小编Doo*_*oom的帖子

可能重复:
IPhone应用程序中的复选框

我想创建一个带有2个值的简单复选框并保存,我该怎么做？

谢谢.

如何暂停我的申请或向我的申请发送暂停消息？

我想模拟按下主页按钮.

我想用Spring将File转换为multipartfile.我做了这个:

File in;
MultipartFile file =  null;
in = new File("C:...file on disk");
int size = (int) in.length();
DiskFileItem fileItem = new DiskFileItem("file", "application/vnd.ms-excel", false, nomefile, size ,in.getAbsoluteFile());
file = new CommonsMultipartFile(fileItem);

但收到此例外:

threw exception [Request processing failed; nested exception is java.lang.NullPointerException] with root cause
java.lang.NullPointerException
    at org.apache.commons.fileupload.disk.DiskFileItem.getSize(DiskFileItem.java:316)

我认为fileItem为null但是在填充调试模式时,还有另一种解决方案吗？我有这篇文章将文件转换为MultiPartFile但没有工作,没有解决方案.

我如何只比较2的年 - 月 - 日组件NSDates？

我有这个LinkedHashMap列表怎么可以订购值？

    List<LinkedHashMap<String, Object>> list = more "key:value"......

例如,在我的列表中,我有:

    [{"field1": "z", "field2":"a"},
     {"field1" : "b", "field2":"x"}]

我想要基于"field1"键的值的顺序,例如:

    [{"field1": "b", "field2":"x"},
     {"field1" : "z", "field2":"a"}]

我做了这堂课:

public class OrderComparator  implements Comparator {
    String field;

    public OrderComparator (String field){
        this.field = field;
    }

    @Override
    public int compare(Object obj1, Object obj2) {
          LinkedHashMap<String, Object> a = (LinkedHashMap<String, Object>) obj1;
          LinkedHashMap<String, Object> b = (LinkedHashMap<String, Object>) obj2;

          return a.get(this.field).toString().compareTo(b.get(this.field).toString());
    }   
}

并且:

Collections.sort(list, new OrderComparator(sortColumn));

是正确的？谢谢大家!!!