Using multiple column layouts isn't generally recommended on a mobile device because of the narrow screen width, but there are times where you may need to place small elements side-by-side (like buttons or navigation tabs, for example).
The jQuery Mobile framework provides a simple way to build CSS-based columns through a block style class convention called ui-grid.
There are four preset configurations layouts that can be used in any situation that requires columns:
ui-grid-a class)ui-grid-b class)ui-grid-c class)ui-grid-d class)Grids are 100% width, completely invisible (no borders or backgrounds) and don't have padding or margins, so they shouldn't interfere with the styles of elements placed inside them.
Within the grid container, child elements are assigned ui-block-a/b/c/d in a sequential manner which makes each "block" element float side-by-side, forming the grid. The ui-block-a class essentially clears the floats which will start a new line (see multiple row grids, below).
To build a two-column (50/50%) layout, start with a container with a class of ui-grid-a, and add two child containers inside it classed with ui-block-a for the first column and ui-block-b for the second:
<div class="ui-grid-a">
<div class="ui-block-a"><strong>I'm Block A</strong> and text inside will wrap</div>
<div class="ui-block-b"><strong>I'm Block B</strong> and text inside will wrap</div>
</div><!-- /grid-a -->
The above markup produces the following content layout:
As you see above, by default grid blocks have no visual styling; they simply present content side-by-side.
Grid classes can be applied to any container. In this next example, we add ui-grid-a to a fieldset, and apply the ui-block classes to the two buttons inside to stretch them each to 50% of the screen width:
<fieldset class="ui-grid-a">
<div class="ui-block-a"><button type="submit" data-theme="c">Cancel</button></div>
<div class="ui-block-b"><button type="submit" data-theme="b">Submit</button></div>
</fieldset>
Theme classes (not data-theme attributes) from the theming system can be added to an element, including grids. On the blocks below, we're adding two classes: ui-bar to add the default bar padding and ui-bar-e to apply the background gradient and font styling for the "e" toolbar theme swatch. For illustration purposes, an inline style="height:120px" attribute is also added to each grid to set each to a standard height.
The other grid layout configuration uses class=ui-grid-b on the parent, and 3 child container elements, each with its respective ui-block-a/b/c class, to create a three-column layout (33/33/33%). Note: These blocks are also styled with theme classes so the grid layout is clearly visible.
<div class="ui-grid-b">
<div class="ui-block-a">Block A</div>
<div class="ui-block-b">Block B</div>
<div class="ui-block-c">Block C</div>
</div><!-- /grid-b -->
This will produce a 33/33/33% grid for our content.
And an example of a 3 column grid with buttons inside:
A four-column, 25/25/25/25% grid is created by specifying class=ui-grid-c on the parent and adding a fourth block. Note: These blocks are also styled with theme classes so the grid layout is clearly visible.
A five-column, 20/20/20/20/20% grid is created by specifying class=ui-grid-d on the parent and adding a fourth block. Note: These blocks are also styled with theme classes so the grid layout is clearly visible.
Grids are designed to wrap to multiple rows of items. For example, if you specify a 3-column grid (ui-grid-b) on a container that has nine child blocks, it will wrap to 3 rows of 3 items each. There is a CSS rule to clear the floats and start a new line when the class=ui-block-a is seen so make sure to assign block classes in a repeating sequence (a, b, c, a, b, c, etc.) that maps to the grid type:
Grids are helpful for creating layouts within a toolbar. Here's a footer with a 3 column grid.