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POJava MVC - Doesn't feel like I get it
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copied!<p>As a beginner in programming it always bugs me when I run into a walls. Currently one of the wall are co-depending objects. </p> <p>As you can see in my question history I'm currently working on a blackberry application, in which I implemented something I call the MVC Pattern, but it isn't exactly what I think it's meant to be.</p> <p>You see, a novice programmer you look on abstracts like this graphic and you get the idea behind it. But implementing it is another thing.</p> <p><a href="http://www.ibm.com/developerworks/wireless/library/wi-arch6/theoretical.gif" rel="nofollow noreferrer">alt text http://www.ibm.com/developerworks/wireless/library/wi-arch6/theoretical.gif</a></p> <p>Please, don't stop reading :) I'm showing you some of me code, which contains some blackberry specific stuff, but you should see what I'm doing.</p> <p><strong>Main Entry Point for my Application</strong> </p> <pre><code>public class ContactManager extends UiApplication { private static ContactManagerMainScreenModel MainScreenModel = new ContactManagerMainScreenModel(); private static ContactManagerMainScreen MainScreenView = null; public static void main(String[] args) { new ContactManager().enterEventDispatcher(); } public ContactManager() { MainScreenView = new ContactManagerMainScreen(MainScreenModel); // Displays the Splashscreen then opens the Mainscreen new SplashScreen(UiApplication.getUiApplication(), MainScreenView); } } </code></pre> <p><strong>The Mainscreen Model</strong> </p> <pre><code>public class ContactManagerMainScreenModel { ContactManagerMainScreen v; // Loading Local Storage LocalContactStorage LocalContactStorage = new LocalContactStorage(); // Define Data List private Vector vContacts_Favorites; public void register(ContactManagerMainScreen v) { this.v = v; } // Retrieve Favorite Contacts from Persistant Storage public Vector getFavoriteContactsFromLocalStorage() { vContacts_Favorites = LocalContactStorage.getFavoriteContactsFromLocalStorage(); return vContacts_Favorites; } // Put Retrieve Favorite Contacts from Persistant Storage public void saveFavoriteContactsToLocalStorage() { LocalContactStorage.saveFavoriteContactsToLocalStorage(vContacts_Favorites); } } </code></pre> <p><strong>The MainScreenController</strong></p> <pre><code>public class ContactManagerMainScreenController { private ContactManagerMainScreenModel _model = null; private ContactManagerMainScreen _view = null; public ContactManagerMainScreenController(ContactManagerMainScreen view, ContactManagerMainScreenModel model) { this._model = model; this._view = view; } public void HideFavoriteList() { if( this._view._ContactList.getManager() != null) { this._view._ContactList.getManager().delete(this._view._ContactList); } else { this._view._bottom_box.add(this._view._ContactList); } } } </code></pre> <p>Still there? Okay ... </p> <p>My Problem here is, that I want to use the controller to change UI Elements, like Displaying a PopUp Box, hide someting or other things.</p> <p>But all these UI Elements are defined in the View (here ContactManagerMainScreen) so have to give to the Controller a reference to the View. Which leads to my co-depending objects misery.</p> <p>I cannot create the controller before the view is declared. Without the requirement to allow the controller to change UIElements, it would be no problem (as shown in the Graphics).</p> <p>What I'm doing now is that the View creates the Controller </p> <pre><code>controller = new ContactManagerMainScreenController(this , model); </code></pre> <p>Does that makes sense? I want to understand the pattern, so call my code trash or anything you like :) I just want to learn something.</p> <p>P.S. I beg your pardon for my bad english :)</p>

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