To Be Constant or Not to Be Constant

Naming a variable is an important job and you have to think twice before pressing down your key. Recently I’ve found that naming a constant depends on mutability of the variable and its elements (in case it’s a collection). From that, we can confidently give it an appropriate name.

// Constant
static final ImmutableList NAMES = ImmutableList.of("Ed", "Ann");

// Not a constant
static final ImmutableSet mutableElements = ImmutableSet.of(mutable);

Read more at Google Java Style Guide

Posted on by Emerald Hieu 0

CSS Transform Pitfall

When working with Vaadin TreeTable, we run into a serious scrolling issue. The tree scroll accidentally jumps to top every time we do some actions below the fold.

For example:

  • Inline-edit a row then click aside or Enter
  • Right-click unselected row
  • Click aside selected row to close context menu
  • etc.

After investigating and testing around, we found that the issue comes from CSS transform.

.v-table-body {
  -webkit-backface-visibility: hidden;
  -webkit-transform: translateZ(0);
}

The snippet originates from an improvement that accelerates hardware rendering on iOS. Commenting or removing it out has fixed the problems.

We also notice that Firefox 49+ added support for -webkit prefixed versions of a number of CSS transform properties. That explains why the issue occurs severely on both Chrome and Firefox.

Posted on by Emerald Hieu 0

Mapping GoDaddy Domain to Github Pages

For the goal of developing my personal brand, I’ve spent all my money and effort on buying a 10-dollar domain and mapped it to my Github pages. In fact, I had struggled with this job myself for 1 hour until I got it done with the help of my friend Google. These are the steps.

1) Create your Github pages

I’ll assume you already have a website like [yourUsename].github.io.

Don’t know how to create it? Follow this.
Don’t have much time? Go with Jekyll Now.

2) Create a CNAME file

Add your custom domain to that file e.g. “emeraldhieu.me” in my case.

create-cname-file

3) Configure GoDaddy

Login GoDaddy. In “Domain Details”, select “DNS Zone File”.

Create a record “@” that points to “192.30.252.153” in table “A (Host)”.

create-an-a-record

Create a record “www” that points to .github.io in table “CName (Alias)”

create-a-cname-record

4) Wait for changes to be updated

Check your work with this command

dig +nostats +nocomments +nocmd

wait-for-changes

DONE!

Posted on by Emerald Hieu 0

Work Journal

Today my friend @Genzer told me he was writing a work journal to take notes of what he had done in the day.

I think it’s very interesting for everyone to have a place to share professional knowledge, what problems we have and how we solve it.

That’s a good idea indeed.

Posted on by Emerald Hieu 0