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yy1020

小结下android中的autocomplete和sqlite的知识点，顺便复习下。
1 SQLITE帮助类
public class SQLiteCountryAssistant extends SQLiteOpenHelper {

private static final String DB_NAME = "usingsqlite.db";

private static final int DB_VERSION_NUMBER = 1;

private static final String DB_TABLE_NAME = "countries";

private static final String DB_COLUMN_1_NAME = "country_name";

private static final String DB_CREATE_SCRIPT = "create table "

+ DB_TABLE_NAME

+ " (_id integer primary key autoincrement, country_name text not null);)";

private SQLiteDatabase sqliteDBInstance = null;



public SQLiteCountryAssistant(Context context) {

super(context, DB_NAME, null, DB_VERSION_NUMBER);

}



@Override

public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

// TODO: Implement onUpgrade

}



@Override

public void onCreate(SQLiteDatabase sqliteDBInstance) {

Log.i("onCreate", "Creating the database...");

sqliteDBInstance.execSQL(DB_CREATE_SCRIPT);

}



public void openDB() throws SQLException {

Log.i("openDB", "Checking sqliteDBInstance...");

if (this.sqliteDBInstance == null) {

Log.i("openDB", "Creating sqliteDBInstance...");

this.sqliteDBInstance = this.getWritableDatabase();

}

}



public void closeDB() {

if (this.sqliteDBInstance != null) {

if (this.sqliteDBInstance.isOpen())

this.sqliteDBInstance.close();

}

}



public long insertCountry(String countryName) {

ContentValues contentValues = new ContentValues();

contentValues.put(DB_COLUMN_1_NAME, countryName);

Log

.i(this.toString() + " - insertCountry", "Inserting: "

+ countryName);

return this.sqliteDBInstance.insert(DB_TABLE_NAME, null, contentValues);

}



public boolean removeCountry(String countryName) {

int result = this.sqliteDBInstance.delete(DB_TABLE_NAME,

"country_name='" + countryName + "'", null);

if (result > 0)

return true;

else

return false;

}



public long updateCountry(String oldCountryName, String newCountryName) {

ContentValues contentValues = new ContentValues();

contentValues.put(DB_COLUMN_1_NAME, newCountryName);

return this.sqliteDBInstance.update(DB_TABLE_NAME, contentValues,

"country_name='" + oldCountryName + "'", null);



}



public String[] getAllCountries() {

Cursor cursor = this.sqliteDBInstance

.query(DB_TABLE_NAME, new String[] { DB_COLUMN_1_NAME }, null,

null, null, null, null);

if (cursor.getCount() > 0) {

String[] str = new String[cursor.getCount()];

int i = 0;

while (cursor.moveToNext()) {

str = cursor.getString(cursor

.getColumnIndex(DB_COLUMN_1_NAME));

i++;

}

return str;

} else {

return new String[] {};

}

}
复制代码2 使用的autocomplete类
public class UsingSQLite extends Activity

{

private SQLiteCountryAssistant sqlliteCountryAssistant;

@Override

public void onCreate(Bundle savedInstanceState)

{

super.onCreate(savedInstanceState);

setContentView(R.layout.main);

final AutoCompleteTextView textView = (AutoCompleteTextView) findViewById(R.id.autocompleteCountry);

sqlliteCountryAssistant = new SQLiteCountryAssistant(UsingSQLite.this);

sqlliteCountryAssistant.openDB();

// Insert a few countries that begin with "C"

sqlliteCountryAssistant.insertCountry("Cambodia");

sqlliteCountryAssistant.insertCountry("Cameroon");

sqlliteCountryAssistant.insertCountry("Canada");

sqlliteCountryAssistant.insertCountry("Cape Verde");

sqlliteCountryAssistant.insertCountry("Cayman Islands");

sqlliteCountryAssistant.insertCountry("Chad");

sqlliteCountryAssistant.insertCountry("Chile");

sqlliteCountryAssistant.insertCountry("China");

//sqlliteCountryAssistant.removeCountry("Chad");

//sqlliteCountryAssistant.updateCountry("Canada", "Costa Rica");

String[] countries = sqlliteCountryAssistant.getAllCountries();

// Print out the values to the log

for(int i = 0; i < countries.length; i++)

{

Log.i(this.toString(), countries);

}

ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, R.layout.list_item, countries);

textView.setAdapter(adapter);

}

public void onDestroy()

{

super.onDestroy();

sqlliteCountryAssistant.close();

}

}
复制代码

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