Measure Fluidity and Foreground Memory

• App launch
• Transitions between foreground and background
• Memory-intensive operations

• UI interactions
• Video playback quality

• Complete the prerequisites section
• Record a UI interaction with your app
• Generate a test scenario script
• Create a test scenario
• Measure the fluidity of your app

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Prerequisites

1. Download, build, and install the Vega video app. Follow the instructions in the Vega video app documentation. After you download the app, check the samples directory for sample test scenarios. Follow the guidance according to your app specific requirements.
2. Install Appium Server and Appium Vega Driver. Follow steps 1-4 in Install Appium for Vega integration. You need Appium, an automation tool, to write scripts and measure the fluidity of your app.
3. Download Appium Inspector.

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Record a UI interaction

1. Follow steps 1-6 in Inspect Your App in Appium Inspector.
2. Select the Start Recording icon to start the UI interactions with your app.
3. Select the Tap/Swipe by Coordinate ([+]) icon on the left panel of the screen.

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Generate a test scenario script

• Foreground memory monitoring
• UI fluidity assessment
• Video fluidity evaluation

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Generate the script

1. In VS Code, open the command palette. Mac: Shift+Command ⌘+P Linux: Shift+Ctrl+P
2. Enter Vega: Generate test scenario template.
3. Create a filename for the test scenario script. After you generate the template, VS Code displays a message. Python is the language for this template. Inside the template, you can find TestRunner class, which contains two members:
   • prep (in blue box)
   • run (in red box)
   During the test, each member performs a function:
   • prep - Performs all necessary preparations before running the actual test scenario. For example, to play video, define the navigation and playback code inside this member function. An example of the prep is in Create a test scenario.
   • run - Defines the UI interactions and actions for your test case. For example, to measure video playback fluidity over time, call the sleep function to wait for that duration.

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Create a test scenario

• Record D-pad key events
• Record video streaming

The Amazon Fire TV Stick includes a remote control with a black circular directional pad (D-pad).In this section, you create a test scenario to switch the UI component in your app by simulating the D-pad input. You write code that replicates a remote control’s D-pad functionality. By pressing the D-pad, your app users can cycle through options or move a selection in a specific direction they choose. Your code should enable the same navigation experience within your app’s UI.To simulate D-pad input, follow these steps:

1. In the Appium Inspector, go to the Commands tab and select Execute Script > executeScript. This action sends the UI interaction command from the Appium Inspector to the Vega device.
2. To simulate pressing the D-pad keys on a remote control, use the executeScript method with the following arguments:
   • executeScriptCommand - Use jsonrpc: injectInputKeyEvent to send key events representing D-pad key presses.
   • jsonArgument - A JSON object with the following properties:
     • inputKeyEvent (string) - The key event value for the D-pad direction. To find the codes for D-pad, see the D-pad navigation section in Appium commands.
     • holdDuration (number) - The duration in milliseconds to simulate holding the D-pad key pressed. Use 0 for a single press.
   For example, to send a D-pad “Down” command with 0 seconds hold duration, add this code to jsonArgument:
   [[{"inputKeyEvent": "108", "holdDuration": 0}]]
   
   Example:
3. Generate a test scenario template and copy the UI interactions recorded from the Appium Inspector to the template. Follow the steps in Generate a test scenario script.
4. Go back to Appium Inspector.
5. Select the Recorder tab to see the recorded code.

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Test scenario goal

• Launch an app in ready-state without UI interactions.
• Measure the UI fluidity of an app while sending a D-pad key to move the UI focus on the page.

You don’t need to define anything in the prep member function when copying code from the Appium Inspector’s Recorder box. The Recorder captures your interactions with the app’s UI during the recording session. Paste the code representing the recorded UI interactions into the run member function. The code executes the same UI interactions on the app during test execution.In the following image, the test simulates repeated user input by sending the same D-pad key press event five times in a loop.

In this section, you:

1. Create a test scenario to stream video from the Vega video app.
2. Measure video playback fluidity and time-to-first-frame video fluidity (TTFVF).
3. Use Appium Inspector to intereact with the Vega video app and record your interactions.
4. Copy the recorded interactions into your test scenario template from Generate a test scenario script. To simulate playing video from the Vega video app
   1. In the Appium Inspector, select the Tap/Swipe by Coordinate ([+]) icon. The cursor changes to a crosshair.
   2. Select the UI element of your app where you want to start the UI interaction.
   3. Locate the thumbnail for the test video you want to stream.
   4. Tap the test video thumbnail to open the video player screen.
   5. Tap the play button to start streaming the video.
   6. Go back to Appium Inspector.
   7. Click the Recorder tab to see recorded code.

In this test scenario, the goal is to:

• Launch the Vega video app.
• Start the video playback by clicking the video thumbnail and the play button. The app enters a ready-state mode to measure video playback fluidity.
• Measure the video playback fluidity for the duration that you want.

Define two key functions in your app:

• prep is an acronym to preparation. Therefore, it should contain actions to set up the test for an iteration.
• run member function should contain actions related to actual KPI measurements for a test iteration.

In the image:

• The prep (in blue box) member function code navigates to the Vega video app carousel and starts the video.
• The run (in red box) member function measures video streaming fluidity.

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Measure the fluidity of your app

1. Open the command palette in VS Code. Mac: Shift+Command ⌘+P Linux: Shift+Ctrl+P
2. Enter Vega: Launch App KPI Visualizer.
3. Select a use case from the command palette.
4. Make sure the checkbox for the Record CPU Profiler is empty, then press OK.
5. Select Yes in the Custom Test Scenario dialog box.
6. Pass the test scenario you generated in Generate a test scenario script.
7. Run the test.

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Related topics

• App Performance Best Practices
• Measure App KPIs
• Identify UI Rendering Issues
• Detect Overdraw
• Investigate Component Re-rendering Issues