我遇到了使用volley从web服务获取数据到spinner的问题。我的问题与 Android 7.0.1（模拟器）中的问题相同，但 Android 4.4中没有问题（真实设备）我现在该怎么办。请帮帮我。 我的代码就是这个
public class MainActivity extends AppCompatActivity implements Spinner.OnItemSelectedListener{
//Declaring an Spinner
private Spinner spinner;
//An ArrayList for Spinner Items
private ArrayList<String> students;
//JSON Array
private JSONArray result;
private RequestQueue requestQueue;
//TextViews to display details
private TextView textViewName;
private TextView textViewCourse;
private TextView textViewSession;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//Initializing the ArrayList
students = new ArrayList<String>();
//Initializing Spinner
spinner = (Spinner) findViewById(R.id.spinner);
//Adding an Item Selected Listener to our Spinner
//As we have implemented the class Spinner.OnItemSelectedListener to this class iteself we are passing this to setOnItemSelectedListener
spinner.setOnItemSelectedListener(this);
//Initializing TextViews
//This method will fetch the data from the URL
getData();
}
private void getData(){
//Creating a request queue
JsonObjectRequest StringRequest = new JsonObjectRequest(Config.DATA_URL, null,
new Response.Listener<JSONObject>() {
@Override
public void onResponse(JSONObject response) {
if (response != null) {
JSONObject j = null;
try {
//Parsing the fetched Json String to JSON Object
j = response;
//Storing the Array of JSON String to our JSON Array
result = j.getJSONArray(Config.JSON_ARRAY);
//Calling method getStudents to get the students from the JSON Array
getStudents(result);
} catch (JSONException e) {
e.printStackTrace();
}
}
}
},
new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
System.out.println("Volly error is this >>" + error);
}
});
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN
&& Build.VERSION.SDK_INT <= Build.VERSION_CODES.KITKAT) {
HttpStack stack = null;
try {
stack = new HurlStack(null, new TLSSocketFactory());
} catch (KeyManagementException e) {
e.printStackTrace();
Log.d("Your Wrapper Class", "Could not create new stack for TLS v1.2");
stack = new HurlStack();
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
Log.d("Your Wrapper Class", "Could not create new stack for TLS v1.2");
stack = new HurlStack();
}
requestQueue = Volley.newRequestQueue(getApplicationContext(), stack);
} else {
requestQueue = Volley.newRequestQueue(getApplicationContext());
}
requestQueue = Volley.newRequestQueue(this);
requestQueue.add(StringRequest);
}
private void getStudents(JSONArray j){
//Traversing through all the items in the json array
for(int i=0;i<j.length();i++){
try {
//Getting json object
JSONObject json = j.getJSONObject(i);
//Adding the name of the student to array list
students.add(json.getString(Config.TAG_USERNAME));
} catch (JSONException e) {
e.printStackTrace();
}
}
Log.e("student >>",students.toString());
//Setting adapter to show the items in the spinner
spinner.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, students));
}
//Method to get student name of a particular position
//this method will execute when we pic an item from the spinner
@Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
//Setting the values to textviews for a selected item
}
//When no item is selected this method would execute
@Override
public void onNothingSelected(AdapterView<?> parent) {
}
}
答案 0 :(得分：6)
我遇到了类似的问题，我的API调用可以在较新版本的Android中运行（我认为是21及以上版本），但不适用于旧版本。这是由于较新版本的Android仅支持较新版本的SSL。
为了克服这个问题，我们在初始化Volley Request Queue时需要更多设置：
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN
&& Build.VERSION.SDK_INT <= Build.VERSION_CODES.KITKAT) {
HttpStack stack = null;
try {
stack = new HurlStack(null, new TLSSocketFactory());
} catch (KeyManagementException e) {
e.printStackTrace();
Log.d("Your Wrapper Class", "Could not create new stack for TLS v1.2");
stack = new HurlStack();
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
Log.d("Your Wrapper Class", "Could not create new stack for TLS v1.2");
stack = new HurlStack();
}
requestQueue = Volley.newRequestQueue(context, stack);
} else {
requestQueue = Volley.newRequestQueue(context);
}
<强> TLSSocketFactory
public class TLSSocketFactory extends SSLSocketFactory {
private SSLSocketFactory internalSSLSocketFactory;
public TLSSocketFactory() throws KeyManagementException, NoSuchAlgorithmException {
SSLContext context = SSLContext.getInstance("TLS");
context.init(null, null, null);
internalSSLSocketFactory = context.getSocketFactory();
}
@Override
public String[] getDefaultCipherSuites() {
return internalSSLSocketFactory.getDefaultCipherSuites();
}
@Override
public String[] getSupportedCipherSuites() {
return internalSSLSocketFactory.getSupportedCipherSuites();
}
@Override
public Socket createSocket(Socket s, String host, int port, boolean autoClose) throws IOException {
return enableTLSOnSocket(internalSSLSocketFactory.createSocket(s, host, port, autoClose));
}
@Override
public Socket createSocket(String host, int port) throws IOException, UnknownHostException {
return enableTLSOnSocket(internalSSLSocketFactory.createSocket(host, port));
}
@Override
public Socket createSocket(String host, int port, InetAddress localHost, int localPort) throws IOException, UnknownHostException {
return enableTLSOnSocket(internalSSLSocketFactory.createSocket(host, port, localHost, localPort));
}
@Override
public Socket createSocket(InetAddress host, int port) throws IOException {
return enableTLSOnSocket(internalSSLSocketFactory.createSocket(host, port));
}
@Override
public Socket createSocket(InetAddress address, int port, InetAddress localAddress, int localPort) throws IOException {
return enableTLSOnSocket(internalSSLSocketFactory.createSocket(address, port, localAddress, localPort));
}
private Socket enableTLSOnSocket(Socket socket) {
if(socket != null && (socket instanceof SSLSocket)) {
((SSLSocket)socket).setEnabledProtocols(new String[] {"TLSv1.1", "TLSv1.2"});
}
return socket;
}
}
将TLSSocketFactory类添加到项目中，它应该完美无缺。
答案 1 :(得分：2)
private void updateAndroidSecurityProvider() {
try {
ProviderInstaller.installIfNeeded(this);
} catch (Exception e) {
e.getMessage();
}
}
在调用任何HTTP之前调用上面的方法。
和
在gradle中添加到库下面：
implementation 'com.google.android.gms:play-services-auth:11.8.0