hxuanyu/intellij-sdk-code-samples
1
0
Fork 0
mirror of https://github.com/JetBrains/intellij-sdk-code-samples.git synced 2025-07-30 18:27:49 +08:00
Code Issues Packages Projects Releases Wiki Activity

line_marker_provider.md: minor

Browse Source
This commit is contained in:
Yann Cébron 2021-04-14 14:56:21 +02:00
parent d70ec2e044
commit 8ca1de56b0
1 changed files with 4 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
topics/tutorials/custom_language_support/line_marker_provider.md
View File

@ -1,6 +1,6 @@
[//]: # (title: 8. Line Marker Provider)
<!-- Copyright 2000-2020 JetBrains s.r.o. and other contributors. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file. -->
<!-- Copyright 2000-2021 JetBrains s.r.o. and other contributors. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file. -->
Line markers help annotate code with icons on the gutter.
These markers can provide navigation targets to related code.
@ -18,10 +18,12 @@ For this example, override the `collectNavigationMarkers()` method to collect us
## Best Practices for Implementing Line Marker Providers
This section addresses important details about implementing a marker provider.
The `collectNavigationMarkers()` method should:
* Only return line marker information consistent with the element passed into the method.
For example, do not return a _class_ marker if `getLineMarkerInfo()` was called with an element that corresponds to a _method_.
* Return line marker information for the appropriate element at the correct scope of the PSI tree.
Return leaf elements only - i.e., the smallest possible elements.
For example, do not return method marker for [`PsiMethod`](upsource:///java/java-psi-api/src/com/intellij/psi/PsiMethod.java).
Instead, return it for the [`PsiIdentifier`](upsource:///java/java-psi-api/src/com/intellij/psi/PsiIdentifier.java) which contains the name of the method.
@ -50,7 +52,7 @@ However, if a method like `actionPerformed()` is not completely visible in the E
* The second pass tries to add a line marker because `MyWrongLineMarkerProvider()` is called for the `PsiMethod`.
As a result, _the line marker icon would blink annoyingly_.
To fix this problem, rewrite `MyWrongLineMarkerProvider` to return info for `PsiIdentifier` instead of `PsiMethod` as shown below:
To fix this problem for this case, rewrite `MyWrongLineMarkerProvider` to return info for `PsiIdentifier` instead of `PsiMethod` as shown below:
```java
public class MyCorrectLineMarkerProvider implements LineMarkerProvider {