使用RecyclerView实现简易外卖购物车

看完郭霖的第一行代码，想用RecyclerView实现购物车功能，找了挺多资料的，终于完成了

/* AUTO-GENERATED FILE.  DO NOT MODIFY.
 *
 * This class was automatically generated by the
 * gradle plugin from the resource data it found. It
 * should not be modified by hand.
 */
package android.arch.core;

public final class R {
    private R（） {}

}

 属性            大小     日期    时间   名称
----------- ---------  ---------- -----  ----
     目录           0  2019-03-23 19:43  Recycler_gouwuche\
     文件         187  2019-03-23 10:10  Recycler_gouwuche\.gitignore
     目录           0  2019-03-23 10:10  Recycler_gouwuche\.gradle\
     目录           0  2019-03-23 10:24  Recycler_gouwuche\.gradle\4.6\
     目录           0  2019-03-23 10:10  Recycler_gouwuche\.gradle\4.6\fileChanges\
     文件           1  2019-03-23 19:51  Recycler_gouwuche\.gradle\4.6\fileChanges\last-build.bin
     目录           0  2019-03-23 10:24  Recycler_gouwuche\.gradle\4.6\fileContent\
     文件          17  2019-03-23 19:51  Recycler_gouwuche\.gradle\4.6\fileContent\fileContent.lock
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     文件      197601  2019-03-23 19:51  Recycler_gouwuche\.gradle\4.6\fileHashes\fileHashes.bin
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     文件      283841  2019-03-23 10:24  Recycler_gouwuche\.gradle\4.6\javaCompile\jarAnalysis.bin
     文件          17  2019-03-23 19:51  Recycler_gouwuche\.gradle\4.6\javaCompile\javaCompile.lock
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     目录           0  2019-03-23 10:10  Recycler_gouwuche\.gradle\buildOutputCleanup\
     文件          17  2019-03-23 19:51  Recycler_gouwuche\.gradle\buildOutputCleanup\buildOutputCleanup.lock
     文件          51  2019-03-23 10:10  Recycler_gouwuche\.gradle\buildOutputCleanup\cache.properties
     文件       20693  2019-03-23 19:51  Recycler_gouwuche\.gradle\buildOutputCleanup\outputFiles.bin
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     目录           0  2019-03-23 19:55  Recycler_gouwuche\.idea\
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     目录           0  2019-03-23 19:42  Recycler_gouwuche\.idea\codestyles\
............此处省略1563个文件信息