/ RecyclerView

A simple Recycler view adapter with pagination

A simple Recycler view adapter with pagination

PrettyListView

Because Life is too short for duplicating Recyclerview code, PrettylistView introduce a very simple generic adapter, pagination handling with customized views (Error,loading) and updating via diffUtils.

Enough talking let's see how to use it .

Installation

  • Step 1. Add the JitPack repository to your build file

allprojects {
		repositories {
			...
			maven { url 'https://jitpack.io' }
		}
	}
  • Step 2. Add the dependency

 	dependencies {
	        implementation 'com.github.Rohyme:PrettyListView:2.0.0'
		}

Usage :

  1. Get your view
 val prettyList =  findViewById<RecyclerView>(R.id.testListView)
  1. Build your adapter using
 val myAdapterBuilder = BaseListAdapter.with<TestModel>(prettyList)
  1. Make instance of class implementing MainHolderInterface<T> to set your adapter specification in .

    val holderInterfaceInstance = object : MainHolderInterface<TestModel> {
          
           // Mandatory
          // return the instance of your list that will be used in your list view
        override fun getList(): ArrayList<TestModel?> {
             return testListData
        }
          
          // Mandatory
          // return the layout of your list view item
        override fun getView(type: Int): Int {
           return R.layout.test_list_item
        }
    
          // Mandatory
          // Here you can use your model item data for your list item view 
        override fun getViewData(holder: RecyclerView.ViewHolder, t: TestModel,             position: Int) {
            
         val listItemView = holder.itemView
         val listItemText = listItemView.findViewById<RecyclerView>(R.id.testListView)
         listItemText.text = t.text
       }
    
          // Optional 
          // For itemViewTypes 
        override fun getItemViewType(position: Int): Int {
                    return super.getItemViewType(position)
       }
    
    }
    
    

    Note : Don't use (-30 , -31) as Item view types constants Because they are already taken for Loading & Error items of pagination

  2. Then set your holderInterface instance to your adapter builder

    myAdapterBuilder.setAdapter(holderInterfaceInstance)
    
  3. For using pagination

    val myPaginationBuilder = myAdapterBuilder.hasPaginated() //return PaginationBuilder instance
    
  4. Configure your pagination

    myPaginationBuilder.setErrorLayout(R.layout.error_layout)
                       .setLoadingLayout(R.layout.loading_layout)
    				   .setVisibleThreshold(5)
    
  5. Get your final adapter

    mAdapter = myAdapterBuilder.adapterDone()
    
  6. Set list and pagination calls & callbacks :

    • setListCallBacks Used to notify if items count in recycler view changed :
    mAdapter.setListCallBacks(object : ListUtilsCallbacks<TestModel> {
        override fun onDataCountChanged(itemCount: Int) {
            Log.i("MyListView","list item count = $itemCount")
        }
    })
    
    • setPaginationListener Used for pagination callbacks :

      val paginationListener = object : ListPaginationListener {
          override fun onLoadMore(page: Int, totalItemCount: Int, listView: RecyclerView) {
             getlist(page)
          }
      
        //Optional
          override fun onError(errorView: View) {
              errorView.setOnClickListener {
                  retryGettingList()
              }
          }
      
          //Optional 
          //get the view of your loading view to make any action on it
          override fun onLoading(loadingView: View) {
              val progressText = view.findViewById<TextView>(R.id.progressText)
          	val progressText.text = "Loading new Item"
          }
      }
      
    • Pagination Calls

      • mAdapter.paginatedDataAdded() used when new paginated data added.

      • mAdapter.paginationDone() used when there is no more items for pagination.

      • mAdapter.paginationError() used to show pagination error item.

      • mAdapter.paginationNormalState() used to hide loading or error pagination item.

      • mAdapter.paginationLoading() used to show pagination loading item.

  7. You have 3 ways to update your list

    • You can make change to testListData returned in the mainHolderInstance then call mAdatper.updateList()
      e.g :

      testListData.add(TestModel("new test"))
      mAdapter.update()
      
    • You can use Observable list instead of your list instance and any change happened in it will be updated automatically .
      e.g :

      // global field
      var testListData: ObservableArrayList<TestModel> = ObservableArrayList()
      
      // in your holderInstance 
      override fun getList(): ArrayList<TestModel?> {
                      return testListData
                  }
      
      // updating
      testListData.add(TestModel("new test in observable list"))
      
    • You can use update list with just passing a list from the same type in order not to change your original data in testListData . It could be useful for filtering or searching.
      e.g:

       searchField.addTextChangedListener(object : TextWatcher {
                  override fun afterTextChanged(s: Editable?) {
                  }
                  override fun beforeTextChanged(s: CharSequence?, start: Int, count: Int, after: Int) {
                  }
      
                  override fun onTextChanged(s: CharSequence?, start: Int, before:Int, count: Int) {
                      mAdapter.updateList(ArrayList(testListData.filter {
                          it?.text?.contains(s.toString()) ?: false
                      }))
                  }
              })
      

GitHub