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How can I fix 'android.os.NetworkOnMainThreadException'?（66个答案）
9年前关闭了。
我在Web上成功部署了我的Web服务。我可以从我的应用程序中的Android 2.3调用它。但它无法从我的应用程序中调用Web服务，这是在Android 4.0上运行，它给出了空错误。我使用的最低SDK到API 10
我调用Web服务的代码如下

SoapObject request = new SoapObject(NAMESPACE, METHOD_NAME);
                request.addProperty("number", username.getText().toString());
                request.addProperty("password", password.getText().toString());
                SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(
                        SoapEnvelope.VER11);
                envelope.setOutputSoapObject(request);
                envelope.dotNet = true;
                try {
                    Toast.makeText(getBaseContext(), "Wait while connecting server",Toast.LENGTH_LONG).show();
                    HttpTransportSE androidHttpTransport = new HttpTransportSE(
                            URL);
                    androidHttpTransport.call(SOAP_ACTION, envelope);
                    SoapObject result = (SoapObject) envelope.bodyIn;
                    txt.setText("upto result");
                    if (result != null) {
                        String h = String.valueOf(result.getProperty(0));
                        txt.setText(h);
                        if (h.equalsIgnoreCase("true")) {
                            Intent myIntent = new Intent(getBaseContext(),
                                    ContactList.class);
                            myIntent.putExtra("mobileNumber", username
                                    .getText().toString());
                            startActivity(myIntent);
                        } else {
                            Toast.makeText(getBaseContext(), "Not register or invalid password",Toast.LENGTH_LONG).show();
                            txt.setText("Invalid Credential");
                        }
                    } else {
                        txt.setText("Error while connecting server");
                    }
                } catch (Exception e) {
                    e.printStackTrace();
                    txt.setText("Check internet connection" + e.getMessage());

                }

You Can Download my app from here
我的代码中有什么错误。
先谢了