Adding events on week view calendar by tapping in empty view. Get the week view calendar from https://github.com/alamkanak/Android-Week-View

activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity"
    android:background="#fff">

    <com.alamkanak.weekview.WeekView
        android:id="@+id/weekView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:eventTextColor="@android:color/white"
        app:textSize="12sp"
        app:hourHeight="60dp"
        app:headerColumnPadding="8dp"
        app:headerColumnTextColor="#8f000000"
        app:headerRowPadding="12dp"
        app:columnGap="8dp"
        app:noOfVisibleDays="3"
        app:headerRowBackgroundColor="#ffefefef"
        app:dayBackgroundColor="#05000000"
        app:todayBackgroundColor="#1848adff"
        app:headerColumnBackground="#ffffffff"/>

</RelativeLayout>

MainActivity.java

package com.alamkanak.weekview.sample;
import android.app.Activity;
import android.os.Bundle;
import com.alamkanak.weekview.WeekView;
import com.alamkanak.weekview.WeekViewEvent;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.List;


/**
 * Created by Raquib-ul-Alam Kanak on 7/21/2014.
 * Website: http://alamkanak.github.io
 */
public class MainActivity extends Activity implements WeekView.MonthChangeListener, WeekView.EmptyViewClickListener {

    private WeekView mWeekView;
    private ArrayList<WeekViewEvent> mNewEvents;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        // Get a reference for the week view in the layout.
        mWeekView = (WeekView) findViewById(R.id.weekView);

        // The week view has infinite scrolling horizontally. We have to provide the events of a
        // month every time the month changes on the week view.
        mWeekView.setMonthChangeListener(this);
        
        // Set up empty view click listener.
        mWeekView.setEmptyViewClickListener(this);
        
        // Initially, there will be no events on the week view because the user has not tapped on 
        // it yet.
        mNewEvents = new ArrayList<WeekViewEvent>();
    }

    @Override
    public List<WeekViewEvent> onMonthChange(int newYear, int newMonth) {
        // Populate the week view with the events that was added by tapping on empty view.
        List<WeekViewEvent> events = new ArrayList<WeekViewEvent>();
        ArrayList<WeekViewEvent> newEvents = getNewEvents(newYear, newMonth);
        events.addAll(newEvents);        
        return events;
    }

    /**
     * Get events that were added by tapping on empty view. 
     * @param year The year currently visible on the week view.
     * @param month The month currently visible on the week view.
     * @return The events of the given year and month.
     */
    private ArrayList<WeekViewEvent> getNewEvents(int year, int month) {
        
        // Get the starting point and ending point of the given month. We need this to find the 
        // events of the given month.
        Calendar startOfMonth = Calendar.getInstance();
        startOfMonth.set(Calendar.YEAR, year);
        startOfMonth.set(Calendar.MONTH, month - 1);
        startOfMonth.set(Calendar.DAY_OF_MONTH, 1);
        startOfMonth.set(Calendar.HOUR_OF_DAY, 0);
        startOfMonth.set(Calendar.MINUTE, 0);
        startOfMonth.set(Calendar.SECOND, 0);
        startOfMonth.set(Calendar.MILLISECOND, 0);
        Calendar endOfMonth = (Calendar) startOfMonth.clone();
        endOfMonth.set(Calendar.DAY_OF_MONTH, endOfMonth.getMaximum(Calendar.DAY_OF_MONTH));
        endOfMonth.set(Calendar.HOUR_OF_DAY, 23);
        endOfMonth.set(Calendar.MINUTE, 59);
        endOfMonth.set(Calendar.SECOND, 59);
        
        // Find the events that were added by tapping on empty view and that occurs in the given 
        // time frame.
        ArrayList<WeekViewEvent> events = new ArrayList<WeekViewEvent>();
        for (WeekViewEvent event : mNewEvents) {
            if (event.getEndTime().getTimeInMillis() > startOfMonth.getTimeInMillis() &&
                    event.getStartTime().getTimeInMillis() < endOfMonth.getTimeInMillis()) {
                events.add(event);
            }
        }
        return events;
    }

    @Override
    public void onEmptyViewClicked(Calendar time) {
        // Set the new event with duration one hour.
        Calendar endTime = (Calendar) time.clone();
        endTime.add(Calendar.HOUR, 1);
        
        // Create a new event.
        WeekViewEvent event = new WeekViewEvent(20, "New event", time, endTime);
        mNewEvents.add(event);
        
        // Refresh the week view. onMonthChange will be called again.
        mWeekView.notifyDatasetChanged();
    }
}

It works properly and it's fantastic. Can someone tell me how to put (or convert) the parameters of the event just created? I need to get the date of new event, the starttime and end time in format yyyy-mm-dd and hour in hh:mm but i don't be able to retrieve this data. Your help would be apreciated. Thanks in advance

I know its almost a year later. But to format Calendar etc. Use something like SimpleDateFormat format1 = new SimpleDateFormat("yyyy-MM-dd");
String date1 = format1.format(date);
That should get you started. But you might not want to pass it into a String for what your needing.

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