search functionality added

Author: sijan8s3

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

@@ -14,4 +14,10 @@ class NewsRepository(
      */
     suspend fun getBreakingNews(countryCode:String, pageNumber:Int)=
         RetrofitInstance.api.getBreakingNews(countryCode, pageNumber)
+
+    /*
+    function that query our api for searched news
+     */
+    suspend fun searchNews(searchQuery: String, pageNumber: Int)=
+        RetrofitInstance.api.searchForNews(searchQuery, pageNumber)
 }

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

@@ -15,8 +15,11 @@ class NewsViewModel(
 
     //LIVEDATA OBJECT
     val breakingNews: MutableLiveData<Resource<NewsResponse>> = MutableLiveData()
+    val searchNews: MutableLiveData<Resource<NewsResponse>> = MutableLiveData()
+
     //Pagination
     var breakingNewsPage= 1
+    var searchNewsPage= 1
 
     init {
         getBreakingNews("in")
@@ -34,10 +37,20 @@ class NewsViewModel(
 
         //handling response
         breakingNews.postValue(handleBreakingNewsResponse(response))
+    }
+
+
+    fun searchNews(searchQuery: String)= viewModelScope.launch {
+        searchNews.postValue(Resource.Loading()) //init loading state before the network call
 
+        //actual response
+        val response= newsRepository.searchNews(searchQuery, searchNewsPage)
 
+        //handling response
+        searchNews.postValue(handleSearchNewsResponse(response))
     }
 
+
     private fun handleBreakingNewsResponse(response: Response<NewsResponse>): Resource<NewsResponse>{
         if (response.isSuccessful){
             response.body()?.let { resultResponse ->
@@ -47,4 +60,13 @@ class NewsViewModel(
         return Resource.Error(response.message())
     }
 
+    private fun handleSearchNewsResponse(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/SearchNewsFragment.kt

@@ -1,21 +1,90 @@
 package com.sijanneupane.mvvmnews.ui.fragments
 
 import android.os.Bundle
+import android.util.Log
 import android.view.View
+import androidx.core.widget.addTextChangedListener
 import androidx.fragment.app.Fragment
+import androidx.lifecycle.Observer
+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.Constants.Companion.SEARCH_DELAY
+import com.sijanneupane.mvvmnews.utils.Resource
+import kotlinx.android.synthetic.main.fragment_search_news.*
+import kotlinx.coroutines.Job
+import kotlinx.coroutines.MainScope
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.launch
 
 class SearchNewsFragment : Fragment (R.layout.fragment_search_news) {
 
     lateinit var viewModel: NewsViewModel
+    val TAG= "SearchNewsFragment"
+    lateinit var newsAdapter: NewsAdapter
 
     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()
+
+        //implementing search delay
+        var job: Job? = null
+        etSearch.addTextChangedListener {editable->
+            job?.cancel() //cancel current job
+
+            //new job
+            job= MainScope().launch {
+                delay(SEARCH_DELAY)
+
+                //after delay, check editable for null,
+                editable?.let {
+                    if (editable.toString().isNotEmpty()){
+                        viewModel.searchNews(editable.toString())
+                    }
+                }
+            }
+        }
+
+        //subscribe to live data
+        viewModel.searchNews.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()
+        rvSearchNews.apply {
+            adapter = newsAdapter
+            layoutManager = LinearLayoutManager(activity)
+        }
+    }
+    private fun hideProgressBar(){
+        paginationProgressBar.visibility= View.INVISIBLE
+    }
+    private fun showProgressBar(){
+        paginationProgressBar.visibility= View.VISIBLE
     }
 }

app/src/main/java/com/sijanneupane/mvvmnews/utils/Constants.kt

@@ -4,5 +4,6 @@ class Constants {
     companion object{
         const val API_KEY= "a7ebed0b55b041e7a20fc6ef542c5322"
         const val BASE_URL= "https://newsapi.org"
+        const val SEARCH_DELAY= 500L
     }
 }