Swallow

Edje Swallow

The parent of all layout widgets is Edje. Edje as explained in the Edje Parts and Blocks using text description. One of its main features is the possibility to create "Swallows" objects. When this kind of object is added in an Evas, it contains any other Evas_Object. To create a swallow part, create first the EDC file:

collections
{
   group
   {
      name: "container";
      parts
      {
         part
         {
            name: "part.swallow"
            type: SWALLOW;
            description
            {
               state: "default" 0.0;
               rel1.offset: 31 31;
               rel2.offset: -32 -32;
            }
         }
      }
   }
}

This EDC describes a group named container, with one part inside of type SWALLOW and with the name part.swallow. This part is centered inside the parent (it is the default behavior) but there are 32 pixels free all around this part. Use edje_cc to compile the EDC file into a binary EDJ file:

edje_cc -o container.edj container.edc

Create an Edje object and load this file:

edje = edje_object_add(evas_object_evas_get(parent));
edje_object_file_set(edje, "container.edj", "container");

Note: edje_object_add as opposed as all elementary object, does not take an Evas_Object as a parent. Give it the Evas on which the object is added. As the parent is already added on an Evas by elementary, retrieve a reference on it by using the evas_object_evas_get API.

edje_object_file_set is used to set the Edje file from which the object is loaded. The object itself is the name of the group as defined in the EDC file, in this case it is "container".

Use the API edje_object_swallow to swallow any kind of Evas_Object inside.

ic = elm_icon_add(parent);
elm_image_file_set(ic, "c1.png", NULL);
edje_object_part_swallow(edje, "part.swallow", ic);

Note: The elm_image_file_set() function parameters are linked to Edje. The second argument in this example is a PNG file; however, it can also be an Edje file. In that case, the third argument must be the Edje group to load, exactly as previously shown with the edje_object_file_set() function.

Create complex layout for your application with Edje. It is may not be the most easy way, but it is the most powerful. This Edje layout is used all around elementary and is the basis of the layout widget.