Theming

CSS and SCSS

Theming in qooxdoo mobile is done with SCSS. SCSS is an extension for CSS to enable style sheets to be more modular and maintainable. In SCSS you can you use variables, create mixins, import other style files and reuse CSS statements.

Despite our use of SCSS you do not have to be an SCSS expert. The main SCSS parts are maintained by us in the framework. You will usually just need some knowledge of CSS.

If you want to extend or change the qooxdoo mobile themes you should always modify the SCSS files (*.scss) in the folder <APP_ROOT>/source/resource/<APP_NAMESPACE>/mobile/scss. After you modified any SCSS files they have to be compiled into CSS, otherwise you will not see any changes.

SCSS Compilation

qx.Mobile comes with a built-in SCSS compiler that can be used to leverage the changes you make to your application's *.scss files. You can either invoke it manually through its tool/bin/scss.py frontend, or implicitly by running the watch-scss Generator job (see further).

Mind though that this compiler implements roughly version 3.2 of the SCSS language, with some omissions. Some of the issues we have come across are:

  • Data URLs get broken across lines.
  • The ... syntax for variable arguments in mixin calls is not supported.
  • If the first argument to linear-gradient is a degree value (like -45deg), an error will be printed (but the instruction is processed alright).
  • Single quoted strings (i.e. '') aren't preserved! This means that a rule like
div {
  content: 'foo';
}

becomes (compressed):

div{content:foo}

To circumvent this always use double quotes:

div {
  content: "foo";
}

which becomes (compressed):

div{content:"foo"}

If you like to use one of those features, or want to use newer features of SCSS, you might want to install the SCSS reference implementation which requires a Ruby and RubyGems installation on your machine. You can use the Ruby compiler everywhere you would use the qooxdoo built-in compiler.

Watching SCSS files with qooxdoo's built-in SCSS compiler

Layout design through CSS is typically done by experimentation. You often change a stylesheet and reload the corresponding application to see the effect. Using SCSS you would need to compile the SCSS file after each change of your stylesheet files.

To automatically compile the SCSS files on change/save, you can use the generator watch-scss job:

./generate.py watch-scss

It recognizes any changes made to the SCSS files in your qx.Mobile application and triggers the compilation to CSS automatically.

Watching SCSS files with SASS tool

If you decide to use the official SASS compiler, please follow these steps for watching changes:

  1. Switch to <APP_ROOT>/source/resource/<APP_NAME>/mobile/scss
  2. Start the SASS watching tool with:
sass -I <QOOXDOO_PATH>/framework/source/resource/qx/mobile/scss/ --watch .:../css

As mentioned before, it needs the official SASS compiler installed on your system.

qx.Mobile Themes

qx.Mobile provides a theme for the iOS platform and one for Android. These themes are not intended to be changed/customized by developers directly, but can be extended.

The third one of our themes is the "Indigo" theme. This theme can be modified by developers in many ways, like setting colors or change the used border radius etc.

Switching themes in your qx.Mobile application

You can change the used theme of your qx.Mobile application by opening the config.json in your application root. There you find the macro called MOBILE_THEME. You can change the macro to one of the following values:

  • ios
  • android
  • custom

After changing this macro you have to run the source job in your application's root:

./generate.py source

Extending the iOS or Android theme

You can add your own CSS rules on top of the iOS or Android theme. Just append your statements to the following file:

<APP_ROOT>/source/resource/<APP_NAME>/mobile/css/styles.css

Using a custom theme

In the qx.Mobile Showcase you can have a look at our default theme, called "Indigo". You can use and modify this theme in many ways.

For customization, please follow these steps:

  1. For enabling the customized theming, you have to change the variable MOBILE_THEME in your <APP_ROOT>/config.json to custom:

    "MOBILE_THEME" : "custom"

    After changing the variable please run

    ./generate.py source

    once.

  2. Now start the SCSS watch job by running

    ./generate.py watch-scss

    in your application's root.

  3. Have a look in your application's resource folder: <APP_ROOT>/source/resource/<APP_NAME>/mobile/scss/_styles.scss

    This is the key file for customizing our default theme to your needs.

    In _styles.scss you find various variables for the customization of your qx.Mobile application. The variables overwrite the default theme "Indigo". Undeclared variables get styled like in the "Indigo" theme.

  4. Give it a try: Change the background of the NavigationBar to the color green:

    $navigationbar-background-color: green;

    Your customized theme is compiled automatically by the SCSS watch job to: <APP_ROOT>/source/resource/<APP_NAME>/mobile/css/styles.css

  5. Reload your qx.Mobile application and check your changes. It should look like this:

    ../../_images/customizedTheme.png

That is all you need to know for customizing the theme of a qx.Mobile app. Try the other SCSS variables of your _styles.scss!

Extending the customized theme with SCSS

Additionally to the customization of the variables in _styles.scss you can extend the theme with your own CSS rules. In this case you can append your CSS statement to the following file:

<APP_ROOT>/source/resource/<APP_NAME>/mobile/css/styles.css

As mentioned before, you do not need to be an expert in SCSS for theming. But if you want to know more about this exciting CSS enhancement technology, please have a look at the SASS website:

Improving your theming workflow

With these steps you are able to improve the layouting workflow of your qx.Mobile application:

This plug-in recognizes when a website's CSS has changed and updates the CSS automatically, without a reload of the site. This plug-in works perfectly in combination with our SCSS watch-job.

The result: You just have to change a qx.Mobile's SCSS, save it and the qx.Mobile application in Chrome updates after a few seconds, and keeps the current state of the application.

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