fix(label): propagate the lineOverflow label option. close #14506

[marmelo]

Brief Information

This pull request is in the type of:

• bug fixing
• new feature
• others

What does this PR do?

Allows to truncate labels that overflow multiple lines by propagating the lineOverflow label option to ZRender.

Fixed issues

• aAxis的lineOverflow没生效 #14506
• lineOverflow:'truncate' cannot be implemented properly #15248

Details

Before: What was the problem?

It was not possible to limit the number of lines in labels.

After: How does it behave after the fixing?

Please assume the following configuration:

{
    ...
    xAxis: {
        ...
        axisLabel: {
            ...
            width: 80,  // both width and height are required
            height: 30,  // twice the line height, so only 2 lines are displayed
            lineHeight: 15,
            overflow: 'break',
            lineOverflow: 'truncate'  // the option that is now being propagated
        }
    }
}

Please check axisLabel-lineOverflow.html visual test case for more details.

Document Info

One of the following should be checked.

• This PR doesn't relate to document changes
• The document should be updated later
• The document changes have been made in fix(label): propagate the lineOverflow label option echarts-doc#263

Misc

ZRender Changes

• This PR depends on ZRender changes (ecomfe/zrender#xxx).

Related test cases or examples to use the new APIs

• Visual test case axisLabel-lineOverflow.html was added.

Others

Merging options

• Please squash the commits into a single one when merging.

Other information

[echarts-bot]

Thanks for your contribution!
The community will review it ASAP. In the meanwhile, please checkout the coding standard and Wiki about How to make a pull request.

Document changes are required in this PR. Please also make a PR to apache/echarts-doc for document changes and update the issue id in the PR description. When the doc PR is merged, the maintainers will remove the PR: awaiting doc label.

[plainheart]

There are two similar PRs #15404, #14214. A member, @pissang, who implemented this function, said,

ellipsis and lineOverflow are not supported in the labels.

For lineOverflow it's mainly because I thought it is not implemented well yet.

[marmelo]

Hi @plainheart, I agree the PRs are similar but they are old and eventually been closed.
Can you please advise how to push this change through?

About ellipsis, if we try to override the ellipsis string (... by default) also does not work.
The fix is similar, the ellipsis option is not being propagated to ZRender.
I can add this fix to the current PR or create a new one.

Also, lineOverflow: 'ellipsis' config only works if we have a single row of text.
If we have more than one row (like the example in this issue description) the ellipsis will not be rendered.
This is a missing feature of ZRender, not an ECharts issue.

[github-actions]

This PR has been automatically marked as stale because it has not had recent activity. It will be closed in 7 days if no further activity occurs. If you wish not to mark it as stale, please leave a comment in this PR. We are sorry for this but 2 years is a long time and the code base has been changed a lot. Thanks for your contribution anyway.

[github-actions]

This PR has been automatically closed because it has not had recent activity. Sorry for that and we are looking forward to your next contribution.