I have enabled Volley caching to view data in offline mode also. JSON data is updated with certain time period. But I can't update new json data with SwipeRefreshLayout
. If I removed Volley caching code, data is refreshed. I want to expire old cache and load new cache while clicking refresh button.
I have the following code to refresh.
mSwipeRefreshLayout = (SwipeRefreshLayout) findViewById(R.id.swipeRefreshLayout);
mSwipeRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
@Override
public void onRefresh() {
mExampleList.clear();
parseJSON();
mSwipeRefreshLayout.setRefreshing(true);
if (mSwipeRefreshLayout != null && mSwipeRefreshLayout.isRefreshing()) {
mSwipeRefreshLayout.setRefreshing(false); // This hides the spinner
}
}
});
mExampleList = new ArrayList<>();
mRequestQueue = Volley.newRequestQueue(this);
parseJSON();
Here's how I implemented JSON parsing and enabling volley cache.
private void parseJSON() {
String url = "http://fitandfineindustries.com/newsapi.php";
JsonObjectRequest request = new JsonObjectRequest(Request.Method.GET, url, null,
new Response.Listener<JSONObject>() {
@Override
public void onResponse(JSONObject response) {
try {
JSONArray jsonArray = response.getJSONArray("info");
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject hit = jsonArray.getJSONObject(i);
String creatorName = hit.getString("heading");
String img = hit.getString("img");
String imageUrl = img.length() == 0 ? "file:///android_asset/fitandfineindustries.jpg" : "http://fitandfineindustries.com/images/plan/"+img;
mExampleList.add(new NewsItem(imageUrl, creatorName));
}
mNewsAdapter = new NewsAdapter(AgroActivity.this, mExampleList);
mRecyclerView.setAdapter(mNewsAdapter);
mNewsAdapter.setOnItemClickListener(AgroActivity.this);
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
error.printStackTrace();
}
}){
@Override
protected Response<JSONObject> parseNetworkResponse(NetworkResponse response) {
try {
Cache.Entry cacheEntry = HttpHeaderParser.parseCacheHeaders(response);
if (cacheEntry == null) {
cacheEntry = new Cache.Entry();
}
final long cacheHitButRefreshed = 1 * 60 * 1000; // in 1 minutes cache will be hit, but also refreshed on background
final long cacheExpired = 24 * 60 * 60 * 1000; // in 24 hours this cache entry expires completely
long now = System.currentTimeMillis();
final long softExpire = now + cacheHitButRefreshed;
final long ttl = now + cacheExpired;
cacheEntry.data = response.data;
cacheEntry.softTtl = softExpire;
cacheEntry.ttl = ttl;
String headerValue;
headerValue = response.headers.get("Date");
if (headerValue != null) {
cacheEntry.serverDate = HttpHeaderParser.parseDateAsEpoch(headerValue);
}
headerValue = response.headers.get("Last-Modified");
if (headerValue != null) {
cacheEntry.lastModified = HttpHeaderParser.parseDateAsEpoch(headerValue);
}
cacheEntry.responseHeaders = response.headers;
final String jsonString = new String(response.data,
HttpHeaderParser.parseCharset(response.headers));
return Response.success(new JSONObject(jsonString), cacheEntry);
} catch (UnsupportedEncodingException e) {
return Response.error(new ParseError(e));
} catch (JSONException e) {
return Response.error(new ParseError(e));
}
}
@Override
protected void deliverResponse(JSONObject response) {
super.deliverResponse(response);
}
@Override
public void deliverError(VolleyError error) {
super.deliverError(error);
}
@Override
protected VolleyError parseNetworkError(VolleyError volleyError) {
return super.parseNetworkError(volleyError);
}
};
mRequestQueue.add(request);
}
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