Is there a way to wait for all network requests to finish when testing UI in XCode?
I have an app that sends HTTP requests to get some data from a server, and, in UI tests, I'd like to wait for this data to be retrieved before continuing. Currently I'm using sleep(1) but this approach doesn't seem reliable.
Your best bet is to wait for some UI element to appear or disappear. Think of it this way:
The framework acts like a user. It doesn't care what code is running under the hood. The only thing that matters is what is visible on the screen.
That said, here is how you can wait for a label titled "Go!" to appear in your UI Tests.
let app = XCUIApplication()
let goLabel = self.app.staticTexts["Go!"]
XCTAssertFalse(goLabel.exists)
let exists = NSPredicate(format: "exists == true")
expectationForPredicate(exists, evaluatedWithObject: goLabel, handler: nil)
app.buttons["Ready, set..."].tap()
waitForExpectationsWithTimeout(5, handler: nil)
XCTAssert(goLabel.exists)
You could also extract that into a helper method. If you use some Swift compiler magic you can even get the failure message to occur on the line that called the method.
private fund waitForElementToAppear(element: XCUIElement, file: String = #file, line: UInt = #line) {
let existsPredicate = NSPredicate(format: "exists == true")
expectationForPredicate(existsPredicate, evaluatedWithObject: element, handler: nil)
waitForExpectationsWithTimeout(5) { (error) -> Void in
if (error != nil) {
let message = "Failed to find \(element) after 5 seconds."
self.recordFailureWithDescription(message, inFile: file, atLine: line, expected: true)
}
}
}
You can set up your methods with delegates or completion blocks, and in your test cases use a XCTestExpectation which you can fulfill when the data has been returned.
