HashMap的值不被追加到的ListView [英] HashMap values not being appended to ListView

问题描述

我想要检索与多个值HashMap的数据，1项并将其设置为一个列表视图，但是设置，而不是值 进入列表视图，并显示在列表视图，所有这一切都显示是数组（无钥匙）。 在code是如下：

i'm trying to retrieve data from a hashmap with multiple values for 1 key and set it to a listview,but instead of setting the values into the listview and displaying the listview,all that is displayed is the array(without the key). The code is as follows:

ListView lv = (ListView)findViewById(R.id.list);
    //hashmap of type  `HashMap<String, List<String>>`
    HashMap<String, List<String>> hm = new HashMap<String, List<String>>();
    List<String> values = new ArrayList<String>();
    for (int i = 0; i < j; i++) {
        values.add(value1);
        values.add(value2);
        hm.put(key, values);
    }

和检索值，并把在ListView

and to retrieve the values and put in a listview

ListAdapter adapter = new SimpleAdapter(
                        MainActivitty.this,  Arrays.asList(hm),
                        R.layout.list_item, new String[] { key,
                                value1,value2},
                        new int[] { R.id.id, R.id.value1,R.id.value2 });
                // updating listview
                lv.setAdapter(adapter);

一个例子是，其中的关键= 1，值2 = 2和值3 = 3，它会显示一个数组，看起来像[2,3]。 我如何得到它显示lisview并添加关键吗？

an example is where the key=1,value2=2 and value3=3,it will display the an array that looks like [2,3]. how do i get it to display the lisview and add the key too?

推荐答案

SimpleAdapters Consturctor状态，因为它的第二个参数：

SimpleAdapters Consturctor states as it's second parameter:

数据：地图列表。在列表中的每个条目对应于一个行中的   列表。所述地图包含每个行的数据，并应包括   所有，从中指定的条目

data: A List of Maps. Each entry in the List corresponds to one row in the list. The Maps contain the data for each row, and should include all the entries specified in "from"

但的HashMap＆LT;字符串列表与LT;字符串＆GT;＆GT; HM是列表的图。因此，像名单，其中，地图＆LT;字符串，字符串＆GT;＆GT; HM 将是你可能需要的数据类型。

but HashMap<String, List<String>> hm is a map of lists. So like List<Map<String,String>> hm would be the datatype you probably need.

下面是经过编辑的源：

 ListView lv = (ListView)findViewById(R.id.list);
            List<Map<String,String>> mapList = new ArrayList<Map<String, String>>();
            Map<String,String> mapPerRow;
            for (int i = 0; i < rowNumbers; i++) {
                mapPerRow = new HashMap<String, String>();
                mapPerRow.put("column1", value1);
                mapPerRow.put("column2", value2);

                mapList.add(mapPerRow);
            }


            ListAdapter adapter = new SimpleAdapter(
                    MainActivitty.this,  mapList,
                    R.layout.list_item, new String[] { "column1", "colum2"},
                    new int[] { R.id.value1,R.id.value2 });
            // updating listview
            lv.setAdapter(adapter);

我不知道为什么你要在它（只需添加字符串到地图，如果你需要更多的）的关键？

I don't get why you want the key in it (just add Strings to the map if you need more)?

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