There are also exceptions:

[joxet11299]

Here we set the name of the future application, domain, project storage location and package name. Also at this stage you can enable support for C++ or Kotlin.



Second stage


At this stage, we select the platforms on which our application will work. This is done in the SDK and AVD (Android device emulator). Using the SDK manager, we can install SDK packages of different Android OS versions and API levels.



Please note



Here we set the name of the future application, domain, project storage location and package name. Also at this stage you can enable support for C++ or Kotlin.



Third stage


Here we specify and name the main activity that will be turned on when the application starts.



The fourth stage


It will take a few minutes to build the IDE interface. Once it is done, there are three main points to understand.



There are several items in the project explorer panel. When you select Android, the application files and the path to them will be displayed. So, for example, we can find the main activity of our application, which we selected instead of Main - app > java > my.app > FullAcitve.



Here you can also see the file app > res > layout > active_full.xml, which describes the functionality and contains the layout of our activity.



The third point is app > manifests > AndroidManifest.xml. This file is responsible for the main parameters of the application and its components.



First launch




The application described above performs one activity - opening in full screen mode.



A test run can be done on a suitable Android device or in an emulator.



To test on a smartphone or tablet, you need to connect them in USB debugging mode. This is done in the "Settings" of the device in the "Developer settings" section.



Launch in the emulator is performed from Android Studio in the Run > Run menu, or by pressing Shift+F10. Then select the desired device, Android version and launch orientation from the list: portrait or landscape.





Application interface development




Interfaces are created using layouts (ViewGroup), which determine the location of widgets (View) on the screen. Widgets are all sorts of buttons, form fields, etc., with which users can interact.





Interfaces are created and configured using the Layout Editor. In most cases, it creates XML files that contain information about activities.







We select our activity file app > res > layout > active_full.xml.

From the palette (Palette) we select the appropriate widgets by dragging and dropping.

Let's take a text field (PlainText) as an example.

Drag and drop other interface elements: buttons, text fields, and so on.



Logic of work and sequence of activities




So, for example, we made a text field and a "Submit" button that should do something. Its actions can be described as follows:



Open app > java > FullAcitve.

In the FullAcitve class, we add the SendMessege() method, which will launch the method when the button we need is clicked.

We register intentions in the Intent class, which will carry out the sequential launch of activities.



Basic Rules of Android Apps




The projects are in their own "sandbox", each of which operates according to Linux security rules:



The application is one of many Linux users;

Basically, each user is assigned their own unique identifier, which is responsible for access to the files of this particular project;

Each user process runs in isolation on a virtual machine;

By default, a specific user's own process is enabled.





Two application users can be assigned a canada whatsapp number database single identifier, which allows them to exchange files with each other;

To work correctly and perform design tasks, applications may send a request for access to the phone book, messages, storage, photos, and so on.



Conclusion




Developing Android apps is a long journey that requires an individual approach each time. The more you practice and explore the possibilities, the better quality apps you can offer to users. And then you can think about monetization.



Try yourself in this direction, learn the secrets of the profession, talk to experts and evaluate your abilities in developing Android applications - it's easy as pie! Just sign up for the free master class "Development of Android applications", which is held by the International Academy TOP. Hundreds of students have already made their choice, try it yourself: