Add columns to optionset fields

code/BootstrapOptionsetField.php

@@ -10,6 +10,28 @@
  */
 class BootstrapOptionsetField extends BootstrapFormField {
 
+	/**
+	 * An array of column_name => span_length pairs.
+	 * @example
+	 * <code>
+	 * array (
+	 * 	'xs' => 12,
+	 * 	'sm' => 12,
+	 * 	'md' => 6,
+	 * 	'lg' => 3
+	 * )
+	 * </code>
+	 * @var array
+	 */
+	protected $columnCounts = array ();	
+
+
+	/**
+	 * Number of columns in the options layout
+	 * @var int
+	 */
+	protected $numberOfColumns;
+
 
 	/**
 	 * Enable or disable "inline" presentation, in which
@@ -22,4 +44,79 @@ public function setInline($bool = true) {
 		$this->owner->Inline = $bool;
 		return $this->owner;
 	}
+
+
+	/**
+	 * Sets the column layout for the options
+	 * @param array $cols An array of column_name => span_length pairs
+	 * @see  $columnCounts
+	 * 
+	 * @return   OptionsetField
+	 */
+	public function setColumns($cols) {
+		if(!is_array($cols)) {
+			throw new Exception("BootstrapOptionsetField::setColumns must be passed an array.");
+		}
+
+		$allowed_keys = array('lg','md','sm','xs');
+		$diff = array_diff($allowed_keys, array_keys($cols));
+		if(!empty($diff)) {
+			throw new Exception("BootstrapOptionsetField::setColumns must be passed an array with keys " . implode(', ', $allowed_keys));
+		}
+
+		$this->columnCounts = $cols;
+
+		$maxSpan = max(array_values($this->columnCounts));
+		$minSpan = min(array_values($this->columnCounts));
+		$this->numberOfColumns = ceil($maxSpan/$minSpan);
+
+		return $this->owner;
+	}
+
+
+	/**
+	 * Tells whether this option set is using a columnar layout
+	 *
+	 * @return boolean
+	 */
+	public function HasColumns() {
+		return !empty($this->columnCounts);
+	}
+
+
+	/**
+	 * Number of columns in the layout
+	 *
+	 * @return  int
+	 */
+	public function ColumnCount() {
+		return $this->numberOfColumns;
+	}
+
+
+	/**
+	 * A list of classes for the column divs
+	 *
+	 * @return  string
+	 */
+	public function ColumnClasses() {
+		$classes = array();
+		foreach($this->columnCounts as $colName => $val) {
+			$classes[] = "col-{$colName}-{$val}";
+		}
+
+		return implode(" ", $classes);
+	}
+
+
+	/**
+	 * Number of options per column
+	 *
+	 * @return  int
+	 */
+	public function PerColumn() {		
+		return ceil(count($this->owner->getSource())/$this->numberOfColumns);
+	}
+
+
 }

templates/BootstrapCheckboxSetField.ss

@@ -1,12 +1,28 @@
     <% if $Options.Count %>
+        <% if $HasColumns %>
+            <div class="row">
+                <div class="$ColumnClasses">
+                <% loop $Options %>                    
+                    <div class="checkbox <% if $Up.Inline %>inline<% end_if %>">
+                        <label>
+                            <input id="$ID" class="checkbox" name="$Name" type="checkbox" value="$Value"<% if $isChecked %> checked="checked"<% end_if %><% if $isDisabled %> disabled="disabled"<% end_if %>>
+                            $Title
+                        </label>
+                    </div>
+                    <% if $Up.HasColumns && $MultipleOf($Up.PerColumn) %></div><div class="$Up.ColumnClasses"><% end_if %>                                    
+                <% end_loop %>
+                </div>
+            </div>
+        <% else %>
             <% loop $Options %>
-                <div class="checkbox <% if $Top.Inline %>inline<% end_if %>">
+                <div class="checkbox <% if $Up.Inline %>inline<% end_if %>">
                     <label>
                         <input id="$ID" class="checkbox" name="$Name" type="checkbox" value="$Value"<% if $isChecked %> checked="checked"<% end_if %><% if $isDisabled %> disabled="disabled"<% end_if %>>
                         $Title
                     </label>
-                </div>
+                </div>                
             <% end_loop %>
-        <% else %>
-            <li>No options available</li>
+        <% end_if %>
+    <% else %>
+        <li>No options available</li>
     <% end_if %>