I am attempting maintenance on a system I did not write (and aren't we all?). It is written in C Sharp and JavaScript, with Telerik reports.
It has the following code included in JavaScript that runs when the user clicks a button to display a report in a separate window:
var oIframe = $("iframe id='idReportFrame' style='display:none' name='idReportFrame' src=''>");
oIframe.load(function() { parent.ViewReports(); });
oIframe.appendTo('body');
try
{
$('#idReportForm').attr('target', 'idReportFrame');
$('#idReportForm').submit();
}
catch (err) { // I did NOT write this
}
Then the load function:
function ViewReports()
{
var rptName = $("#ReportNameField").val();
if (rptName == '') { return false; }
var winOption = "fullscreen=no,height=" + $(window).height() + "left=0,directories=yes,titlebar=yes,toolbar=yes,location=yes,status=no,menubar=yes,scrollbars=no,resizable=no, top=0, width=" + $(window).width();
var win = window.open('#Url.Action("ReportView", "MyController")?pReportName=' + rptNameCode, 'Report', winOption);
win.focus();
return false;
}
When I execute this (in Chrome, at least), it does pop up the window and put the report in it. However, breakpoints in the c# code indicate that it is getting called 2 or 3 times. Breakpoints in the JavaScript and examination of the little log in the JavaScript debugging environment in Chrome show that the call to win.focus() fails once or twice before succeeding. It returns an undefined value, and then it appears that the first routine above is executed again.
I am inclined to think it some kind of timing issue, except that the window.open() call is supposed to be synchronous as far as I can tell, and I don't know why it would succeed sometimes and not others. There is a routine that gets executed on load of the window, perhaps that's somehow screwing up the return of the value from open().
I am not a JavaScript person much, as those of you that are can likely tell by this time. If there is something with the code I've put here that you can tell me is incorrect, that's great; what I'm more hopeful for is someone who can explain how the popup-report-in-frame is supposed to work. Hopefully I can do it without having to replace too much of the code I've got, as it is brittle and was not, shall we say, written with refactoring in mind.
From what I could find the window.open will return null when it fails to open. Something may be keeping the browser from opening additional windows a couple of times; maybe it is a popup blocker.
The actual loading of the url and creation of the window are done asynchronously.
https://developer.mozilla.org/en-US/docs/Web/API/Window.open
Popup blocking
In the past, evil sites abused popups a lot. A bad page could open
tons of popup windows with ads. So now most browsers try to block
popups and protect the user.
Most browsers block popups if they are called outside of
user-triggered event handlers like onclick.
For example:
// popup blocked
window.open('https://javascript.info');
// popup allowed
button.onclick = () => {
window.open('https://javascript.info');
};
Source: https://javascript.info/popup-windows
I just ran into this and it seems to be because I had a breakpoint on the line that calls window.open and was stepping through the code, in Chrome dev tools. This was extremely hit-and-miss and seemed to fail (return null, not open a window, whether one already existed or not) more times that it succeeded.
I read #Joshua's comment that the creation is done asynchronously, so I figured that forcing the code to 'stop' each time I step might be screwing things up somehow (though on a single line like var w = window.open(...) doesn't seem like this could happen).
So, I took out my breakpoint.. and everything started working perfectly!
I also took note of https://developer.mozilla.org/en-US/docs/Web/API/Window/open where they specify that if you are re-using a window variable and name (the second argumen to window.open) then a certain pattern of code is recommended. In my case, I am wanting to write HTML content to it, rather than give it a URL and let it async load the content over the network, and I may call the whole function repeatedly without regard for the user closing the window that pops up. So now I have something like this:
var win; // initialises to undefined
function openWindow() {
var head = '<html><head>...blahblah..</head>';
var content = '<h1>Amazing content<h1><p>Isn\'t it, though?</p>';
var footer = '</body></html>';
if (!win || win.closed) {
// window either never opened, or was open and has been closed.
win = window.open('about:blank', 'MyWindowName', 'width=100,height=100');
win.document.write(head + content + footer);
} else {
// window still exists from last time and has not been closed.
win.document.body.innerHTML = content;
}
}
I'm not convinced the write call should be given the full <html> header but this seems to work 100% for me.
[edit] I found that a Code Snippet on Stackoverflow has a some kind of security feature that prevents window.open, but this jsfiddle shows the code above working, with a tweak to show an incrementing counter to prove the content update is working as intended. https://jsfiddle.net/neekfenwick/h8em5kn6/3/
A bilt late but I think it's due to the window not beeing actually closed in js or maybe the memory pointer not being dereferenced.
I was having the same problem and I solved it by enclosing the call in a try finally block.
try {
if (!winRef || winRef.closed) {
winRef = window.open('', '', 'left=0,top=0,width=300,height=400,toolbar=0,scrollbars=0,status=0,dir=ltr');
} else {
winRef.focus();
}
winRef.document.open();
winRef.document.write(`
<html>
<head>
<link rel="stylesheet" href="/lib/bootstrap/dist/css/bootstrap.min.css">
</head>
<body>
${$(id).remove('.print-exclude').html()}
</body>
</html>
`);
winRef.document.close();
winRef.focus();
winRef.print();
} catch { }
finally {
if (winRef && !winRef.closed) winRef.close();
}
Related
I'm working on an app in Xamarin.Forms, and things have been going pretty steadily, until I ran into a navigation error. The thing that mystifies me about it is that I've already been successfully using the same code calls on other pages, but suddenly with this page, it isn't working.
I have designed a bit of a unique navigation flow because of the visual result that I'm trying to accomplish, using a combination of master-detail that has two tiers of navigation pages using the normal push / pop code. I was following suggestions from this article on medium.com.
The app initializes a main page called "Root Navigation" that initializes the master and detail pages.
public App()
{
InitializeComponent();
MainPage = new RootNavigation();
}
Root Navigation page:
public partial class RootNavigation : MasterDetailPage
{
private MenuPage menuPage;
private NavigationPage OuterPage;
private NavigationPage InnerPage;
public RootNavigation()
{
this.Master = this.menuPage = new MenuPage();
this.menuPage.MenuItemsListView.ItemSelected += Menu_ItemSelected;
var viewModel = new SelectEmployeeViewModel();
var page = new SelectEmployeePage(viewModel);
SetAsDetailPage(page);
}
To navigate forward in the app, I'm using a method called "set as detail page," that bridges the gap between master-detail behavior and navigation push / pop behavior.
private void SetAsDetailPage(ContentPage page)
{
NavigationPage.SetHasNavigationBar(newPage, false);
if (newPage.GetType() == typeof(JobDetailPage))
{
newPage.ToolbarItems.Add(
new ToolbarItem()
{
Text = "Back",
Command = new Command(() => BackButton_Clicked())
});
}
this.InnerPage = this.InnerPage ?? new NavigationPage();
this.InnerPage.Navigation.PushAsync(page);
this.OuterPage = this.OuterPage ?? new NavigationPage(this.InnerPage);
this.Detail = this.Detail ?? this.OuterPage;
}
Then, navigating backward calls one of two methods: "BackButton_Clicked()" or "ReturnToJobList()".
private void ReturnToJobList()
{
while (InnerPage.CurrentPage.GetType() != typeof(JobsPage))
{
var current = InnerPage.CurrentPage.ToString();
System.Diagnostics.Debug.WriteLine($"'{current}' attempting Navigation.Pop()");
InnerPage.PopAsync();
}
}
private void BackButton_Clicked()
{
this.InnerPage.PopAsync();
}
All of the pages that display read-only data have navigated without issue. When I'm done with the page, I have it raise a call to the MessagingCenter, and the root navigation receives the message and performs the desired navigation. For example, the "MenuPage_ItemSelected" event handler fires the code:
if (e.SelectedItem.ToString().ToLower() == "log out")
{
Device.InvokeOnMainThreadAsync(() =>
{
InnerPage.PopToRootAsync();
this.IsPresented = false;
});
}
This seems to be working fine, after I spent a while researching that when a secondary page calls 'pop to root' on a background thread, I have to invoke it on the main thread.
Ok, so finally to the problem page: The "update job notes" page. The page raises a call to the Messaging Center, and the Root Navigation page picks that up and executes the following code:
private async void SaveJobNotes(ContentPage sender)
{
if (sender is UpdateJobNotesPage notesPage)
{
bool result = await SaveNewJobNote(notesPage);
var message = result ? "Saved changes" : "An error occurred; changes not saved";
await DisplayAlert("Save", message, "OK");
}
ReturnToJobList();
}
Stepping through the code, it correctly executes SaveNewJobNote() and returns true. Then, it awaits displaying the alert "Saved Changes". Then, the code then gets stuck in an infinite while loop in the "ReturnToJobList()," forever printing out into the debug output [0:] 'Application.Views.UpdateJobNotesPage' attempting Navigation.Pop(). After about a million cycles I get tired of waiting and quit the debugger. I can't seem to do anything to make the page go away!
I've tried a bunch of stuff with investigating the differences between PopAsync and PopModalAsync. After checking what's on the navigation stacks for the different pages in question, everything looks exactly like what I'd expect -- there's nothing on the modal stacks for anything (because I never called PushModalAsync on anything), there's 0 on the RootNavigation stack, 1 on the OuterPage stack, and 4 on the InnerPage stack. That all makes perfect sense to me, but it still doesn't pop the Update Job Notes page. I also tried code with Navigation.RemovePage(page) with no success. The only difference there was that the debugger included printing a warning about my code and suggesting I use PopAsync() instead.
I also tried some different things with making the PopAsync() call from this.Navigation, this.Outer, this.Outer.Navigation, this.Inner, this.Inner.Navigation, all with no success.
I have already looked at a bunch of other questions on Stack Overflow including this question and this question but none of them seem to apply in this case. Any assistance would be greatly appreciated!!
I remember this was happening to me.
I forget exactly what was the cause, but I had some funky navigation going on as well. My problem was around popups and at one point, they were creating a new stack. So when I popped, I was getting unexpected results.
I would suspect you are also creating another stack somewhere, especially if you are at 0 in the debugger.
The culprit is most likely lurking around that InvokeOnMainThread().
I haven't really figured out what the problem is with the code block that I created that was supposed to call InnerNavigation.PopAsync() until the Job List page was visible. It seems like all the variables in that code block evaluate to values that I'd expect, but somehow it doesn't seem to be able to pop anything off the stack.
However, I did change my code block that handles saving Job Notes, and it does now pop the Save Job Notes page off the stack.
private async void SaveJobNotes(ContentPage sender)
{
this.InnerPage.PopAsync(); //I don't understand why this works and the
//other didn't, but it correctly pops the page
if (sender is UpdateJobNotesPage notesPage)
{
bool noteSaved = await SaveNewJobNote(notesPage);
bool progressSaved = await SaveJobProgress(notesPage);
var message = noteSaved && progressSaved ?
"Changes were save successfully" :
"An error occurred; changes not saved";
await DisplayAlert("Save", message, "OK");
}
}
In my automation project.
Browser: Firefox
I would like add a wait function without any specific time
driver.Manage().Timeouts().ImplicitlyWait(TimeSpan.FromSeconds(7));
IWebElement query1 = driver.FindElement(By.("continue"));
How can do that?
Also to verify that if another page did not load then repeat the previous function. The reason why I am doing this is because sometimes browser does not change the page. It actually stays on that same page.
Besides this is below thing possible in Selenium
Clear Cache and Cookie for last hour
Opening URL in new tab (In already opened browser rather then opening new window)
One thing that has worked consistently for me (regarding waits) is used in the conductor framework..
Here's some pseudo-code you can attempt to recreate in C#:
while (size == 0) {
size = driver.findElements(by).size();
if (attempts == MAX_ATTEMPTS) fail(String.format("Could not find %s after %d seconds",
by.toString(),
MAX_ATTEMPTS));
attempts++;
try {
Thread.sleep(1000); // sleep for 1 second.
} catch (Exception x) {
fail("Failed due to an exception during Thread.sleep!");
x.printStackTrace();
}
}
basically this loops through the size of the selector passed, and will poll each second. Another way you can do it, is just by conditions.
Some more pseudo-code:
function waitForElement(element) {
Wait.Until(ExpectedConditions.elementIsClickable(element), 10.Seconds)
}
And to your questions -
Can Selenium...
Clear Cache and Cookie for last hour
Opening URL in new tab (In already opened browser rather then opening new window)
Opening URL in new tab (In already opened browser rather then opening new window)
If you write your tests cases correctly by making them independent of one-another and not re-using the same browser over and over, this happens automatically. When Selenium opens a new window, it starts fresh with an entirely fresh profile - meaning it has "nothing" in the cache from the start.
Selenium does not (and will never) know the difference between a tab and a window. To Selenium, it's just a handle.
Source:
Alrighty, guys. If you'd like to pull your hair out, the I've got a great problem for you. This problem seems very rare, but it effects my program on a few different sites that have pages that load content twice.
For instance: http://www.yelp.com/search?find_desc=donuts&find_loc=78664&ns=1#start=20
If you visit this site, you'll notice that it loads, then reloads different data. That's because there is a parameter in the URL that says start=20, so the results should start at #20 instead of #10. No matter what that is set to, Yelp loads the first 10 results. Not sure why they do this, but this is a prime example of what absolutely breaks my program. :(
Basically, whenever my program has a page that loads, it copies the source code to a string so it can display it somewhere else. It's not really important- What is important is that the string needs to actually have the last thing that is loaded in the page. Whenever a page loads, then loads again, I am not sure how to catch it and it ruins the program by exiting the while loop, and copying the source code into the string called source.
Here is a snippit of some code that I reproduced the problem with. When I attempt to use this in a new program, it will copy the source code for the first pages' results instead of what it is changed to.
GetSite = "http://www.yelp.com/search?find_desc=donuts&find_loc=78664&ns=1#start=20";
webBrowser9.Navigate(GetSite);
while (webBrowser9.ReadyState != WebBrowserReadyState.Complete)
{
p++;
if (p == 1000000)
{
MessageBox.Show("Timeout error. Click OK to skip." + Environment.NewLine + "This could crash the program, but maybe not.");
label15.Text = "Error Code: Timeout";
break;
}
Application.DoEvents();
}
mshtml.HTMLDocument objHtmlDoc = (mshtml.HTMLDocument)webBrowser9.Document.DomDocument;
Source = objHtmlDoc.documentElement.innerHTML;
Why do you wait in while loop for the browser to finish loading data?
Use DocumentCompleted event and you can remember the document's URL from there.
I am using Selenium 2.25 WebDriver
I'm having a issue with finding the elements on the page and some times my test cases able to find element and sometime the page is does not load and its due to page load and if i add this below line and it seems like working:
driver.Manage().Timeouts().SetPageLoadTimeout(TimeSpan.FromSeconds(2));
my question is, i dont want to have my code scatter with the above line of code, is there a way to make it centerlize in one place?
Any help would be greatly appreciated, thanks!
If you set the timeout once, it's set for the lifetime of the driver instance. You don't need to keep resetting it. You can set this immediately after creating the driver.
IWebDriver driver = new FirefoxDriver();
driver.Manage().Timeouts.SetPageLoadTimeout(TimeSpan.FromSeconds(2));
The only caveat for using this timeout is that not every browser may support it completely (IE does for sure, Firefox does too I think, but I don't think Chrome does).
You can try a workaround like this:
Observe the element that loads last in your page and find its id (or any other identifier). Then do something like this:
while (true)
{
try
{
IWebElement element = driver.FindElement(By.Id(...));
if (element.Displayed)
{
break;
}
}
catch (Exception)
{
continue;
}
}
This will keep looping till the element which is loaded last is displayed and breaks thereupon. The element not found exception is caught and loop is put into continuation till the element is not displayed.
I have a web application that, under some conditions, pop up JavaScript alert()s that I need to react to in a WatiN test. Google pointed me at Handling alerts in WATIN from way back in 2007 that seemed promising, and I adapted the example code in that post into the following (anonymized):
private void MyAssert(IE browser, WatinHelper helper)
{
AlertDialogHandler alertDialogHandler = new AlertDialogHandler();
using (new UseDialogOnce(browser.DialogWatcher, alertDialogHandler))
{
// DoWrong() causes a JavaScript alert(); false means use nowait.
DoWrong(helper, false);
alertDialogHandler.WaitUntilExists(10 /*seconds*/);
if (!alertDialogHandler.Exists())
{
Assert.Fail("No JavaScript alert when it should have been there");
}
alertDialogHandler.OKButton.Click();
}
SecondAssert(browser);
}
However, while the alert is displayed virtually instantaneously (as it is supposed to) when DoWrong() is called, the call to alertDialogHandler.WaitUntilExists() eventually fails with a WatiNException: Dialog not available within 10 seconds... The only problem was that I could see that the dialog most definitely was up on the screen.
I'm probably missing something simple; can someone point me in the right direction please?
I have also tried the following two variants, and some variations of them, with no luck; I keep getting the same error.
AlertDialogHandler alertDialogHandler = new AlertDialogHandler();
DoWrong(helper, false);
System.Diagnostics.Stopwatch stopwatch = new System.Diagnostics.Stopwatch();
stopwatch.Start();
do
{
}
while (!alertDialogHandler.Exists() && stopwatch.Elapsed.TotalMilliseconds < 3000);
Assert.IsTrue(alertDialogHandler.Exists(), "No JavaScript alert when it should have been there");
alertDialogHandler.OKButton.Click();
SecondAssert(browser);
and
AlertDialogHandler alertDialogHandler = new AlertDialogHandler();
browser.DialogWatcher.Add(alertDialogHandler);
DoWrong(helper, false);
alertDialogHandler.WaitUntilExists();
alertDialogHandler.OKButton.Click();
browser.WaitForComplete();
Assert.IsFalse(alertDialogHandler.Exists());
SecondAssert(browser);
Yes, I know that code is getting a bit ugly, but right now I'm mostly trying to get it to work at all. If it sits for a few seconds cooking the CPU at 100% utilization because of the tight loop in my second attempt, but only does what I need it to (plain and simple, dismiss that alert()), it's OK.
This is an issue with WatiN and IE8 and the way IE8 changed the way it creates popups. The issue is fixed in the current code available at the Sourceforge SVN repository for the project. Get it, compile it and your problem is solved.
A new release of WatiN will be available before the end of this year.
HTH,
Jeroen