I query my SQL dat开发者_运维知识库abase to populate my spinners, I have no problem populating the spinner with a string array of the resulting Book Titles (this is a library style app). While getting the Book Titles into the spinner for selection is no problem, what is the best way to tie these titles back to their SQL _id's? I've been looking for a way to make spinners "multi-dimensional" but so far I don't see how.
Any help in the right direction would be much appreciated, thank you!
You definitely want the SimpleCursorAdapter. You must include the _id in the select query. Here is an example...
Spinner spinner = (Spinner) dialog.findViewById(R.id.mm_spinner);
// DatabaseInterface would be your data access class...
DatabaseInterface db = new DatabaseInterface(this);
db.open();
Cursor c = db.getNames(); // This would contain _id, name from a database for example.
SimpleCursorAdapter adapter = new SimpleCursorAdapter(this,
android.R.layout.simple_spinner_item,
c,
new String[] {DatabaseInterface.KEY_ID, DatabaseInterface.KEY_NAME},
new int[] {android.R.id.text1});
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
spinner.setAdapter(adapter);
... This will bind the _id to the spinner id. So when you select an item in the list using the onitemclicklistener like what I posted below. You will have the correct _id's associated with each of the names in the list...
spinner.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView parent, View view, int position, long id){
// id = the _id from the cursor
}
});
What I did is used a multidimensional array for my spinner. It grabs things from string[i][0]
and the ids are in string[i][1]
. Let me grab the code I used for it.
public class BNYDirectory extends Activity {
public static String[] Fields = new String[6];
public static String[][] BookResults;
public ArrayAdapter<CharSequence> booksAdapter;
public ProgressDialog dialog;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.searchscreen);
new getAllData().execute(this);
final EditText fname = (EditText) findViewById(R.id.fname);
final EditText lname = (EditText) findViewById(R.id.lname);
final EditText aim = (EditText) findViewById(R.id.aim);
final EditText phone = (EditText) findViewById(R.id.phone);
final Spinner books = (Spinner) findViewById(R.id.book);
//Sets up and fills the department spinner
booksAdapter = new ArrayAdapter<CharSequence>(BNYDirectory.this, android.R.layout.simple_spinner_item);
booksAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
books.setAdapter(booksAdapter);
//Search button
findViewById(R.id.search).setOnClickListener(new OnClickListener() {
public void onClick(View v) {
//This grabs the ID from the String[][] for the selected spinner item
String bookName = BookResults[(int)books.getSelectedItemId()][0];
String bookId = BookResults[(int)books.getSelectedItemId()][1];
}
});
}
private class getAllData extends AsyncTask<Context, Void, Cursor> {
protected void onPreExecute () {
dialog = ProgressDialog.show(BNYDirectory.this, "",
"Loading. Please wait...", true);
}
@Override
protected Cursor doInBackground(Context... params) {
setBooks();
return null;
}
protected void onPostExecute(Cursor c) {
for(int i = 0 ; i < BookResults.length ; i++){
booksAdapter.add(BookResults[i][0]);
}
dialog.dismiss();
}
}
public static void setBooks(){
//Basically this sets the String[][] DeptResults so that DeptResults[n][0] is the names, and DeptResults[n][1] is the ID that matches for n.
//books[n][0] = book name
//books[n][1] = book ID
BookResults = books;
}
}
Okay, so what this does is uses a class variable String[][] BookResults
to hold both values, the name (in [][0]) and the id (in [][1]). BookResults[10][0]
would be the book name for BookResults[10][1]
's ID. The "search button" in this example shows how you'd get both values.
Look into using a SimpleCursorAdapter with your Spinner and a custom view for the child layouts. :)
Here is a tutorial.
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