我正在尝试在我的活动中创建一个ExpandableListView，显示顶级葡萄酒的类型，以及二级葡萄酒的单瓶装。我正在从我创建的CSV文件中读取我的所有数据，并填充了8个特定的葡萄酒瓶，这些葡萄酒现在属于一个类别。我遇到了一个问题，我正在将我的数据从csv文件读入一个数组，我可以在读取它时将其报告给日志，并且它显示正确。但是一旦我尝试将它放入我的适配器然后进入listview，数组就会填充8个相同的Wine对象，这些对象就是我文件中的最后一个。
以下是我用来读取文件并创建Wine对象数组的代码。
编辑：在while循环完成填充之后，我更改了代码以检查我的数组写入，并得到相同的结果。这是代码的较新版本。
handler = new Handler()
{
@Override
public void handleMessage(Message msg)
{
Log.i(myTag, "Notify Change");
//By the time I get to here every object in the array is identical
for(int i = 0; i < chrd.length; i++){
Log.i(myTag,i + " " + chrd[i].toString());
}
super.handleMessage(msg);
}
};
Runnable r = new Runnable(){
public void run()
{
current = new Chardonnay();
//final int ITEMS = 15;
int count = 0;
try {
File myFile = new File ("/sdcard/chardonnay.txt");
fis = new FileInputStream(myFile);
BufferedReader reader = new BufferedReader(new InputStreamReader(fis));
String line;
while ((line = reader.readLine()) != null) {
String[] RowData = line.split(",");
current.setName(RowData[0]);
current.setPlace(RowData[1]);
current.setDescription(RowData[2]);
current.setYear(Integer.valueOf(RowData[3]));
current.setPriceBottle(Integer.valueOf(RowData[4]));
current.setPriceGlass(Integer.valueOf(RowData[5]));
chrd[count] = current;
Log.i(myTag, count + " " + chrd[count]);
count++;
}
for(int i = 0; i < chrd.length; i++){
Log.i(myTag,i + " " + chrd[i]);
}
}
catch (IOException ex) {
// handle exception
ex.printStackTrace();
}
handler.sendEmptyMessage(1);
try {
fis.close();
}
catch (IOException e) {
e.printStackTrace();
}
}
};
Thread thread = new Thread(r);
thread.start();
}
以下是运行此命令的日志输出：
04-13 15:45:09.390: INFO/One2OneWineMenu(6472): 0 Wine [name=Acre, place=Central Coast, description=Seductive apple pie crust and lemon blossom aromas introduce crisp juicy flavors enriched by a creaminess resulting from surlie barrel aging, year=2008, priceBottle=25, priceGlass=7]
04-13 15:45:09.390: INFO/One2OneWineMenu(6472): 1 Wine [name=Silver Palm, place=North Coast, description=Fermented in stainless steel* this wine's delicate fruit characteristics were preserved without any overbearing flavors that an oak barrel might impart, year=2009, priceBottle=30, priceGlass=10]
04-13 15:45:09.390: INFO/One2OneWineMenu(6472): 2 Wine [name=Franciscan, place=Napa Valley, description=Ripe* generous aromas of apple* pear* and honey with toasty oak. Lively* rich creamy and supple with notes of vanilla on the finish, year=2009, priceBottle=30, priceGlass=-1]
04-13 15:45:09.390: INFO/One2OneWineMenu(6472): 3 Wine [name=Sonoma Cutrer, place=Russian River, description=The 2nd most popular chardonnay in W&S Restaurant Poll* this wine is beautifully balanced with well integrated oak, year=2008, priceBottle=35, priceGlass=11]
04-13 15:45:09.390: INFO/One2OneWineMenu(6472): 4 Wine [name=Matanzas Creek, place=Sonoma, description=92 pts WE* this wine has a silky texture with flavors of lemon cream* peach and pear which feels elegant and creamy on the palate, year=2007, priceBottle=40, priceGlass=-1]
04-13 15:45:09.390: INFO/One2OneWineMenu(6472): 5 Wine [name=Silver by Mer Soleil, place=Santa Lucia Highlands, description=Combines ripe* intense peach* nectarine and tangerine fruit with touches of floral and spice, year=2007, priceBottle=40, priceGlass=-1]
04-13 15:45:09.390: INFO/One2OneWineMenu(6472): 6 Wine [name=Jordan, place=Russian River, description=Voted Best Chardonnay by respected wine journalists who attended 2010 Critics Challenge, year=2008, priceBottle=50, priceGlass=-1]
04-13 15:45:09.390: INFO/One2OneWineMenu(6472): 7 Wine [name=Ramey, place=Santa Lucia Highlands, description=94 pts RP* intense and vibrant* shows full-bodied citrus* melon* and hazelnut flavors that turn subtle and offer hints of fig/tangerine, year=2007, priceBottle=90, priceGlass=-1]
04-13 15:45:09.405: INFO/One2OneWineMenu(6472): Notify Change
04-13 15:45:09.405: INFO/One2OneWineMenu(6472): 0 Wine [name=Ramey, place=Santa Lucia Highlands, description=94 pts RP* intense and vibrant* shows full-bodied citrus* melon* and hazelnut flavors that turn subtle and offer hints of fig/tangerine, year=2007, priceBottle=90, priceGlass=-1]
04-13 15:45:09.405: INFO/One2OneWineMenu(6472): 1 Wine [name=Ramey, place=Santa Lucia Highlands, description=94 pts RP* intense and vibrant* shows full-bodied citrus* melon* and hazelnut flavors that turn subtle and offer hints of fig/tangerine, year=2007, priceBottle=90, priceGlass=-1]
04-13 15:45:09.405: INFO/One2OneWineMenu(6472): 2 Wine [name=Ramey, place=Santa Lucia Highlands, description=94 pts RP* intense and vibrant* shows full-bodied citrus* melon* and hazelnut flavors that turn subtle and offer hints of fig/tangerine, year=2007, priceBottle=90, priceGlass=-1]
04-13 15:45:09.405: INFO/One2OneWineMenu(6472): 3 Wine [name=Ramey, place=Santa Lucia Highlands, description=94 pts RP* intense and vibrant* shows full-bodied citrus* melon* and hazelnut flavors that turn subtle and offer hints of fig/tangerine, year=2007, priceBottle=90, priceGlass=-1]
04-13 15:45:09.405: INFO/One2OneWineMenu(6472): 4 Wine [name=Ramey, place=Santa Lucia Highlands, description=94 pts RP* intense and vibrant* shows full-bodied citrus* melon* and hazelnut flavors that turn subtle and offer hints of fig/tangerine, year=2007, priceBottle=90, priceGlass=-1]
04-13 15:45:09.405: INFO/One2OneWineMenu(6472): 5 Wine [name=Ramey, place=Santa Lucia Highlands, description=94 pts RP* intense and vibrant* shows full-bodied citrus* melon* and hazelnut flavors that turn subtle and offer hints of fig/tangerine, year=2007, priceBottle=90, priceGlass=-1]
04-13 15:45:09.405: INFO/One2OneWineMenu(6472): 6 Wine [name=Ramey, place=Santa Lucia Highlands, description=94 pts RP* intense and vibrant* shows full-bodied citrus* melon* and hazelnut flavors that turn subtle and offer hints of fig/tangerine, year=2007, priceBottle=90, priceGlass=-1]
04-13 15:45:09.405: INFO/One2OneWineMenu(6472): 7 Wine [name=Ramey, place=Santa Lucia Highlands, description=94 pts RP* intense and vibrant* shows full-bodied citrus* melon* and hazelnut flavors that turn subtle and offer hints of fig/tangerine, year=2007, priceBottle=90, priceGlass=-1]
我尝试过相同的逻辑概念但使用ArrayList而不是Wine []并且它有同样的问题。我很难过，我从未见过数组的内容只是因为没有明显的原因而改变了。也许我忽略了一些相对简单的事情，有没有人知道这里会发生什么？
答案 0 :(得分：1)
您将同一个对象（current）分配给chrd的所有单元格，这就是您最后得到最后一个值的原因。您应该在循环内初始化current以解决此问题。
while ((line = reader.readLine()) != null) {
current = new Chardonnay();
String[] RowData = line.split(",");
current.setName(RowData[0]);
current.setPlace(RowData[1]);
current.setDescription(RowData[2]);
current.setYear(Integer.valueOf(RowData[3]));
current.setPriceBottle(Integer.valueOf(RowData[4]));
current.setPriceGlass(Integer.valueOf(RowData[5]));
chrd[count] = current;
Log.i(myTag, count + " " + chrd[count]);
count++;
}
答案 1 :(得分：1)
问题出在这一行：
current = new Chardonnay();
您只创建一个对象，while的每个循环都会替换此对象中的属性，因此您将以最后一个对象结束。
在while循环中移动对象的创建。
答案 2 :(得分：1)
move“current = new Chardonnay（）;”到while循环
在您的代码中，数组中的每个项目都指向Chardonnay的同一个实例
答案 3 :(得分：0)
根据我的经验，这就是我必须格式化ExpandableListAdapter组的数据：
ArrayList<HashMap<String, String>> alist = new ArrayList<HashMap<String, String>>();
...
//provided there are entries in the database, iterate through them all. create a hashmap using "company" as the key and
//the company as the item and add this hashmap to the array of maps.
if (cursor.moveToFirst()) {
do {
HashMap<String, String> m = new HashMap<String, String>();
m.put("company", cursor.getString(cursor.getColumnIndex(CompanyAndProductDatabaseAdapter.company_column)));
alist.add(m);
} while (cursor.moveToNext());
}