Given Example doesnt even work :/ about autocomplete

[tttwang23]

I have an Open Source project using auto complete feature.

https://sourceforge.net/projects/cash-flow

Unzip CashFlow.zip, and the complete source tree can be found within src.zip file.

Everything line is parsed against a list of regular expression possibilities.

Autocomplete if cursor is at end of line. A select token types are subject to auto-complete, using case-insensitive comparison order.

I do not use the canned auto-complete classes but rather I implement what I need based on the base abstract classes or at the interface level. Look at PureCompletion.java, TokenCompletion.java and CFCompletionProvider.java

One important tip I can give is that a list of source strings that participates in auto-completion has to be sorted in unique case insensitive order. If s1 and s2 have the same case insensitive order, then you need to compare them again case sensitively and return their case sensitively ordering. If you just use the naive case insensitive ordering then your app might behave badly when doing auto-completion. Some part of auto-complete code requires the list to be sorted in a unique order; other parts need the list to be case insensitive. I have my code to do this case insensitive unique comparison, because this was a very critical piece of code.

My source code is Apache 2.0 licensed.

My copy of the auto-complete source has a few fixes that were not integrated into the main branch; they were previously published as pull request number 36.

[bobbylight]

@Vatolino, can you point to the specific example that does not work for you?

[copypasteearth]

no autocomplete pop up

`public class CodeEditor extends JFrame {

public CodeEditor() {

    JPanel contentPane = new JPanel(new BorderLayout());
    RSyntaxTextArea textArea = new RSyntaxTextArea(20, 60);
    textArea.setSyntaxEditingStyle(SyntaxConstants.SYNTAX_STYLE_JAVA);
    textArea.setCodeFoldingEnabled(true);
    contentPane.add(new RTextScrollPane(textArea));

    // A CompletionProvider is what knows of all possible completions, and
    // analyzes the contents of the text area at the caret position to
    // determine what completion choices should be presented. Most instances
    // of CompletionProvider (such as DefaultCompletionProvider) are designed
    // so that they can be shared among multiple text components.
    CompletionProvider provider = createCompletionProvider();

    // An AutoCompletion acts as a "middle-man" between a text component
    // and a CompletionProvider. It manages any options associated with
    // the auto-completion (the popup trigger key, whether to display a
    // documentation window along with completion choices, etc.). Unlike
    // CompletionProviders, instances of AutoCompletion cannot be shared
    // among multiple text components.
    AutoCompletion ac = new AutoCompletion(provider);
    ac.setListCellRenderer(new CompletionCellRenderer());
    ac.setShowDescWindow(true);

    ac.setParameterAssistanceEnabled(true);

    ac.install(textArea);
    

    ToolTipManager.sharedInstance().registerComponent(textArea);

    setContentPane(contentPane);
    setTitle("AutoComplete Demo");
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    pack();
    setLocationRelativeTo(null);

}

/**
 * Create a simple provider that adds some Java-related completions.
 */
private CompletionProvider createCompletionProvider() {

    // A DefaultCompletionProvider is the simplest concrete implementation
    // of CompletionProvider. This provider has no understanding of
    // language semantics. It simply checks the text entered up to the
    // caret position for a match against known completions. This is all
    // that is needed in the majority of cases.
    DefaultCompletionProvider provider = new DefaultCompletionProvider();

    // Add completions for all Java keywords. A BasicCompletion is just
    // a straightforward word completion.
    provider.addCompletion(new BasicCompletion(provider, "abstract"));
    provider.addCompletion(new BasicCompletion(provider, "assert"));
    provider.addCompletion(new BasicCompletion(provider, "break"));
    provider.addCompletion(new BasicCompletion(provider, "case"));
    // ... etc ...
    provider.addCompletion(new BasicCompletion(provider, "transient"));
    provider.addCompletion(new BasicCompletion(provider, "try"));
    provider.addCompletion(new BasicCompletion(provider, "void"));
    provider.addCompletion(new BasicCompletion(provider, "volatile"));
    provider.addCompletion(new BasicCompletion(provider, "while"));
    provider.addCompletion(new BasicCompletion(provider, "public"));
    provider.addCompletion(new BasicCompletion(provider, "private"));
    provider.addCompletion(new BasicCompletion(provider, "protected"));
    provider.addCompletion(new BasicCompletion(provider, "static"));
    provider.addCompletion(new BasicCompletion(provider, "final"));


    // Add a couple of "shorthand" completions. These completions don't
    // require the input text to be the same thing as the replacement text.
    provider.addCompletion(new ShorthandCompletion(provider, "sysout",
            "System.out.println(", "System.out.println("));
    provider.addCompletion(new ShorthandCompletion(provider, "syserr",
            "System.err.println(", "System.err.println("));

    return provider;

}

public static void main(String[] args) {
    // Instantiate GUI on the EDT.
    SwingUtilities.invokeLater(() -> {
        try {
            String laf = UIManager.getSystemLookAndFeelClassName();
            UIManager.setLookAndFeel(laf);
        } catch (Exception e) { /* Never happens */ }
        new CodeEditor().setVisible(true);
    });
}

}`

[bobbylight]

Note that by default, you need to type Ctrl+Space for the completion popup to appear. Are you doing that?

[copypasteearth]

No I didn't do that, I'll try later, is there a way to make it automatically pop up? That's what I really want

[bobbylight]

To have it automatically pop up is a two step process:

First, enable it via AutoCompletion.setAutoCompleteEnabled(true). Call this on the AutoCompletion instance you create, before setting everything else up.

Then, what keys trigger the completion popup to automatically display is a property of the CompletionProvider. e.g. should it only appear when the user types ".", or should it appear whenever any letter is typed, or something else? This is configurable since determining a set of possible code completions can be an expensive operation, so it should be set conservatively if possible. Any CompletionProvider extending CompletionProviderBase (e.g. any DefaultCompletionProvider) can have this configured via the setAutoActivationRules(boolean letters, String others) method.

[bobbylight]

Closing as a solution was provided.