Android – volley jsonobjectrequest sends header file in get request
•
Android
I tried to send some authentication headers from the get request, and I tried to call with volley jsonobjectrequest:
Map<String,String> params=new HashMap<String,String>();
params.put("token","fghjbvjhnjjk");
activity.showDialog();
JsonObjectRequest req = new JsonObjectRequest(Request.Method.GET,url,
new JSONObject(params), new Response.Listener<JSONObject>() {
@Override
public void onResponse(JSONObject response) {
Log.d(tag, response.toString());
activity.hideDialog();
try {
activity.onRequestServed(response, code);
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
@Override
public void one rrorResponse(VolleyError error) {
VolleyLog.d(tag, "Error: " + error.getMessage());
Log.e(tag, "Site Info Error: " + error.getMessage());
Toast.makeText(activity.getApplicationContext(),
error.getMessage(), Toast.LENGTH_SHORT).show();
activity.hideDialog();
try {
activity.onRequestServed(null,code);
} catch (JSONException e) {
e.printStackTrace();
}
}
});
req.setShouldCache(true);
But it shows:
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'int java.lang.String.hashCode()' on a null object reference
at com.android.volley.Request.<init>(Request.java:136)
at com.android.volley.tool@R_434_2419@.JsonRequest.<init>(JsonRequest.java:58)
at com.android.volley.tool@R_434_2419@.JsonObjectRequest.<init>(JsonObjectRequest.java:47)
I read somewhere that you can create a new jsonobject with this parameter by making a HashMap to pass the header file. Maybe this will apply to post requests. Please help
resolvent:
Well, it's very simple and precise. To pass the header to a get or post request, you need to override the getheaders method in the jsonobjectrequest class. How do you do this
JsonObjectRequest req = new JsonObjectRequest(Request.Method.GET,url,
null, new Response.Listener<JSONObject>() {
@Override
public void onResponse(JSONObject response) {
Log.d(tag, response.toString());
activity.hideDialog();
try {
activity.onRequestServed(response, code);
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
@Override
public void one rrorResponse(VolleyError error) {
VolleyLog.d(tag, "Error: " + error.getMessage());
Log.e(tag, "Site Info Error: " + error.getMessage());
Toast.makeText(activity.getApplicationContext(),
error.getMessage(), Toast.LENGTH_SHORT).show();
activity.hideDialog();
try {
activity.onRequestServed(null,code);
} catch (JSONException e) {
e.printStackTrace();
}
}
}) {
/**
* Passing some request headers
*/
@Override
public Map<String, String> getHeaders() throws AuthFailureError {
HashMap<String, String> headers = new HashMap<String, String>();
//headers.put("Content-Type", "application/json");
headers.put("key", "Value");
return headers;
}
};
The content of this article comes from the network collection of netizens. It is used as a learning reference. The copyright belongs to the original author.
THE END
二维码