I am learning Android. I have a problem and I can\'t solve it. I want to retrieve data from an existing database and display it in a TextView
after click button
You may use this following code actually it is rough but plz check it out
db = openOrCreateDatabase("sms.db", SQLiteDatabase.CREATE_IF_NECESSARY, null);
Cursor cc = db.rawQuery("SELECT * FROM datatable", null);
final ArrayList<String> row1 = new ArrayList<String>();
final ArrayList<String> row2 = new ArrayList<String>();
if(cc!=null) {
cc.moveToFirst();
startManagingCursor(cc);
for (int i=0; i<cc.getCount(); i++) {
String number = cc.getString(0);
String message = cc.getString(1);
row1.add(number);
row2.add(message);
final EditText et3 = (EditText) findViewById(R.id.editText3);
final EditText et4 = (EditText) findViewById(R.id.editText4);
Button bt1 = (Button) findViewById(R.id.button1);
bt1.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
switch (v.getId()) {
case R.id.button1:
et3.setText(row1.get(count));
et4.setText(row2.get(count));
count++;
break;
default:
break;
}
}
});
cc.moveToNext();
}
on button click, first open the database, fetch the data and close the data base like this
public class cytaty extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.galeria);
Button bLosuj = (Button) findViewById(R.id.button1);
bLosuj.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
myDatabaseHelper = new DatabaseHelper(cytaty.this);
myDatabaseHelper.openDataBase();
String text = myDatabaseHelper.getYourData(); //this is the method to query
myDatabaseHelper.close();
// set text to your TextView
}
});
}
}
and your getYourData()
in database class would be like this
public String[] getAppCategoryDetail() {
final String TABLE_NAME = "name of table";
String selectQuery = "SELECT * FROM " + TABLE_NAME;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
String[] data = null;
if (cursor.moveToFirst()) {
do {
// get the data into array, or class variable
} while (cursor.moveToNext());
}
cursor.close();
return data;
}
TextView tekst = (TextView) findViewById(R.id.editText1);
You cannot cast EditText
to TextView
.
First cast your Edit text like this:
TextView tekst = (TextView) findViewById(R.id.editText1);
tekst.setText(text);
And after that close the DB not befor this line...
myDataBaseHelper.close();
You are using getData() method as void.
You can not return values from void.