RecyclerCalendarAndroid

A simple DIY library to generate your own custom Calendar View using RecyclerView, written in Kotlin

Step 1. Add the JitPack repository to your build file
Add it in your root build.gradle at the end of repositories:

allprojects {  
  repositories {
    ...
    maven {
      url 'https://jitpack.io'
    }
  }
}
Gradle

Step 2. Add the dependency

dependencies {
 implementation 'com.github.tejpratap46:RecyclerCalendarAndroid:LATEST_RELEASE_TAG'
}
Gradle

Here are sample calenders you can create with this library :

Week Calendar Month With Events Month With Swipe Pages
Code At: horizontal Code At: vertical Code At: viewpager
week_example month_vertical Month With Events.gif

Above sample are not the limit of this library, possiblities are endless as you can create custom view for each date as well as add custom Business Login on top of it.

Here is how you can create your own Calendar using RecyclerCalendarAndroid.
Create a RecyclerView Adapter which extends RecyclerCalendarBaseAdapter

  1. Implement following methods:
override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): RecyclerView.ViewHolder {
    val view: View = LayoutInflater.from(parent.context).inflate(R.layout.item_calendar_horizontal, parent, false)
    return MonthCalendarViewHolder(view)
}
Kotlin
  1. Create ViewHolder Class for you View which extends RecyclerView.ViewHolder:
class MonthCalendarViewHolder(itemView: View) : RecyclerView.ViewHolder(itemView) {
    val textViewDay: TextView = itemView.findViewById(R.id.textCalenderItemVerticalDay)
    val textViewDate: TextView = itemView.findViewById(R.id.textCalenderItemVerticalDate)
    val viewEvent: View = itemView.findViewById(R.id.viewCalenderItemVerticalEvent)
}
Kotlin
  1. Now just implament onBindViewHolder
override fun onBindViewHolder(
        holder: RecyclerView.ViewHolder,
        position: Int,
        calendarItem: RecyclerCalenderViewItem
	) {
    val monthViewHolder: MonthCalendarViewHolder = holder as MonthCalendarViewHolder
	// first reset view of current item as it will be reused for different dates and header.
	{
	    // Reset all you view here...
		monthViewHolder.itemView.visibility = View.VISIBLE
		monthViewHolder.itemView.setOnClickListener(null)
	}
	
	// Calendar item as 3 parts
	// 1. Header -> Where you put month name, year etc.
	// 2. Empty Space -> This is empty space to fill days before first day of month start, hide every view of ViewHolder Here
	// 3. Date -> This is a date, customise your date with event, tecket information, Available slot OR just selection etc here
	if (calendarItem.isHeader) {
	    val selectedCalendar = Calendar.getInstance(Locale.getDefault())  
		selectedCalendar.time = calendarItem.date  
  
		val month: String = CalendarUtils.getMonth(selectedCalendar.get(Calendar.MONTH)) ?: ""  
		val year = selectedCalendar[Calendar.YEAR].toLong()  
  
		monthViewHolder.textViewDay.text = year.toString()  
		monthViewHolder.textViewDate.text = month
	} else if (calendarItem.isEmpty) {
		monthViewHolder.itemView.visibility = View.GONE
		monthViewHolder.textViewDay.text = ""
		monthViewHolder.textViewDate.text = ""
	} else {  
	    val calendarDate = Calendar.getInstance(Locale.getDefault())  
	    calendarDate.time = calendarItem.date

		val day: String = CalendarUtils.getDay(calendarDate.get(Calendar.DAY_OF_WEEK)) ?: ""

		monthViewHolder.textViewDay.text = day

		val dateInt: Int =  
        (CalendarUtils.dateStringFromFormat(calendarDate.time, CalendarUtils.DB_DATE_FORMAT)  
            ?: "0").toInt()

		if (eventMap.contains(dateInt)) {
			// As an example, here im checking if this date has any event passed from constructor
	        monthViewHolder.viewEvent.visibility = View.VISIBLE
	        // Set background color from event information
			monthViewHolder.viewEvent.setBackgroundColor(eventMap.get(dateInt)!!.color)  
	    }  
 
		// Set Date to textView
	    monthViewHolder.textViewDate.text = CalendarUtils.dateStringFromFormat(calendarDate.time, CalendarUtils.DISPLAY_DATE_FORMAT) ?: ""  
  
		// Here as an example, im sending Tap data to listener
	    monthViewHolder.itemView.setOnClickListener {  
			dateSelectListener.onDateSelected(calendarItem.date, eventMap[dateInt])  
	    }  
	}
}
Kotlin

above code is direct example from VerticalRecyclerCalendarAdapter

For People who want to just use simple date picker/selection calendar, i have created SimpleRecyclerCalendarView

To use SimpleRecyclerCalendarView, just include following in your .xml

<com.tejpratapsingh.recyclercalendar.views.SimpleRecyclerCalendarView  
  android:id="@+id/calendarRecyclerView"  
  android:layout_width="match_parent"  
  android:layout_height="match_parent" />
XML

And in Your Activity, include following

val calenderView: SimpleRecyclerCalendarView = findViewById(R.id.calendarRecyclerView)  
  
val date = Date()  
date.time = System.currentTimeMillis()  
  
// Start From Date
val startCal = Calendar.getInstance()  
  
// End Date
val endCal = Calendar.getInstance()  
endCal.time = date  
endCal.add(Calendar.MONTH, 3)  
  
val configuration: SimpleRecyclerCalendarConfiguration =
            SimpleRecyclerCalendarConfiguration(
                calenderViewType = RecyclerCalendarConfiguration.CalenderViewType.VERTICAL, // calendarViewType could be VERTICAL OR HORIZONTAL
                calendarLocale = Locale.getDefault(),
                includeMonthHeader = true,
                selectionMode = SimpleRecyclerCalendarConfiguration.SelectionModeNone() // selectionMode could be one of [SelectionModeNone, SelectionModeSingle, SelectionModeMultiple, SelectionModeRange]
            )

        calenderView!!.initialise(
            startDate,
            endDate,
            configuration,
            object : SimpleRecyclerCalendarAdapter.OnDateSelected {
                override fun onDateSelected(date: Date) {
                    Toast.makeText(
                        calenderView!!.context,
                        "Date Selected: ${CalendarUtils.getGmt(date)}",
                        Toast.LENGTH_LONG
                    ).show()
                }
            })
Kotlin

To know More about SimpleRecyclerCalendarView visit SimpleRecyclerCalendarActivity

For People who want to just use infinite date picker/selection calendar, i have created InfiniteRecyclerCalendarView

To use InfiniteRecyclerCalendarView, just include following in your .xml

<com.tejpratapsingh.recyclercalendar.views.InfiniteRecyclerCalendarView  
  android:id="@+id/calendarRecyclerView"  
  android:layout_width="match_parent"  
  android:layout_height="match_parent" />
XML

And in Your Activity, include following

val calenderView: InfiniteRecyclerCalendarView = findViewById(R.id.calendarRecyclerView)  
  
val date = Date()  
date.time = System.currentTimeMillis()  
  
// Start From Date
val startCal = Calendar.getInstance()  
  
// End Date
val endCal = Calendar.getInstance()  
endCal.time = date  
endCal.add(Calendar.MONTH, 3)  
  
val configuration: InfiniteRecyclerCalendarConfiguration =
            InfiniteRecyclerCalendarConfiguration(
                calenderViewType = RecyclerCalendarConfiguration.CalenderViewType.VERTICAL, // calendarViewType could be VERTICAL OR HORIZONTAL
                calendarLocale = Locale.getDefault(),
                includeMonthHeader = true,
                selectionMode = InfiniteRecyclerCalendarConfiguration.SelectionModeNone() // selectionMode could be one of [SelectionModeNone, SelectionModeSingle, SelectionModeMultiple, SelectionModeRange]
            )

        calenderView!!.initialise(
            configuration,
            object : InfiniteRecyclerCalenderAdapter.OnDateSelected {
                override fun onDateSelected(date: Date) {
                    Toast.makeText(
                        calenderView!!.context,
                        "Date Selected: ${CalendarUtils.getGmt(date)}",
                        Toast.LENGTH_LONG
                    ).show()
                }
            })
Kotlin

GitHub