On create method;
db = openOrCreateDatabase("messages", MODE_PRIVATE, null);
db.execSQL("CREATE TABLE IF NOT EXISTS message(msg TEXT);");
db.execSQL("INSERT INTO message values('example');");
listeview1 = (ListView) findViewById(R.id.listview);
ArrayList<String> dbArray = myArrayListTodatabase();
ListAdapter mylistadapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1, dbArray);
listview.setAdapter(mylistadapter);
Myarraylisttodatabase code;
public ArrayList<String> myArrayListTodatabase() {
db = openOrCreateDatabase("messages", MODE_PRIVATE, null);
db.rawQuery("Select * from message", null);
Cursor c = db.rawQuery("Select * from message", null);
c.moveToFirst();
String dbString = "";
while (!c.isAfterLast()) {
if (c.getString(c.getColumnIndex("msg")) != null) {
dbString += c.getString(c.getColumnIndex("msg"));
dbString += "\n";
}
c.moveToNext();
}
db.close();
return myArraylist;
}
Global variables
SQLiteDatabase db = null;
public ArrayList<String> myArraylist = new ArrayList<String>();
Im using these but there is no output in listview when i run the app
You are not adding content to the ArrayList at all. Add myArraylist.Add(dbString)
or something to fill your ArrayList for your ListView to use.
You forgot to insert into ArrayList. Update your function with below one:
public ArrayList<String> myArrayListTodatabase() {
myArraylist.clear();
db = openOrCreateDatabase("messages", MODE_PRIVATE, null);
db.rawQuery("Select * from message", null);
Cursor c = db.rawQuery("Select * from message", null);
String dbString = "";
while (c.moveToNext()) {
if (!c.getString(c.getColumnIndex("msg")).equals("")) {
myArraylist.add(c.getString(c.getColumnIndex("msg")));
}
}
c.close();
db.close();
return myArraylist;
}
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