Request multiple cells from SQLite database in android
I am trying to call data from two different cells in my database then combine them and print them out in an activity.
I am using the following code:
public Cursor getGermanDescription(String id) {
String[] args = { id };
return (getReadableDatabase()
.rawQuery(
"SELECT _id,Column1,Column2 FROM Databasing_Details WHERE _id=?",
args));
With the above I am only getting the content of Column1 but not Column2. I am passing the String id to another activity.
My cursor adapter is:
@Override public void onCreate(Bundle savedInstanceState) { try { super.onCreate(savedInstanceState); setContentView(R.layout.main);
//Get our passed variable from our intent's EXTRAS
passedVar=getIntent().getStringExtra(ListViewTwo.ID_EXTRA);
//this is our ListView element, obtained by id from our XML layout
ListView myListView = (ListView)findViewById(R.id.list_view);
String string = passedVar;
int passedInt = Integer.parseInt(string);
if (passedInt==1) { passedVar1 = true;
}
//create our database Helper
dbDescriptionHelper=new DatabaseHelper(this);
//a set of results from a database query
ourCursor=dbDescriptionHelper.getGermanDescription(passedVar);
//tell android to start managing the cursor,
startManagingCursor(ourCursor);
//create our adapter
adapter=new SlangAdapter(ourCursor);
//set the adapter!!!
myListView.setAdapter(adapter);
} catch (Exception e) {
Log.e("ERROR", "ERROR IN CODE: " + e.toString());
e.printStackTrace();
}
return;
}
class SlangAdapter extends CursorAdapter {
SlangAdapter(Cursor c) {
super(ListViewFinal.this, c);
}
@Override
public void bindView(View row, Context ctxt,
Cursor c) {
DescriptionHolder holder=(DescriptionHolder)row.getTag();
holder.populateFrom(c, dbDescriptionHelper);
}
@Override
public View newView(Context ctxt, Cursor c,
ViewGroup parent) {
LayoutInflater inflater=getLayoutInflater();
View row=inflater.inflate(R.layout.main_row, parent, false);
DescriptionHolder holder=new DescriptionHolder(row);
row.setTag(holder);
return(row);
}
}
static class DescriptionHolder {
private TextView name=null;
DescriptionHolder(View row) {
name=(TextView)row.findViewById(R.id.row);
}
void populateFrom(Cursor c, DatabaseHelper r) {
name.setText(r.getName(c));
}
}
Could someone point out where I am going wrong please.
OK, I have found the answer.
My syntax was incorrect, what I needed to write for my cursor was:
public Cursor getGermanDescription(String id) {
String[] args = { id };
return (getReadableDatabase()
.rawQuery(
"SELECT _id, ObjectDescriptionGerman ||'nn'|| ObjectDescription FROM Databasing_Details WHERE _id=?",
args));
}
The || needs to be used instead of "," or "AND". I have also inserted line breaks between my two returned value so I do not need to do this in my database.
链接地址: http://www.djcxy.com/p/49644.html上一篇: Chrome和Firefox之间的差异