selenium-webdriverjmeter

How to identify that an image in canvas html element is loaded or not

I need to capture the time taken for displaying an image in Canvas HTML element using selenium after clicking a button/key press. Can you help with an example, Thanks

Solution

  • Your question cannot be comprehensively answered because essential data is missing, here is a generic piece of code which you can either use as is or adapt to your needs:

    import org.openqa.selenium.By
import org.openqa.selenium.support.ui.ExpectedConditions
import org.openqa.selenium.support.ui.WebDriverWait

import java.time.Duration

WDS.browser.get("http://example.com")

WebDriverWait wait = new WebDriverWait(WDS.browser, Duration.ofSeconds(30))
wait.until(ExpectedConditions.presenceOfElementLocated(By.id("yourCanvasElementId")))

long before = System.currentTimeMillis()
wait.until {
    WDS.browser.executeScript("""
            var canvas = document.getElementById('yourCanvasElementId');
            return canvas.getContext && canvas.getContext('2d').getImageData(0, 0, canvas.width, canvas.height).data.length > 0;
        """)
}

long after = System.currentTimeMillis()
long delta = after - before

WDS.log.info("Time taken for image to load in canvas: ${delta} ms")

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