How to create different headers or footers on the first page of a document
Using Ibex you can create a document which has different headers and footers on different pages; that difference might be in the content of the header or footer or in its size and placement on the page.
This example shows how to create a document which different footer on the first page than all the other pages. The techniques shown here can be applied to the page header as well as the footer.
Approach
We want to create a document where the first page is different to the other pages. The approach we take is to create two different simple-page-master elements, one to define the layout for the first page, and the other to define the layout for all other pages.
Defining page masters
The simple-page-master for the first page looks like this:
<fo:simple-page-master master-name="first-page" page-width="8.5in" page-height="8in">
<fo:region-body margin="3cm" region-name="body"/>
<fo:region-after extent="2cm" region-name="first-page-footer"/>
</fo:simple-page-master>
This defines the geometry for a body region and a footer region named "first-page-footer".
The simple-page-master for all other pages looks like this:
<fo:simple-page-master master-name="other-page" page-width="8.5in" page-height="8in">
<fo:region-body margin="3cm" region-name="body"/>
<fo:region-after extent="2cm" region-name="other-page-footer"/>
</fo:simple-page-master>
This defines the geometry for a body region and a footer region named "other-page-footer".
Choosing a page master
The two simple-page-master elements have different master-name attributes. We use this to distinguish between them. In addition to the two simple-page-master elements we need a page-sequence-master element; this controls the creation a sequence of pages. At the start of each page Ibex looks at the page-sequence-master element and determines which simple-page-master to use for that page.
The page-sequence-master for this example looks like this:
<fo:page-sequence-master master-name="pages">
<fo:repeatable-page-master-alternatives>
<fo:conditional-page-master-reference page-position="first" master-reference="first-page"/>
<fo:conditional-page-master-reference master-reference="other-page"/>
</fo:repeatable-page-master-alternatives>
</fo:page-sequence-master>
The page-sequence-master contains a repeatable-page-master-alternatives element, which contains a list of conditional-page-master-reference elements. At the start of each page, Ibex looks at this list and chooses one conditional-page-master-reference, which is then used to select which simple-page-master applies to that page.
On the first page, the condition [page-position="first"] is true, so that conidtional-page-master-reference is used, and the simple-page-master called "first-page" is selected.
On all other pages the condition [page-position="first"] is false, and the second conditional-page-master-reference is used, so the simple-page-master called "other-page" is selected.
It is important to realise that the order of the conditional-page-master-reference elements is crucial. At the start of each page Ibex looks at each conditional-page-master-reference in turn until it finds one for which the conditions are true. At that point the searching stops and other conditional-page-master-reference elements are not considered.
A common error is to do this:
<fo:page-sequence-master master-name="pages">
<fo:repeatable-page-master-alternatives>
<fo:conditional-page-master-reference master-reference="other-page"/>
<fo:conditional-page-master-reference page-position="first" master-reference="first-page"/>
</fo:repeatable-page-master-alternatives>
</fo:page-sequence-master>
In the FO above the first conditional-page-master-reference has no conditional attributes (such as page-position), so it will always be selected. In this document all the pages will have the same layout. Associating the flow with page masters
The page-sequence element should have its master-reference attribute set to the master-name of the page-sequence-master, not the names of any of the simple-page-master elements. Creating footer content
The page-sequence element should contain static-content elements for both types of page, the first page and the other pages. So the page-sequence looks like this:
<fo:page-sequence master-reference="pages">
<fo:static-content flow-name="first-page-footer">
<fo:block>
page <fo:page-number/>
</fo:block>
<fo:block>this is the first page footer</fo:block>
</fo:static-content>
<fo:static-content flow-name="other-page-footer">
<fo:block>
page <fo:page-number/>
</fo:block>
<fo:block>this is the other page footer</fo:block>
</fo:static-content>
<fo:flow flow-name="xsl-region-body">
<fo:block>
Lorem ipsum dolor sit amet, consectetuer adipiscing elit.
</fo:block>
At the start of each page Ibex identifies which simple-page-master will be used on that page by evaluating the page-sequence-master element. Having identified which simple-page-master is used, Ibex now knows what regions will appear on that page.
On the first page the applicable simple-page-master is the one with master-name="first-page", so the regions on the page are named "body" and "first-page-footer".
On the second and all subsequent pages the applicable simple-page-master is the one with master-name="other-page", so the regions on the page are named "body" and "other-page-footer".
Having found the list of region names for that page, Ibex finds any flow or static-content elements whose flow-name attribute matches one of the regions on the page and renders the content of those flows. static-content elements whose flow-name does not match one of the regions on the page are ignored.