WhatsApp: New Hidden Tricks and Methods that Many Users May Not Know

Even today we propose some of the hidden tricks and methods that WhatsApp allows users. Many of you may not know them all the way down.

As many well know, the most famous and most popular app in the world is definitely WhatsApp. This fantastic application has made it so that the old SMS disappear from the radar, without these being taken into account even in the promo of the various managers.

There are many functions that WhatsApp offers, but at the same time there are many that many do not know. We are in fact here today to show you some method or some trick that you may have missed in the past.

Lock the app with password or imprint from the basic settings

This is one of the most comfortable solutions if you do not want someone to enter your WhatsApp, impicciandosi your business. The comfort is also guaranteed by the fact that you do not have to resort to third-party apps, since everything is feasible through the settings of the phone itself.

All you have to do is go to the “Manage Phone” item by choosing the APP block field later. This is done, you will have all the applications of the smartphone that you can then block. Of course, choose WhatsApp, protecting with imprint and password.

This feature is available every smartphone with Android system. But beware: the menu may change depending on the brand of your smartphone.

Deleting messages after sending them

This fantastic feature was introduced a few days ago, so many users are still in the dark. The whole thing is extremely simple, since the function has been several times anticipated.

In case you send a message to a wrong person, you can delete it without the latter being able to read it. Obviously the conditions persist: You can cancel the message within and not more than 7 minutes of time and especially as long as the recipient has not already read it. In spite of this, this will notice that you have deleted it by the wording that you can see in the picture above.

Know the precise moment in which a contact accesses WhatsApp

No, we’re not talking about just checking the last access. In fact we refer to the exact moment when a person enters online. To do this there is the now known app WhatDog, which will allow us to completely trace the movements on WhatsApp of a designated person.

Through this app we can select a contact and at any time of the day, as well as having the known closed messaging app, we will be able to receive a notification at the exact moment in which it enters online.

Hidden Methods in Java

The Java language uses an object-oriented programming where processing consists of exchanging messages between objects, which are the information pulled out of Reality (object abstraction). Objects are formed by attributes that define their characteristics and in the practice of programming are identified by the variables that the object uses to store data. An object to access its memory (attributes) and then accordingly to perform operations and change its state does so through methods. The ownership of objects to incorporate both attributes and methods into them is called encapsulation, in fact it is created as a capsule, a conceptual barrier that isolates the object from the external environment (information masking). Very often the object was built by a programmer other than the one who will use it. The latter is interested to know how to interact with the object, what are the methods that makes available and how to call them. The programmer is like the mechanic who knows the details of the operation of the car while the pilot can ignore these details. This way of understanding objects induces to consider an object as a black box. Details on the structure characteristics of the object are hidden inside by guaranteeing the Information Hiding.

Interaction between Objects

In Object Oriented Programming, the interaction between objects takes place as a mechanism called Message Exchange. An object, by sending a message to another object, can ask for a method to be executed. A message consists of three parts:

  • Recipient
  • Selector
  • Argument list

The recipient is the object to which the message is addressed.

The selector indicates the method you want to activate: it must be one of the methods made available to the recipient object.

The argument list is the set of parameters that are passed to the object when you ask to activate the method.

In a language of Pseudocodifica we can write: Recipient. Selector (list of topics).

Access to attributes

Summing up what has been said, the objects have encapsulated methods and attributes within them. Messages are the interface to objects that hides and does not allow you to see how the (Encapsulation/masking) methods are implemented. The interface allows however the use of the methods in this sense also the attributes are hidden in the object. To be able to read or change the value of an attribute, you might use a method that performs the requested operation.


The term indicates the possibility of a project to take on multiple forms, as for methods that can undergo different implementations within the class hierarchy.

The automobile and motorcycle subclasses inherit the Accelera method from the means of transport. This is guaranteed by polyformism through dynamic linkage. You define dynamic because the association between the considered object and the correct method to execute is performed during run time. Programs can have dynamic and static linking. Static when it is the compiler that is concerned with creating associations between elements (through for example variables: During compilation is linked their type). Once this link is created, it can no longer be changed (the static link is possible if you know all the information at the time of compilation). In the dynamic link is not possible during the compilation know all that information necessary to the link that can be perfected only during the Run time.


Object-Programming changes the way you understand a program because during execution it corresponds to a set of class instances (objects) that evolve, interact, create new instances, and magazines. By following this definition, objects are entities that exist during the execution of a program. When the program also ends the objects no longer exist. It is said that an object is persistent if it survives the single execution, in order to be used in another session and this is accomplished by recording the object in the mass memory.