我使用 php API从 mysql 获取数据，我使用Json_encode将结果传递给android但是当我将结果填充到android listview时，我只得到一个第一行。
这是我在网上的重新发布：
{"error":false,"user":{"paid_amount":"500","parking_duration":"59min","parking_name":"asass"}}
{"error":false,"user":{"paid_amount":"100","parking_duration":"22min","parking_name":"SDSDASDAS"}}
PHP部分：
...........
$usersArr = $db->getDriverHistory($plate_no);
if ($usersArr != false) {
foreach($usersArr as $key=>$user){
// use is found
$response[$key]["error"] = FALSE;
$response[$key]["user"]["paid_amount"] = $user["paid_amount"];
$response[$key]["user"]["parking_duration"] =
$user["parking_duration"];
$response[$key]["user"]["parking_name"] = $user["parking_name"];
$response = $response[$key] ;
// echo json_encode($response), "<br>";
// echo $response;
$json = json_encode($response);
echo $json,"<br>";
......
Android代码：我需要的是获得所有结果，其中牌号等于某个数字，但我只获得一行而不是所有行。
private void GetParkingInfo(final String plate_no) {
// Tag used to cancel the request
String tag_string_req = "req_Verfication";
progressBarList.setVisibility(View.VISIBLE);
// myList.setVisibility(View.GONE);
StringRequest strReq = new StringRequest(Request.Method.POST,
Urls.URL_driver_parking_information, new
Response.Listener<String>() {
@Override
public void onResponse(String response) {
Log.d(TAG, "cerfication Response: " + response.toString());
// Parsing json
for (int i = 0; i < response.length(); i++) {
try {
JSONObject jObj = new JSONObject(response);
boolean error = jObj.getBoolean("error");
// Check for error node in json
if (!error) {
// user successfully exist in database
JSONObject user = jObj.getJSONObject("user");
String paid_amount = user.getString("paid_amount");
String parking_duration =
user.getString("parking_duration");
String parking_name = user.getString("parking_name");
HashMap<String, String> prodHashMap = new
HashMap<String, String>();
prodHashMap.put("paid_amount", paid_amount);
prodHashMap.put("parking_duration", parking_duration);
prodHashMap.put("parking_name", parking_name);
ArrayList<HashMap<String, String>> wordList;
wordList = new ArrayList<HashMap<String, String>>();
wordList.add(prodHashMap);
userList = wordList ;
ShowListData();
progressBarList.setVisibility(View.GONE);
}
else{
// Error in login. Get the error message
// // hiding the progress bar
progressBarList.setVisibility(View.GONE);
myList.setVisibility(View.VISIBLE);
String errorMsg = jObj.getString("error_msg");
Toast.makeText(getApplicationContext(), errorMsg,
Toast.LENGTH_LONG).show();
}
} catch (JSONException e) {
// JSON error
e.printStackTrace();
Toast.makeText(getApplicationContext(), "Json error: " +
e.getMessage(), Toast.LENGTH_LONG).show();
// // hiding the progress bar
progressBarList.setVisibility(View.GONE);
myList.setVisibility(View.VISIBLE);
}
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.e(TAG, "Verfication error Error: " + error.getMessage());
Toast.makeText(getApplicationContext(),
"response error", Toast.LENGTH_LONG).show();
// Toast.makeText(getApplicationContext(),
// error.getMessage(), Toast.LENGTH_LONG).show();
// hiding the progress bar
progressBarList.setVisibility(View.GONE);
myList.setVisibility(View.VISIBLE);
}
}) {
@Override
protected Map<String, String> getParams() {
// Posting parameters to verfication url
Map<String, String> params = new HashMap<String, String>();
params.put("plate_no", plate_no);
return params;
}
};
// // Adding request to request queue
AppController.getInstance().addToRequestQueue(strReq,tag_string_req);
}
答案 0 :(得分：0)
您不会只获得一行，您每次迭代都会创建一个新的ArrayList。你只会以这种方式获得最后一排。
ArrayList<HashMap<String, String>> wordList;
wordList = new ArrayList<HashMap<String, String>>();
您需要在for循环之外初始化列表。
ArrayList<HashMap<String, String>> wordList = new ArrayList<HashMap<String, String>>();
for (int i = 0; i < response.length; i++) {
// add your information here
}
编辑::
我知道发生了什么。你正在循环String的长度。您需要将String响应转换为JSONArray并循环遍历。这样您就可以遍历数组中的每个JSONObject
List<HashMap<String, String>> wordList = new
ArrayList<HashMap<String,String>>();
try {
JSONArray array = new JSONArray(response);
for (int i = 0; i < array.length(); i++) {
JSONObject jsonObject = array.getJSONObject(i);
// get user // do rest of work
}
} catch (JSONException e) {
e.printStackTrace();
}
编辑2 ::
这应该让你去。我还没有经过测试，所以要小心任何缺失的括号。
private void GetParkingInfo(final String plate_no) {
// Tag used to cancel the request
String tag_string_req = "req_Verfication";
progressBarList.setVisibility(View.VISIBLE);
// myList.setVisibility(View.GONE);
StringRequest strReq = new StringRequest(Request.Method.POST,
Urls.URL_driver_parking_information, new
Response.Listener<String>() {
@Override
public void onResponse(String response) {
Log.d(TAG, "cerfication Response: " + response.toString());
try {
JSONArray jsonArray = new JSONArray(response);
if (jsonArray != null && !jsonArray.length() > 0) {
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject jsonObject = jsonArray.getJSONObject(i);
if (!jsonObject.isNull("user")) {
JSONObject user = jsonObject.getJSONObject("user");
String paid_amount = user.getString("paid_amount");
String parking_duration =
user.getString("parking_duration");
String parking_name = user.getString("parking_name");
HashMap<String, String> prodHashMap = new
HashMap<String, String>();
prodHashMap.put("paid_amount", paid_amount);
prodHashMap.put("parking_duration", parking_duration);
prodHashMap.put("parking_name", parking_name);
ArrayList<HashMap<String, String>> wordList;
wordList = new ArrayList<HashMap<String, String>>();
wordList.add(prodHashMap);
userList = wordList ;
ShowListData();
progressBarList.setVisibility(View.GONE);
}
}
}
} catch (JSONException e) {
e.printStackTrace();
Toast.makeText(getApplicationContext(), "Json error: " +
e.getMessage(), Toast.LENGTH_LONG).show();
// // hiding the progress bar
progressBarList.setVisibility(View.GONE);
myList.setVisibility(View.VISIBLE);
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.e(TAG, "Verfication error Error: " + error.getMessage());
Toast.makeText(getApplicationContext(),
"response error", Toast.LENGTH_LONG).show();
// Toast.makeText(getApplicationContext(),
// error.getMessage(), Toast.LENGTH_LONG).show();
// hiding the progress bar
progressBarList.setVisibility(View.GONE);
myList.setVisibility(View.VISIBLE);
}
}) {
@Override
protected Map<String, String> getParams() {
// Posting parameters to verfication url
Map<String, String> params = new HashMap<String, String>();
params.put("plate_no", plate_no);
return params;
}
};
// // Adding request to request queue
AppController.getInstance().addToRequestQueue(strReq,tag_string_req);
}
编辑3 ::
if ($usersArr != false) {
foreach($usersArr as $user){
$subresponse["error"] = FALSE;
$subresponse["user"]["paid_amount"] = $user["paid_amount"];
$subresponse["user"]["parking_duration"] = $user["parking_duration"];
$subresponse["user"]["parking_name"] = $user["parking_name"];
$response[] = $subresponse;
$json = json_encode($response);
我认为应该看起来
if ($usersArr != false) {
foreach($usersArr as $user){
$subresponse["error"] = FALSE;
$subresponse["user"]["paid_amount"] = $user["paid_amount"];
$subresponse["user"]["parking_duration"] = $user["parking_duration"];
$subresponse["user"]["parking_name"] = $user["parking_name"];
$response[] = $subresponse;
}
$json = json_encode($response);
答案 1 :(得分：0)
您已在错误的位置初始化了集合，请查看以下代码，这可能会对您有所帮助
ArrayList<HashMap<String, String>> wordList;
wordList = new ArrayList<HashMap<String, String>>();
for (int i = 0; i < response.length(); i++) {
try {
JSONObject jObj = new JSONObject(response);
boolean error = jObj.getBoolean("error");
// Check for error node in json
if (!error) {
// user successfully exist in database
JSONObject user = jObj.getJSONObject("user");
String paid_amount = user.getString("paid_amount");
String parking_duration =
user.getString("parking_duration");
String parking_name = user.getString("parking_name");
HashMap<String, String> prodHashMap = new
HashMap<String, String>();
prodHashMap.put("paid_amount", paid_amount);
prodHashMap.put("parking_duration", parking_duration);
prodHashMap.put("parking_name", parking_name);
wordList.add(prodHashMap);
;
progressBarList.setVisibility(View.GONE);
}
userList = wordList ;
ShowListData()
答案 2 :(得分：0)
此解决方案将帮助任何需要使用where子句基于android输入和volley库从mysql获取数据的人。
处理php函数的DBHandler：
.....
public function getDriverHistory($plate_no) {
$stmt = $this->conn->prepare("SELECT * from drivers_history
where drivers_history.plate_no = ?");
$stmt->bind_param("s", $plate_no);
if ($stmt->execute()) {
// $user = $stmt->get_result()->fetch_assoc();
// $stmt->close();
// return $user;
$result = $stmt->get_result();
$usersArr = array();
while ($user = $result->fetch_assoc()){
$usersArr[] = $user;
}
$stmt->close();
return $usersArr;
} else {
return NULL;
}
}
....
GetdriverFunction.php用于访问上面的函数：
...........
<?php
include './DbHandler.php';
$db = new DBHandler();
// json response array
$response = array("error" => FALSE);
if (isset($_POST['plate_no'])) {
// receiving the post params
$plate_no = $_POST['plate_no'];
$usersArr = $db->getDriverHistory($plate_no);
if ($usersArr != false) {
$response["error"]= FALSE;
$response["user"] = $usersArr;
echo json_encode($response);
}
}
......
最后用Java部分方法获取所有结果，其中plate_no等于某个plate_no：
private void GetParkingInfo(final String plate_no) {
// Tag used to cancel the request
String tag_string_req = "req_Verfication";
progressBarList.setVisibility(View.VISIBLE);
// myList.setVisibility(View.GONE);
StringRequest strReq = new StringRequest(Request.Method.POST,
Urls.URL_driver_parking_information, new
Response.Listener<String>() {
@Override
public void onResponse(String response) {
Log.d(TAG, "cerfication Response: " + response.toString());
// Parsing json
JSONArray jsonArrayResult ;
for (int i = 0; i < response.length(); i++) {
try {
JSONObject jObj = new JSONObject(response);
boolean error = jObj.getBoolean("error");
// Check for error node in json
if (!error) {
// user successfully exist in database
jsonArrayResult = jObj.getJSONArray("user");
for(int x=0; x<jsonArrayResult.length();x++){
JSONObject json = jsonArrayResult.getJSONObject(x);
String paid_amount = json.getString("paid_amount");
String parking_duration =
json.getString("parking_duration");
String parking_name = json.getString("parking_name");
HashMap<String, String> prodHashMap = new
HashMap<String, String>();
prodHashMap.put("paid_amount", paid_amount);
prodHashMap.put("parking_duration", parking_duration);
prodHashMap.put("parking_name", parking_name);
ArrayList<HashMap<String, String>> wordList;
wordList = new ArrayList<HashMap<String, String>>();
wordList.add(prodHashMap);
userList = wordList ;
}
ShowListData();
progressBarList.setVisibility(View.GONE);
}
else{
// Error in login. Get the error message
// // hiding the progress bar
progressBarList.setVisibility(View.GONE);
myList.setVisibility(View.VISIBLE);
String errorMsg = jObj.getString("error_msg");
Toast.makeText(getApplicationContext(), errorMsg,
Toast.LENGTH_LONG).show();
}
} catch (JSONException e) {
// JSON error
e.printStackTrace();
Toast.makeText(getApplicationContext(), "Json error: " +
e.getMessage(), Toast.LENGTH_LONG).show();
// // hiding the progress bar
progressBarList.setVisibility(View.GONE);
myList.setVisibility(View.VISIBLE);
}
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.e(TAG, "Verfication error Error: " + error.getMessage());
Toast.makeText(getApplicationContext(),
"response error", Toast.LENGTH_LONG).show();
// Toast.makeText(getApplicationContext(),
// error.getMessage(), Toast.LENGTH_LONG).show();
// hiding the progress bar
progressBarList.setVisibility(View.GONE);
myList.setVisibility(View.VISIBLE);
}
}) {
@Override
protected Map<String, String> getParams() {
// Posting parameters to verfication url
Map<String, String> params = new HashMap<String, String>();
params.put("plate_no", plate_no);
return params;
}
};
// // Adding request to request queue
AppController.getInstance().addToRequestQueue(strReq,tag_string_req);
}