Question

I m reading the Java code of libreoffice and there s one thing I don t really understand. The method updateUI() calls 2 time the method updateUI and they pass as a parameter a Vector variable, BUT this method doesn t accept any parameter. Anybody can explain me what this parameter does ? if updateUI() is called this way:

UnoDataAware.updateUI();

it complains and says:

non-static method cannot be referenced from a static context

Answer 1

There is another method in the second link you provided: (line 203)

 public static void updateUI(Collection dataAwares) {
            for (Iterator i = dataAwares.iterator(); i.hasNext();)
                ((DataAware) i.next()).updateUI();
         }

This is method that is being called 2 times. Static means you have to specify the Class name before you can call it. Unless you are apart of that class.

Users.getFirstName() (example)

Answer 2

I d say the Cross-Reference thingy is bad. Here s the method you are looking for:

DataAware.updateUI(Collection dataAwares)

Answer 3

When you call the static version of this method you are not using it within the context of an instantiated object. This is the reason you need to pass a parameter to the static method so that it knows which objects to update the UI for.

That parameter will allow the static updateUI method to iterate through a collection of DataAware objects and call their updateUI method from a non-static context. That means that the no-parameter updateUI doesn t need a reference to the object because it belongs to an object.

Answer 4

updateUI() is an instance method, so you have to call it from an instance, while updateUI(Collection dataAwares) is a static method, and is called directly from the class.

And from the same source:

         /**
199      * given a collection containing DataAware objects,
200      * calls updateUI() on each memebr of the collection.
201      * @param dataAwares a collection containing DataAware

objects. 202 */

Answer 5

You re looking at the wrong line.

Look at line 203 ,that s the method being called.

Answer 6

This is the function which is called:

public static void updateUI(Collection dataAwares)

not

public void updateUI()

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