我有以下Android代码，其中Android应用程序联系Socket程序并在线程模型中获得结果为“SUCCESS”。之后，尝试显示警告对话框，但android程序获取异常为thread exiting with uncaught exception
我不知道这里有什么问题。我不能在线程中显示警报吗？请指教。
public class RandomIDActivity extends Activity {
.............
clientthread = new ClientThread();
Button connectBtn = (Button) findViewById(R.id.button2);
connectBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Thread t = new Thread(new ClientThread());
t.start();
}
});
}
class ClientThread implements Runnable {
@Override
public void run()
{
// We got this IP from servlet and stored temporarily, so retrieve it from there.
String socketServerIP = ((GlobalStore) RandomIDActivity.this.getApplication()).getSocketIPAddress();
Log.d("socketServerIP", socketServerIP);
try {
InetAddress serverAddr = InetAddress.getByName(socketServerIP);
socket = new Socket(serverAddr, SERVERPORT);
pw = new PrintWriter(socket.getOutputStream(), true);
EditText randTxtField = (EditText) findViewById(R.id.editText1);
pw.println(randTxtField.getText().toString());
//output.write(imgbyte,0,imgbyte.length);
pw.flush();
// Read randrom ID returned by Socket
BufferedReader socketReader;
try {
socketReader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
msgStr = socketReader.readLine();
Log.d("msgStr: ", msgStr);
if (msgStr.equalsIgnoreCase("SUCCESS") )
{
socket.close();
// Crashing if I call alert dialog like this.
CobrowseAlertDialog("Successfully connected! Click OK to starts screen sharing!", true);
//Intent intent = new Intent(context, MainActivity.class);
//startActivity(intent);
}
else
{
CobrowseAlertDialog("There seems to be problem in connecting..Try connecting it again with proper Random Auth ID!", false);
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
catch (UnknownHostException e1) {
e1.printStackTrace();
}
catch (IOException e1) {
e1.printStackTrace();
}
}
}
public void CobrowseAlertDialog(String msg, boolean bMove) {
AlertDialog.Builder builder = new AlertDialog.Builder(RandomIDActivity.this); // getParent()
builder.setTitle("Cobrowsing")
.setMessage(msg)
.setCancelable(false)
.setNegativeButton("Ok",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
dialog.cancel();
//Intent intent = new Intent(context, MainActivity.class);
//startActivity(intent);
}
});
AlertDialog alert = builder.create();
alert.show();
}
}
logcat的：
03-24 17:12:20.353: D/socketServerIP(32717): 192.168.1.21
03-24 17:12:20.503: D/msgStr:(32717): SUCCESS
03-24 17:12:29.952: W/dalvikvm(32717): threadid=17: thread exiting with uncaught exception (group=0x415efba8)
03-24 17:12:33.926: W/jdwp(32717): Debugger is telling the VM to exit with code=1
答案 0 :(得分：0)
后台线程无法弹出对话框。您可以做的是，您可以在UI线程上使用一些处理程序来弹出对话框外观。
其他一种替代方案也可用，但不太好，推荐不太好
runOnUiThread(new Runnable(){
public void run(){
////code for alert dialog
}
});
答案 1 :(得分：0)
在android中，Thread并不直接更新UI线程。如果你想更新你的UI，你应该使用
处理程序。
Handler mHandler;
@Override
public void run()
{
// We got this IP from servlet and stored temporarily, so retrieve it from there.
String socketServerIP = ((GlobalStore) RandomIDActivity.this.getApplication()).getSocketIPAddress();
Log.d("socketServerIP", socketServerIP);
try {
InetAddress serverAddr = InetAddress.getByName(socketServerIP);
socket = new Socket(serverAddr, SERVERPORT);
pw = new PrintWriter(socket.getOutputStream(), true);
EditText randTxtField = (EditText) findViewById(R.id.editText1);
pw.println(randTxtField.getText().toString());
//output.write(imgbyte,0,imgbyte.length);
pw.flush();
// Read randrom ID returned by Socket
BufferedReader socketReader;
try {
socketReader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
msgStr = socketReader.readLine();
Log.d("msgStr: ", msgStr);
//add handler here
mHandler.post(new Runnable{
public void run(){
if (msgStr.equalsIgnoreCase("SUCCESS") )
{
socket.close();
// Crashing if I call alert dialog like this.
CobrowseAlertDialog("Successfully connected! Click OK to starts screen sharing!", true);
//Intent intent = new Intent(context, MainActivity.class);
//startActivity(intent);
}
else
{
CobrowseAlertDialog("There seems to be problem in connecting..Try connecting it again with proper Random Auth ID!", false);
}
}
});
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
catch (UnknownHostException e1) {
e1.printStackTrace();
}
catch (IOException e1) {
e1.printStackTrace();
}
}
}
答案 2 :(得分：0)
在android中，Thread并不直接更新UI线程。如果你想更新你的UI，你应该使用
类ClientThread实现Runnable {
@Override
public void run()
{
// We got this IP from servlet and stored temporarily, so retrieve it from there.
String socketServerIP = ((GlobalStore) RandomIDActivity.this.getApplication()).getSocketIPAddress();
Log.d("socketServerIP", socketServerIP);
try {
InetAddress serverAddr = InetAddress.getByName(socketServerIP);
socket = new Socket(serverAddr, SERVERPORT);
pw = new PrintWriter(socket.getOutputStream(), true);
EditText randTxtField = (EditText) findViewById(R.id.editText1);
pw.println(randTxtField.getText().toString());
//output.write(imgbyte,0,imgbyte.length);
pw.flush();
// Read randrom ID returned by Socket
BufferedReader socketReader;
try {
socketReader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
msgStr = socketReader.readLine();
Log.d("msgStr: ", msgStr);
if (msgStr.equalsIgnoreCase("SUCCESS") )
{
socket.close();
// Crashing if I call alert dialog like this.
CobrowseAlertDialog("Successfully connected! Click OK to starts screen sharing!", true);
//Intent intent = new Intent(context, MainActivity.class);
//startActivity(intent);
}
else
{
CobrowseAlertDialog("There seems to be problem in connecting..Try connecting it again with proper Random Auth ID!", false);
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
catch (UnknownHostException e1) {
e1.printStackTrace();
}
catch (IOException e1) {
e1.printStackTrace();
}
}
}
Handler handler = new Handler（）;
按钮connectBtn =（按钮）findViewById（R.id.button2）; connectBtn.setOnClickListener（new View.OnClickListener（）{
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
handler.post(new Runnable {
@Override
public void run()
{
// We got this IP from servlet and stored temporarily, so retrieve it from there.
String socketServerIP = ((GlobalStore) RandomIDActivity.this.getApplication()).getSocketIPAddress();
Log.d("socketServerIP", socketServerIP);
try {
InetAddress serverAddr = InetAddress.getByName(socketServerIP);
socket = new Socket(serverAddr, SERVERPORT);
pw = new PrintWriter(socket.getOutputStream(), true);
EditText randTxtField = (EditText) findViewById(R.id.editText1);
pw.println(randTxtField.getText().toString());
//output.write(imgbyte,0,imgbyte.length);
pw.flush();
// Read randrom ID returned by Socket
BufferedReader socketReader;
try {
socketReader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
msgStr = socketReader.readLine();
Log.d("msgStr: ", msgStr);
if (msgStr.equalsIgnoreCase("SUCCESS") )
{
socket.close();
// Crashing if I call alert dialog like this.
CobrowseAlertDialog("Successfully connected! Click OK to starts screen sharing!", true);
//Intent intent = new Intent(context, MainActivity.class);
//startActivity(intent);
}
else
{
CobrowseAlertDialog("There seems to be problem in connecting..Try connecting it again with proper Random Auth ID!", false);
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
catch (UnknownHostException e1) {
e1.printStackTrace();
}
catch (IOException e1) {
e1.printStackTrace();
}
}
}
）; } }）;