我正在尝试根据 ListView 中按下的项目来显示信息。我正在使用 HTTP GET 请求来获取信息。
当您单击 ListView 中的某个项目(配置文件)时,应用程序会获取该配置文件名称,并根据该名称在下一个 Activity 中显示该配置文件的信息,但这不起作用,我不断收到 JSONException
错误。我不知道是什么原因造成的,或者如果我实现这一目标的方法是错误的,任何帮助都会很棒。谢谢。
在这里,我将配置文件的名称发送到下一个 Activity (此类有更多代码,但与此问题无关):
公共(public)类 EditProfiles 扩展 BaseListActivity 实现 GetProfilesListener{
TextView errorMessage;
String email;
private static final String TAG_PNAME = "profilename";
/**
* Called when activity is first created.
*/
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_edit_profiles);
ListView list = getListView();
list.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// getting values from selected ListItem
String profilename = ((TextView) view.findViewById(R.id.editProfiles_profile_name)).getText()
.toString();
Intent in = new Intent(getApplicationContext(), EditSingleProfile.class);
// sending profilename to next activity
in.putExtra(TAG_PNAME, profilename);
// Starts activity
startActivity(in);
}
});
}
这是我想要从个人资料中获取详细信息的 Activity :
public class EditSingleProfile extends BaseViewEditProfile{
Spinner inputType;
EditText inputName;
EditText inputAge;
EditText inputBreed;
EditText inputAbout;
ImageView selectPicture;
Button change;
TextView message;
//Json node names.
private static final String TAG_SUCCESS = "success";
private static final String TAG_PROFILE = "profile";
private static final String TAG_PNAME = "profilename";
private static final String TAG_PAGE = "petage";
private static final String TAG_BREED = "petbreed";
private static final String TAG_ABOUT = "profileabout";
//JSON parser class
JSONParser jsonParser = new JSONParser();
// single profile url
private static final String url_profile_details = "http://gatoandroidapp.comeze.com/profile_details.php";
//Create field SELECT_PICTURE to be used in the class.
private static final int SELECT_PICTURE = 1;
private String selectedImagePath;
String pimage;
String profilename;
/**
* Called when activity is created.
*/
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_edit_profile_view);
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
// getting profile details from intent
Intent i = getIntent();
// getting profile name from intent
profilename = i.getStringExtra(TAG_PNAME);
// Sets view title.
this.setTitle(profilename);
// Get profile's details in Background Thread
new GetProfiles().execute();
/**
* Background AsyncTask to Get profile details.
*/
class GetProfiles extends AsyncTask<String, String, String> {
// Progress Dialog
private ProgressDialog pDialog;
/**
* Before starting background thread Show Progress Dialog
*/
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(EditSingleProfile.this);
pDialog.setMessage("Loading profile details...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(true);
pDialog.show();
}
/**
* Getting profile details in background thread
*/
protected String doInBackground(String... params) {
// updating UI from Background Thread
runOnUiThread(new Runnable() {
public void run() {
// Check for success tag
int success;
try {
// Building Parameters
List<NameValuePair> params = new ArrayList<NameValuePair>();
params.add(new BasicNameValuePair("profilename", profilename));
// getting profile details by making HTTP request
JSONObject json = jsonParser.makeHttpRequest(
url_profile_details, "GET", params);
// check your log for json response
Log.d("Single Profile Details", json.toString());
// json success tag
success = json.getInt(TAG_SUCCESS);
if (success == 1) {
// successfully received product details
JSONArray profileObj = json
.getJSONArray(TAG_PROFILE); // JSON Array
// get first profile object from JSON Array
JSONObject profile = profileObj.getJSONObject(0);
inputName = (EditText) findViewById(R.id.editProfile_profileName_editText);
inputAge = (EditText) findViewById(R.id.editProfile_age_editText);
inputBreed = (EditText) findViewById(R.id.editProfile_breed_editText);
inputAbout = (EditText) findViewById(R.id.editProfile_about_editText);
// display product data in EditText
inputName.setText(profile.getString(TAG_PNAME));
inputAge.setText(profile.getString(TAG_PAGE));
inputBreed.setText(profile.getString(TAG_BREED));
inputAbout.setText(profile.getString(TAG_ABOUT));
}else{
// profile with name not found
}
} catch (JSONException e) {
e.printStackTrace();
}
}
});
return null;
}
/**
* After completing background task Dismiss the progress dialog.
*/
protected void onPostExecute(String file_url) {
// dismiss the dialog once got all details
pDialog.dismiss();
}
}
这是我的 JSON 解析器:
public class JSONParser {
static InputStream is = null;
static JSONObject jObj = null;
static String json = "";
// constructor
public JSONParser() {
}
// function get json from url
// by making HTTP POST or GET mehtod
public JSONObject makeHttpRequest(String url, String method,
List<NameValuePair> params) {
// Making HTTP request
try {
// check for request method
if(method.equalsIgnoreCase("POST")){
// request method is POST
// defaultHttpClient
DefaultHttpClient httpClient = new DefaultHttpClient();
HttpPost httpPost = new HttpPost(url);
httpPost.setEntity(new UrlEncodedFormEntity(params));
HttpResponse httpResponse = httpClient.execute(httpPost);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}else if(method.equalsIgnoreCase("GET")){
// request method is GET
DefaultHttpClient httpClient = new DefaultHttpClient();
String paramString = URLEncodedUtils.format(params, "utf-8");
url += "?" + paramString;
HttpGet httpGet = new HttpGet(url);
HttpResponse httpResponse = httpClient.execute(httpGet);
HttpEntity httpEntity = httpResponse.getEntity();
is = httpEntity.getContent();
}
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
} catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(
is, "iso-8859-1"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
is.close();
json = sb.toString();
} catch (Exception e) {
Log.e("Buffer Error", "Error converting result " + e.toString());
}
// try parse the string to a JSON object
try {
jObj = new JSONObject(json);
} catch (JSONException e) {
Log.e("JSON Parser", "Error parsing data " + e.toString());
}
// return JSON String
return jObj;
}
}
这是我的 PHP 代码:
<?php
/*
* Gets single profile details
* A profile is identified by profile name (pname)
*/
// array for JSON response
$response = array();
// include db connect class
require_once __DIR__ . '/DB_Connect.php';
// connecting to db
$db = new DB_CONNECT();
// check for post data
if (isset($_GET["profilename"])) {
$profilename = $_GET['profilename'];
// get a profile from profiles table
$result = mysql_query("SELECT * FROM profiles WHERE profilename = $profilename");
if (!empty($result)) {
// check for empty result
if (mysql_num_rows($result) > 0) {
$result = mysql_fetch_array($result);
$profile = array();
$profile["profilename"] = $result["profilename"];
$profile["petage"] = $result["petage"];
$profile["petbreed"] = $result["petbreed"];
$profile["profileabout"] = $result["profileabout"];
// success
$response["success"] = 1;
// user node
$response["profile"] = array();
array_push($response["profile"], $profile);
// echoing JSON response
echo json_encode($response);
} else {
// no profile found
$response["success"] = 0;
$response["message"] = "No profile found";
// echo no users JSON
echo json_encode($response);
}
} else {
// no profile found
$response["success"] = 0;
$response["message"] = "No profile found";
// echo no users JSON
echo json_encode($response);
}
} else {
// required field is missing
$response["success"] = 0;
$response["message"] = "Required field(s) is missing";
// echoing JSON response
echo json_encode($response);
}
?>
这是错误日志:
04-07 16:22:00.156: E/JSON Parser(15588): Error parsing data org.json.JSONException: Value <br><table of type java.lang.String cannot be converted to JSONObject
04-07 16:22:00.156: D/AndroidRuntime(15588): Shutting down VM
04-07 16:22:00.156: W/dalvikvm(15588): threadid=1: thread exiting with uncaught exception (group=0x4123f908)
04-07 16:22:00.159: E/AndroidRuntime(15588): FATAL EXCEPTION: main
04-07 16:22:00.159: E/AndroidRuntime(15588): java.lang.NullPointerException
04-07 16:22:00.159: E/AndroidRuntime(15588): at com.gmail.lucsantisf.software_project.views.EditSingleProfile$GetProfiles$1.run(EditSingleProfile.java:249)
04-07 16:22:00.159: E/AndroidRuntime(15588): at android.os.Handler.handleCallback(Handler.java:615)
04-07 16:22:00.159: E/AndroidRuntime(15588): at android.os.Handler.dispatchMessage(Handler.java:92)
04-07 16:22:00.159: E/AndroidRuntime(15588): at android.os.Looper.loop(Looper.java:153)
04-07 16:22:00.159: E/AndroidRuntime(15588): at android.app.ActivityThread.main(ActivityThread.java:5006)
04-07 16:22:00.159: E/AndroidRuntime(15588): at java.lang.reflect.Method.invokeNative(Native Method)
04-07 16:22:00.159: E/AndroidRuntime(15588): at java.lang.reflect.Method.invoke(Method.java:511)
04-07 16:22:00.159: E/AndroidRuntime(15588): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:821)
04-07 16:22:00.159: E/AndroidRuntime(15588): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:584)
04-07 16:22:00.159: E/AndroidRuntime(15588): at dalvik.system.NativeStart.main(Native Method)
感谢您的帮助。
好吧,我修复了错误,问题与 PHP 文件中的连接和这一行有关: require_once DIR 。 '/DB_Connect.php';。
我使用了 Log.d("JSON Parser", json );在 eclipse 中读取 logcat 中的 PHP 错误,它一直告诉我无法打开流:没有这样的文件或目录并且打开失败需要,所以我将所需的文件放在与我的 php 文件相同的目录中以及 php 文件中,然后我替换了这一行:require_once _DIR_。 '/DB_Connect.php'; 如下:require_once 'DB_Connect.php';
如果有人尝试做类似的事情,Java 代码是完美的。
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