UMG Widgets

User Widgets are designed in the Widget Editor with UMG Widgets. 

User Widgets are like maps in that they trace the route between a UMG Widget and the device functions. Being able to read a User Widget will help you to understand the makeup of a UI. From the Widget Editor, you can examine:

• The UI layout and design.

• The Viewmodel functions.

• The widget bindings in View Bindings.

In the feature template, open the HUD Controller folder and double-click on the UW_HCD01 widget to learn more about how that widget was created and bound to the HUD Controller device.

Widget Layout

Widget layout is the design phase in creating a custom UI. In the Widget Editor, you can use UMG Widgets from the Palette panel to create the look, and to plan the functionality of your UI. The order in which you use UMG Widgets determines the look of the UI.

With the UW_HCD01 widget open, look in the Hierarchy panel. The Hierarchy panel shows you which UMG Widgets were used and the order in which they were added to the viewport.

All widget designs must have a root widget that acts as the screen. An Overlay widget named Root sits at the root of the design and acts as the screen. The viewport is set to Fill Screen, which causes the design to fill the Root designated area.

A Grid Panel is used to house the design of the Health and Shield bars. Grid Panels are flexible grids that organize their child widgets in rows and columns. 

You can further customize rows and columns because the Grid Panel adds options to its child widgets that control the number of rows and columns, the space rows and columns take up, the layer the widget occupies in the design, and a special movement option called Nudge. 

Nudge provides a way to move the child widget across the X and Y axes without taking up space. This means only the content inside the container is shifted, but the container maintains its position and the space it takes up in the layout. 

The Overlay widget, named ShieldBarContainer, is the first child widget of the Grid Panel. This widget sits on Row 1, Column 0 and displays across Row Span 1, Column Span 0. The ShieldBarContainer widgets display on Layer1. 

This means that all child widgets of ShieldContainer show at the front of the design because they’re on Layer 1, but sit to the right of the widgets behind it because they sit in Row 1. The shield bar spans 2 rows (0 and 1), this determines the length of the shield bar. 

Using the Nudge > Y option, you can move the ShieldBarContainer widget -25.0 Slate Units down from its default position so that it  slightly covers the Health Container behind it.

The Overlay widget named HealthBarContainer is the second child widget of the Grid Panel. This widget sits on Row 1, Column 0 and displays across Row Span 1, Column Span 0. The HealthBarContainer widgets display on Layer0. 

This means that all child widgets of HealthBarContainer show at the back of the design because they’re on Layer 0. The health bar sits in Row 0 so it displays to the left of the shield bar. The HealthBarContainer also spans Rows 0 and 1, which determines the length of the health bar. 

Below is the breakdown of UMG Widgets that make up the shield and health bars, and their purpose in the overall design.

ShieldBarContainer

The ShieldBarContainer houses all of the UMG Widgets that make up the shield bar design. The shield bar is made up of the following:

HealthBarContainer

The HealthContainer houses all the UMG Widgets that make up the health bar design. The health bar is made up of the following:

Next you’ll learn how to select a Viewmodel to update the UI materials to show the player’s current health and shield status in-game.

Viewmodel

A Viewmodel controls player information through a list of functions. The functions provide a way to control player information through the UMG Widget and device functionality. Viewmodels provide a specific way to bind UMG Widgets to Creative devices. 

Viewmodels listen to functions executing in the device using the User Widget to replace the default user interface. The viewmodel then uses the device functions to update the UI through View Bindings.

For example, the Shield and Health bar viewmodels listen to the HUD Controller's Shield and Health functions. When the HUD Controller function executes on Player Shields and Health, the Viewmodel listens to these functions and passes the information through the View Bindings to update the UI.

There are a number of different Viewmodels to choose from. In the list of Viewmodels below, notice that there are device-specific Viewmodels. These contain the functions specific to that device.

The following Viewmodels control more than one part of the UI through the device functions in the function lists. 

The Device - HUD Controller Team/Squad Player Info List is used with the UW_HCD01 widget. It uses the Controlling Player Info to ingest your information from the HUD Controller because this template is meant to be played by one player – you! 

For this UI sample, your Health and Shield are controlled through this viewmodel by listening to the functions of the HUD Controller.

Next you’ll learn how to bind Health and Shield UI materials to the HUD Controller functionality in View Bindings.

View Bindings

View Bindings maps the UMG Widget functionality to the functions of the bound device and updates the UI in the HUD. In the UW_HCD01 widget, the ShieldBar and HPBar materials are bound to the HUD Controller’s Shield and Health functions. These functions monitor your shields and health in-game and update the bar material based on how much shield and health you have.

Making the shield and health UI functional begins by selecting a UMG Widget and binding the widget properties to a specific device function. Bindings must be created in the View Bindings panel.

Adding a UMG Widget

Image widgets (ShieldBar and HPBar) are selected from the Hierarchy panel first, then from the View Bindings panel. You can click the +Add Widget button to open the list of Viewmodel functions. A function is added to the widget to control the widget’s property information. In this case, it’s the Brush function to control the ShieldBar and HPBar materials.

Adding a Device Binding

After determining which widget to bind, the device binding type is selected. There is an empty field next to the widget field. Clicking in the empty field opens a list of available device bindings. The device binding options automatically appear under the widget and device binding fields. The options determine how the widget updates based on the information it receives from the device. 

The UW_HCD01 widget uses a Set Scalar Parameter to update the Brush properties.

View Bindings

ShieldBar Brush Property	HealthBar Brush Property

Details Panel

ShieldBar Material	HealthBar Material

Setting Device Parameters

To make the material reflect the current state of the player’s shield and health, the device bindings have parameters that need to be set in order to send the device information to the UMG Widgets. 

In this sample, the Image widget and its Brush function are automatically added to the HUD Controller’s Brush parameter. This binding determines which Image widget’s Brush property to update.

Next, the Parameter Name specifies which parameter to update in the Brush material. Here, Progress is typed into the field.

Lastly, the Value for the binding is determined by the viewmodel. In the binding’s Value field, the HUDPlayerInfoListViewmodel > Controlling Player Info > Shield and Health functions are set.

The HUD Controller functionality now updates the Brush property in the Image widget through the Scalar Parameter conversion function by looking at the Progress property and passing the Health and Shield value into it. 

Progress is the value that moves the bar back and forth between the Progress Start and ProgressEnd values. This means that the Progress value is bound between 0 and 1.

ShieldBar Material Parameter Groups	HealthBar Material Parameter Groups

If you start the game with full Health and Shields, damage causes the bar to move to the left based on the Progress and Normalize Progress properties. These properties determine how much the material moves to the left when the player takes damage.

The material will move across the bar to the right when Health and Shields are restored at the same rate they deteriorate using the Progress and Normalize Progress properties.

Open other User Widgets and see if you can read them and understand the order the UMG Widgets were added to the Hierarchy, the type of viewmodel selected for the User Widget, and how the UMG Widget parameters and device functions are bound in View Bindings.

Equipped Item Viewmodel

This viewmodel can be used with the HUD Controller device to track the statistics of an equipped item using the Equipped Item Info Widget Override widget slot. All UI samples use the WID_Assault_AutoHigh_Athena_C_Ore_T03 Assault Riffle as the equipped item. 

Open the Devices > HUD Controller > Widgets folder and double-click the UW_HCD03_SelectedItem widget. From this viewmodel, you can track a number of weapon info and statistics in the UI:

1. Item Icon

2. Item Name

3. Ammo Icon

4. Ammo Count

5. Ammo Surplus

6. Is Magazine Type Weapon