1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
|
<?xml version="1.0" encoding="UTF-8"?>
<!-- Reviewed: no -->
<sect3 id="zend.view.helpers.initial.headstyle">
<title>HeadStyle Helper</title>
<para>
The <acronym>HTML</acronym> <emphasis><style></emphasis> element is used to include
<acronym>CSS</acronym> stylesheets inline in the <acronym>HTML</acronym>
<emphasis><head></emphasis> element.
</para>
<note>
<title>Use HeadLink to link CSS files</title>
<para>
<link linkend="zend.view.helpers.initial.headlink">HeadLink</link>
should be used to create <emphasis><link></emphasis> elements for
including external stylesheets. <classname>HeadStyle</classname> is used when
you wish to define your stylesheets inline.
</para>
</note>
<para>
The <classname>HeadStyle</classname> helper supports the following methods for
setting and adding stylesheet declarations:
</para>
<itemizedlist>
<listitem>
<para>
<command>appendStyle($content, $attributes = array())</command>
</para>
</listitem>
<listitem>
<para>
<command>offsetSetStyle($index, $content, $attributes = array())</command>
</para>
</listitem>
<listitem>
<para>
<command>prependStyle($content, $attributes = array())</command>
</para>
</listitem>
<listitem>
<para>
<command>setStyle($content, $attributes = array())</command>
</para>
</listitem>
</itemizedlist>
<para>
In all cases, <varname>$content</varname> is the actual <acronym>CSS</acronym> declarations.
<varname>$attributes</varname> are any additional attributes you wish to provide to the
<property>style</property> tag: lang, title, media, or dir are all permissible.
</para>
<note>
<title>Setting Conditional Comments</title>
<para>
<classname>HeadStyle</classname> allows you to wrap the style tag in conditional
comments, which allows you to hide it from specific browsers. To add the conditional
tags, pass the conditional value as part of the <varname>$attributes</varname> parameter
in the method calls.
</para>
<example id="zend.view.helpers.initial.headstyle.conditional">
<title>Headstyle With Conditional Comments</title>
<programlisting language="php"><![CDATA[
// adding scripts
$this->headStyle()->appendStyle($styles, array('conditional' => 'lt IE 7'));
]]></programlisting>
</example>
</note>
<para>
<classname>HeadStyle</classname> also allows capturing style declarations; this
can be useful if you want to create the declarations programmatically,
and then place them elsewhere. The usage for this will be showed in an
example below.
</para>
<para>
Finally, you can also use the <methodname>headStyle()</methodname> method to
quickly add declarations elements; the signature for this is
<methodname>headStyle($content$placement = 'APPEND', $attributes = array())</methodname>.
<varname>$placement</varname> should be either 'APPEND', 'PREPEND', or 'SET'.
</para>
<para>
<classname>HeadStyle</classname> overrides each of <methodname>append()</methodname>,
<methodname>offsetSet()</methodname>, <methodname>prepend()</methodname>, and
<methodname>set()</methodname> to enforce usage of the special methods as listed above.
Internally, it stores each item as a <property>stdClass</property> token, which it later
serializes using the <methodname>itemToString()</methodname> method. This allows you
to perform checks on the items in the stack, and optionally modify these
items by simply modifying the object returned.
</para>
<para>
The <classname>HeadStyle</classname> helper is a concrete implementation of the
<link linkend="zend.view.helpers.initial.placeholder">Placeholder
helper</link>.
</para>
<note>
<title>UTF-8 encoding used by default</title>
<para>
By default, Zend Framework uses <acronym>UTF-8</acronym> as its default encoding, and,
specific to this case, <classname>Zend_View</classname> does as well. Character encoding
can be set differently on the view object itself using the
<methodname>setEncoding()</methodname> method (or the <varname>encoding</varname>
instantiation parameter). However, since <classname>Zend_View_Interface</classname> does
not define accessors for encoding, it's possible that if you are using a custom view
implementation with this view helper, you will not have a
<methodname>getEncoding()</methodname> method, which is what the view helper uses
internally for determining the character set in which to encode.
</para>
<para>
If you do not want to utilize <acronym>UTF-8</acronym> in such a situation, you will
need to implement a <methodname>getEncoding()</methodname> method in your custom view
implementation.
</para>
</note>
<example id="zend.view.helpers.initial.headstyle.basicusage">
<title>HeadStyle Helper Basic Usage</title>
<para>
You may specify a new style tag at any time:
</para>
<programlisting language="php"><![CDATA[
// adding styles
$this->headStyle()->appendStyle($styles);
]]></programlisting>
<para>
Order is very important with <acronym>CSS</acronym>; you may need to ensure that
declarations are loaded in a specific order due to the order of the
cascade; use the various append, prepend, and offsetSet directives
to aid in this task:
</para>
<programlisting language="php"><![CDATA[
// Putting styles in order
// place at a particular offset:
$this->headStyle()->offsetSetStyle(100, $customStyles);
// place at end:
$this->headStyle()->appendStyle($finalStyles);
// place at beginning
$this->headStyle()->prependStyle($firstStyles);
]]></programlisting>
<para>
When you're finally ready to output all style declarations in your
layout script, simply echo the helper:
</para>
<programlisting language="php"><![CDATA[
<?php echo $this->headStyle() ?>
]]></programlisting>
</example>
<example id="zend.view.helpers.initial.headstyle.capture">
<title>Capturing Style Declarations Using the HeadStyle Helper</title>
<para>
Sometimes you need to generate <acronym>CSS</acronym> style declarations
programmatically. While you could use string concatenation,
heredocs, and the like, often it's easier just to do so by creating
the styles and sprinkling in <acronym>PHP</acronym> tags.
<classname>HeadStyle</classname> lets you do just that, capturing it to the stack:
</para>
<programlisting language="php"><![CDATA[
<?php $this->headStyle()->captureStart() ?>
body {
background-color: <?php echo $this->bgColor ?>;
}
<?php $this->headStyle()->captureEnd() ?>
]]></programlisting>
<para>
The following assumptions are made:
</para>
<itemizedlist>
<listitem>
<para>
The style declarations will be appended to the stack. If you
wish for them to replace the stack or be added to the top,
you will need to pass 'SET' or 'PREPEND', respectively, as
the first argument to <methodname>captureStart()</methodname>.
</para>
</listitem>
<listitem>
<para>
If you wish to specify any additional attributes for the
<emphasis><style></emphasis> tag, pass them in an array as
the second argument to <methodname>captureStart()</methodname>.
</para>
</listitem>
</itemizedlist>
</example>
</sect3>
<!--
vim:se ts=4 sw=4 et:
-->
|
