<doc>
  <legacy_id>2511</legacy_id>
  <name>backdrop</name>
  <type>property</type>
  <syntax>
    <example>set the backdrop to {<i>colorName</i> |<i> RGBColor</i> | <i>patternNumber</i> | <i>imageID</i> | none}</example>
  </syntax>
  <library></library>
  <objects>
    <global/>
  </objects>
  <synonyms>
  </synonyms>
  <classification>
    <category>Appearance &amp; Positioning</category>
    <category>The System Environment</category>
  </classification>
  <references>
    <function tag="clickStack">clickStack Function</function>
    <message tag="mouseUpInBackdrop">mouseUpInBackdrop Message</message>
    <property tag="raiseWindows">raiseWindows Property</property>
  </references>
  <history>
    <introduced version="1.0">Added.</introduced>
    <changed version="1.1"></changed>
  </history>
  <platforms>
    <mac/>
    <windows/>
    <linux/>
  </platforms>
  <classes>
    <desktop/>
  </classes>
  <security>
  </security>
  <summary>Places a solid or patterned <object tag="group">background</object> behind the <glossary tag="application">application's</glossary> windows, hiding any other applications.</summary>
  <examples>
    <example>set the backdrop to "black"</example>
    <example>set the backdrop to "140,30,30"</example>
    <example>set the backdrop to none <i>-- removes the backdrop</i></example>
  </examples>
  <description>
    <p>Use the <b>backdrop</b> <glossary tag="property">property</glossary> to create a kiosk mode, or to limit distractions during a movie or similar presentation.</p><p/><p><b>Value:</b></p><p>The <b>backdrop</b> is a <href tag="reference/color_reference.rev">color reference</href> or a pattern specifier.</p><p/><p>The <i>colorName</i> is any standard color name.</p><p/><p>The <i>RGBColor</i> consists of three comma-separated <glossary tag="integer">integers</glossary> between zero and 255, specifying the level of each of red, green, and blue; or an HTML-style color consisting of a hash mark (#) followed by three <glossary tag="hexadecimal">hexadecimal</glossary> numbers, one for each of red, green, and blue.</p><p/><p>A <i>patternNumber</i> is a built-in pattern number between 1 and 164. (These patterns correspond to LiveCode's built-in patterns 136 to 300.)</p><p/><p>An <i>imageID</i> is the ID of an <keyword tag="image">image</keyword> to use for a pattern. LiveCode looks for the specified <keyword tag="image">image</keyword> first in the <glossary tag="current stack">current stack</glossary>, then in other open <function tag="stacks">stacks</function>.</p><p/><p>By default, the <b>backdrop</b> is "none".</p><p/><p><b>Comments:</b></p><p>Hiding other applications from the user is usually not recommended, since users may need or want to see other windows on their system. However, the ability to do this can be very useful for some applications (such as kiosk systems or games) or at times when you want to reduce distractions (such as during the playing of a movie).</p><p/><p>Setting the <b>backdrop</b> <glossary tag="property">property</glossary> to "none" eliminates the backdrop and lets other windows be seen.</p><p/><p>Pattern images can be color or black-and-white.</p><p/><p><img src="202652"/> <b>Cross-platform note:</b> To be used as a pattern on <glossary tag="Mac OS">Mac OS systems</glossary>, an <keyword tag="image">image</keyword> must be 128x128 <property tag="pixels">pixels</property> or less, and both its <property tag="height">height</property> and <property tag="width">width</property> must be a power of 2. To be used on <function tag="openStacks">Windows</function> and <glossary tag="Unix">Unix systems</glossary>, <property tag="height">height</property> and <property tag="width">width</property> must be divisible by 8. To be used as a fully cross-platform pattern, both an image's dimensions should be one of 8, 16, 32, 64, or 128.</p><p/><p><img src="202652"/> <b>Cross-platform note:</b> On <glossary tag="Mac OS">Mac OS systems</glossary>, if you use the <command tag="launch">launch</command> or <command tag="open process">open process</command> <glossary tag="command">commands</glossary> to start up another application, or if the user brings another application to the front, its windows appear in front of the backdrop. (The backdrop remains visible even if the <glossary tag="application">application</glossary> is in the background.) Bringing the <glossary tag="application">application</glossary> to the front again hides the other application behind the backdrop. On <glossary tag="Unix">Unix</glossary> and <glossary tag="Windows">Windows systems</glossary>, any windows you open after setting the <b>backdrop</b> <glossary tag="property">property</glossary> remain in front of the backdrop, even if they belong to an application that is in the <object tag="group">background</object>.</p><p/><p>If the system has multiple screens connected, the <b>backdrop</b> <glossary tag="property">property</glossary> affects only the main screen.</p><p/><p><b>Changes:</b></p><p>The backdrop pattern option was introduced in version 1.1. In previous versions, the backdrop could be a solid color, but not a pattern.</p>
  </description>
</doc>