Android Development Android UI and Layouts 2

Question 1

What class is used to implement custom drawing on a Canvas in Android?

Accepted Answer

Custom View extending View

Answer

You create a custom view by extending the View class and overriding the onDraw(Canvas) method to perform custom drawing.

Question 2

Which attribute controls the visibility of a view in Android XML?

Accepted Answer

android:visibility

Answer

The android:visibility attribute accepts VISIBLE, INVISIBLE, or GONE to control whether a view is shown or takes up space.

Question 3

What is the purpose of the include tag in Android XML layouts?

Accepted Answer

To reuse a layout file inside another layout

Answer

The <include> tag allows you to embed another layout XML file inside the current layout, promoting reusability.

Question 4

Which method is called when the size of a view changes?

Accepted Answer

onSizeChanged

Answer

onSizeChanged is called when the size of a view changes, providing the new width, height, and old values.

Question 5

What does the dp unit represent in Android?

Accepted Answer

Density-independent pixels

Answer

dp (density-independent pixels) is a virtual unit that scales based on screen density to ensure consistent physical size across devices.

Android Development Practice Test