How can I wait for a condition?

I finally find out...

   var waitLoading = by.css('#loading.loader-state-hidden');

   browser.wait(function() {
       return ptor.isElementPresent(waitLoading);
   }, 8000);

   expect(ptor.isElementPresent(waitLoading)).toBeTruthy();

   var openContact = by.xpath("//a[@href='#/contacts']");
   element(openContact).click();

With this protractor could wait for that element until it loading page disappears. Thanks for those who tried to help XD.

Protractor 1.7.0 has also introduced a new feature: Expected Conditions.

There are several predefined conditions to explicitly wait for. In case you want to wait for an element to become present:

var EC = protractor.ExpectedConditions;

var e = element(by.id('xyz'));
browser.wait(EC.presenceOf(e), 10000);

expect(e.isPresent()).toBeTruthy();

See also:

• Expected conditions in protractor

I had the same problem you were having for the longest time while using protractor. In my e2e test I start in a non angular app, then get into an angular portion, then get back out to a non angular portion. Made things tricky. The key is to understand promises and how they work. Here's some examples of my real world code in a functioning e2e test. Hoping this gives you an idea of how to structure your tests. Probably some bad practice in this code, please feel free to improve upon this, but I know that it works, maybe not the best way.

To get to angular I use

var ptor;
var events = require('events');
var eventEmitter = new events.EventEmitter();
var secondClick = require('./second-click');

beforeEach(function () {
    browser.driver.get('http://localhost:8080/');
},10000);

it("should start the test", function () {
    describe("starting", function () {
        it("should find the  link and start the test", function(){
            var elementToFind = by.linkText('Start'); //what element we are looking for
            browser.driver.isElementPresent(elementToFind).then(function(isPresent){
                expect(isPresent).toBe(true); //the test, kind of redundant but it helps pass or fail
                browser.driver.findElement(elementToFind).then(function(start){
                    start.click().then(function(){ //once we've found the element and its on the page click it!! :) 
                        ptor = protractor.getInstance(); //pass down protractor and the events to other files so we can emit events
                        secondClick(eventEmitter, ptor); //this is your callback to keep going on to other actions or test in another file
                    });
                });
            });
        });
    });
},60000);

While in angular this code works

 describe("type in a message ", function(){
        it("should find and type in a random message", function(){
            var elementToFind = by.css('form textarea.limited');
            browser.driver.isElementPresent(elementToFind).then(function(isPresent){
                element(elementToFind).sendKeys(randomSentence).then(function(){
                    console.log("typed in random message");
                    continueOn();
                });
            });
        });
    },15000);

After exiting angular

browser.driver.wait(function(){
   console.log("polling for a firstName to appear");
   return    browser.driver.isElementPresent(by.name('firstName')).then(function(el){
         return el === true;
       });
     }).
   then(function(){
       somefunctionToExecute()
    });

Hope that gives some guidance and helps you out!