Kotlin Coroutine Confidence: try-catch not working (pg 37)

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Oops! Thank you for spotting this problem. I can see the same issue when I run the code myself. Something must have gone wrong when I was testing this part of the code.

I think the code catches the exception, but fails to update the window to display the error message text, so there’s no sign that an error was caught.

Here’s a modified version that should work better. I’ve changed the catch block to put the error message in a new dialog box of its own. Acknowledging the error will also close the app, so it doesn’t hang forever.

suspend fun main(): Unit = withContext(Dispatchers.Main) {
  val window = createImageViewerWindow()

  try {
    loadImage(window)
  } catch (error: Throwable) {
    JOptionPane.showMessageDialog(window, "Sorry, something went wrong")
    window.dispose()
  }
}

Thank you again for spotting my mistake! Please can you confirm that you do see an error message when using a bad URL or API key with this new version of the code? I’ll be sure to fix this code in the next Beta update.