因此，我一直在尝试寻找一种方法来保存从API中获得的访问令牌。我可以从API成功获取JSON响应，并将其存储在result中的doInBackground变量中。
但是，由于某种原因，它没有保存在我的onPostExecute的SharedPreferences中。
result变量包含此JSON字符串{"access_token":"4Oq6o8oAGRf4oflu3hrbsy18qeIfG1","expires_in":36000,"token_type":"Bearer","scope":"read write","refresh_token":"iocSNJ2PTVbph2RnWmcf0Zv69PDKjw"}，该字符串是我从API收到的。
我有一种算法，目前应该只保存access_token。
我的代码如下：
WSAdapter.java
public class WSAdapter {
static public class SendAPIRequests extends AsyncTask<String, String, String> {
// Add a pre-execute thing
SharedPreferences ShPreference;
SharedPreferences.Editor PrefEditor;
static String MyPREFERENCES = "API Authentication";
String accessToken = "Access Token";
private WeakReference<Context> mLoginReference;
// constructor
public SendAPIRequests(Context context){
mLoginReference = new WeakReference<>(context);
}
@Override
protected String doInBackground(String... params) {
Thread.currentThread().setPriority(Thread.MAX_PRIORITY);
Log.e("TAG", params[0]);
Log.e("TAG", params[1]);
//String data = "";
StringBuilder result = new StringBuilder();
HttpURLConnection httpURLConnection = null;
try {
// Sets up connection to the URL (params[0] from .execute in "login")
httpURLConnection = (HttpURLConnection) new URL(params[2]).openConnection();
// Sets the request method for the URL
httpURLConnection.setRequestMethod("POST");
httpURLConnection.setRequestProperty("Content-Type", "application/json;charset=UTF-8");
httpURLConnection.setRequestProperty("Accept","application/json");
// Tells the URL that I am sending a POST request body
httpURLConnection.setDoOutput(true);
// Tells the URL that I want to read the response data
httpURLConnection.setDoInput(true);
// JSON object for the REST API
JSONObject jsonParam = new JSONObject();
jsonParam.put("client_id", "mYIHBd321Et3sgn7DqB8urnyrMDwzDeIJxd8eCCE");
jsonParam.put("client_secret", "qkFYdlvikU4kfhSMBoLNsGleS2HNVHcPqaspCDR0Wdrdex5dHyiFHPXctedNjugnoTq8Ayx7D3v1C1pHeqyPh1BjRlBTQiJYSuH6pi9EVeuyjovxacauGVeGdsBOkHI3");
jsonParam.put("username", params[0]);
jsonParam.put("password", params[1]);
jsonParam.put("grant_type", "password");
Log.i("JSON", jsonParam.toString());
// To write primitive Java data types to an output stream in a portable way
DataOutputStream wr = new DataOutputStream(httpURLConnection.getOutputStream());
// Writes out a byte to the underlying output stream of the data posted from .execute function
wr.writeBytes(jsonParam.toString());
// Flushes the jsonParam to the output stream
wr.flush();
wr.close();
// // Representing the input stream
InputStream in = new BufferedInputStream(httpURLConnection.getInputStream());
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
// reading the input stream / response from the url
String line;
while ((line = reader.readLine()) != null) {
result.append(line);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
// Disconnects socket after using
if (httpURLConnection != null) {
httpURLConnection.disconnect();
}
}
Log.e("TAG", result.toString());
return result.toString();
}
@Override
protected void onPostExecute(String result) {
//super.onPostExecute(result);
// expecting a response code fro my server upon receiving the POST data
Log.e("TAG", result);
// retrieves the context passed
Context context = mLoginReference.get();
ShPreference = context.getSharedPreferences(MyPREFERENCES, Context.MODE_PRIVATE);
// edits shared preferences for authentication and authorization
PrefEditor = ShPreference.edit();
// to save the Access Token from the API
try {
JSONObject pJObject = new JSONObject(result);
PrefEditor.putString(accessToken, pJObject.getString("access_token"));
PrefEditor.apply();
// algorithm for parsing the JSONArray from the Django REST API
/*for (int i = 0; i < pJObjArray.length(); i++) {
// puts the current iterated JSON object from the array to another temporary object
JSONObject pJObj_data = pJObjArray.getJSONObject(i);
PrefEditor.putString(accessToken, pJObj_data.getString("access_token"));
PrefEditor.apply();
}*/
} catch (JSONException e) {
//Toast.makeText(JSonActivity.this, e.toString(), Toast.LENGTH_LONG).show();
Log.d("Json","Exception = "+e.toString());
}
}
}
下面的代码包含读取SharedPreferences的代码。哪个应该在此AsyncTask的doInBackground中，因为我需要将access_token放在标题中。
应该在同一个班上。
public class SendPostsRequest extends AsyncTask<String, String, String> {
TextView postsSect;
// Add a pre-execute thing
HttpURLConnection urlConnection;
// gets the activity context
private WeakReference<Context> mPostReference;
// to be able to access activity resources
Activity activity;
SharedPreferences ShPreference;
SharedPreferences.Editor PrefEditor;
String accessToken = "Access Token";
// constructor
public SendPostsRequest(Context context, Activity activity){
mPostReference = new WeakReference<>(context);
this.activity = activity;
}
@Override
protected String doInBackground(String... params) {
StringBuilder result = new StringBuilder();
// retrieves the context passed
Context context = mPostReference.get();
ShPreference = context.getSharedPreferences(MyPREFERENCES, Context.MODE_PRIVATE);
String APIAuthentication = "Bearer " + ShPreference.getString(accessToken, "");
try {
// Sets up connection to the URL (params[0] from .execute in "login")
urlConnection = (HttpURLConnection) new URL(params[0]).openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setRequestProperty ("Authorization", APIAuthentication);
urlConnection.connect();
InputStream in = new BufferedInputStream(urlConnection.getInputStream());
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
String line;
while ((line = reader.readLine()) != null) {
result.append(line);
}
}catch( Exception e) {
e.printStackTrace();
}
finally {
urlConnection.disconnect();
}
return result.toString();
}
@Override
protected void onPostExecute(String result) {
// expecting a response code fro my server upon receiving the POST data
Log.e("TAG", result);
// gets the JSON files stored in the posts details class from Posts Activity
Posts.PostsDetails postsHelper = new Posts().new PostsDetails();
// retrieves the context passed
Context context = mPostReference.get();
// For posts
try {
JSONArray pJObjArray = new JSONArray(result);
// algorithm for parsing the JSONArray from the Django REST API
for (int i = 0; i < pJObjArray.length(); i++) {
// puts the current iterated JSON object from the array to another temporary object
JSONObject pJObj_data = pJObjArray.getJSONObject(i);
// inputs necesarry elements to the ListPosts function
postsHelper.setPost(pJObj_data.getInt("id"), pJObj_data.getString("post_title"), pJObj_data.getString("post_content"));
}
} catch (JSONException e) {
//Toast.makeText(JSonActivity.this, e.toString(), Toast.LENGTH_LONG).show();
Log.d("Json","Exception = "+e.toString());
}
// checks if context is not null before updating posts page
if (context != null){
postsSect = (TextView) activity.findViewById(R.id.PostsSection);
int lastFrJSONArray = postsHelper.getPostID().size() - 1;
// outputs the id of the very first post, something to put to the textview
postsSect.setText("id: " + postsHelper.getPostID().get(lastFrJSONArray - 2) + "\n");
for (int i = lastFrJSONArray; i >= 0; i--)
{
// appending the titles and contents of the current post
postsSect.append("title: " + postsHelper.getPostTitle().get(i) + "\n");
postsSect.append("content: " + postsHelper.getPostContent().get(i) + "\n");
// if this is the last post, then don't need to append id for the next post.
if (i != 0) {
postsSect.append("id: " + postsHelper.getPostID().get(i) + "\n");
}
}
}
}
}
更新：
我已经编辑了JSON解析算法。
现在，此代码不再将result中的JSON对象解析为数组，而是将其解析为对象。应当将JSONarray算法注释掉。
答案 0 :(得分：0)
您从Web服务获得的响应实际上不是JSONArray，而是简单的JSONObject。因此更改此行：
JSONArray pJObjArray = new JSONArray(result);
到
JSONObject pJObjArray = new JSONObject(result);
答案 1 :(得分：0)
如果您没有获得令牌，请遵循以下代码。它可能会帮助您。
//member variable
SharedPreferences ShPreference;
SharedPreferences.Editor PrefEditor;
String ApiToken;
OnCreate(){
ShPreference = context.getSharedPreferences(MyPREFERENCES, Context.MODE_PRIVATE);
ApiToken = ShPreference.getString(accessToken, "");
// call wherever you want
new SendPostsRequest(ApiToken).execute()
}
public class SendPostsRequest extends AsyncTask<String, String, String> {
private String APIToken;
TextView postsSect;
// Add a pre-execute thing
HttpURLConnection urlConnection;
// gets the activity context
// constructor
public SendPostsRequest(String APIToken){
this.APIToken = APIToken;
}
@Override
protected String doInBackground(String... params) {
StringBuilder result = new StringBuilder();
// retrieves the context passed
Context context = mPostReference.get();
String APIAuthentication = APIToken; // or you can direct pass
try {
// Sets up connection to the URL (params[0] from .execute in "login")
urlConnection = (HttpURLConnection) new URL(params[0]).openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setRequestProperty ("Authorization", APIAuthentication);
urlConnection.connect();
InputStream in = new BufferedInputStream(urlConnection.getInputStream());
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
String line;
while ((line = reader.readLine()) != null) {
result.append(line);
}
}catch( Exception e) {
e.printStackTrace();
}
finally {
urlConnection.disconnect();
}
return result.toString();
}
@Override
protected void onPostExecute(String result) {
// expecting a response code fro my server upon receiving the POST data
Log.e("TAG", result);
// gets the JSON files stored in the posts details class from Posts Activity
Posts.PostsDetails postsHelper = new Posts().new PostsDetails();
// retrieves the context passed
Context context = mPostReference.get();
// For posts
try {
JSONArray pJObjArray = new JSONArray(result);
// algorithm for parsing the JSONArray from the Django REST API
for (int i = 0; i < pJObjArray.length(); i++) {
// puts the current iterated JSON object from the array to another temporary object
JSONObject pJObj_data = pJObjArray.getJSONObject(i);
// inputs necesarry elements to the ListPosts function
postsHelper.setPost(pJObj_data.getInt("id"), pJObj_data.getString("post_title"), pJObj_data.getString("post_content"));
}
} catch (JSONException e) {
//Toast.makeText(JSonActivity.this, e.toString(), Toast.LENGTH_LONG).show();
Log.d("Json","Exception = "+e.toString());
}
// checks if context is not null before updating posts page
if (context != null){
postsSect = (TextView) activity.findViewById(R.id.PostsSection);
int lastFrJSONArray = postsHelper.getPostID().size() - 1;
// outputs the id of the very first post, something to put to the textview
postsSect.setText("id: " + postsHelper.getPostID().get(lastFrJSONArray - 2) + "\n");
for (int i = lastFrJSONArray; i >= 0; i--)
{
// appending the titles and contents of the current post
postsSect.append("title: " + postsHelper.getPostTitle().get(i) + "\n");
postsSect.append("content: " + postsHelper.getPostContent().get(i) + "\n");
// if this is the last post, then don't need to append id for the next post.
if (i != 0) {
postsSect.append("id: " + postsHelper.getPostID().get(i) + "\n");
}
}
}
}
}