Java tutorial
/* * Copyright 2016 Bobby * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package in.codehex.facilis; import com.android.volley.AuthFailureError; import com.android.volley.NetworkResponse; import com.android.volley.Request; import com.android.volley.Response; import com.android.volley.VolleyError; import com.android.volley.toolbox.StringRequest; import com.squareup.picasso.Picasso; import org.json.JSONArray; import org.json.JSONException; import org.json.JSONObject; import android.content.Context; import android.content.SharedPreferences; import android.os.Bundle; import android.support.v4.app.Fragment; import android.support.v4.widget.SwipeRefreshLayout; import android.support.v7.widget.DefaultItemAnimator; import android.support.v7.widget.LinearLayoutManager; import android.support.v7.widget.RecyclerView; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.ImageView; import android.widget.TextView; import android.widget.Toast; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import in.codehex.facilis.app.AppController; import in.codehex.facilis.app.Config; import in.codehex.facilis.app.ItemClickListener; import in.codehex.facilis.helper.CircleTransform; import in.codehex.facilis.model.OrderItem; /** * A fragment that is used to display last minute deals list in the {@link ViewOrdersFragment} * class. */ public class LastMinuteFragment extends Fragment { SwipeRefreshLayout mRefreshLayout; RecyclerView mRecyclerView; List<OrderItem> mOrderItemList; ViewOrdersAdapter mAdapter; SharedPreferences userPreferences; LinearLayoutManager mLayoutManager; int mCount = 0; boolean isEnded = false; int firstVisibleItem, visibleItemCount, totalItemCount; int previousTotal = 0; boolean loading = true; int visibleThreshold = 5; public LastMinuteFragment() { // Required empty public constructor } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { // Inflate the layout for this fragment View view = inflater.inflate(R.layout.fragment_last_minute, container, false); initObjects(view); prepareObjects(); return view; } /** * Initialize the objects. * * @param view the root view of the layout. */ private void initObjects(View view) { mRefreshLayout = (SwipeRefreshLayout) view.findViewById(R.id.refresh); mRecyclerView = (RecyclerView) view.findViewById(R.id.last_minute_list); mOrderItemList = new ArrayList<>(); mLayoutManager = new LinearLayoutManager(getContext()); mAdapter = new ViewOrdersAdapter(getContext(), mOrderItemList); userPreferences = getActivity().getSharedPreferences(Config.PREF_USER, Context.MODE_PRIVATE); } /** * Implement and manipulate the objects. */ private void prepareObjects() { mRecyclerView.setAdapter(mAdapter); mRecyclerView.setLayoutManager(mLayoutManager); mRecyclerView.setHasFixedSize(true); mRecyclerView.setItemAnimator(new DefaultItemAnimator()); mRecyclerView.addOnScrollListener(new RecyclerView.OnScrollListener() { @Override public void onScrolled(RecyclerView recyclerView, int dx, int dy) { super.onScrolled(recyclerView, dx, dy); visibleItemCount = mRecyclerView.getChildCount(); totalItemCount = mLayoutManager.getItemCount(); firstVisibleItem = mLayoutManager.findFirstVisibleItemPosition(); if (loading) { if (totalItemCount > previousTotal) { loading = false; previousTotal = totalItemCount; } } if (!loading && (totalItemCount - visibleItemCount) <= (firstVisibleItem + visibleThreshold)) { processOrders(); loading = true; } } }); mRefreshLayout.setColorSchemeColors(R.color.primary, R.color.primary_dark, R.color.accent); mRefreshLayout.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() { @Override public void onRefresh() { resetData(); mRefreshLayout.setRefreshing(true); processOrders(); } }); mRefreshLayout.post(new Runnable() { @Override public void run() { resetData(); mRefreshLayout.setRefreshing(true); processOrders(); } }); } /** * Reset the count for all the integers and values of booleans to default. */ private void resetData() { mCount = 0; previousTotal = 0; loading = true; isEnded = false; } /** * Fetch the last minute deals list from the server. */ private void processOrders() { final JSONObject jsonObject = new JSONObject(); try { jsonObject.put(Config.KEY_API_DEAL_TYPE, "last_minute"); jsonObject.put(Config.KEY_API_START, mCount); jsonObject.put(Config.KEY_API_END, mCount + 10); } catch (JSONException e) { // TODO: remove toast Toast.makeText(getContext(), "Error occurred while generating data - " + e.getMessage(), Toast.LENGTH_SHORT).show(); } StringRequest stringRequest = new StringRequest(Request.Method.POST, Config.API_HOME_PAGE_DEALS, new Response.Listener<String>() { @Override public void onResponse(String response) { if (mCount == 0) { mOrderItemList.clear(); mAdapter.notifyDataSetChanged(); } mRefreshLayout.setRefreshing(false); try { JSONArray jsonArray = new JSONArray(response); if (jsonArray.length() < 10) isEnded = true; if (!isEnded) { for (int i = 0; i < jsonArray.length(); i++) { JSONObject object = jsonArray.getJSONObject(i); int id = object.getInt(Config.KEY_API_ID); int orderId = object.getInt(Config.KEY_API_ORDER_ID); JSONObject postedByObject = object.getJSONObject(Config.KEY_API_POSTED_BY); int postedById = postedByObject.getInt(Config.KEY_API_POSTED_BY_ID); String postedByFirstName = postedByObject .getString(Config.KEY_API_POSTED_BY_FIRST_NAME); String postedByLastName = postedByObject .getString(Config.KEY_API_POSTED_BY_LAST_NAME); String postedDate = object.getString(Config.KEY_API_POSTED_DATE); String days = object.getString(Config.KEY_API_DAYS); int leastCost = object.getInt(Config.KEY_API_LEAST_COST); int average = object.getInt(Config.KEY_API_AVERAGE); int counter = object.getInt(Config.KEY_API_COUNTER); String userImg = object.getString(Config.KEY_API_USER_IMAGE); mOrderItemList.add(mCount + i, new OrderItem(id, orderId, postedById, leastCost, average, counter, postedByFirstName, postedByLastName, postedDate, days, userImg)); mAdapter.notifyItemInserted(mCount + i); } mCount = mCount + 10; } } catch (JSONException e) { // TODO: remove toast Toast.makeText(getContext(), "Error occurred while parsing data - " + e.getMessage(), Toast.LENGTH_SHORT).show(); } } }, new Response.ErrorListener() { @Override public void onErrorResponse(VolleyError error) { mRefreshLayout.setRefreshing(false); NetworkResponse response = error.networkResponse; try { byte[] bytes = response.data; String data = new String(bytes); if (response.statusCode == 400) { JSONObject errorObject = new JSONObject(data); int mError = errorObject.getInt(Config.KEY_API_ERROR); String mMessage = errorObject.getString(Config.KEY_API_MESSAGE); if (mError == 400) isEnded = true; // TODO: remove toast Toast.makeText(getContext(), mMessage, Toast.LENGTH_SHORT).show(); } else if (response.statusCode == 401) { JSONObject errorObject = new JSONObject(data); String errorData = errorObject.getString(Config.KEY_API_DETAIL); // TODO: remove toast Toast.makeText(getContext(), errorData, Toast.LENGTH_SHORT).show(); } } catch (JSONException e) { // TODO: remove toast Toast.makeText(getContext(), "Error occurred while parsing data - " + e.getMessage(), Toast.LENGTH_SHORT).show(); } catch (NullPointerException e) { // TODO: remove toast Toast.makeText(getContext(), "Network error - " + e.getMessage(), Toast.LENGTH_SHORT) .show(); } } }) { @Override public Map<String, String> getHeaders() throws AuthFailureError { Map<String, String> headers = new HashMap<>(); headers.put("Authorization", "Token " + userPreferences.getString(Config.KEY_PREF_TOKEN, null)); return headers; } @Override public byte[] getBody() throws AuthFailureError { return jsonObject.toString().getBytes(); } @Override public String getBodyContentType() { return "application/json; charset=utf-8"; } }; AppController.getInstance().addToRequestQueue(stringRequest, "last_minute"); } /** * View adapter for the recycler view of the view orders list item. */ private class ViewOrdersAdapter extends RecyclerView.Adapter<ViewOrdersAdapter.ViewOrdersHolder> { Context context; List<OrderItem> mOrderItemList; public ViewOrdersAdapter(Context context, List<OrderItem> mOrderItemList) { this.context = context; this.mOrderItemList = mOrderItemList; } @Override public ViewOrdersHolder onCreateViewHolder(ViewGroup parent, int viewType) { View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_order, parent, false); return new ViewOrdersHolder(view); } @Override public void onBindViewHolder(ViewOrdersHolder holder, int position) { final OrderItem orderItem = mOrderItemList.get(position); String name = orderItem.getPostedByFirstName() + " " + orderItem.getPostedByLastName(); String dp = orderItem.getUserImg(); String duration = String.valueOf(orderItem.getDays()) + " left"; String posted = String.valueOf(orderItem.getPostedDate()); String item = String.valueOf(orderItem.getCounter()) + " items"; holder.textName.setText(name); Picasso.with(context).load(dp).placeholder(R.drawable.ic_person).transform(new CircleTransform()) .into(holder.imgDp); holder.textDuration.setText(duration); holder.textPosted.setText(posted); holder.textItem.setText(item); holder.setClickListener(new ItemClickListener() { @Override public void onClick(View view, int position, boolean isLongClick) { ((MainActivity) getActivity()).showOrderItems(Config.KEY_FRAGMENT_LAST_MINUTE, orderItem.getOrderId()); } }); } @Override public int getItemCount() { return mOrderItemList.size(); } protected class ViewOrdersHolder extends RecyclerView.ViewHolder implements View.OnClickListener { private TextView textName, textDuration, textPosted, textItem; private ImageView imgDp; private ItemClickListener itemClickListener; public ViewOrdersHolder(View view) { super(view); textName = (TextView) view.findViewById(R.id.text_name); textDuration = (TextView) view.findViewById(R.id.text_duration); textPosted = (TextView) view.findViewById(R.id.text_posted); textItem = (TextView) view.findViewById(R.id.text_item); imgDp = (ImageView) view.findViewById(R.id.img_dp); view.setOnClickListener(this); } public void setClickListener(ItemClickListener itemClickListener) { this.itemClickListener = itemClickListener; } @Override public void onClick(View view) { itemClickListener.onClick(view, getAdapterPosition(), false); } } } }