Mastering Android Development with Java

Consistency, intuitive navigation, responsive design, accessibility, visual hierarchy

Static layout

Complex navigation

Minimalistic design

The activity lifecycle begins with the onCreate() method.

The activity lifecycle begins with onPause() method.

The activity lifecycle begins with onStart() method.

The activity lifecycle begins with onResume() method.

onStart()

onCreate()

onPause()

onResume()

The onStart() method is used to initialize the database connection.

The onStart() method prepares the activity to become visible and interact with the user.

The onStart() method saves the activity's state before it is destroyed.

The onStart() method handles user input events directly.

Call finish() to restart the activity.

Use onPause() to save data directly.

Implement a static variable to hold state.

Override onSaveInstanceState() to save data in a Bundle.

onPause() is for partial visibility; onStop() is for complete invisibility.

onPause() is for complete invisibility; onStop() is for partial visibility.

onPause() is for background processing; onStop() is for foreground processing.

onPause() is called when the app is closed; onStop() is called when the app is opened.

The onResume() method is part of the activity lifecycle that indicates the activity is now in the foreground and ready for user interaction.

The onResume() method is responsible for saving the activity's state.

The onResume() method is used to pause the activity's execution.

The onResume() method is called when the activity is first created.

Use Fragments to manage activity transitions.

Call the finish() method to switch activities.

Override the onBackPressed() method for navigation.

Use Intents to start a new activity.

To initialize the database connection for an activity.

To set the user interface layout for an activity in Android.

To handle user input events in an activity.

To manage background services for an activity.

Implement fixed pixel sizes for all UI elements.

Use ConstraintLayout, resource qualifiers, and density-independent pixels (dp) for responsive design.

Avoid using resource qualifiers for different screen sizes.

Use LinearLayout exclusively for all layouts.