Layouts in Android UI Design

Layout Managers (or simply layouts) are said to be extensions of the ViewGroup class. They are used to set the position of child Views within the UI we are building. We can nest the layouts, and therefore we can create arbitrarily complex UIs using a combination of layouts.

There is a number of layout classes in the Android SDK. They can be used, modified or can create your own to make the UI for your Views, Fragments and Activities. You can display your contents effectively by using the right combination of layouts.

Types of Layouts

1. ConstraintLayout

Constraint Layout is a flexible layout that allows views to be positioned using constraints instead of nesting layouts. It helps in reducing the view hierarchy and improves performance by a lot. It is the most popular and recommended layout for designing complex interfaces in modern Android applications.

2. LinearLayout

A LinearLayout aligns each of the view in a single direction either a vertical or a horizontal manner. A layout in vertical manner has a single column of views, whereas in a layout in horizontal manner, has a single row of views. It supports a weight attribute for each view that can control the relative size of each view within the available space. However, excessive nesting of Linear Layouts can lead to performance issues, so it’s best for straightforward layouts with a few elements.

3. FrameLayout

Frame Layout is a simple layout mainly used to hold a single child view, though multiple views can be stacked on top of each other. It is commonly used for overlays, fragments, and simple UI components like image views.

4. RelativeLayout

Relative layout allows views to be relative to one another or to the parent layout. This makes positioning flexible as we can position views to the left, right, top, or bottom of other views. However after Constraint Layout was introduced, the use of Relative Layout has ceased since Constraint Layout is much better as handling large UIs.

5. TableLayout

TableLayout arranges views in a grid-like format using rows and columns, similar to an HTML table. It is useful for displaying structured data, such as forms or spreadsheets. Each row consists of multiple TableRow elements, and views within rows can be assigned specific column spans.

6. GridLayout

Introduced in Android 4.0 (API level 14), the GridLayout is an advanced and more flexible alternative to TableLayout. It divides the screen into a matrix of rows and columns, allowing precise placement of elements without needing of nested layouts. It is efficient for creating grid-based UIs like image galleries or dashboards.

7. CoordinatorLayout

Coordinator Layout is an advance layout that provides motion and interactive capabilities between views. It is mostly used for implementing components like the Collapsing Toolbars, and swipe-to-dismiss behavior. It allows views to work based on user actions, such as scrolling, swipe gestures and animations.

Each of these layouts is designed to scale to suit the screen size of the host device by avoiding the use of absolute co-ordinates of the positions or predetermined pixel values. This makes the app suitable for the diverse set of Android devices.