一个Android框架下实现登录和Google检索的应用程序
蒋彪@南京 2012-12-21
1. 需求设计
在Android的数据库创建一个login表，包括密码和账户两个字段
实现两个activity应用程序，其中一个，提供两个入力框，分别输入密码和账户，并且实现登录check
登录成功之后，跳转到第二个Activity，在其上实现一个入力框，根据输入的参数，到google上检索
2. 效果图
3. 主要代码
3.1 第一个Activity的代码
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public class Android1 extends Activity { private Button mButton1; private TextView mTextView1; private TextView mTextView2; private String user = new String(); private String password = new String(); private DBHelper dbHelper;
/** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main);
mTextView1 = (TextView) findViewById(R.id.EditText01); mTextView2 = (TextView) findViewById(R.id.EditText02); dbHelper = new DBHelper(this, "TestDB"); createTable();
}
public void onClick(View v) { // TODO Auto-generated method stub user = mTextView1.getText().toString(); password = mTextView2.getText().toString(); Boolean result = selectTable(user, password); Log.d("Android1", "the result is " + result); if (result == true) { Intent intent = new Intent(); intent.setClass(Android1.this, Android2.class); startActivity(intent);
} }
public void createTable() { SQLiteDatabase db = dbHelper.getWritableDatabase(); db .execSQL("create table if not exists LOG (user varchar primary key,password varchar)"); }
public boolean selectTable(String user, String password) { SQLiteDatabase db = dbHelper.getWritableDatabase(); try { Cursor result = db.rawQuery( "select * from LOG where user = ? AND password =?", new String[] { user, password }); Log.d("Android1", "count is " + result.getCount()); if (result.getCount() != 0) { result.close(); db.close(); return true; } else { result.close(); db.close(); return false; } } catch (SQLException ex) { Log.d("Android1", "select table failure"); return false; } }
} |
3.2 第二个Activity的代码
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public class Android2 extends Activity { private TextView mTextView1;
@Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.search); mTextView1 = (TextView) findViewById(R.id.EditTextSearch); }
public void onClick(View v) { String key = mTextView1.getText().toString(); Intent search = new Intent(Intent.ACTION_WEB_SEARCH);
search.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
search.putExtra(SearchManager.QUERY, key);
final Bundle appData = getIntent().getBundleExtra( SearchManager.APP_DATA);
if (appData != null) {
search.putExtra(SearchManager.APP_DATA, appData);
}
startActivity(search);
} } |
3.3 数据库访问控制类
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public class DBHelper extends SQLiteOpenHelper {
// 数据库版本 private static final int VERSION = 1;
// 新建一个表
public DBHelper(Context context, String name, CursorFactory factory, int version) { super(context, name, factory, version);
}
public DBHelper(Context context, String name, int version) { this(context, name, null, version); }
public DBHelper(Context context, String name) { this(context, name, VERSION); }
@Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
@Override public void onCreate(SQLiteDatabase arg0) { // TODO Auto-generated method stub
}
} |
4. 总结
总体上说起来需求比较简单，代码也比较匆忙，细节上还是有很多值得改进的地方。
@以上@