如何在量角器中使用 browser.wait 命令？

Question

I have my test-data(element finder and element ids) in json file and parsing in my test scripts to perform the test. The issue I have here is , I put browser.sleep after each element for the respective element to occur on the DOM. but I want to replace that browser.sleep with browser.wait since browser.sleep is not the best practice. below is my code. please give your suggestions how to replace browser.sleep with wait command.

var controlData = require("../../TestData/EmailForm/e2e_Test.json");
        var controlKeys;
        var respose;
        var testData;

        function(callback){
            controlKeys=["BtnEmailChkBox","BtnUpdate","TrueEmailGetAttribute"];
            async.eachSeries(controlKeys,function(key,next){
                commands.execute(testConfig,controlData[key],function(err,res){
                    respose = res[0].data;
                    testData = controlData[key].actions[0].data;
                    expect(respose).toEqual(testData);
                    browser.sleep(5000);
                    next();
                });
            },function(err){
                callback();
            })
        },

Answer 1

You could write custom wait function as utils for you test or you could write it directly. For this purpose Protractor provide browser.wait() function.

First argument is a function predicate, you could take a look at predefined functions in ExpectedConditions namespace.

Second one is optional and define how long to wait for the condition to be true.

Third one is also optional and define the message to use if the wait times out.

browser.wait(
  ExpectedConditions.presenceOf(your_element),
  how_long_you_want_to_wait_in_ms
  optional_third_parameter_could_be_error_message
)