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关于安卓通过webservice访问数据库问题
问题描述：
访问数据库时，手机能增删数据库的数据就是显示不了数据库的里的数据不知道是哪里的问题，用的HTTP
这是我webservice中的产看所有信息的方法：
public List<string> selectAllCargoInfor() { List<string> list = new List<string>(); try { string sql = "select * from C"; SqlCommand cmd = new SqlCommand(sql,sqlCon); SqlDataReader reader = cmd.ExecuteReader(); while (reader.Read()) { //将结果集信息添加到返回向量中 list.Add(reader[0].ToString()); list.Add(reader[1].ToString()); list.Add(reader[2].ToString()); } reader.Close(); cmd.Dispose(); } catch(Exception) { } return list; }
接下来是安卓端的：
这个是MainActivity中的设置LISTVIEW的方法
private void setListView() { listView.setVisibility(View.VISIBLE); List<HashMap<String, String>> list = new ArrayList<HashMap<String, String>>(); list = dbUtil.getAllInfo(); adapter = new SimpleAdapter(MainActivity.this, list, R.layout.adapter_item, new String[] { "Cno", "Cname", "Cnum" }, new int[] { R.id.txt_Cno, R.id.txt_Cname, R.id.txt_Cnum }); listView.setAdapter(adapter); }
这个是操作类：
public List<HashMap<String, String>> getAllInfo() { List<HashMap<String, String>> list = new ArrayList<HashMap<String, String>>(); arrayList.clear(); brrayList.clear(); crrayList.clear(); new Thread(new Runnable() { @Override public void run() { // TODO Auto-generated method stub crrayList = Soap.GetWebServre("selectAllCargoInfor", arrayList, brrayList); } }).start(); HashMap<String, String> tempHash = new HashMap<String, String>(); tempHash.put("Cno", "Cno"); tempHash.put("Cname", "Cname"); tempHash.put("Cnum", "Cnum"); list.add(tempHash); for (int j = 0; j < crrayList.size(); j += 3) { HashMap<String, String> hashMap = new HashMap<String, String>(); hashMap.put("Cno", crrayList.get(j)); hashMap.put("Cname", crrayList.get(j + 1)); hashMap.put("Cnum", crrayList.get(j + 2)); list.add(hashMap); } return list; }
连接webservice的那个方法HttpConnSoap应该是没问题的因为数据库的增删都是可以的，就是无法实现这个显示所有信息到LISTVIEW中的这个功能不知道为什么，LOGCAT中也是一片绿没什么问题
LOGCAT中的信息：
05-02 15:51:40.642: I/System.out(3678): <?xml version="1.0" encoding="utf-8"?><soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"><soap:Body><selectAllCargoInforResponse xmlns="http://tempuri.org/"><selectAllCargoInforResult><string>1</string><string>rice</string><string>100</string><string>2</string><string>dog</string><string>50</string><string>3</string><string>白痴</string><string>25</string></selectAllCargoInforResult></selectAllCargoInforResponse></soap:Body></soap:Envelope>
05-02 15:51:40.647: I/System.out(3678): <?xml version="1.0" encoding="utf-8"?
05-02 15:51:40.647: I/System.out(3678): soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"
05-02 15:51:40.647: I/System.out(3678): soap:Body
05-02 15:51:40.647: I/System.out(3678): selectAllCargoInforResponse xmlns="http://tempuri.org/"
05-02 15:51:40.647: I/System.out(3678): selectAllCargoInforResult
05-02 15:51:40.647: I/System.out(3678): 0
05-02 15:51:40.647: I/System.out(3678): string>1</string
05-02 15:51:40.647: I/System.out(3678): string>rice</string
05-02 15:51:40.647: I/System.out(3678): string>100</string
05-02 15:51:40.647: I/System.out(3678): string>2</string
05-02 15:51:40.652: I/System.out(3678): string>dog</string
05-02 15:51:40.652: I/System.out(3678): string>50</string
05-02 15:51:40.652: I/System.out(3678): string>3</string
05-02 15:51:40.652: I/System.out(3678): string>白痴</string
05-02 15:51:40.652: I/System.out(3678): string>25</string
05-02 15:51:40.652: I/System.out(3678): /selectAllCargoInforResult
05-02 15:51:40.652: I/System.out(3678): 1
解决方案1：
分析原因就是在线程还没有执行完时候，getAllInfo早已执行完毕以后，，所以在执行for (int j = 0; j < crrayList.size(); j += 3)时候， crrayList为零行。你取出的LOGCAT是执行请求以后的返回数据，这时候setListView方法早已经走完，所以只有一行数据。截图中的一行数据来自
HashMap<String, String> tempHash = new HashMap<String, String>();
tempHash.put("Cno", "Cno");
tempHash.put("Cname", "Cname");
tempHash.put("Cnum", "Cnum");
list.add(tempHash);
使用Thread应该配合Handler来使用。
我把代码修改一下
private final static int REQUEST_SUCCESS = 1; private final static int REQUEST_FALSE = 0; private void RequestData() { arrayList.clear(); brrayList.clear(); crrayList.clear(); new Thread(new Runnable() { @Override public void run() { // TODO Auto-generated method stub crrayList = Soap.GetWebServre("selectAllCargoInfor", arrayList, brrayList); Message msg = new Message(); if(crrayList.size()>0) { msg.what = REQUEST_SUCCESS; } else { msg.what = REQUEST_FALSE; } // 发送消息 mHandler.sendMessage(msg); } }).start(); } public Handler mHandler = new Handler(){ // 接收消息 @Override public void handleMessage(Message msg) { // TODO Auto-generated method stub super.handleMessage(msg); switch (msg.what) { case REQUEST_SUCCESS: setListView(); break; case REQUEST_FALSE: // 做错误处理 break; default: break; } } }; private void setListView() { listView.setVisibility(View.VISIBLE); List<HashMap<String, String>> list = new ArrayList<HashMap<String, String>>(); list = dbUtil.getAllInfo(); adapter = new SimpleAdapter(MainActivity.this, list, R.layout.adapter_item, new String[] { "Cno", "Cname", "Cnum" }, new int[] { R.id.txt_Cno, R.id.txt_Cname, R.id.txt_Cnum }); listView.setAdapter(adapter); } public List<HashMap<String, String>> getAllInfo() { List<HashMap<String, String>> list = new ArrayList<HashMap<String, String>>(); HashMap<String, String> tempHash = new HashMap<String, String>(); tempHash.put("Cno", "Cno"); tempHash.put("Cname", "Cname"); tempHash.put("Cnum", "Cnum"); list.add(tempHash); for (int j = 0; j < crrayList.size(); j += 3) { HashMap<String, String> hashMap = new HashMap<String, String>(); hashMap.put("Cno", crrayList.get(j)); hashMap.put("Cname", crrayList.get(j + 1)); hashMap.put("Cnum", crrayList.get(j + 2)); list.add(hashMap); } return list; }
执行RequestData就可以，我没法编译，细节自己再调整看一下，应该能解决问题了。
你给的分数太少了，大牛们都不给你解答。如果解决问题就给分哈。
另外，Java多线程的操作可以系统学习一下。工作中使用极为频繁。
关于安卓通过webservice访问数据库问题