如何从不同的类调用方法？

Question

I have 2 classes, Main and DialogOne (an owner class for a dialog ui). In Main , I call new DialogOne().center(); This brings up the dialog box. In DialogOne , I have a clickhandler for a button. When the button is clicked, I insert a record into a database.

Main main = new Main(); //because the db.open is in Main

@UiHandler("addBookButton")
void onAddBookButtonClick(ClickEvent event) {
   main.db.transaction(new TransactionCallback() {
      public void onTransactionStart(SQLTransaction tx) {
         tx.executeSql("INSERT INTO products (bookName) VALUES (?)", new Object[] { bookNameTextBox.getText().toString() }); 
      }
      public void onTransactionFailure(SQLError error) {
      }
      public void onTransactionSuccess() {
      }
   });
this.hide();
}

In onTransactionSuccess() , I need to call updateList() which is in Main , so that the list is cleared and re-populated from the database. How would I go about doing that? I tried main.updateList() but it didn't seem to work. Can I do something in Main that waits for onTransactionSuccess() to be hit and then updateList()

Answer 1

For this to work, the JVM would have to remember the context in which the interface was created, so that the reference to main doesn't ever get erased. Java doesn't support that, except when the fields are final. Have a look at the "Anonymous inner class it not a closure" part of this