帮助，不显示保存的数据到数据库。这是代码：
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.compose_message);
mDbHelper = new MessagesDBAdapter(this);
mDbHelper.open();
btnRecipient = (Button) findViewById(R.id.button_recipient_picker);
btnSend = (Button) findViewById(R.id.button_send);
editTextRecipient = (EditText) findViewById(R.id.editText_recipient);
editTextRecipient.setInputType(0);
editTextNewMessage = (EditText) findViewById(R.id.editText_new_message);
spinnerTimeDelay = (Spinner) findViewById(R.id.spinner_delay);
tv_details = (TextView) findViewById(R.id.tv_details);
spinnerTimeDelay.setOnItemSelectedListener(this);
ArrayAdapter<String> aa=new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item,items);
aa.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spinnerTimeDelay.setAdapter(aa);
mRowId = (savedInstanceState == null) ? null://
(Long) savedInstanceState.getSerializable(MessagesDBAdapter.KEY_ROWID);
if (mRowId==null) {
Bundle extras=getIntent().getExtras();
mRowId=extras!=null ? extras.getLong(MessagesDBAdapter.KEY_ROWID):null;
}
populateFields();
btnRecipient.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Intent intent = new Intent(Intent.ACTION_PICK, ContactsContract.Contacts.CONTENT_URI);
startActivityForResult(intent, CONTACT_PICKER_RESULT);
}
});
mDbHelper.close();
}
// Spinner
public void onItemSelected(AdapterView<?> parent,
View view, int pos, long id) {
count=pos;
if(FirstLoad){
FirstLoad = false;
return;
}
Toast.makeText(parent.getContext(), "You chose " +
parent.getItemAtPosition(pos).toString()+ " to delay", Toast.LENGTH_LONG).show();
}
public void onNothingSelected(AdapterView<?> parent) {
return;
}
public void showProgress () {
dialog = new ProgressDialog(this);
dialog.setCancelable(true);
dialog.setMessage("Sending Message .. ");
dialog.show();
}
// Contact Picker
@Override
public void onActivityResult(int reqCode, int resultCode, Intent data) {
super.onActivityResult(reqCode, resultCode, data);
switch (reqCode) {
case (CONTACT_PICKER_RESULT):
if (resultCode == Activity.RESULT_OK) {
StringBuilder sb = new StringBuilder();
Uri contactData = data.getData();
Cursor contactsCursor = managedQuery(contactData,
null, null, null, null);
if (contactsCursor.moveToFirst()) {
String id = contactsCursor.getString(contactsCursor
.getColumnIndexOrThrow(ContactsContract.Contacts._ID));
String name = contactsCursor.getString(contactsCursor
.getColumnIndexOrThrow(ContactsContract.Contacts.DISPLAY_NAME));
String hasPhoneNumber = contactsCursor.getString(contactsCursor
.getColumnIndexOrThrow(ContactsContract.Contacts.HAS_PHONE_NUMBER));
sb.append(name);
if (Integer.parseInt(hasPhoneNumber) > 0) {
Uri myPhoneUri = Uri.withAppendedPath(
ContactsContract.CommonDataKinds.Phone.CONTENT_URI, id);
Cursor phoneCursor = managedQuery(
myPhoneUri, null, null, null, null);
for (phoneCursor.moveToFirst(); !phoneCursor.isAfterLast(); phoneCursor.moveToNext()) {
String phoneNumber = phoneCursor.getString(phoneCursor
.getColumnIndexOrThrow(ContactsContract.CommonDataKinds.Phone.NUMBER));
sb.append(phoneNumber);
}
} else {
sb.append("This contact doesn't have a phone number");
}
editTextRecipient.setText(sb.toString());
}
}
break;
}
btnSend.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
String phoneNo = editTextRecipient.getText().toString();
String message = editTextNewMessage.getText().toString();
Log.d(phoneNo, message);
saveState(phoneNo, message);
boolean split = false;
/*SimpleDateFormat s = new SimpleDateFormat("ddMMyyyyhhmmss");
//String date = s.format(new Date());
Calendar c = Calendar.getInstance();
Timestamp timeStamp = new Timestamp(c.get(Calendar.YEAR)-1900, c.get(Calendar.MONTH),
c.get(Calendar.DATE), c.get(Calendar.HOUR), c.get(Calendar.MINUTE), c.get(Calendar.SECOND), 0);
//saveState(phoneNo, message);*/
final Toast toast = Toast.makeText(getBaseContext(),
"Your message " + "\"" + message + "\"" + " is sent to " +"\""+ phoneNo+"\"",
Toast.LENGTH_SHORT);
Runnable showToastRunnable = new Runnable() {
public void run() {
dialog.cancel();
toast.show();
}
};
if (phoneNo.length()>0 && message.length()>0) {
showProgress();
if (count == 0) {
handler.postDelayed(showToastRunnable, 0);
}
else if (count == 1) {
handler.postDelayed(showToastRunnable, 15000);
}
else if (count == 2) {
handler.postDelayed(showToastRunnable, 30000);
}
else if (count == 3) {
handler.postDelayed(showToastRunnable, 60000);
}
}
// sendSMS(phoneNo, message, split); */
else
Toast.makeText(getBaseContext(),
"Please enter both phone number and message.",
Toast.LENGTH_SHORT).show();
}
});
mDbHelper.close();
}
private void populateFields() {
if (mRowId!=null) {
Cursor message=mDbHelper.fetchNote(mRowId);
startManagingCursor(message);
editTextRecipient.setText(message.getString(message.getColumnIndexOrThrow(MessagesDBAdapter.KEY_RECIPIENT)));
editTextNewMessage.setText(message.getString(message.getColumnIndexOrThrow(MessagesDBAdapter.KEY_MESSAGE)));
}
}
private void saveState(String phoneNo, String message) {
Log.i(phoneNo, message);
if (mRowId==null) {
long id = mDbHelper.createNote(phoneNo, message);
if (id > 0) {
mRowId = id;
}
} else {
mDbHelper.updateNote(mRowId, phoneNo, message);
}
}
}
这是另一个：
public class Inbox extends ListActivity {
ListView list;
private static final int ACTIVITY_CREATE=0;
private static final int ACTIVITY_EDIT=1;
private static final int INSERT_ID = Menu.FIRST;
private static final int DELETE_ID = Menu.FIRST + 1;
private MessagesDBAdapter mDbHelper;
private Cursor mMessagesCursor;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.inbox);
mDbHelper = new MessagesDBAdapter(this);
mDbHelper.open();
fillData();
registerForContextMenu(getListView());
list = (ListView) findViewById(android.R.id.list);
}
private void fillData() {
mMessagesCursor = mDbHelper.fetchAllNotes();
startManagingCursor(mMessagesCursor);
String[] from = new String[]{MessagesDBAdapter.KEY_RECIPIENT, MessagesDBAdapter.KEY_MESSAGE};
int[] to = new int[]{R.id.tv_recipient, R.id.tv_details};
SimpleCursorAdapter messages =
new SimpleCursorAdapter(this, R.layout.message_custom_row, mMessagesCursor, from, to);
}
/*@Override
public boolean onCreateOptionsMenu(Menu menu) {
super.onCreateOptionsMenu(menu);
menu.add(0, INSERT_ID, 0, R.string.menu_insert);
return true;
}
@Override
public boolean onMenuItemSelected(int featureId, MenuItem item) {
switch(item.getItemId()) {
case INSERT_ID:
createNote();
return true;
}
return super.onMenuItemSelected(featureId, item);
}*/
@Override
public void onCreateContextMenu(ContextMenu menu, View v,
ContextMenuInfo menuInfo) {
super.onCreateContextMenu(menu, v, menuInfo);
menu.add(0, DELETE_ID, 0, R.string.menu_delete);
}
@Override
public boolean onContextItemSelected(MenuItem item) {
switch(item.getItemId()) {
case DELETE_ID:
AdapterContextMenuInfo info = (AdapterContextMenuInfo) item.getMenuInfo();
mDbHelper.deleteNote(info.id);
fillData();
return true;
}
return super.onContextItemSelected(item);
}
private void createNote() {
Intent i = new Intent(this, KAHTextApp.class);
startActivityForResult(i, ACTIVITY_CREATE);
}
@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
super.onListItemClick(l, v, position, id);
Cursor c = mMessagesCursor;
c.moveToPosition(position);
Intent i = new Intent(this, KAHTextApp.class);
i.putExtra(MessagesDBAdapter.KEY_ROWID, id);
i.putExtra(MessagesDBAdapter.KEY_RECIPIENT, c.getString(
c.getColumnIndexOrThrow(MessagesDBAdapter.KEY_RECIPIENT)));
i.putExtra(MessagesDBAdapter.KEY_MESSAGE, c.getString(
c.getColumnIndexOrThrow(MessagesDBAdapter.KEY_MESSAGE)));
startActivityForResult(i, ACTIVITY_EDIT);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent intent) {
super.onActivityResult(requestCode, resultCode, intent);
Bundle extras = intent.getExtras();
switch(requestCode) {
case ACTIVITY_CREATE:
String recipient = extras.getString(MessagesDBAdapter.KEY_RECIPIENT);
String message = extras.getString(MessagesDBAdapter.KEY_MESSAGE);
mDbHelper.createNote(recipient, message);
fillData();
break;
case ACTIVITY_EDIT:
Long rowId = extras.getLong(MessagesDBAdapter.KEY_ROWID);
if (rowId != null) {
String editTitle = extras.getString(MessagesDBAdapter.KEY_RECIPIENT);
String editBody = extras.getString(MessagesDBAdapter.KEY_MESSAGE);
mDbHelper.updateNote(rowId, editTitle, editBody);
}
fillData();
break;
}
}
}
然后是数据库：
public class MessagesDBAdapter {
public static final String KEY_RECIPIENT = "recipient";
public static final String KEY_MESSAGE = "message";
public static final String KEY_ROWID = "_id";
private static final String TAG = "MessagesDBAdapter";
private DatabaseHelper mDbHelper;
private SQLiteDatabase mDb;
//Database creation sql statement
private static final String DATABASE_CREATE =
"create table notes (" + KEY_ROWID + " integer primary key autoincrement, "
+ KEY_RECIPIENT + " text not null, " + KEY_MESSAGE + " text not null);";
private static final String DATABASE_NAME = "data";
private static final String DATABASE_TABLE = "notes";
private static final int DATABASE_VERSION = 2;
private final Context mCtx;
private static class DatabaseHelper extends SQLiteOpenHelper {
DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(DATABASE_CREATE);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
Log.w(TAG, "Upgrading database from version " + oldVersion + " to "
+ newVersion + ", which will destroy all old data");
db.execSQL("DROP TABLE IF EXISTS notes");
onCreate(db);
}
}
/**
* Constructor - takes the context to allow the database to be
* opened/created
*
* @param ctx the Context within which to work
*/
public MessagesDBAdapter(Context ctx) {
this.mCtx = ctx;
}
public MessagesDBAdapter open() throws SQLException {
mDbHelper = new DatabaseHelper(mCtx);
mDb = mDbHelper.getWritableDatabase();
return this;
}
public void close() {
mDbHelper.close();
}
public long createNote(String phoneNo, String message) {
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_RECIPIENT, phoneNo);
initialValues.put(KEY_MESSAGE, message);
open();
return mDb.insert(DATABASE_TABLE, null, initialValues);
}
public boolean deleteNote(long rowId) {
return mDb.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0;
}
public Cursor fetchAllNotes() {
return mDb.query(DATABASE_TABLE, new String[] {KEY_ROWID, KEY_RECIPIENT,
KEY_MESSAGE}, null, null, null, null, null);
}
public Cursor fetchNote(long rowId) throws SQLException {
Cursor mCursor =
mDb.query(true, DATABASE_TABLE, new String[] {KEY_ROWID,
KEY_RECIPIENT, KEY_MESSAGE}, KEY_ROWID + "=" + rowId, null,
null, null, null, null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
public boolean updateNote(long rowId, String phoneNo, String message) {
ContentValues args = new ContentValues();
args.put(KEY_RECIPIENT, phoneNo);
args.put(KEY_MESSAGE, message);
return mDb.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null) > 0;
}
}
我不知道我错过了什么，或者删除了但是数据没有保存在数据库中。谁能帮我？这里没有错误，数据不仅显示在列表视图中。
答案 0 :(得分：0)
您创建了一个SimpleCursorAdapter，但是您没有将其提供给ListView。在fillData（）中创建适配器后添加setListAdapter（消息）。
注意：在ListActivity中，您可以使用getListView（）获取ListView，您不需要使用findViewById（）。这与你的问题无关，只是一个信息：）