In the example, the "Update second word" button has been pressed three times, to update the word. ObservableList wordsList = FXCollections.observableArrayList(word ->Ī full example demonstrating the usage of an extractor. For this to work, the Word class has been updated to use properties for its fields rather than simple types. Note that, the list containing the words is already observable and ListView will take care of handling changes to that list, but if you modified the word definition for instance within a displayed word object, then your list view wouldn't pick up changes to the definition without appropriate listener logic in the ListView cell factory (or, preferably, an extractor).Įxample of extractor definition for an ObservableList of the Word objects. If you also want your UI to update as the observable properties of your objects change, then you need to make your list cells aware of the changes to the associated items, by listening for changes to them (which is quite a bit more complex in this case, an extractor can help). Just adding and removing to the underlying observable items list will trigger updates to the view. For example in the cell factory, as item is a Word, use item.word() rather than item.getWord() to get the word string from the Word. Then, whenever you access the fields in the records, don't use the get prefix. tCellFactory(param -> new ListCell() void updateItem(Word item, boolean empty) I advise using a cell factory to solve this problem. I have done a bit of research on the web and there seems to be a thing called 'Cell Factories', but it seems unnecessarily complicated for what seems to be such a simple problem, and as I stated before, I'm a bit of a newbie when it comes to programming.Ĭan anyone help? This is my first time here, so I'm sorry if I haven't included enough of my code or I've done something wrong. Just to be clear, this isn't for android, and the list of words will be changed, saved, and loaded eventually, so I can't just make another array to hold the wordStrings. In such a way that, rather than taking Words directly from wordsList, it accesses the wordString property in each Word of my observableArrayList? My question here is, specifically, is there a simple way to rewrite this: ListView listViewOfWords = new ListView(wordsList) You can see where this is going- the code compiles and works, but when I display it in my application, rather than displaying the titles of every word in the ListView, it displays the Word object itself as a String! ListView listViewOfWords = new ListView(wordsList) Įach Word object only has 2 properties: wordString (A string of the word), and definition (Another string that is the word's definition). WordsList.add(new Word("Third Word", "Definition of Third Word") WordsList.add(new Word("Second Word", "Definition of Second Word") WordsList.add(new Word("First Word", "Definition of First Word") I would like to use a custom object I made called Words: ObservableList wordsList = FXCollections.observableArrayList() ListView listViewOfStrings = new ListView(wordsList) īut I don't want to use Strings. In most of the tutorials I have looked up regarding populating a ListView (Using an ObservableArrayList, more specifically) the simplest way to do it is to make it from an ObservableList of Strings, like so: ObservableList wordsList = FXCollections.observableArrayList("First word","Second word", "Third word", "Etc.") I'm a bit new to Java, JavaFX, and programming in general, and I have an issue that is breaking my brain.
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