<EditText
        android:id="@+id/RegisterBankUserName"
        android:hint="Please input your name"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:layout_below="@id/Title"/>
<TextView
        android:id="@+id/Sex"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Please choice your sex:"
        android:layout_below="@id/RegisterBankUserName"
        android:layout_marginTop="15dp"/>
<RadioGroup
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
    <RadioButton
            android:id="@+id/sexRadioButtonMale"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="Male"
            android:layout_marginTop="95dp"
            android:layout_marginLeft="155dp"/>
    <RadioButton
            android:id="@+id/sexRadioButtonFemale"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="Female"
            android:layout_marginTop="-31dp"
            android:layout_marginLeft="230dp"/>

</RadioGroup>
<EditText
        android:id="@+id/Age"
        android:hint="Please input your age"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:layout_below="@id/Sex"/>
<EditText
        android:id="@+id/PhoneNumber"
        android:hint="Please input your PhoneNumber"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:layout_below="@id/Age"/>

<EditText
        android:id="@+id/RegisterBankPassWord"
        android:hint="Please input your PassWord"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="5dp"
        android:layout_below="@id/PhoneNumber"/>
<EditText
        android:id="@+id/AgainRegisterBankPassWord"
        android:hint="Please again entry your PassWord"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="10dp"
        android:layout_below="@id/RegisterBankPassWord"/>
<TextView
        android:id="@+id/title"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="15dp"
        android:text="Please choose your bank type："
        android:layout_below="@id/AgainRegisterBankPassWord"/>
<EditText
        android:id="@+id/InitDeposit"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Please input the amount you want to deposit:"
        android:layout_below="@id/title"
        android:textSize="15sp"
        android:layout_marginTop="10dp"/>
<Spinner
        android:id="@+id/spinner_BankType"
        android:layout_width="100dp"
        android:layout_height="wrap_content"
        android:entries="@array/spinner"
        android:layout_gravity="center"
        android:layout_marginTop="347dp"
        android:layout_marginRight="110dp"
        android:layout_alignRight="@id/InitDeposit"/>
<Button
        android:id="@+id/RegisterSubmitButton"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Submit"
        android:layout_below="@id/spinner_BankType"
        android:layout_marginTop="100dp"
        android:textAllCaps="false"
        android:textSize="20sp" />

第五步：建立一個Function活動，用於存錢，取錢，查詢三個功能 Function.java程式碼如下： public class Function extends AppCompatActivity { private Button btn_saveMoney,btn_withdrawMoney,btn_search; Dao dao = new Dao(); User user = null; public static int FUNC_Money = 0;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.function);
    btn_saveMoney = (Button) findViewById(R.id.SaveMoney);
    btn_withdrawMoney = (Button) findViewById(R.id.WithdrawMoney);
    btn_search = (Button) findViewById(R.id.Search);
    OnClick onClick = new OnClick();
    btn_saveMoney.setOnClickListener(onClick);
    btn_withdrawMoney.setOnClickListener(onClick);
    btn_search.setOnClickListener(onClick);
}
class OnClick implements View.OnClickListener
{

    @Override
    public void onClick(View v) {
        String Name = Register.Name;
        String Password = Register.PassWord;
        String BankType = Register.BankType;
        int Money = Register.Money;
        user = new User(Name,Password,BankType,Money);
        switch (v.getId()){
            case R.id.SaveMoney:
                AlertDialog.Builder dialogSaveMoney = new AlertDialog.Builder(Function.this);
                View viewSaveMoney = LayoutInflater.from(Function.this).inflate(R.layout.activity_save_money,null);
                TextView textViewSaveMoney = viewSaveMoney.findViewById(R.id.SaveMoneyTextView);
                final EditText editTextSaveMoney = viewSaveMoney.findViewById(R.id.SaveMoneyEditText);
                Button submitSaveMoney = viewSaveMoney.findViewById(R.id.SaveMoneyButton);
                submitSaveMoney.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        try {
                            FUNC_Money = Integer.parseInt(editTextSaveMoney.getText().toString());
                        }catch (NumberFormatException e)
                        {
                            e.printStackTrace();
                        }
                        String Name = Register.Name;
                        int Money = dao.Query(Name);
                        user.setMoney(Money);
                        user.Deposit(FUNC_Money);
                        dao.Update(Name,user.getMoney());
                        Toast.makeText(Function.this,"當前賬戶餘額為"+ user.getMoney(),Toast.LENGTH_SHORT).show();

                    }
                    public void onClick(DialogInterface dialog, int which, boolean isChecked){
                        dialog.dismiss();
                    }
                });
                dialogSaveMoney.setTitle("Little Bastard Bank").setIcon(R.drawable.bastard).setView(viewSaveMoney).show();
                break;
            case R.id.WithdrawMoney:
                AlertDialog.Builder dialogWithdraw = new AlertDialog.Builder(Function.this);
                View viewWithdrawMoney = LayoutInflater.from(Function.this).inflate(R.layout.activity_withdraw_money,null);
                TextView textViewWithdrawMoney = viewWithdrawMoney.findViewById(R.id.WithdrawMoneyTextView);
                final EditText editTextWithdrawMoney = viewWithdrawMoney.findViewById(R.id.WithdrawMoneyEditText);
                Button buttonWithdrawMoney = viewWithdrawMoney.findViewById(R.id.WithdrawMoneyButton);
                buttonWithdrawMoney.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        try {
                            FUNC_Money = Integer.parseInt(editTextWithdrawMoney.getText().toString());
                        }catch (NumberFormatException e)
                        {
                            e.printStackTrace();
                        }
                        String Name = Register.Name;
                        int Money = dao.Query(Name);
                        user.setMoney(Money);
                        user.Withdraw(FUNC_Money);
                        dao.Update(Name,user.getMoney());
                        Toast.makeText(Function.this,"當前賬戶餘額為"+ user.getMoney(),Toast.LENGTH_SHORT).show();

                    }
                    public void onClick(DialogInterface dialog, int which, boolean isChecked){
                        dialog.dismiss();
                    }
                });
                dialogWithdraw.setTitle("Little Bastard Bank").setIcon(R.drawable.bastard).setView(viewWithdrawMoney).show();
                break;
            case R.id.Search:
                AlertDialog.Builder dialogSearch = new AlertDialog.Builder(Function.this);
                View viewSearch = LayoutInflater.from(Function.this).inflate(R.layout.activity_search,null);
                TextView textViewSearch = viewSearch.findViewById(R.id.SearchTextView);
                final TextView textViewSearchHint = viewSearch.findViewById(R.id.SearchTextViewHint);
                Button buttonSearch = viewSearch.findViewById(R.id.SearchButton);
                buttonSearch.setOnClickListener(new View.OnClickListener() {
                    @Override
                    public void onClick(View v) {
                        String Name = Register.Name;
                        int EXE_Money = dao.Query(Name);
                        Toast.makeText(Function.this,"當前賬戶餘額為"+ EXE_Money,Toast.LENGTH_SHORT).show();
                    }
                });
                dialogSearch.setTitle("Little Bastard Bank").setIcon(R.drawable.bastard).setView(viewSearch).show();
                break;
        }
    }
}

}
activity_function.xml檔案如下
activity_function.xml效果圖如下：

activity_function.xml程式碼如下：

/*********************************************執行效果圖演示***************************************/
首先得註冊才能登入，或者使用資料庫中的使用者資訊登入都可以
![在這裡插入圖片描述](https://img-blog.csdnimg.cn/20210205160847366.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L05ld3M1MzIzMTMyMw==,size_16,color_FFFFFF,t_70#pic_center)

註冊介面，未填寫資訊前

填寫完資訊之後

點選submit按鈕跳轉到Function介面

隨意點一個然後進行操作
我們先點存錢，介面如下：

在我們註冊使用者時存入的金額是10元（開戶最少存入金額10元），在這裡我們存1塊進去，底部會用Toast顯示11塊
//注意看底部Toast
//注意看底部Toast
//注意看底部Toast

然後我們點選取錢，介面如下:

由於之前存入一塊，我們的賬戶現在剩餘11元，然後在取出2元，賬戶剩餘9元
//注意看底部Toast
//注意看底部Toast
//注意看底部Toast

然後點選查詢按鈕，會顯示9元
//注意看底部Toast
//注意看底部Toast
//注意看底部Toast

記得在values中建立檔案用於Spinner下拉列表中可供選擇的值，不然就會出現上面那個錯誤，找不到選擇的值