This topic offers step-by-step instructions to design a simple UI that indicates the status of the user button and the on-board LED. You need Qt Design Studio to get started. If you don't have it installed, install it using either Qt Online Installer or Qt Maintenance Tool.

The following instructions guide you through the complete design process:

1. Create a new project:
   • Open Qt Design Studio and select Create Project.

     

   • Select the Qt for MCUs tab in the New Project wizard.
   • Select 720 x 1280 as the resolution.

     

   • Name your project and select Create.

     

   You should now see the Design Mode UI with a Rectangle and Text item visible in the 2D view . On the left you should see the Navigator pane and on the right the Properties pane.

   

2. Select the Rectangle either in the Navigator pane or 2D view to change its properties in the Properties pane:
   • Change the Fill color property to black either by using the color picker or entering Hex code (#000000) manually.

     

3. Select the Text item either in the Navigator pane or 2D view to change its properties:
   • Change Text Color to white either using the color picker or entering Hex code (#ffffff) manually.
   • Change Units to px and Size to 20.
   • Change Text to LED.

     

4. Add the button rectangle:
   • Find the Rectangle component in the Components pane under the Basic components. Drag it onto the Rectangle in the Navigator pane.

     

   • Select the new rectangle in the Navigator pane to change some of its properties in the Properties pane:
     • Change its Fill color property to grey by either using the color picker or entering the Hex code (#808080) manually.
     • Size to 140 W x 70 H.

       

     • Switch to the Layout tab in the Properties pane. Anchor the rectangle to the center of its parent.

       

     • Drag the existing Text component onto the new Rectangle in the Navigator pane.

       

5. Assign a unique ID to each item:
   • Name the Text item as buttonText.

     

   • Name the inner Rectangle item as buttonRectangle.
   • Name the parent Rectangle item as backgroundRectangle.
6. Add a MouseArea:
   • Find the MouseArea component in the Components pane under the Basic components. Drag it onto the inner Rectangle in the Navigator pane.

     

   • Double-click on the mouseArea component to name it as buttonMouseArea.
   • Anchor it to span its parent, buttonRectangle.

     

7. Bind the button's color property to the pressed property of MouseArea:
   • Select buttonRectangle in the Navigation pane.
   • Select Connections from the View > Views menu.

     

   • Switch to the Rectangle tab in the Properties pane.
   • Select the settings icon to set a new binding.

     

     

   • Enter the following expression in the Binding Editor that opens up and select OK:

     buttonMouseArea.pressed ?
         UICommunicator.led1Status ? "green" : "grey" :
         UICommunicator.led1Status ? "darkgreen" : "dimgrey"

     

   Note: UICommunicator is the C++ backend that you add in the next topic.

8. Add a connection for the onClicked handler of MouseArea:
   • Select buttonMouseArea in the Navigator pane.
   • Select the Connections tab in the Connections view.

     

   • Select + to add a new connection.
   • Select the manual conditions icon in the dialog box to open the Connection Editor.

     

   • Enter the following code into the Connection Editor and select OK:

     UICommunicator.sendFromUI(
         UICommunicator.LED1State,
         !UICommunicator.led1Status)

     

9. Save and close.
   • Select File > Save All to save your change.
   • Select File > Close Project <your-project-name> to close the project.