以前学习shell脚本语言时写的一个小脚本，可以一步添加一个文件夹里的特定格式的图片为系统的动态壁纸，也可以根据指定的标签删除创建的动态壁纸
适合gnome环境
命令帮助如下：
xml.sh [-dsth] [time] [Directory]  [标签]
         -d Dir                包含有壁纸的目录
         -s time               壁纸静态时间(s),默认1790.0 s
         -t time               壁纸切换时间(s),默认2.0 s
         -r [itm1 itm2 ...]    根据指定的动态壁纸的标签，删除动态壁纸的信息,默认标签为目录的名字
         -h                    打印帮助
例如有一文件夹/home/zhang/picture下有若干图片，想把它们添加为动态壁纸，标签设为gnome,可如下执行：
xml.sh -d /home/zhang/picture gnome
指定壁纸静态保持的时间和壁纸间切换的时间
xml.sh -s 100 -t 5 -d /home/zhang/picture gnome
若执行 xml.sh，默认搜索当前目录下的图片并以目录名（非绝对路径）为标签建立动态壁纸信息
删除动态壁纸信息，这需要知道壁纸标签名，可同时指定多个标签
xml.sh -r gnome ...
此脚本只是练习，如有错误，恳请批评指教

#!/bin/bash
#Progam  :
#          1、将一个文件夹下的特定格式的图片组成一组动态壁纸,然后应用到系统
#          2、根据指定的文件夹从系统删除对应的动态壁纸信息(并不删除图片) 

#Data    :2013-09-08
#Author  :Juson
#Release :3rd Release
#Operating System :Fedora/Ubuntu Gnome环境 (其余未测试)


directory=`pwd`
filename=""
deldir=""
osdir="/usr/share/gnome-background-properties"
STATICTIME=1790.0   #壁纸静态时间(s)
TRANSTIME=2.0       #壁纸间切换时间(s)

####处理参数####
while [ -n "$1" ]
do
    if [ "$1" == "-h" ]; then
        echo "Usage: $0 [-dsth] [time] [Directory] [标签]"
        echo "         -d Dir                包含有壁纸的目录"
        echo "         -s time               壁纸静态时间(s),默认$STATICTIME s"
        echo "         -t time               壁纸切换时间(s),默认$TRANSTIME s"
        echo "         -r [itm1 itm2 ...]    根据指定的动态壁纸的标签，删除动态壁纸的信息,默认标签为目录的名字"
        echo "         -h                    打印帮助"
    exit 1
    elif [ "$1" == "-s" ]; then
        if [[ "$2" =~ ^[0-9]+\.?[0-9]*$ ]]; then
            STATICTIME=$2

            shift
        else
            echo "Error ：壁纸静态时间必须是有效数字"
            exit 2

        fi
    elif [ "$1" == "-t" ]; then
        if [[ "$2" =~ ^[0-9]+\.?[0-9]*$ ]]; then
            TRANSTIME=$2
            shift
        else
            echo "Error ：壁纸切换时间必须是有效数字"
            exit 3

        fi
    elif [ "$1" == "-d" ]; then
        directory=$2
        shift
    elif [ "$1" == "-r" ]; then
        shift
        deldir=$@
        if [ -z "$deldir" ]; then
            echo "Error :未指定要删除的标签"
            exit

        else
            break
        fi
    else

        filename=$1.xml
    fi


    shift
done


####删除动态壁纸信息####
if [ -n "$deldir" ]; then
    for dir in $deldir
    do
        if [[ "$dir" =~ \/ ]]; then
            echo "$dir 不是有效标签"
        else
            echo "正在删除动态壁纸$dir的信息..."
            sudo rm -rf $osdir/*$dir-wallpapers.xml
            if [ "$?" == "0" ]; then
                echo "已经成功删除动态壁纸$dir的信息"
            else
                echo "删除失败!!!"

            fi
        fi
    done
    exit

fi

####建立动态壁纸信息####
directory=${directory%/}
if [ ! -d "$directory" ]; then
     echo "Error :$directory 不是目录."
     exit 4
fi

if [ -z "$filename" ]; then
    filename="${RANDOM}_${directory##*/}.xml"
fi


rm $filename 2> /dev/null
touch $filename
if [ "$?" != "0" ]; then
    echo "Error :无法创建文件$filename"
    exit 5
fi


#下面仅仅搜索jpg、jpeg、png三种常用格式的图片，如有其他格式的图片可以按照下面的形式自己添加
firstfile=`ls -l $directory | egrep -i *.'(jpg|jpeg|png)$' | awk 'NR==1 { print $9 }'`
notfirst=`ls -l $directory | egrep -i *.'(jpg|jpeg|png)$' | awk 'NR!=1 { print $9 }'`

##判断是否有图片文件
if [ -z "$firstfile" ]; then
    echo "Error :Don't find any pictures in $directory"
    rm $filename 2> /dev/null
    exit 4

fi

wallpaperfilename="${filename%.*}-wallpapers.xml"

cat > $filename << EOF
<background>
  <starttime>
    <year>2013</year>
    <month>03</month>
    <day>29</day>
    <hour>00</hour>
    <minute>00</minute>
    <second>00</second>
  </starttime>
<!-- This animation will start at anytime. -->
  <static>
    <duration>$STATICTIME</duration>
    <file>$directory/$firstfile</file>
  </static>
  <transition>
    <duration>$TRANSTIME</duration>
    <from>$directory/$firstfile</from>
EOF

cat > $wallpaperfilename << EOF
<?xml version="1.0" encoding="UTF-8"?>
<!-- DOCTYPE wallpapers SYSTEM "gnome-wp-list.dtd" -->
<wallpapers>
 <wallpaper deleted="false">
  <name>${filename%.*}</name>
  <filename>$directory/$filename</filename>
  <options>zoom</options>
 </wallpaper>
EOF

for i in $notfirst
do
cat >> $filename << EOF
    <to>$directory/$i</to>
  </transition>
  <static>
    <duration>$STATICTIME</duration>
    <file>$directory/$i</file>
  </static>
  <transition>
    <duration>$TRANSTIME</duration>
    <from>$directory/$i</from>
EOF

cat >> $wallpaperfilename << EOF
 <wallpaper>
  <name>${i%.*}</name>
  <filename>$directory/$i</filename>
  <options>zoom</options>
  <pcolor>#000000</pcolor>
  <scolor>#000000</scolor>
  <shade_type>solid</shade_type>
 </wallpaper>
EOF
done

cat >> $filename << EOF
    <to>$directory/$firstfile</to>
  </transition>
</background>
EOF

cat >> $wallpaperfilename << EOF
</wallpapers>
EOF

####将壁纸信息应用到系统####
echo 正在使壁纸信息生效...
mv $filename $directory
sudo mv $wallpaperfilename $osdir

if [ "$?" == "0" ]; then
    echo "操作成功。"
else
    echo "未添加壁纸信息，操作失败。"
fi

exit 0