How to display class canvas for menulist in a class not midlet and it's class call in midlet?
In the class that extends MIDlet, obtain an instance of Display object using getDisplay API with the instance of MIDlet passed as parameter to that method. Make that Display object available where you need to use it (study Java basics if you don't know how to do that)
Whenever you need to display a canvas (or any other Displayable object for that matter), use display object mentioned above to invoke setCurrent method with an instance of canvas passed as parameter to that method
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WHAT I HAVE is a standard JavaFX application: Main.java, MainController.java & main.fxml. To add custom component, I created CustomComponentController.java and custom_component_controller.fxml.
PROBLEM is that in CustomComponentController methods I need to reference other methods and standard components from MenuController. I add public static MainController mc; to MainController class body, so that it can be seen from CustomComponentController (MainController.mc.neededMethod()). Then I try to pass everything to it in MainController.initialize() method (mc = this;) - when debugging this breakpoint, I see this full of components instances, but mc remains with null components afterwards.
QUESTION is how to reference the running instance of MainController to use its components and methods in other classes and to crossreference different custom components from each other? How to clean MainController code from event handlers and assistance methods of components by moving it all to component's own class?
I tried the following approaches, but found no way to make them work without errors:
Accessing FXML controller class
How can I access a Controller class in JavaFx 2.0?
JavaFX 2.0 + FXML. Updating scene values from a different Task
JavaFX 2.2 -fx:include - how to access parent controller from child controller
The problem can be solved if you comply the following conditions:
Not only public, but obligatory static MainController mc should be.
Do not forget id in fxml for CustomComponentController: <CustomComponentController fx:id="cc"/>, where cc is the name of the "#FXML imported" CustomComponentController in your MainController class.
Omit parameter fx:controller="main.CustomComponentController" in custom_component_controller.fxml as it results in "Controller value already specified" error (a conflict between main.fxml and custom_component_controller.fxml markup declared controllers).
Put mc = this; in the beginning of MainController's initialize() method. Before using mc in CustomComponentController class, check if it's not null. It can be null when all components, including CustomComponentController, are instantiated at application startup, but there is no mc instance yet. MainController method initialize() where MainController is instantiated is called after components are loaded. Therefore better practice is to use approach in the next paragraph.
In main.fxml create primary component of the same type that CustomComponentController and with the only fx:id parameter. Replace primary component with your CustomComponentController by creating reloadCustomComponents() method and calling it from CustomComponentController's initialize() method. Do it by adding the following to reloadCustomComponents() method:
customComponentAnchorPane.getChildren().remove(customComponent);
customComponent = new customComponent();
customComponentAnchorPane.getChildren().add(customComponent);
Thus all components can be placed outside CustomComponentController with all their methods and reloaded at the startup of the apllication. All component declarations stay in MainController class and can be reached through MainController mc reference. No duplicate creating of components in detail with parameters is needed.
Your problem looks like the classic catalog-crud forms updating, I implemented an interface that I called Updatable with an update method so I could reference any catalog form with any crud form easy after passing Controller Main Class as the UserData Property of the Child Root Component's Form
Hope it Can Solve your problem
If I declare something like
#FXML
private final static double PREF_SPACING = 10d;
or
#FXML
private Insets insets = new Insets(10d);
in the controller class,
is there a way to use their values in Scene Builder?
When I want to change the value, I want to change
it only once, in the controller class.
PRELIMINARY ANSWER
I haven't yet tried all of the techniques below, but it seems to be the way you would do it from reading the documentation. If I get some time, I'll try it out later and update this answer with results (or somebody else can do this and post a new answer or edit this one to create a definitive answer). I just wanted to publish something now to point you in what I believe to be the right direction.
If the below is not what you are looking for, add a few more specifics to your questions to fully describe what you want.
Don't using the #FXML annotation here. #FXML is for injecting values from the markup into the controller, not the other way around.
For your first example which is a constant, let's say your controller class is:
class MyControllerType {
public final static double PREF_SPACING = 10d;
}
Then in your fxml, reference the constant:
<?import MyControllerType?>
...
<VBox>
<spacing><MyControllerType fx:constant="PREF_SPACING"/></spacing>
</VBox>
For your second sample which is not a constant or a part of the SceneGraph, you can use an fx:define element to instantiate an instance of the class. Note that you can't directly instantiate an Insets class from FXML as it has no builder class nor zero length constructor. So what you might be able to do is create another placeholder class for the information and instantiate a reference to that in your FXML (or you can create a Builder that FXML can use to instantiate the Insets).
class InsetsHolder {
private Insets insets = new Insets(10d);
public Insets getInsets();
}
<?import InsetsHolder?>
<fx:define>
<InsetsHolder fx:id="i"/>
</fx:define>
<VBox>
<Button text="Click Me!" VBox.margin="$i.insets"/>
</VBox>
SceneBuilder should be able to read fxml files which use the fx:define and fx:constant notation, as well as (possibly) make use of the reference expression $i.insets. SceneBuilder might not have any UI to allow you to edit the values from within the SceneBuilder application, so you will probably need to hand edit the fxml file portions related to the fx:define and fx:constant elements if you wish to make use of these structures.
There is an executable example of using an fx:define element in this mailing list post on designing resolution independent units in FXML.
In general, I think I'd be a bit cautious of maintaining these kind of dependencies between fxml and java code. It may be more prudent to do more of this kind of stuff in plain Java code within the context of the controller initialize method as scottb suggests.
The #FXML annotation enables the JavaFX objects whose names you defined (fx:id) to have their references reflectively injected into nonpublic fields in the controller object as the scene graph is loaded from the fxml markup.
To the best of my knowledge, this is a one way operation. There is no provision for having named static class variables in the controller object injected into the scene graph during loading.
You can accomplish something very similar to what you are requesting by defining the values that you want set as class variables in your controller object's class, and then setting the appropriate object properties programmatically (rather than in markup) in the initialize() method of your controller object.
The initialize() method is called (if it is present) after the loading of the scene graph is complete (so all the GUI objects will have been instantiated) but before control has returned to your application's invoking code.
I have a RPC method that returns a List of Strings. I want to create a ComboBox with a store that will load the values through a RpcProxy, but I can't find an example that doesn't use some sort of ModelData class.
I would prefer not to have to create a simple Bean with only one property (the string) and then have to convert the List one item at a time.
My ideal would be to create something like this:
RpcProxy<List<String>> proxy = new RpcProxy<List<String>>()...
Any suggestions?
Unfortunately, with GXT 2.2.5, you can't get around not using ModelData.
The class definition for ComboBox says it all:
public class ComboBox<D extends ModelData> extends TriggerField<D> implements SelectionProvider<D> {
...
protected ListStore<D> store;
...
So, at this point your biggest concern is keeping your code clean. If you have to make a specialized ModelData derived class, you could subclass ComboBox and keep a nested class definition for your wrapper object.
If you're not tied to using GXT 2.2.5, I would update to GXT 3.0.x and GWT 2.5.0. GXT 3 moved away from using ModelData. Now, everything accepts bean-like objects.
I have a class that functions as an async TCP Client. In that class, I have a callback function, such as Client_Connected. This fires when my TCP Client has been connected. In my main viewcontroller class, I have an instance of the TCPClient and a label that I want to display the status of the tcpclient.
My question is, in the callback function of the tcpclient class, how can I reference and set the label's text in my mainviewcontroller's class?
When you create your TCPClient class, pass in a reference to your parent class (or just a reference to the label you want to update) - then your "child" class will have access to the element on the "parent" that needs to be updated.
There are probably other approaches, but this is fairly common.
I have a class which inherits from CListCtrl class, say class list.
I have another class dlg, which inherits from CDialog.
Class dlg contains an instance of class list.
I have got a delete button in class dlg, on which I delete the selected item in listCtrl and do lots of other processing.
I want the same functionality on delete key.
I added OnKeyDown() fn is my class list, where I can capture VK_DELETE key. But my problem is that, how do I do otehr processing that I need to do in dialog class.
All that processing is dlg class based not list class based.
I have many such dlg classes with different data and in every dlg class processing is different.
I tried capturing VK_DELETE in dialog class, but it doesn't capture it if focus is on list class.
I am totally stuck and have no idea, how to do this.
Please give me some idea how i can do this.
Thanks,
SG
What about delegating the call captured in the List class to the parent Dialog class. Thus you capture the VK_DELETE on the List class and say to the parent that you received a Delete command. Thus you can keep all your processing on the parent Dialog class if you wish.
((CMyParentDialog*) GetParent())->OnDeleteKeyPressed(this);
Or better, create a custom message and post it to the parent window.
#define W_DELETE_PRESSED_ON_LIST (WM_USER + 1)
GetParent()->PostMessage(WM_DELETE_PRESSED_ON_LIST);