Android實現記賬本（麻雀雖小，五臟俱全）
阿新 • • 發佈：2018-11-28
1、在androidstudio上新建一個basic專案
2、在系統自動建立的content_main.xml檔案中新增listview，程式碼如下：
<ListView
android:id="@+id/lv_main"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />3、編寫listview介面卡，這裡把程式碼貼出，不再一一介紹，程式碼如下：
public class CostListAdapter extends BaseAdapter { private List<CostBean> mList; private Context mContext; private LayoutInflater mLayoutInflater; public CostListAdapter(Context context, List<CostBean> list){ mContext=context; mList=list; mLayoutInflater=LayoutInflater.from(context); } @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) { ViewHolder viewHolder; if (convertView==null){ viewHolder=new ViewHolder(); convertView=mLayoutInflater.inflate(R.layout.list_item,null); viewHolder.mTvCostTitle= (TextView) convertView.findViewById(R.id.tv_title); viewHolder.mTvCostDate= (TextView) convertView.findViewById(R.id.tv_date); viewHolder.mTvCostMoney= (TextView) convertView.findViewById(R.id.tv_cost); convertView.setTag(viewHolder); }else { viewHolder= (ViewHolder) convertView.getTag(); } CostBean bean=mList.get(position); viewHolder.mTvCostTitle.setText(bean.costTitle); viewHolder.mTvCostDate.setText(bean.costDate); viewHolder.mTvCostMoney.setText(bean.costMoney); return convertView; } private static class ViewHolder{ public TextView mTvCostTitle; public TextView mTvCostDate; public TextView mTvCostMoney; } }
這裡再給出list_item的佈局程式碼如下：
<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="match_parent" android:layout_height="80dp"> <TextView android:id="@+id/tv_title" android:layout_width="150dp" android:layout_height="80dp" android:layout_marginLeft="10dp" android:layout_alignParentLeft="true" android:singleLine="true" android:ellipsize="marquee" android:textSize="35sp" android:gravity="center" android:text="costTitle"/> <TextView android:id="@+id/tv_date" android:layout_width="wrap_content" android:layout_height="80dp" android:gravity="center" android:textSize="20sp" android:layout_marginLeft="15dp" android:layout_toRightOf="@+id/tv_title" android:text="costDate"/> <TextView android:id="@+id/tv_cost" android:layout_width="wrap_content" android:layout_height="80dp" android:gravity="center" android:layout_alignParentRight="true" android:textSize="30sp" android:layout_marginRight="20dp" android:text="30"/> </RelativeLayout>
4、測試介面卡是否正常（經過執行除錯，正常）。
5、新建實體Bean物件，程式碼如下：
public class CostBean implements Serializable {
public String costTitle;
public String costDate;
public String costMoney;
}這裡implements的意義是為了一會的intent傳遞。
6、新建資料庫，並完成簡單的增刪改查業務，程式碼如下：
public class DatabaseHelper extends SQLiteOpenHelper { public static final String COST_DATE = "cost_date"; public static final String COST_TITLE = "cost_title"; public static final String COST_MONEY = "cost_money"; public static final String COST = "cost"; public DatabaseHelper(Context context) { super(context, "daily", null, 1); } @Override public void onCreate(SQLiteDatabase db) { db.execSQL("create table if not exists cost("+ "id integer primary key, "+ "cost_title varchar, "+ "cost_date varchar, "+ "cost_money varchar)"); } public void insertCost(CostBean costBean){ SQLiteDatabase database=getWritableDatabase(); ContentValues cv=new ContentValues(); cv.put(COST_TITLE,costBean.costTitle); cv.put(COST_DATE,costBean.costDate); cv.put(COST_MONEY,costBean.costMoney); database.insert(COST,null,cv); } public void deleteAllData(){ SQLiteDatabase database=getWritableDatabase(); database.delete(COST,null,null); } public Cursor getAllCostData(){ SQLiteDatabase database=getWritableDatabase(); return database.query(COST,null,null,null,null,null,COST_DATE + " ASC"); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { } }
這裡新建了一個“daily”的資料庫和“cost”表，並寫了簡單的增加、刪除和查詢資料的功能。
7、在這裡給大家推薦一個檢視SQLite資料庫比較好用的工具---SQLiteStudio，具體使用方法給大家放一個連線，裡面講的非常清楚：https://blog.csdn.net/Monly_jiajia/article/details/58621469
8、我先把MainActivity的程式碼放在這兒，然後再跟大家解釋。程式碼如下：
public class MainActivity extends AppCompatActivity {
private List<CostBean> mCostBeenList;
private DatabaseHelper mDatabaseHelper;
private CostListAdapter mAdapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
mDatabaseHelper=new DatabaseHelper(this);
mCostBeenList=new ArrayList<>();
initCostData();
ListView costList= (ListView) findViewById(R.id.lv_main);
mAdapter=new CostListAdapter(this,mCostBeenList);
costList.setAdapter(mAdapter);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
AlertDialog.Builder builder=new AlertDialog.Builder(MainActivity.this);
LayoutInflater inflater=LayoutInflater.from(MainActivity.this);
View viewDialog=inflater.inflate(R.layout.new_cost_data,null);
final EditText title= (EditText) viewDialog.findViewById(R.id.et_cost_title);
final EditText money= (EditText) viewDialog.findViewById(R.id.et_cost_money);
final DatePicker date= (DatePicker) viewDialog.findViewById(R.id.dp_cost_date);
builder.setView(viewDialog);
builder.setTitle("新的花費");
builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
CostBean coseBean=new CostBean();
coseBean.costTitle=title.getText().toString();
coseBean.costMoney=money.getText().toString();
coseBean.costDate=date.getYear()+"-"+(date.getMonth()+1)+"-"+date.getDayOfMonth();
mDatabaseHelper.insertCost(coseBean);
mCostBeenList.add(coseBean);
mAdapter.notifyDataSetChanged();
}
});
builder.setNegativeButton("Cancel",null);
//勿忘！！！
builder.create().show();
}
});
//開啟SQLiteStudio
SQLiteStudioService.instance().start(this);
}
private void initCostData() {
Cursor cursor= mDatabaseHelper.getAllCostData();
if (cursor!=null){
while (cursor.moveToNext()){
CostBean costBean=new CostBean();
costBean.costTitle=cursor.getString(cursor.getColumnIndex("cost_title"));
costBean.costDate=cursor.getString(cursor.getColumnIndex("cost_date"));
costBean.costMoney=cursor.getString(cursor.getColumnIndex("cost_money"));
mCostBeenList.add(costBean);
}
cursor.close();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.action_chart) {
// Intent intent=new Intent(MainActivity.this,ChartActivity.class);
// intent.putExtra("cost_list", (Serializable) mCostBeenList);
// startActivity(intent);
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
protected void onDestroy() {
SQLiteStudioService.instance().stop();
super.onDestroy();
}
}程式碼大家仔細一讀也就會懂，最主要的內容是我們點選一個FloatingActionButton時可以新記一筆賬單，這裡使用AlertDialog實現，下面再貼出AlertDialog的view new_cost_data的xml佈局程式碼：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:gravity="center"
android:layout_height="match_parent">
<EditText
android:id="@+id/et_cost_title"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="4dp"
android:hint="Cost Title"/>
<EditText
android:id="@+id/et_cost_money"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="4dp"
android:hint="Cost Money"/>
<DatePicker
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="4dp"
android:id="@+id/dp_cost_date"
android:datePickerMode="spinner"
android:calendarViewShown="false"/>
</LinearLayout>需要注意的是，在執行插入（或其他方式）資料到資料庫時，我們也一塊把資料加入到了CostBean裡面（使用一開始定義好的mCostBeanList）,另外也要注意，在對資料的操作完成後，記得使用adapter更新資料！即：
mAdapter.notifyDataSetChanged();
關於Android記賬本暫時跟大家分享到這兒，其實還可以在這個專案的基礎上再加許多東西。