Question

我正在从我的应用程序向服务器发送一些信息并等待响应。在我发送之前，我将我的textview设置为消息以显示“处理请求”，并在收到响应后显示不同的消息。

未显示此处理消息。是否因为其他操作导致UI被阻止。怎么处理这个。由于需要显示响应，线程无法给出正确的结果。因此涉及线程中的UI。

 package com.PandG.app.android.activities;

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;

import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.params.HttpConnectionParams;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.content.Intent;
import android.os.Bundle;
import android.text.Html;
import android.util.Log;
import android.view.View;
import android.view.Window;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

import com.PandG.app.android.R;
import com.PandG.app.android.dataAccess.SettingsDBAccess;
import com.PandG.app.android.entity.Job;
import com.PandG.app.android.entity.Settings;
import com.PandG.app.android.services.JobsManager;
import com.lib.android.Utils.Utils;
import com.lib.android.activity.BaseActivity;
import com.lib.android.dataAccess.DatabaseManager;

public class JobCheckoutActivity extends BaseActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setViewContent();
    }

    private void setViewContent() {

        Settings setting = getSettings();
        requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);
        setContentView(R.layout.job_checkout);
        getWindow().setFeatureInt(Window.FEATURE_CUSTOM_TITLE, R.layout.customtitle);
        //new DataProcess().execute(null);
        TextView text1 = (TextView)findViewById(R.id.checkoutmessage);
        text1.setText("Processiong Job Cart ...");
        if(setting!=null){
            TextView text2 = (TextView)findViewById(R.id.checkoutheading);
            text2.setVisibility(View.GONE);
            Button homeButton = (Button)findViewById(R.id.gohome);
            homeButton.setVisibility(View.GONE);
        JSONObject jobObject =encodeData(setting);
        sendDataToServer(jobObject);
        } 

    }
    private void sendDataToServer(JSONObject jobObject) {
        TextView text1 = (TextView)findViewById(R.id.checkoutmessage);
        text1.setText("Processiong Job Cart ...");
        HttpClient client = new DefaultHttpClient();
        HttpConnectionParams.setConnectionTimeout(client.getParams(), 10000); // Timeout
                                                                                // Limit
        HttpResponse response;
        try {
            HttpPost post = new HttpPost(Utils.getPostUrl());
            List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);
            nameValuePairs.add(new BasicNameValuePair("orderparameters",
                    jobObject.toString()));
            Log.i("Job ORDER", jobObject.toString());
            post.setEntity(new UrlEncodedFormEntity(nameValuePairs));

            response = client.execute(post);
            checkResponseFromServer(response);
            ClearCart();
        } catch (Exception e) {
            Log.w("error", "connection failed");
            Toast.makeText(this, "Order not placed due to connection error",
                    Toast.LENGTH_LONG);
            e.printStackTrace();

        }

    }

    private void ClearCart() {
        JobsManager.JobsCartList.clear();

    }

    private void checkResponseFromServer(HttpResponse response) {
        try {
            if (response != null) {
                InputStream in = response.getEntity().getContent();
                BufferedReader reader = new BufferedReader(
                        new InputStreamReader(in));

                String line;
                StringBuffer buffer = new StringBuffer();

                while ((line = reader.readLine()) != null) {
                    buffer.append(line);

                }

                in.close();

                JSONObject jsonResponse = new JSONObject(buffer.toString());
                Log.i("Status", jsonResponse.getString("status"));
                Log.i("Status", jsonResponse.getString("message"));
                Log.i("Status", jsonResponse.getString("debug"));
                TextView text1 = (TextView)findViewById(R.id.checkoutheading);
                text1.setVisibility(View.VISIBLE);
                TextView text = (TextView) findViewById(R.id.checkoutmessage);
                if (jsonResponse.getString("status").equals("SUCC")) {
                    text.setText( Html.fromHtml(getString(R.string.checkout_body1)));
                } else
                    text.setText(jsonResponse.getString("message")
                            + jsonResponse.getString("debug")); 

            }
        } catch (Exception ex) {

        }
    }


    private JSONObject encodeData(Settings setting) {
        JSONObject jobObject = new JSONObject();
        try {
            JSONObject jobject = new JSONObject();
            jobject.put("name", setting.getName());
            jobject.put("email", setting.getEmail());
            jobject.put("phone", setting.getPhone());
            jobject.put("school", setting.getSchool());
            jobject.put("major", setting.getMajor());

            jobObject.put("customer", jobject);
            JSONArray jobsarray = new JSONArray();
            for (Job job : JobsManager.JobsCartList) {
                JSONObject jobEntry = new JSONObject();
                jobEntry.put("jobtitle",job.getTitle());
                jobEntry.put("qty","1");
                jobsarray.put(jobEntry);
            }
            jobObject.put("orders", jobsarray);
        } catch (JSONException ex) {

        }
        return jobObject;
    }


    private Settings getSettings() {
        SettingsDBAccess settingsDBAccess = new SettingsDBAccess(
                DatabaseManager.getInstance());

        Settings setting = settingsDBAccess.getSetting();
        if (setting==null){
                startActivityForResult((new Intent(this,SettingsActivity.class)),Utils
                        .getDefaultRequestCode());
        }
        return setting;
    }
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {

        super.onActivityResult(requestCode, resultCode, data);
        Settings setting = new SettingsDBAccess(
                DatabaseManager.getInstance()).getSetting();
        if(setting!=null){
            JSONObject jobObject = encodeData(setting);
            sendDataToServer(jobObject);
        }

    }
/*  private class DataProcess extends AsyncTask {
        @Override
        protected void onPostExecute(Object result) {

        }

        @Override
        protected Object doInBackground(Object... arg0) {
            processDataandsend();
            return null;
        }

        private void processDataandsend() {
            Settings setting = getSettings();

            if(setting!=null){
                TextView text2 = (TextView)findViewById(R.id.checkoutheading);
                text2.setVisibility(View.GONE);
                Button homeButton = (Button)findViewById(R.id.gohome);
                homeButton.setVisibility(View.GONE);
            JSONObject jobObject =encodeData(setting);
            sendDataToServer(jobObject);

        }
    }

    } */
}

Answer 1

您不应该在UI线程上执行HTTP工作。而是使用AsyncTask

在AsyncTask中，您只能在两个位置更新UI：

  @Override
protected void onPreExecute() 
TextView.setText("Beginning HTTP-work..Please wait");
{

和

@Override
protected void onPostExecute(Void v) {
TextView.setText("Done..SUCCESS!");
}

使用这两个来在HTTP工作完成之前和之后更新UI。

Answer 2

长时间操作必须在后台进行。在Android上实现此功能的最佳方式是使用AsyncTask，以获取更多信息：http://developer.android.com/reference/android/os/AsyncTask.html

android文本不可见

2 个答案: