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（這是我的lunch.class其填充ListView從database.tell我，如果有任何mistakes.im還是新來這個。）如何將數據從sqlite listview傳遞到新的意圖？
public class Lunch extends Activity implements OnItemClickListener {
DBOpener dbopener;
@Override
protected void onCreate(Bundle savedInstanceState) {
//for fullscreen view
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,WindowManager.LayoutParams.FLAG_FULLSCREEN);
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.dinner);
dbopener = new DBOpener(this);
}
// Open the DB, query all subject codes and refresh the listview
// when app resumes
@Override
protected void onResume() {
super.onResume();
// Configure the listview
ArrayList<String> mealNames = new ArrayList<String>();
ListView lstDine = (ListView)this.findViewById(R.id.dine);
lstDine.setAdapter(new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, mealNames));
// Open/create the DB
try {
dbopener.createDatabase(); // Create DB if necessary
dbopener.openDatabase(); // Open the DB
Cursor dinners = dbopener.getLunchNames();
while (dinners.moveToNext()) {
mealNames.add(dinners.getString(0)); // Get the current subj
// code, add to list
}
dinners.close();
// Update the listview
ArrayAdapter<String> ad = (ArrayAdapter<String>)lstDine.getAdapter();
ad.notifyDataSetChanged();
lstDine.setOnItemClickListener(this);
} catch (Exception e) {
Toast.makeText(this, "Could not open DB",
Toast.LENGTH_LONG).show();
}
}
// Close the DB when app pauses
@Override
protected void onPause() {
super.onPause();
dbopener.close();
}
// When user clicks on an item
public void onItemClick(AdapterView<?> parent, View v, int pos, long id) {
// Use subject code from listview to retrieve other
// details with the dbopener
switch(pos)
{
case 0 :
Intent newActivity = new Intent("com.edu.tp.iit.mns.Display");
newActivity.putExtra("1", "2"); // this is where im unaware of the codes.how to pass the strings of value to the next page
startActivity(newActivity);
break;
}
switch(pos)
{
case 1 :
Intent newActivity = new Intent("com.edu.tp.iit.mns.Display");
startActivity(newActivity);
break;
}
switch(pos)
{
case 2 :
Intent newActivity = new Intent("com.edu.tp.iit.mns.Display");
startActivity(newActivity);
break;
}
switch(pos)
{
case 3 :
Intent newActivity = new Intent("com.edu.tp.iit.mns.Display");
startActivity(newActivity);
break;
}
switch(pos)
{
case 4 :
Intent newActivity = new Intent("com.edu.tp.iit.mns.Display");
startActivity(newActivity);
break;
}
switch(pos)
{
case 5 :
Intent newActivity = new Intent("com.edu.tp.iit.mns.Display");
startActivity(newActivity);
break;
}
switch(pos)
{
case 6 :
Intent newActivity = new Intent("com.edu.tp.iit.mns.Display");
startActivity(newActivity);
break;
}
switch(pos)
{
case 7 :
Intent newActivity = new Intent("com.edu.tp.iit.mns.Display");
startActivity(newActivity);
break;
}
}
（這是display.class（圖片2）工程就像一個模板來顯示圖像一樣的動態信息，食品名稱，食品的描述和其評級
public class Display extends Activity {
DBOpener dbopener;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.display);
dbopener = new DBOpener(this);
}
@Override
protected void onResume() {
super.onResume();
// Configure the listview
// ArrayList<String> mealNames = new ArrayList<String>();
// ListView lstDine = (ListView)this.findViewById(R.id.dine);
// lstDine.setAdapter(new ArrayAdapter<String>(this,
// android.R.layout.simple_list_item_1, mealNames));
// Open/create the DB
try {
// dbopener.createDatabase(); // Create DB if necessary
dbopener.openDatabase(); // Open the DB
Toast.makeText(this, " open DB",
Toast.LENGTH_LONG).show();
Cursor dinners = dbopener.getLunchNames();
while (dinners.moveToNext()) {
// mealNames.add(dinners.getString(0)); // Get the current subj
// code, add to list
}
dinners.close();
// Update the listview
// ArrayAdapter<String> ad = (ArrayAdapter<String>)lstDine.getAdapter();
// ad.notifyDataSetChanged();
//
// lstDine.setOnItemClickListener(this);
} catch (Exception e) {
Toast.makeText(this, "Could not open DB",
Toast.LENGTH_LONG).show();
}
}
// Close the DB when app pauses
@Override
protected void onPause() {
super.onPause();
dbopener.close();
}
}
，最後我dpopener文件：
public class DBOpener extends SQLiteOpenHelper {
private static String DB_PATH =
"/data/data/com.edu.tp.iit.mns/databases/"; //path of our database
private static String DB_NAME ="finals"; // Database name
private final Context myContext;
private SQLiteDatabase db;
@Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub
}
public DBOpener(Context context) {
super(context, DB_NAME, null, 1);
myContext = context;
}
public void createDatabase() throws IOException {
boolean dbExists = checkDatabase();
if (dbExists) {
// Do nothing, DB already exists
Log.d("DBOpener", "DB exists");
} else {
// By calling this method an empty database will be created
// in the default system path of your application, which we
// will overwrite with our own database.
Log.d("DBOpener", "DB does not exit - copying from assets");
this.getReadableDatabase();
copyDatabase();
}
}
private boolean checkDatabase() {
SQLiteDatabase checkDB = null;
try {
// Try opening the database
String path = DB_PATH + DB_NAME;
checkDB = SQLiteDatabase.openDatabase(path, null,
SQLiteDatabase.OPEN_READONLY);
} catch (SQLiteException e) {
// If it fails, DB does not exist
}
if (checkDB != null)
checkDB.close(); // Close the DB; we don’t need it now
return checkDB != null;
}
private void copyDatabase() throws IOException {
InputStream istream = myContext.getAssets().open(DB_NAME);
OutputStream ostream = new FileOutputStream(DB_PATH + DB_NAME);
// Transfer bytes from istream to ostream
byte[] buffer = new byte[1024];
int length;
while ((length = istream.read(buffer)) > 0) {
ostream.write(buffer, 0, length);
}
// Close streams
istream.close();
ostream.flush();
ostream.close();
}
public void openDatabase() throws SQLiteException {
db = SQLiteDatabase.openDatabase(DB_PATH + DB_NAME, null,
SQLiteDatabase.OPEN_READWRITE);
}
@Override
public synchronized void close() {
if (db != null)
db.close();
super.close();
}
// Retrieve all subject codes
public Cursor getDinnerNames() {
if (db == null)
return null;
return db.query("dinner", new String[] {"name"},
null, null, null, null, null);
}
// Get details of specific subject
public Cursor getDinnerDetails(String name) {
if (db == null)
return null;
return db.query("dinner", new String[] {"name", "nutrition", "rating"},
"name = ?", new String[] {name}, null, null, null);
}
// Retrieve all subject codes
public Cursor getLunchNames() {
if (db == null)
return null;
return db.query("lunch", new String[] {"name"},
null, null, null, null, null);
}
// Get details of specific subject
public Cursor getLunchDetails(String name) {
if (db == null)
return null;
return db.query("dinner", new String[] {"name", "nutrition", "rating"},
"name = ?", new String[] {name}, null, null, null);
}
// Retrieve all subject codes
public Cursor getBreakfastNames() {
if (db == null)
return null;
return db.query("breakfast", new String[] {"name"},
null, null, null, null, null);
}
// Get details of specific subject
public Cursor getBreakfastDetails(String name) {
if (db == null)
return null;
return db.query("breakfast", new String[] {"name", "nutrition", "rating"},
"name = ?", new String[] {name}, null, null, null);
}
}
u能幫助我開始案例0，以便我可以完成代碼。例如，用戶點擊燒烤雞肉三明治。它將導航到display.class並從數據庫中檢索信息並顯示圖像評分和內容。
對於每一種情況，您都有一個switch語句。你應該有一個單獨的switch語句，裏面有很多例子。閱讀如何正確使用switch語句來幫助清理代碼。 – dymmeh