UI testing a tab bar controller

Question

I have built a simple tab bar with 3 tabs.

I want to run a UI test to make sure that if the user clicks a tab bar item, the correct view controller shows. How would I go about doing that? Below is the code I would start with, just don't know how to write my assertion.

func testTabBarMyProfileButton() {
    let tabBarsQuery = XCUIApplication().tabBars
    tabBarsQuery.buttons["My Profile"].tap()
}

func testTabBarGraphsButton() {
    let tabBarsQuery = XCUIApplication().tabBars
    tabBarsQuery.buttons["Graphs"].tap()
}

func testTabBarAboutButton() {
    let tabBarsQuery = XCUIApplication().tabBars
    tabBarsQuery.buttons["About"].tap()
}

Rosenberg

Answer 1

If you have different controls in each view controller shown on each tab bar, you can make assertions if they exist or not (what is expected). For example if the first tab bar has UILabel named "First name" you can assert if it exists by writing

Let theLabel = app.staticTexts["myValue"]
XCTAssert(theLabel.exists).to(beTrue)

And on the other screens do the same thing for the different controls.

Alcmene

Answer 2

You can access the tabbar button by its position:

app.tabBars.buttons.element(boundBy: 2).tap()

Goldner

This helped me. One additional info: the tabBars.buttons.element start from index 0. So the first tab bar item is 0, second one is 1 etc. – Pisgah

Answer 3

If anyone finds this looking to UI test the contents of another app, I just found a solution..

The tab bar item is a lazy variable and needs to be touched before you can reference a tab bar button by value. Add this line:

tabBarItem.accessibilityIdentifier = "my-snazzy-identifier"

to the viewDidLoad method and you should be able to do this in your UI tests:

app.tabBars.buttons["Button Title"].tap()

Afterbirth

Answer 4

You can test the title of the navigation bar.

XCTAssert(app.navigationBars["Graphs"].exists)

See my GitHub repo for a more detailed UI Testing example.

Ninetta

I wasn't planning on using a navigation bar. Is there another way? – Rosenberg

You will have to assert something unique in each screen. This can be anything from a button, text label, or UI control. – Ninetta