acivity_main.xml - batooldshilleh/TrainingTasks GitHub Wiki

Introduction:

This XML file defines the layout for an Android application's main activity.

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What can we do within this file?

  1. LinearLayout:

    • This is the root layout container, which arranges its children linearly either vertically or horizontally.
    • Attributes:
      • xmlns:android: Defines the XML namespace for Android attributes.
      • xmlns:app: Defines the XML namespace for app-specific attributes.
      • xmlns:tools: Defines the XML namespace for design-time attributes.
      • android:layout_width: Specifies the width of the layout to match its parent.
      • android:layout_height: Specifies the height of the layout to match its parent.
      • android:orientation: Specifies the orientation of child views, in this case, vertical.
      • android:layout_margin: Specifies the margins around the layout.

  2. EditText (et_a and et_b):

    • Input fields where users can enter values for 'a' and 'b'.
    • Attributes:
      • android:id: Unique identifier for referencing in code.
      • android:layout_width: Specifies the width to match its parent.
      • android:layout_height: Specifies the height to wrap its content.
      • android:hint: Placeholder text shown when the field is empty.
      • android:minHeight: Specifies the minimum height of the EditText.
      • tools:ignore: Ignored tools-specific attributes.
      • tools:layout_editor_absoluteX: Specifies the X-coordinate for layout in the editor.
      • android:autofillHints: Autofill hints for the EditText.

  3. LinearLayout (Nested):

    • Another LinearLayout nested inside the root layout to hold buttons horizontally.
    • Attributes:
      • android:layout_width: Specifies the width to match its parent.
      • android:layout_height: Specifies the height to wrap its content.
      • android:orientation: Specifies the orientation of child views, in this case, horizontal.

  4. Buttons (btn_add, btn_subtraction, btn_multiplication, btn_division):

    • Buttons for performing addition, subtraction, multiplication, and division operations.
    • Attributes:
      • android:layout_width: Specifies the width to wrap its content.
      • android:layout_height: Specifies the height to wrap its content.
      • android:text: Text displayed on the button.
      • android:layout_margin: Specifies the margins around the button.
      • android:id: Unique identifier for referencing in code.

  5. TextView (result_tv):

    • Displays the result of the arithmetic operation.
    • Attributes:
      • android:layout_width: Specifies the width to match its parent.
      • android:layout_height: Specifies the height to wrap its content.
      • android:text: Text displayed in the TextView.
      • android:textSize: Size of the text.
      • android:gravity: Alignment of the text.
      • android:id: Unique identifier for referencing in code.
      • android:layout_margin: Specifies the margins around the TextView.

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