#Java making a contact book app registration
#Java making a contact book app password

Create a check_username method in DatabaseHelper class which receives the username as argument to check if it is present in the database or not.

#Java making a contact book app password

We need to check that if this user is present in our database or not and then if there is a user present we need to authenticate that the user has entered correct password or not. Now in the Login activity class we have fields for username and password.ContentValues is a map like class that matches string key and inserts the data given into it as arguments into the table You can have the return type of this insert method as Boolean to check whether the data has been successfully inserted or not.

#Java making a contact book app registration

Create an insert method in DatabaseHelper class which will receive the arguments from Registration activity and feed it to the database using ContentValues.This method shall contain the username, mobile number, password as the arguments. Now we need the Registration activity class to call our DatabaseHelper class using an object of SQLiteHelper to send the data inserted in the placeholders to DatabaseHelper class where these will be fed to the database.Here also define the schema of the database by executing a create table query in the onCreate() method in DatabaseHelper class. SQLiteOpenHelper is used to create an object to create tables, open or manage the database.

Create a DatabaseHelper class which will be used to connect SQLite3. Once we are done with this, we have to connect our database to our application where user data will be stored.

Idea is to have objects of users in which each object shall contain username and mobile number. Create a UserData class which will contain the way in which data will be stored in our database.Intents can be used here to take the values of these placeholders and transfer it across our list of activity classes. The Login activity will require only username and password. Creating placeholders for the name, username, mobile number, password for the user input in the Registration activity.Always make sure that the main activity will regulate the flow of the application i.e., which activity will be followed next. Now go on creating as many activities you will be using in your app.The drawable folder under res (resource) directory will contain all your images, designs etc.Always remember to map the elements in the.In the activity.xml file we can design our activity screen using XML and drag & drop methods. xml files can be found in the layout folder of the res directory. Each activity can be designed using xml and the component.by creating new classes under this directory. We can create new activities for different pages of your app under com.example. This main activity class will be the first function to be executed when our application will be launched. Now after setting the proper dependencies, we can see main activity being present by default in our application.Implementation 'de.hdodenhof:circleimageview:3.0.0' Implementation ':constraint-layout:2.0.4' constraint-layout - for designing in constraint layout.cardview - for using cardview class with the viewholder class.

recyclerview - dependency for using the recycler view in our app.

appcompat - maven dependency for using various frameworks.

The following Dependencies need to be added: It contains compiledSdkVersion, buildTypes and dependencies.

adle contains scripts to automate several tasks like simply copying some file from one directory to other. Gradle is a build system commonly used in all java applications to automate building, testing and deployment.

Add all necessary dependencies for your project in the adle file.