{"id":58560,"date":"2024-10-12T20:48:15","date_gmt":"2024-10-12T12:48:15","guid":{"rendered":"https:\/\/server.hk\/cnblog\/58560\/"},"modified":"2024-10-12T20:48:15","modified_gmt":"2024-10-12T12:48:15","slug":"android%e6%95%b8%e6%93%9a%e5%ba%ab%e4%b8%ad%e5%a6%82%e4%bd%95%e4%bd%bf%e7%94%a8sum%e5%87%bd%e6%95%b8%e5%af%a6%e7%8f%be%e6%95%b8%e6%93%9a%e6%b1%82%e5%92%8c-android%e6%95%b8%e6%93%9a%e5%ba%absum","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/58560\/","title":{"rendered":"Android\u6578\u64da\u5eab\u4e2d\u5982\u4f55\u4f7f\u7528SUM\u51fd\u6578\u5be6\u73fe\u6578\u64da\u6c42\u548c (android\u6578\u64da\u5eabsum)"},"content":{"rendered":"<h1 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{\n        String createTable = \"CREATE TABLE sales (id INTEGER PRIMARY KEY, amount REAL)\";\n        db.execSQL(createTable);\n    }\n\n    @Override\n    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {\n        db.execSQL(\"DROP TABLE IF EXISTS sales\");\n        onCreate(db);\n    }\n}<\/code><\/pre>\n<h3 id=\"2-%e6%8f%92%e5%85%a5%e6%95%b8%e6%93%9a-TbCHvrynEI\">2. \u63d2\u5165\u6578\u64da<\/h3>\n<p>\u5728\u5275\u5efa\u597d\u8868\u683c\u5f8c\uff0c\u6211\u5011\u9700\u8981\u63d2\u5165\u4e00\u4e9b\u6578\u64da\u4ee5\u4fbf\u9032\u884c\u6c42\u548c\u64cd\u4f5c\u3002<\/p>\n<pre><code>public void insertSale(float amount) {\n    SQLiteDatabase db = this.getWritableDatabase();\n    ContentValues values = new ContentValues();\n    values.put(\"amount\", amount);\n    db.insert(\"sales\", null, values);\n    db.close();\n}<\/code><\/pre>\n<h3 id=\"3-%e4%bd%bf%e7%94%a8sum%e5%87%bd%e6%95%b8%e6%9f%a5%e8%a9%a2%e6%95%b8%e6%93%9a-TbCHvrynEI\">3. 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id=\"%e7%a4%ba%e4%be%8b%ef%bc%9a%e5%ae%8c%e6%95%b4%e7%9a%84%e4%bd%bf%e7%94%a8%e6%b5%81%e7%a8%8b-TbCHvrynEI\">\u793a\u4f8b\uff1a\u5b8c\u6574\u7684\u4f7f\u7528\u6d41\u7a0b<\/h2>\n<p>\u4ee5\u4e0b\u662f\u4e00\u500b\u5b8c\u6574\u7684\u793a\u4f8b\uff0c\u5c55\u793a\u5982\u4f55\u5728Android\u61c9\u7528\u4e2d\u4f7f\u7528SUM\u51fd\u6578\u4f86\u8a08\u7b97\u92b7\u552e\u7e3d\u984d\u3002<\/p>\n<pre><code>public class MainActivity extends AppCompatActivity {\n    DatabaseHelper dbHelper;\n\n    @Override\n    protected void onCreate(Bundle savedInstanceState) {\n        super.onCreate(savedInstanceState);\n        setContentView(R.layout.activity_main);\n\n        dbHelper = new DatabaseHelper(this);\n        dbHelper.insertSale(100.0f);\n        dbHelper.insertSale(200.0f);\n        dbHelper.insertSale(150.0f);\n\n        float totalSales = dbHelper.getTotalSales();\n        Log.d(\"Total Sales\", \"Total Sales Amount: \" + totalSales);\n    }\n}<\/code><\/pre>\n<h2 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