Column and Row layouts in Android Kotlin - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ ui_behavior

intermediate

What is the output of this Column layout code?

Consider this Kotlin Compose code snippet. What will the screen show?

Android Kotlin

Column {
  Text("Hello")
  Text("World")
}

A Empty screen with no text

B Two texts side by side horizontally: Hello left, World right

C Only one text: HelloWorld combined

D Two texts stacked vertically: Hello on top, World below

💡 Hint

Column stacks children vertically, like a list going down.

Column arranges its children vertically. So Text("Hello") is above Text("World").

❓ ui_behavior

intermediate

What happens if you use Row with these Texts?

Look at this Kotlin Compose code. What is the visual result?

Android Kotlin

Row {
  Text("Left")
  Text("Right")
}

A Texts overlap on top of each other

B Texts appear side by side horizontally: Left then Right

C Texts appear stacked vertically: Left above Right

D Only one text: LeftRight combined

💡 Hint

Row arranges children horizontally, like a row of items.

Row places its children next to each other horizontally, so Left is on the left and Right is on the right.

❓ lifecycle

advanced

What happens if you nest a Row inside a Column?

Given this code, how will the texts be arranged on screen?

Android Kotlin

Column {
  Text("Top")
  Row {
    Text("Left")
    Text("Right")
  }
  Text("Bottom")
}

A Top text on top, then Left and Right side by side, then Bottom text below

B All texts stacked vertically: Top, Left, Right, Bottom

C All texts side by side horizontally: Top, Left, Right, Bottom

D Only Top and Bottom texts visible, Left and Right hidden

💡 Hint

Column stacks vertically; Row inside it stacks horizontally.

The Column stacks Top, then the Row with Left and Right horizontally, then Bottom below.

📝 Syntax

advanced

Which option causes a syntax error in this Column layout?

Identify the option that will NOT compile in Kotlin Compose.

Android Kotlin

Column {
  Text("One")
  Text("Two")
}

A

Column {
  Text("One")
  Text("Two"
}

B

Column {
  Text("One")
  Text("Two")
}

C

Column {
  Text("One")
  Text("Two")
  Text("Three")
}

D

Column {
  Text(text = "One")
  Text(text = "Two")
}

💡 Hint

Look for missing or extra parentheses or braces.

Option A is missing a closing parenthesis for Text("Two"), causing a syntax error.

🧠 Conceptual

expert

What is the effect of using Modifier.weight(1f) in a Row?

In this Row, what does Modifier.weight(1f) do to the Text composables?

Android Kotlin

Row {
  Text("A", Modifier.weight(1f))
  Text("B", Modifier.weight(2f))
}

A Weights have no effect inside a Row

B Text A and B have equal width regardless of weight

C Text B takes twice the horizontal space of Text A

D Text A takes twice the horizontal space of Text B

💡 Hint

Weight controls how much space each child fills proportionally.

Weight divides available space proportionally. Text B with weight 2f gets twice the width of Text A with weight 1f.

Practice

1. Which layout arranges its child views vertically in Android Kotlin?

easy

A. Row

B. Column

C. Grid

D. FrameLayout

Solution

1. Step 1: Understand layout orientation

   Column arranges children vertically, stacking them top to bottom.

2. Step 2: Compare with other layouts

   Row arranges children horizontally, Grid arranges in a grid, FrameLayout stacks overlapping.

3. Final Answer:

   Column -> Option B

4. Quick Check:

   Vertical arrangement = Column [OK]

Hint: Vertical means top to bottom, so use Column [OK]

Common Mistakes:

• Confusing Row with Column
• Thinking Grid arranges vertically only
• Mixing FrameLayout stacking with vertical layout

2. Which of the following is the correct Kotlin syntax to create a Row layout with two Text views inside?

easy

A. Row(
Text("Hello"),
Text("World")
)

B. Column {
Text("Hello")
Text("World")
}

C. Row {
Text("Hello")
Text("World")
}

D. Row {
TextView("Hello")
TextView("World")
}

Solution

1. Step 1: Identify correct Row syntax

   Row uses curly braces with child composables inside, separated by lines.

2. Step 2: Check child components

   Text is the correct composable for text display, TextView is Android View, not Compose.

3. Final Answer:

   Row { Text("Hello") Text("World") } -> Option C

4. Quick Check:

   Row uses braces and Text composables [OK]

Hint: Use braces {} for layouts and Text composable for text [OK]

Common Mistakes:

• Using parentheses instead of braces for Row
• Using Column instead of Row
• Using TextView instead of Text composable

3. What will be the visual arrangement of the following code?

Column {
  Text("A")
  Row {
    Text("B")
    Text("C")
  }
  Text("D")
}

medium

A. A at top, B and C side by side in middle, D at bottom vertically

B. A, B, C, D all side by side horizontally

C. A, B, C stacked vertically, D missing

D. Only A and D visible, B and C hidden

Solution

1. Step 1: Analyze outer Column layout

   Column stacks children vertically: Text("A"), then Row, then Text("D").

2. Step 2: Analyze inner Row layout

   Row arranges Text("B") and Text("C") horizontally side by side.

3. Final Answer:

   A at top, B and C side by side in middle, D at bottom vertically -> Option A

4. Quick Check:

   Column vertical + Row horizontal = mixed layout [OK]

Hint: Column stacks vertically, Row stacks horizontally inside [OK]

Common Mistakes:

• Thinking Row inside Column stacks vertically
• Ignoring inner Row layout
• Assuming all texts are horizontal

4. Identify the error in this Kotlin Compose code snippet:

Row {
  Text("Hello")
  Text("World")
  Column(
    Text("Nested")
  )
}

medium

A. Missing comma between Text("Hello") and Text("World")

B. Text composable cannot be inside Column

C. Row cannot contain Column as child

D. Column should use braces {} instead of parentheses ()

Solution

1. Step 1: Check Column syntax

   Column uses curly braces {} to enclose children, not parentheses ().

2. Step 2: Verify child composables

   Text can be inside Column; Row can contain Column; commas are not needed between children.

3. Final Answer:

   Column should use braces {} instead of parentheses () -> Option D

4. Quick Check:

   Layouts use braces {} for children [OK]

Hint: Use {} for layout children, not () [OK]

Common Mistakes:

• Using () instead of {} for layouts
• Thinking commas are required between children
• Believing nested layouts are not allowed

5. You want to create a UI where three buttons are arranged horizontally, but the middle button should be twice as wide as the others. Which layout and modifier approach is best in Kotlin Compose?

hard

A. Use Row with weights: Button1 weight=1, Button2 weight=2, Button3 weight=1

B. Use Column with padding on middle button

C. Use Row with fixed width buttons and margin on middle button

D. Use Column with weight modifiers on buttons

Solution

1. Step 1: Choose horizontal layout

   Row arranges children horizontally, perfect for side-by-side buttons.

2. Step 2: Use weight modifier for sizing

   Assign weights to buttons to control relative widths; middle button weight=2 makes it twice as wide.

3. Final Answer:

   Use Row with weights: Button1 weight=1, Button2 weight=2, Button3 weight=1 -> Option A

4. Quick Check:

   Row + weights control horizontal size [OK]

Hint: Use Row and weight modifiers for proportional widths [OK]

Common Mistakes:

• Using Column for horizontal arrangement
• Using fixed widths instead of weights
• Applying padding instead of weight for size