# 13. Go To Symbol Contributor

> For the complete documentation index, see [llms.txt](https://plugins.jetbrains.com/docs/intellij/llms.txt).

> **TL;DR**
> Reference: [Go to Class and Go to Symbol](go-to-class-and-go-to-symbol.html)
>
>
>
> Code: [SimpleChooseByNameContributor](https://github.com/JetBrains/intellij-sdk-code-samples/tree/main/simple_language_plugin/src/main/java/org/intellij/sdk/language/SimpleChooseByNameContributor.java), [SimplePsiImplUtil](https://github.com/JetBrains/intellij-sdk-code-samples/tree/main/simple_language_plugin/src/main/java/org/intellij/sdk/language/psi/impl/SimplePsiImplUtil.java)

> **Tip:**
> This page is part of multi-step [Custom Language Support Tutorial](custom-language-support-tutorial.html). All previous steps must be executed in sequence for the code to work.

A Go to Symbol Contributor helps the user to navigate to any PSI element by its name.

## Define a Helper Method for Generated PSI Elements

To specify what a PSI element looks like in the `Navigate | Symbol` popup window, Structure tool window, or other components, it should implement `getPresentation()`. This method gets defined in the utility class `SimplePsiImplUtil`, and the parser and PSI classes must be regenerated. Add the following method to [SimplePsiImplUtil](https://github.com/JetBrains/intellij-sdk-code-samples/tree/main/simple_language_plugin/src/main/java/org/intellij/sdk/language/psi/impl/SimplePsiImplUtil.java):

```JAVA
public static ItemPresentation getPresentation(final SimpleProperty element) {
  return new ItemPresentation() {
    @Nullable
    @Override
    public String getPresentableText() {
      return element.getKey();
    }

    @Nullable
    @Override
    public String getLocationString() {
      PsiFile containingFile = element.getContainingFile();
      return containingFile == null ? null : containingFile.getName();
    }

    @Override
    public Icon getIcon(boolean unused) {
      return element.getIcon(0);
    }
  };
}
```

In addition, to provide an icon for the displayed items, extend [IconProvider](https://github.com/JetBrains/intellij-community/tree/idea/262.10968.63/platform/core-api/src/com/intellij/ide/IconProvider.java) and register it in [com.intellij.iconProvider](https://jb.gg/ipe?extensions=com.intellij.iconProvider) extension point . See [SimplePropertyIconProvider](https://github.com/JetBrains/intellij-sdk-code-samples/tree/main/simple_language_plugin/src/main/java/org/intellij/sdk/language/SimplePropertyIconProvider.java):

```JAVA
final class SimplePropertyIconProvider extends IconProvider {

  @Override
  public @Nullable Icon getIcon(@NotNull PsiElement element, int flags) {
    return element instanceof SimpleProperty ? SimpleIcons.FILE : null;
  }

}
```

## Update Grammar and Regenerate the Parser

Now add the `SimplePsiImplUtil.getPresentation()` to the `property` methods definition in the `Simple.bnf` grammar file by replacing the `property` definition with the lines below. Don't forget to regenerate the parser after updating the file! Right-click on the `Simple.bnf` file and select Generate Parser Code.

```BNF
property ::= (KEY? SEPARATOR VALUE?) | KEY {
  mixin="org.intellij.sdk.language.psi.impl.SimpleNamedElementImpl"
  implements="org.intellij.sdk.language.psi.SimpleNamedElement"
  methods=[getKey getValue getName setName getNameIdentifier getPresentation]
}
```

## Define a Go To Symbol Contributor

To contribute items to `Navigate | Symbol` results, subclass [ChooseByNameContributorEx](https://github.com/JetBrains/intellij-community/tree/idea/262.10968.63/platform/lang-impl/src/com/intellij/navigation/ChooseByNameContributorEx.java) to create [SimpleChooseByNameContributor](https://github.com/JetBrains/intellij-sdk-code-samples/tree/main/simple_language_plugin/src/main/java/org/intellij/sdk/language/SimpleChooseByNameContributor.java):

```JAVA
final class SimpleChooseByNameContributor implements ChooseByNameContributorEx {

  @Override
  public void processNames(@NotNull Processor<? super String> processor,
                           @NotNull GlobalSearchScope scope,
                           @Nullable IdFilter filter) {
    Project project = Objects.requireNonNull(scope.getProject());
    List<String> propertyKeys = ContainerUtil.map(
        SimpleUtil.findProperties(project), SimpleProperty::getKey);
    ContainerUtil.process(propertyKeys, processor);
  }

  @Override
  public void processElementsWithName(@NotNull String name,
                                      @NotNull Processor<? super NavigationItem> processor,
                                      @NotNull FindSymbolParameters parameters) {
    List<NavigationItem> properties = ContainerUtil.map(
        SimpleUtil.findProperties(parameters.getProject(), name),
        property -> (NavigationItem) property);
    ContainerUtil.process(properties, processor);
  }

}
```

## Register the Go To Symbol Contributor

The `SimpleChooseByNameContributor` implementation is registered with the IntelliJ Platform in the plugin configuration file using the [com.intellij.gotoSymbolContributor](https://jb.gg/ipe?extensions=com.intellij.gotoSymbolContributor) extension point .

```XML
<extensions defaultExtensionNs="com.intellij">
  <gotoSymbolContributor
      implementation="org.intellij.sdk.language.SimpleChooseByNameContributor"/>
</extensions>
```

## Run the Project

[Run](creating-plugin-project.html#running-the-plugin) the plugin.

The IDE now supports navigating to a property definition by name pattern via `Navigate | Symbol` action.

![Go To Symbol](images/go_to_symbol.png)