Android通过Intent传递ArrayList
我试图将数据从一个屏幕传递到另一个屏幕。第一个屏幕从CSV读取数据并将数据放入数据库表中。任何无效的数据（例如年份（整数）中的字符串）都会被捕获并存储在errorItem的ArrayList中，该ArrayList包含Book title，author，date，isbn，copies和tags。我的程序已经成功识别出无效的csv条目，但是当我传递要显示的错误数据时，listview只显示最后一个条目并重复它。
这可能是什么问题？
主要代码
ArrayList<itemLink> errorList = new ArrayList<itemLink>();
int successCounter = 0;
int errorCounter = 0;
String[][] errors = new String[1][6];
String[] line = new String[6];
try {
int titleCol = -1, authorCol = -1, dateCol = -1, isbnCol = -1, quantityCol = -1, tagCol = -1;
CSVReader reader = new CSVReader(new FileReader(new File(Environment.getExternalStorageDirectory().getPath()+location)));
String [] nextLine;
nextLine = reader.readNext();
int index = 0;
int lineLength = nextLine.length;
while(titleCol < 0 && index < lineLength)
{
if(nextLine[index].contains("TITLE"))
titleCol = index;
index++;
}
index = 0;
while(authorCol < 0 && index < lineLength)
{
if(nextLine[index].contains("AUTHOR"))
authorCol = index;
index++;
}
index = 0;
while(dateCol < 0 && index < lineLength)
{
if(nextLine[index].contains("DATE"))
dateCol = index;
index++;
}
index = 0;
while(isbnCol < 0 && index < lineLength)
{
if(nextLine[index].contains("ISBN"))
isbnCol = index;
index++;
}
index = 0;
while(quantityCol < 0 && index < lineLength)
{
if(nextLine[index].contains("COPIES"))
quantityCol = index;
index++;
}
index = 0;
while(tagCol < 0 && index < lineLength)
{
if(nextLine[index].contains("TAGS"))
tagCol = index;
index++;
}
System.out.println(nextLine[titleCol]);
System.out.println(nextLine[authorCol]);
System.out.println(nextLine[dateCol]);
System.out.println(nextLine[isbnCol]);
System.out.println(nextLine[quantityCol]);
System.out.println(nextLine[tagCol]);
int counter = 0;
while ((nextLine = reader.readNext()) != null) {
// nextLine[] is an array of values from the line
/*
* nextLine[titleCol] = TITLE
* nextLine[authorCol] = AUTHOR
* nextLine[dateCol] = DATE
* nextLine[isbnCol] = ISBN
* nextLine[quantityCol] = QUANTITY
* nextLine[tagCol] = TAGS
*/
lineLength = nextLine.length;
if(nextLine[isbnCol].contains("0") || nextLine[isbnCol].contains("1")
|| nextLine[isbnCol].contains("2") || nextLine[isbnCol].contains("3")
|| nextLine[isbnCol].contains("4") || nextLine[isbnCol].contains("5")
|| nextLine[isbnCol].contains("6") || nextLine[isbnCol].contains("7")
|| nextLine[isbnCol].contains("8") || nextLine[isbnCol].contains("9"))
{
if(InventoryAdapter.isbnFoundInInventory(nextLine[isbnCol]) == false)
{
if(nextLine[dateCol].contains("0") || nextLine[dateCol].contains("1")
|| nextLine[dateCol].contains("2") || nextLine[dateCol].contains("3")
|| nextLine[dateCol].contains("4") || nextLine[dateCol].contains("5")
|| nextLine[dateCol].contains("6") || nextLine[dateCol].contains("7")
|| nextLine[dateCol].contains("8") || nextLine[dateCol].contains("9"))
line[2] = nextLine[dateCol];
else
line[2]="-9999";
if(nextLine[quantityCol].contains("0") || nextLine[quantityCol].contains("1")
|| nextLine[quantityCol].contains("2") || nextLine[quantityCol].contains("3")
|| nextLine[quantityCol].contains("4") || nextLine[quantityCol].contains("5")
|| nextLine[quantityCol].contains("6") || nextLine[quantityCol].contains("7")
|| nextLine[quantityCol].contains("8") || nextLine[quantityCol].contains("9"))
line[4] = nextLine[quantityCol];
else
line[4]="-9999";
if(tagCol < lineLength && nextLine[tagCol].length() > 0)
line[5] = nextLine[tagCol];
else
line[5] = "*ERROR*";
if(titleCol < lineLength && nextLine[titleCol].length() > 0)
line[0] = nextLine[titleCol];
else
line[0] = "*ERROR*";
if(authorCol < lineLength && nextLine[authorCol].length() > 0)
line[1] = nextLine[authorCol];
else
line[1] = "*ERROR*";
if(isbnCol < lineLength && nextLine[isbnCol].length() > 0)
line[3] = nextLine[isbnCol];
else
line[3] = "*ERROR*";
if(line[0].equals("*ERROR*") || line[1].equals("*ERROR*")
|| line[3].equals("*ERROR*")|| line[5].equals("*ERROR*")
|| line[2].equals("-9999")|| line[4].equals("-9999"))
{
System.out.println(counter+". ERROR FOUND: "+line[0]);
errorList.add(new itemLink(line[0], line[1], Integer.parseInt(line[2]),
line[3], Integer.parseInt(line[4]), line[5]));
errorCounter++;
}
else
{
System.out.println(counter+". SUCCESSFULLY ADDED: "+line[0]);
InventoryAdapter.insertEntry(line[0], line[1], line[3], Integer.parseInt(line[2]),
line[5], Integer.parseInt(line[4]), 14);
successCounter++;
}
}
}
counter++;
}
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
progressDialog.dismiss();
Intent i=new Intent(InventorySyncScreen.this,SyncSuccessScreen.class);
i.putExtra("username",userName);
i.putExtra("numSuccess",successCounter);
i.putExtra("numError", errorCounter);
i.putExtra("errorList", errorList);
startActivity(i);
SyncSuccessScreen
Intent intent = getIntent();
final String userName = intent.getExtras().getString("username");
int numSuccess= intent.getExtras().getInt("numSuccess");
int numError= intent.getExtras().getInt("numError");
@SuppressWarnings("unchecked")
ArrayList<itemLink> errorList = (ArrayList<itemLink>) getIntent().getSerializableExtra("errorList");
textNumSuccess.setText("Items Successfully Synced: "+numSuccess);
textNumError.setText("Data Errors Found: "+numError);
// Set up array
String[] errors = new String[6];
for(int i = 0; i < errorList.size(); i++)
{
System.out.println("errors[0] = "+errors[0]);
errors[0] = errorList.get(i).title;
errors[1] = errorList.get(i).author;
errors[2] = ((Integer)errorList.get(i).date).toString();
errors[3] = errorList.get(i).isbn;
errors[4] = ((Integer)errorList.get(i).quantity).toString();
errors[5] = errorList.get(i).tags;
reportArray.add(new ErrorItem(i, errors));
}
// add data in custom adapter
errorAdapter = new CustomErrorAdapter(this, R.layout.errorlist_row, reportArray);
ListView dataList = (ListView) findViewById(R.id.errorlist_row);
dataList.setAdapter(errorAdapter);
CustomErrorAdapter
public class CustomErrorAdapter extends ArrayAdapter<ErrorItem> {
Context context;
int layoutResourceId;
LinearLayout linearMain;
ArrayList<ErrorItem> data = new ArrayList<ErrorItem>();
public CustomErrorAdapter(Context context, int layoutResourceId,
ArrayList<ErrorItem> data) {
super(context, layoutResourceId, data);
this.layoutResourceId = layoutResourceId;
this.context = context;
this.data = data;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
View row = null;
if (convertView == null) {
LayoutInflater inflater = ((Activity) context).getLayoutInflater();
row = inflater.inflate(layoutResourceId, parent, false);
//Make sure the textview exists in this xml
} else {
row = convertView;
}
ErrorItem myItem = data.get(position);
TextView titleLabel = (TextView) row.findViewById(R.id.titleText);
titleLabel.setText(myItem.details[0]);
TextView authorLabel = (TextView) row.findViewById(R.id.authorText);
authorLabel.setText(myItem.details[1]);
TextView dateLabel = (TextView) row.findViewById(R.id.dateText);
dateLabel.setText(myItem.details[2]);
TextView isbnLabel = (TextView) row.findViewById(R.id.isbnText);
isbnLabel.setText(myItem.details[3]);
TextView copiesLabel = (TextView) row.findViewById(R.id.copiesText);
copiesLabel.setText(myItem.details[4]);
TextView tagLabel = (TextView) row.findViewById(R.id.tagText);
tagLabel.setText(myItem.details[5]);
if(myItem.details[5].equals("*ERROR*"))
tagLabel.setTextColor(Color.parseColor("#ff2626"));
if(myItem.details[2].equals("-9999"))
dateLabel.setTextColor(Color.parseColor("#ff2626"));
if(myItem.details[4].equals("-9999"))
copiesLabel.setTextColor(Color.parseColor("#ff2626"));
if(myItem.details[0].equals("*ERROR*"))
titleLabel.setTextColor(Color.parseColor("#ff2626"));
if(myItem.details[1].equals("*ERROR*"))
authorLabel.setTextColor(Color.parseColor("#ff2626"));
if(myItem.details[3].equals("*ERROR*"))
isbnLabel.setTextColor(Color.parseColor("#ff2626"));
return row;
}
}
错误项
public class ErrorItem {
public int num;
public String[] details;
public ErrorItem(int num, String[] details) {
super();
this.details = details;
}
public int getNum() {
return num;
}
public void setNum(int num) {
this.num = num;
}
public String[] getDetails() {
return details;
}
public void setDetails(String[] details) {
this.details = details;
}
}
日志显示 日志显示ArrayList正在正确传递到SyncSuccessScreen。
01-22 01:42:51.327: I/System.out(8717): errors[0] = *ERROR*
01-22 01:42:51.327: I/System.out(8717): errors[0] = The big beautiful
01-22 01:42:51.327: I/System.out(8717): errors[0] = Pieces of my sister's life
4 个答案:
答案 0 :(得分：3)
你必须在类Itemlink上实现serialisable，并且必须从getintent().getserialisableExtra()
例如：
public class Itemlink implements Serializable{
} 将值传递为
intent.putExtra("key",value);
getvalue as `getintent().getSerilaziable.Extra("key")`
答案 1 :(得分：2)
当您需要传达自定义对象（例如ErrorItem）时，自定义对象必须实现Parcelable或Serializable
class ErrorItem implements Parcelable{
检查this
答案 2 :(得分：1)
错误发生在SyncSuccessScreen
中errors[0] = errorList.get(i).title;
errors[1] = errorList.get(i).author;
errors[2] = ((Integer)errorList.get(i).date).toString();
errors[3] = errorList.get(i).isbn;
errors[4] = ((Integer)errorList.get(i).quantity).toString();
errors[5] = errorList.get(i).tags;
reportArray.add(new ErrorItem(i, errors));
应该声明String []错误的新实例，否则每个ErrorItem引用相同的String []错误，并且更改其中一个会影响每个ErrorItem。
<强>正确：
String[] errors = new String[6];
for(int i = 0; i < errorList.size(); i++)
{
errors = new String[6]; //add this
errors[0] = errorList.get(i).getTitle();
errors[1] = errorList.get(i).getAuthor();
errors[2] = ((Integer)errorList.get(i).getDate()).toString();
errors[3] = errorList.get(i).getISBN();
errors[4] = ((Integer)errorList.get(i).getQuantity()).toString();
errors[5] = errorList.get(i).getTags();
reportArray.add(i, new ErrorItem(i, errors));
}
答案 3 :(得分：0)
让你的ErrorItem实现Serializable
public class ErrorItem implements Serializable{
并在您的意图中更改此行： i.putExtra（“errorList”，errorList）; 至 i.putSerializableExtra（ “errorList”，errorList）;
然后得到它：
ArrayList errorList =（ArrayList）getIntent（）。getSerializableExtra（“errorList”）;
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