Toast显示一个值但textview抛出Null指针错误

时间：2016-06-10 04:34:09

标签： php android nullpointerexception

我正在使用此代码将数据发布到php - 

   package com.nas.cruzer;

import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.ResponseHandler;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.BasicResponseHandler;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import com.nas.cruzer.UserEditProfileActivity.UpdateInfo;
import com.nas.cruzer.util.JSONParser;
import com.nas.cruzer.util.UserInfo;
import com.nas.cruzer.util.Util;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.os.AsyncTask;
import android.os.Bundle;
import android.os.Environment;
import android.os.StrictMode;
import android.util.Log;
import android.view.MenuItem;
import android.webkit.JavascriptInterface;
import android.webkit.WebView;
import android.widget.TextView;
import android.widget.Toast;

@SuppressLint("SetJavaScriptEnabled") public class payment extends Activity {

     private static final String TAG = "payment.java";
    private WebView webView;
    JSONParser jparser=new JSONParser();
    public static HashMap<String, String> pay;
    public static final String payUrl = "http://fuelongo.com/ap2/fog/pay/PayUMoney_form.php";
    String x,y,tot,fuel,mail,phone,responseServer;
    TextView test;
    Context con= payment.this;

    @SuppressLint("JavascriptInterface") public void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);
        new PostDataAsyncTask().execute();
        setContentView(R.layout.payment);
       webView = (WebView) findViewById(R.id.pay);
        webView.getSettings().setJavaScriptEnabled(true);
        webView.addJavascriptInterface(new WebAppInterface(this), "Android"); 


        webView.loadUrl(payUrl);

        //test=(TextView) findViewById(R.id.x);
    }


    public class PostDataAsyncTask extends AsyncTask<String, String, String> {

        protected void onPreExecute() {
            super.onPreExecute();
            // do stuff before posting data
        }

        @Override
        protected String doInBackground(String... strings) {
            try {

                    postText();


                // post a file


            } catch (NullPointerException e) {
                e.printStackTrace();
            } catch (Exception e) {
                e.printStackTrace();
            }
            return null;
        }

        @Override
        protected void onPostExecute(String lenghtOfFile) {
            // do stuff after posting data
        }
    }

    // this will post our text data
    private void postText(){
        try{
            // url where the data will be posted

            Log.v(TAG, "postURL: " + payUrl);

            // HttpClient
            HttpClient httpClient = new DefaultHttpClient();

            // post header
            HttpPost httpPost = new HttpPost(payUrl);

            // add your data
            List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(2);
            nameValuePairs.add(new BasicNameValuePair("firstname", "Mike"));
            nameValuePairs.add(new BasicNameValuePair("lastname", "Dalisay"));
            nameValuePairs.add(new BasicNameValuePair("email", "mike@testmail.com"));

            httpPost.setEntity(new UrlEncodedFormEntity(nameValuePairs));

            // execute HTTP post request
            HttpResponse response = httpClient.execute(httpPost);
            HttpEntity resEntity = response.getEntity();

            if (resEntity != null) {

                String responseStr = EntityUtils.toString(resEntity).trim();
                Log.v(TAG, "Response: " +  responseStr);

                // you can add an if statement here and do other actions based on the response
            }

        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }






    public class WebAppInterface {
        Context mContext;

        /** Instantiate the interface and set the context */
        WebAppInterface(Context c) {
            mContext = c;





        }







        /** Show a toast from the web page */

         }
        }

在我的php中执行查询后的上述代码获得了所需的值并且正在烘烤，但是当我尝试将文本设置为文本视图时，它显示Null Pointer异常。

任何帮助？

这是我的log cat out＆＃34; s＆＃34;是我发布的值，kitkat是从数据库中查询的值

   06-10 15:37:56.390: V/payment.java(28930): Response: Array
06-10 15:37:56.390: V/payment.java(28930): (
06-10 15:37:56.390: V/payment.java(28930):     [firstname] => Mike
06-10 15:37:56.390: V/payment.java(28930):     [lastname] => Dalisay
06-10 15:37:56.390: V/payment.java(28930):     [email] => mike@testmail.com
06-10 15:37:56.390: V/payment.java(28930): )
06-10 15:37:56.390: V/payment.java(28930): mike@testmail.com<html>
06-10 15:37:56.390: V/payment.java(28930):   <head>
06-10 15:37:56.390: V/payment.java(28930):   <script>
06-10 15:37:56.390: V/payment.java(28930):     var hash = '';
06-10 15:37:56.390: V/payment.java(28930):     function submitPayuForm() {
06-10 15:37:56.390: V/payment.java(28930):       if(hash == '') {
06-10 15:37:56.390: V/payment.java(28930):         return;
06-10 15:37:56.390: V/payment.java(28930):       }
06-10 15:37:56.390: V/payment.java(28930):       var payuForm = document.forms.payuForm;
06-10 15:37:56.390: V/payment.java(28930):       payuForm.submit();
06-10 15:37:56.390: V/payment.java(28930):     }
06-10 15:37:56.390: V/payment.java(28930):   </script>
06-10 15:37:56.390: V/payment.java(28930):   </head>
06-10 15:37:56.390: V/payment.java(28930):   <body onload="submitPayuForm()">
06-10 15:37:56.390: V/payment.java(28930):     <h2>PayU Form</h2>
06-10 15:37:56.390: V/payment.java(28930):     <br/>
06-10 15:37:56.390: V/payment.java(28930):      
06-10 15:37:56.390: V/payment.java(28930):       <span style="color:red">Please fill all mandatory fields.</span>
06-10 15:37:56.390: V/payment.java(28930):       <br/>
06-10 15:37:56.390: V/payment.java(28930):       <br/>
06-10 15:37:56.390: V/payment.java(28930):         <form action="" method="post" name="payuForm">
06-10 15:37:56.390: V/payment.java(28930):       <input type="hidden" name="key" value="JBZaLc" />
06-10 15:37:56.390: V/payment.java(28930):       <input type="hidden" name="hash" value=""/>
06-10 15:37:56.390: V/payment.java(28930):       <input type="hidden" name="txnid" value="61937a215af325da6a54" />
06-10 15:37:56.390: V/payment.java(28930):       <table>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td><b>Mandatory Parameters</b></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>Amount: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="amount" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>First Name: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="firstname" id="firstname" value="Mike" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>Email: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="email" id="email" value="mike@testmail.com" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>Phone: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="phone" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>Product Info: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td colspan="3"><textarea name="productinfo"></textarea></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>Success URI: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td colspan="3"><input name="surl" value="" size="64" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>Failure URI: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td colspan="3"><input name="furl" value="" size="64" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td colspan="3"><input type="hidden" name="service_provider" value="payu_paisa" size="64" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td><b>Optional Parameters</b></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>Last Name: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="lastname" id="lastname" value="Dalisay" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>Cancel URI: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="curl" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>Address1: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="address1" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>Address2: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="address2" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>City: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="city" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>State: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="state" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>Country: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="country" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>Zipcode: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="zipcode" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>UDF1: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="udf1" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>UDF2: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="udf2" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>UDF3: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="udf3" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>UDF4: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="udf4" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):           <td>UDF5: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="udf5" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):           <td>PG: </td>
06-10 15:37:56.390: V/payment.java(28930):           <td><input name="pg" value="" /></td>
06-10 15:37:56.390: V/payment.java(28930):         </tr>
06-10 15:37:56.390: V/payment.java(28930):         <tr>
06-10 15:37:56.390: V/payment.java(28930):                       <td colspan="4"><input type="submit" value="Submit" /></td>
06-10 15:37:56.390: V/payment.java(28930):                   </tr>
06-10 15:37:56.390: V/payment.java(28930):       </table>
06-10 15:37:56.390: V/payment.java(28930):     </form>
06-10 15:37:56.390: V/payment.java(28930):   </body>
06-10 15:37:56.390: V/payment.java(28930): </html>

4 个答案:

答案 0 :(得分：0)

使用AsynTask Class或Intent服务来处理UI更改。

答案 1 :(得分：0)

由于此处的reverseString，因此不会抛出空指针异常。这是因为测试为空。

这可能是由于以下任何原因造成的。 1.在调用test.setText之前，确保运行下面的代码 test =（TextView）findViewById（R.id.x）

  1. 确保查看＆＃39; x＆＃39;存在于你正在膨胀的布局中。

    2. 还要确保在主线程上更新textview。

答案 2 :(得分：0)

首先是取消评论test=(TextView) findViewById(R.id.x); 第二件事是在初始化textview之前调用new PostDataAsyncTask().execute()， 所以首先初始化所有变量，然后执行其余的代码加载，执行等。

你的onCreate（）代码应该是这样的

    super.onCreate(savedInstanceState);
    setContentView(R.layout.payment);
    test=(TextView) findViewById(R.id.x);
    webView = (WebView) findViewById(R.id.pay);
    webView.getSettings().setJavaScriptEnabled(true);
    webView.addJavascriptInterface(new WebAppInterface(this), "Android");
    webView.loadUrl(payUrl);
    new PostDataAsyncTask().execute();

然后test.setText("whatever you want"); 并检查id.x

中payment layout是否可用

答案 3 :(得分：0)

使用以下代码解决问题：

 public void postData() throws IOException, ClientProtocolException {  

        List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();  
        nameValuePairs.add(new BasicNameValuePair("name", x));  
        nameValuePairs.add(new BasicNameValuePair("mail", y));
        nameValuePairs.add(new BasicNameValuePair("phone", phone));
        nameValuePairs.add(new BasicNameValuePair("fuel", fuel));
        nameValuePairs.add(new BasicNameValuePair("total", tot));

        HttpClient httpclient = new DefaultHttpClient();  
        HttpPost httppost = new HttpPost(payUrl);  
        httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));  

        HttpResponse response = httpclient.execute(httppost);  
        String data = new BasicResponseHandler().handleResponse(response);
       Log.e("data",data);

        webView.loadData(data, "text/html", "utf-8");
   }

但是webview中的按钮无效 有人可以解释一下这段代码的作用。

相关问题
最新问题