当我使用我的Android手机将json发送到服务器并且应用程序被刷新时。但是当我使用模拟器时它会起作用。
Application has stopped unexpectedly!
代码：
String url = <<the url>>;
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("email", email));
params.add(new BasicNameValuePair("password", password));
try {
httpPost.setEntity(new UrlEncodedFormEntity(params));
httpPost.getParams().setParameter(CoreProtocolPNames.USE_EXPECT_CONTINUE, Boolean.FALSE);
} catch (UnsupportedEncodingException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
HttpResponse httpResponse = null;
StringBuilder builder = new StringBuilder();
JSONTokener tokener = null;
try {
httpResponse = httpClient.execute(httpPost);
HttpEntity entity = httpResponse.getEntity();
InputStream content = entity.getContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(content));
String line;
while((line = reader.readLine()) != null){
builder.append(line);
}
tokener = new JSONTokener(builder.toString());
String execution = null;
try{
//convert the api response into json object
JSONObject jsonObject = new JSONObject(tokener);
execution = jsonObject.get("execution").toString();
//display the json object
} catch(Exception e){
e.printStackTrace();
}
if (execution.equals("true")){
//run method to open message dialog
openSuccessDialog(v, "You have logged in your account.");
}
else{
//run method to open message dialog
openErrorDialog(v, "Execution false. Your email and password doesn't match.");
}
logcat的：
08-01 10:26:52.985: W/dalvikvm(4335): threadid=1: thread exiting with uncaught exception (group=0x416a7e18)
08-01 10:26:52.995: E/AndroidRuntime(4335): FATAL EXCEPTION: main
08-01 10:26:52.995: E/AndroidRuntime(4335): Process: com.entityaccess.assetmappingsprintone, PID: 4335
08-01 10:26:52.995: E/AndroidRuntime(4335): android.os.NetworkOnMainThreadException
08-01 10:26:52.995: E/AndroidRuntime(4335): at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1239)
08-01 10:26:52.995: E/AndroidRuntime(4335): at libcore.io.BlockGuardOs.connect(BlockGuardOs.java:84)
08-01 10:26:52.995: E/AndroidRuntime(4335): at libcore.io.IoBridge.connectErrno(IoBridge.java:127)
08-01 10:26:52.995: E/AndroidRuntime(4335): at libcore.io.IoBridge.connect(IoBridge.java:112)
08-01 10:26:52.995: E/AndroidRuntime(4335): at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:192)
08-01 10:26:52.995: E/AndroidRuntime(4335): at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:459)
08-01 10:26:52.995: E/AndroidRuntime(4335): at java.net.Socket.connect(Socket.java:873)
08-01 10:26:52.995: E/AndroidRuntime(4335): at org.apache.http.conn.scheme.PlainSocketFactory.connectSocket(PlainSocketFactory.java:125)
08-01 10:26:52.995: E/AndroidRuntime(4335): at org.apache.http.impl.conn.DefaultClientConnectionOperator.openConnection(DefaultClientConnectionOperator.java:144)
08-01 10:26:52.995: E/AndroidRuntime(4335): at org.apache.http.impl.conn.AbstractPoolEntry.open(AbstractPoolEntry.java:164)
08-01 10:26:52.995: E/AndroidRuntime(4335): at org.apache.http.impl.conn.AbstractPooledConnAdapter.open(AbstractPooledConnAdapter.java:119)
08-01 10:26:52.995: E/AndroidRuntime(4335): at org.apache.http.impl.client.DefaultRequestDirector.execute(DefaultRequestDirector.java:367)
08-01 10:26:52.995: E/AndroidRuntime(4335): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:754)
08-01 10:26:52.995: E/AndroidRuntime(4335): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:519)
08-01 10:26:52.995: E/AndroidRuntime(4335): at org.apache.http.impl.client.AbstractHttpClient.execute(AbstractHttpClient.java:497)
08-01 10:26:52.995: E/AndroidRuntime(4335): at com.entityaccess.assetmappingsprintone.LoginActivity$1.onClick(LoginActivity.java:119)
08-01 10:26:52.995: E/AndroidRuntime(4335): at android.view.View.performClick(View.java:4480)
08-01 10:26:52.995: E/AndroidRuntime(4335): at android.view.View$PerformClick.run(View.java:18686)
08-01 10:26:52.995: E/AndroidRuntime(4335): at android.os.Handler.handleCallback(Handler.java:733)
08-01 10:26:52.995: E/AndroidRuntime(4335): at android.os.Handler.dispatchMessage(Handler.java:95)
08-01 10:26:52.995: E/AndroidRuntime(4335): at android.os.Looper.loop(Looper.java:157)
08-01 10:26:52.995: E/AndroidRuntime(4335): at android.app.ActivityThread.main(ActivityThread.java:5872)
08-01 10:26:52.995: E/AndroidRuntime(4335): at java.lang.reflect.Method.invokeNative(Native Method)
08-01 10:26:52.995: E/AndroidRuntime(4335): at java.lang.reflect.Method.invoke(Method.java:515)
08-01 10:26:52.995: E/AndroidRuntime(4335): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:858)
08-01 10:26:52.995: E/AndroidRuntime(4335): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:674)
08-01 10:26:52.995: E/AndroidRuntime(4335): at dalvik.system.NativeStart.main(Native Method)
08-01 10:26:55.858: D/Process(4335): killProcess, pid=4335
08-01 10:26:55.858: D/Process(4335): com.android.internal.os.RuntimeInit$UncaughtHandler.uncaughtException:131 java.lang.ThreadGroup.uncaughtException:693 java.lang.ThreadGroup.uncaughtException:690
如何解决这个问题，让我的手机能够将json发送到服务器？
答案 0 :(得分：0)
您无法在主线程上进行网络调用。您需要在单独的线程中运行此代码，您的问题将得到解决。
例外很明确！
08-01 10:26:52.995: E/AndroidRuntime(4335): android.os.NetworkOnMainThreadException
您可以在Android上选择多种选择。您可以使用java中熟知的Thread类。或者您可以使用AsyncTask。如果你愿意，你也可以把它扔进IntentService。选项在那里，您可以根据自己的需要选择最佳选择。
答案 1 :(得分：0)
首先，这个问题已被多次询问过...在提问之前你应该做一些搜索：）
错误基本上意味着您正在UI线程上运行http请求，这是您不应该做的事情。你要做的是将请求放在Asynctask中，如下所示：
class postRequest extends AsyncTask<String, Void, String> {
@Override
protected String doInBackground(String... params) {
String url = <<the url>>;
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("email", email));
params.add(new BasicNameValuePair("password", password));
try {
httpPost.setEntity(new UrlEncodedFormEntity(params));
httpPost.getParams().setParameter(CoreProtocolPNames.USE_EXPECT_CONTINUE, Boolean.FALSE);
} catch (UnsupportedEncodingException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
HttpResponse httpResponse = null;
StringBuilder builder = new StringBuilder();
JSONTokener tokener = null;
try {
httpResponse = httpClient.execute(httpPost);
HttpEntity entity = httpResponse.getEntity();
InputStream content = entity.getContent();
BufferedReader reader = new BufferedReader(new InputStreamReader(content));
String line;
while((line = reader.readLine()) != null){
builder.append(line);
}
tokener = new JSONTokener(builder.toString());
String execution = null;
try{
//convert the api response into json object
JSONObject jsonObject = new JSONObject(tokener);
execution = jsonObject.get("execution").toString();
//display the json object
} catch(Exception e){
e.printStackTrace();
}
if (execution.equals("true")){
//run method to open message dialog
openSuccessDialog(v, "You have logged in your account.");
}
else{
//run method to open message dialog
openErrorDialog(v, "Execution false. Your email and password doesn't match.");
}
}
答案 2 :(得分：0)
创建一个AsyncTask并将您的代码放在doInBackground中。
private class YourTask extends AsyncTask<String, String, String> {
protected Long doInBackground(String... params) {
// your network call here
}
protected void onPostExecute(String result) {
// open your dialogs here
}
}
然后调用execute来运行你的任务：
new YourTask().execute();
说明：在Android中，所有网络访问（以及任何其他阻止代码）都需要在main thread之外完成，以便UI不会阻止。 AsyncTask是一种方便的方法。它在一个新线程中运行doInBackground，当它完成后，它在主线程中运行onPostExecute，因此你可以在UI中显示结果。