JCEF browser flashes from corner of IDE

Brandon,

Could you please add JBCefClient.addLoadHandler before the browser component is shown, and log the loading callbacks? It looks like the problem is that the web page is loaded subsequently.

Anton,

There are no calls that hit CefLoadHandler after the browser is created for the first time. I tried some other handlers and found that CefLifeSpanHandler yields some interesting results. The first time the browser is displayed onAfterParentChanged is called twice. All subsequent times the browser is displayed it is only called once. It is called again when the balloon is closed but the first time the browser is displayed it is called twice (not including the third call when the balloon is closed).

I was also able to set some breakpoints which show the browser teleporting to the correct place:

The first time I hover over the gutter icon nothing is displayed when I step past "myLayeredPane.add(myComp);". The browser is only displayed when I step past "myComp.validate();". The second time I hover over the gutter icon I get the invalid placement of the browser at the top left of the IDE when I step past "myLayeredPane.add(myComp);" and it's only when I step past "myComp.validate();" that it goes to the correct location.

I believe the reason the webpage doesn't load under debug is because of IntelliJ's PerformanceWatcher. How can I disable this during debugging?

I would like to debug this issue further but I'm not able to get IntelliJ to stop with "Source code does not match the bytecode" whenever I try to step into the JCEF code. I'm using IntelliJ version 201.6073-EAP-CANDIDATE-SNAPSHOT and I've got the dependency:

compileOnly 'org.jetbrains.intellij.deps.jcef:jcef:3.3683.1920.g9f41a27-3'

I've checked the jars which 201.6073-EAP-CANDIDATE-SNAPSHOT is packed with and the jar for JCEF is the same so I'm not sure how the sources don't match the bytecode. Because of this, stepping through the code is difficult and not all the breakpoints I set work.

Simplified this issue down to <400 lines of Kotlin.

Source code: https://github.com/BFergerson/jcef-flash-issue

Demonstration:

This gif additionally shows the webpage is being resized once it's teleported to the correct location. I believe this is the reason for the additional flashing when the webpage is shown.

Brandon,

I've reproduced the problem with your simplified plugin, thanks. It seems like an issue with JCEF heavyweight window. Could you please file the bug on YouTrack? As a workaround I can suggest that you show JCEF via heavyweight popup window instead. I've tried and it worked that way.

Thanks again, Anton. I created issue: https://youtrack.jetbrains.com/issue/IDEA-235155

I was also able to solve this issue by using JBPopupFactory.createComponentPopupBuilder() instead of JBPopupFactory.createBalloonBuilder(). I did find two issues with this approach and it's that for some reason the popup is immediately closed the first time it's open when CefBrowser.createImmediately() is used and the second issue is once browser is displayed the second time clicking anywhere in the browser will close it.

You can see this issue with the same code at: https://github.com/BFergerson/jcef-flash-issue

First issue:

The first issue is the browser immediately closes the first time it's displayed.

Using configuration:

var preloadJcefBrowser: Boolean = true,
var useHeavyPopup: Boolean = true,
var heavyPopupCancelDelay: Int = 0, //<--- no delay
var initialUrl: String = "https://jetbrains.com"

Results in:

Second issue:

The second issue is wherever you click in the browser the second time it's displayed results in the browser being closed.

Using configuration:

var preloadJcefBrowser: Boolean = true,
var useHeavyPopup: Boolean = true,
var heavyPopupCancelDelay: Int = 500, //<--- with delay
var initialUrl: String = "https://jetbrains.com"

Results in:

I can make the first issue go away by using var preloadJcefBrowser: Boolean = false and I can make the second issue go away by using var heavyPopupCancelDelay: Int = Integer.MAX_VALUE, but then the browser can't be closed. The heavyPopupCancelDelay is used like so:

val showTime = System.currentTimeMillis()
val balloon: JBPopup = JBPopupFactory.getInstance()
    .createComponentPopupBuilder(component!!, component!!)
    .setShowBorder(false)
    .setShowShadow(false)
    .setRequestFocus(true)
    .setCancelCallback { System.currentTimeMillis() - showTime > configuration.heavyPopupCancelDelay }
    .createPopup()

My main question now is what is causing the browser to think it needs to be canceled when I click on something within the browser? Is there something I should be calling to ensure the browser has focus so it responds correctly to mouse events and doesn't think it's being closed?

Brandon,

Sorry for the delay. I've tried your latest changes, I was not able to reproduce neither the 1st nor the 2nd issue. It worked ok for me. SDK - Build #IU-201.6073.9, built on March 4, 2020

Could you please try to display the popup so that it appears from a distance to the mouse pointer, does it make a difference?

Anton,

I appreciate you following up on this. I've updated to 201.6073.9 and I've changed the example on https://github.com/BFergerson/jcef-flash-issue/tree/trigger-on-0 to display the browser when the number key '0' is typed instead of on mouse hover. The only difference I'm seeing is I'm not able to reproduce the second issue when I add a value to heavyPopupCancelDelay. If I use no delay on that variable I can still produce both issues: