BeFZdL0w

1package ting.a1203_2;
2
3import android.database.Cursor;
4import android.database.SQLException;
5import android.database.sqlite.SQLiteDatabase;
6import android.support.v7.app.AppCompatActivity;
7import android.os.Bundle;
8import android.view.View;
9import android.widget.AdapterView;
10import android.widget.Button;
11import android.widget.EditText;
12import android.widget.ListView;
13import android.widget.SimpleCursorAdapter;
14import android.widget.Toast;
15
16import static android.R.attr.id;
17
18public class MainActivity extends AppCompatActivity {
19    private SQLiteDatabase db = null;
20    private final static String CREATE_TABLE = "CREATE TABLE IF NOT EXISTS table02(_id INTEGER PRIMARY KEY, name TEXT, price INTEGER)";
21
22    ListView lv1;
23    Button btnSearchData, btnSearchAll;
24    EditText etID;
25    Cursor cursor;
26
27
28    @Override
29    protected void onCreate(Bundle savedInstanceState) {
30        super.onCreate(savedInstanceState);
31        setContentView(R.layout.activity_main);
32
33        lv1 = (ListView) findViewById(R.id.lv1);
34        btnSearchData = (Button) findViewById(R.id.btnSearchData);
35        btnSearchAll = (Button) findViewById(R.id.btnSearchAll);
36        etID = (EditText) findViewById(R.id.etID);
37
38        btnSearchData.setOnClickListener(myListener);
39        btnSearchAll.setOnClickListener(myListener);
40        lv1.setOnItemClickListener(lv1Listener);
41
42        db = openOrCreateDatabase("db02.db", MODE_PRIVATE, null); // 建立或開啟資料庫db02.db
43        // 新增資料表 插入資料
44        try {
45            db.execSQL(CREATE_TABLE);
46            db.execSQL("INSERT INTO table02 (name, price) values ('Macbook Air', 33234)");
47            db.execSQL("INSERT INTO table02 (name, price) values ('ASUS', 15000)");
48            db.execSQL("INSERT INTO table02 (name, price) values ('msi', 40000)");
49            db.execSQL("INSERT INTO table02 (name, price) values ('lenovo', 50000)");
50        } catch (Exception e) {}
51
52        // 預設顯示全部
53        cursor = getAll();
54        UpdateAdapter(cursor);
55    }
56
57    private ListView.OnItemClickListener lv1Listener = new ListView.OnItemClickListener() {
58        @Override
59        public void onItemClick(AdapterView<?> adapterView, View view, int position, long l) {
60            cursor.moveToPosition(position);
61            Cursor c = get(id);
62            String s = "id= " + id + "\r\n" + "name=" + c.getString(1) + "\r\n" + "price=" + c.getInt(2);
63            Toast.makeText(getApplicationContext(), s, Toast.LENGTH_LONG).show();
64        }
65    };
66
67
68    @Override
69    protected void onDestroy() {
70        super.onDestroy();
71        db.close();
72    }
73
74    private Button.OnClickListener myListener = new Button.OnClickListener() {
75        @Override
76        public void onClick(View view) {
77            try {
78                switch (view.getId()) {
79                    case R.id.btnSearchData:
80                    {
81                        long id = Integer.parseInt(etID.getText().toString());
82                        cursor = get(id);
83                        UpdateAdapter(cursor);
84                        break;
85                    }
86                    case R.id.btnSearchAll:
87                    {
88                        cursor = getAll();
89                        UpdateAdapter(cursor);
90                        break;
91                    }
92                }
93            } catch (Exception err) {
94                Toast.makeText(getApplicationContext(), "查無此資料！", Toast.LENGTH_LONG).show();
95            }
96        }
97    };
98
99    private void UpdateAdapter(Cursor cursor) {
100        if (cursor != null && cursor.getCount() >= 0) {
101            SimpleCursorAdapter adapter = new SimpleCursorAdapter(this, R.layout.mylayout ,
102                    cursor, new String[]{"_id", "name" , "price"},
103                    new int[] {R.id.txt, R.id.txtName, R.id.txtPrice}, 0);
104
105            // SimpleCursorAdapter 負責橋接顯示界面元件ListView與Cursor
106            // 參數1: 本應用程式
107            // 參數2: 顯示的介面元件配置資源黨
108            // 參數3: cursor為要顯示的資料
109            // 參數4: 要顯示的欄位，_id , name, price
110            // 參數5: 以自訂的myLayout 顯示界面元件對應的欄位
111            // 參數6: 代表flag(旗標)，自Android 4.X版後設定為0，可取得更好地執行效率。
112            lv1.setAdapter(adapter);
113        }
114    }
115
116    public Cursor getAll(){
117        Cursor cursor = db.rawQuery("SELECT _id , name , price FROM table02" , null);
118        return cursor;
119    }
120
121    public Cursor get(long rowId)throws SQLException{
122        Cursor cursor = db.rawQuery("SELECT _id , name , price FROM table02 WHERE _id = " + rowId , null);
123        if(cursor.getCount()>=0)
124            cursor.moveToFirst();
125        else
126            Toast.makeText(getApplicationContext(), "No data" , Toast.LENGTH_LONG).show();
127        return cursor;
128    }
129
130}