handled breaking news

Author: sijan8s3

app/src/main/AndroidManifest.xml

@@ -2,6 +2,8 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="com.sijanneupane.mvvmnews">
 
+    <uses-permission android:name="android.permission.INTERNET"/>
+
     <application
         android:allowBackup="true"
         android:icon="@mipmap/ic_launcher"

app/src/main/java/com/sijanneupane/mvvmnews/repository/NewsRepository.kt

@@ -1,8 +1,17 @@
 package com.sijanneupane.mvvmnews.repository
 
+import com.sijanneupane.mvvmnews.api.RetrofitInstance
 import com.sijanneupane.mvvmnews.db.ArticleDatabase
-
+/*
+get data from database and from remote data source (retrofit api)
+ */
 class NewsRepository(
     val db: ArticleDatabase //parameter
 ) {
+
+    /*
+    function that directly queries our api for the breaking news
+     */
+    suspend fun getBreakingNews(countryCode:String, pageNumber:Int)=
+        RetrofitInstance.api.getBreakingNews(countryCode, pageNumber)
 }

app/src/main/java/com/sijanneupane/mvvmnews/ui/NewsViewModel.kt

@@ -1,9 +1,50 @@
 package com.sijanneupane.mvvmnews.ui
 
+import androidx.lifecycle.MutableLiveData
 import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import com.sijanneupane.mvvmnews.models.NewsResponse
 import com.sijanneupane.mvvmnews.repository.NewsRepository
+import com.sijanneupane.mvvmnews.utils.Resource
+import kotlinx.coroutines.launch
+import retrofit2.Response
 
 class NewsViewModel(
     val newsRepository: NewsRepository //parameter
 ) : ViewModel(){
+
+    //LIVEDATA OBJECT
+    val breakingNews: MutableLiveData<Resource<NewsResponse>> = MutableLiveData()
+    //Pagination
+    var breakingNewsPage= 1
+
+    init {
+        getBreakingNews("in")
+    }
+
+    //we cannot start the function in the coroutine so we start the it here
+    /*
+    viewModelScope makes the function alive only as long as the ViewModel is alive
+     */
+    fun getBreakingNews(countryCode: String)= viewModelScope.launch {
+        breakingNews.postValue(Resource.Loading()) //init loading state before the network call
+
+        //actual response
+        val response= newsRepository.getBreakingNews(countryCode, breakingNewsPage)
+
+        //handling response
+        breakingNews.postValue(handleBreakingNewsResponse(response))
+
+
+    }
+
+    private fun handleBreakingNewsResponse(response: Response<NewsResponse>): Resource<NewsResponse>{
+        if (response.isSuccessful){
+            response.body()?.let { resultResponse ->
+                return  Resource.Success(resultResponse)
+            }
+        }
+        return Resource.Error(response.message())
+    }
+
 }

app/src/main/java/com/sijanneupane/mvvmnews/ui/fragments/BreakingNewsFragment.kt

@@ -1,21 +1,69 @@
 package com.sijanneupane.mvvmnews.ui.fragments
 
 import android.os.Bundle
+import android.util.Log
 import android.view.View
+import android.widget.LinearLayout
 import androidx.fragment.app.Fragment
+import androidx.lifecycle.Observer
 import androidx.lifecycle.viewModelScope
+import androidx.recyclerview.widget.LinearLayoutManager
 import com.sijanneupane.mvvmnews.R
+import com.sijanneupane.mvvmnews.adapters.NewsAdapter
 import com.sijanneupane.mvvmnews.ui.MainActivity
 import com.sijanneupane.mvvmnews.ui.NewsViewModel
+import com.sijanneupane.mvvmnews.utils.Resource
+import kotlinx.android.synthetic.main.fragment_breaking_news.*
 
 class BreakingNewsFragment : Fragment(R.layout.fragment_breaking_news) {
     lateinit var viewModel: NewsViewModel
+    lateinit var newsAdapter: NewsAdapter
+
+    val TAG= "BreakingNewsFragment"
 
     override fun onViewCreated(view: View, savedInstanceState: Bundle?) {
         super.onViewCreated(view, savedInstanceState)
 
         //set viewModels to fragment activity
         //and we cast that as MainActivity so that we can have access to the view model created at MainActivity
         viewModel= (activity as MainActivity).viewModel
+
+        setupRecyclerView()
+
+        //subscribe to live data
+        viewModel.breakingNews.observe(viewLifecycleOwner, Observer { response->
+            when(response){
+                is Resource.Success->{
+                    hideProgressBar()
+                    //check null
+                    response.data?.let { newsResponse ->
+                        newsAdapter.differ.submitList(newsResponse.articles)
+                    }
+                }
+                is Resource.Error->{
+                    hideProgressBar()
+                    response.message?.let { message->
+                        Log.e(TAG, "An error occured: $message" )
+                    }
+                }
+                is Resource.Loading->{
+                    showProgressBar()
+                }
+            }
+        })
+    }
+
+    private fun setupRecyclerView(){
+        newsAdapter= NewsAdapter()
+        rvBreakingNews.apply {
+            adapter = newsAdapter
+            layoutManager = LinearLayoutManager(activity)
+        }
+    }
+    private fun hideProgressBar(){
+        paginationProgressBar.visibility= View.INVISIBLE
+    }
+    private fun showProgressBar(){
+        paginationProgressBar.visibility= View.VISIBLE
     }
 }