Drag and drop is not happening in Cypress.io test

问题

I am trying to drag an element and then drop it into a drop zone area, but the test is not performing the drag and drop action in Cypress.io. It would be really helpful if someone could advise about the potential issue here. There are no errors throwing, but still, the drag and drop is not happening here.

describe('Verify the drag and drop test', function() {

  it.only('Check whether the drag and drop of an item is working fine', function() {

  cy.visit('http://www.seleniumeasy.com/test/drag-and-drop-demo.html')  

    const MyDataTransfer = function () {};
    const dt = new MyDataTransfer ();
    dt.types = [];

    // cy.wait(3000);

    cy.get('#todrag span')
      .contains('Draggable 1')
      .trigger("draggable", {dataTransfer: dt});

    cy.get("#todrag span")
      .contains('Draggable 1')
      .trigger('mousedown', { which: 1, pageX: 600, pageY: 600 })
      .trigger('mousemove', { which: 1, clientX: 330, clientY: 35 });

    cy.wait(3000);

    cy.get('#mydropzone')
      .trigger("dropzone", {dataTransfer: dt});                     
  });   
});

回答1:

A few changes should achieve what you are looking for. Here's a breakdown of steps taken to solve this question...

First off, instead of stubbing out MyDataTransfer, just construct a new DataTransfer object, which comes packed with the necessary properties and methods needed for drag events:

const dataTransfer = new DataTransfer;

Next, it's best to trigger native drop and drag events, as opposed to draggable and dropzone. Selenium Easy is listening for dragstart, dragend, and drop (you can see this inside of their drag-and-drop-demo.js source file). Put these inside of a helper function, to be called later inside the test:

function dndIt() {
  cy.get('#todrag span:first-of-type')
    .trigger('dragstart', { dataTransfer });

  cy.get('#mydropzone')
    .trigger('drop', { dataTransfer });

  cy.get('#todrag span:first-of-type')
    .trigger('dragend');               // <-- seleniumeasy listens for this...
}                                      // otherwise, draggables are copied.

A beforeEach block is helpful for setting the viewport and visiting the application:

beforeEach(function() {
  cy.viewport(1000, 600);
  cy.visit('https://www.seleniumeasy.com/test/drag-and-drop-demo.html');
});

And finally, the test block calls the helper function, and asserts that the item was dragged and dropped:

it('Check whether the drag and drop of an item is working fine', function() {
  dndIt();

  cy.get('#droppedlist')
    .should(($el) => {
      expect($el.children()).to.have.lengthOf(1)
    });
});

Here's the solution in its entirety:

describe('Verify the drag and drop test', function() {
  const dataTransfer = new DataTransfer;

  function dndIt() {
    cy.get('#todrag span:first-of-type')
      .trigger('dragstart', { dataTransfer });

    cy.get('#mydropzone')
      .trigger('drop', { dataTransfer });

    cy.get('#todrag span:first-of-type')
      .trigger('dragend');               // <-- seleniumeasy listens for this...
  }                                      // if left out, draggables are copied.

  beforeEach(function() {
    cy.viewport(1000, 600);
    cy.visit('https://www.seleniumeasy.com/test/drag-and-drop-demo.html');
  });

  it('Check whether the drag and drop of an item is working fine', function() {
    dndIt();

    cy.get('#droppedlist')
      .should(($el) => {
        expect($el.children()).to.have.lengthOf(1)
      });
  });
});

The drag_n_drop_spec.js provided in the cypress-example-recipes repo was a helpful resource.

来源：https://stackoverflow.com/questions/51889918/drag-and-drop-is-not-happening-in-cypress-io-test

标签

javascript

drag-and-drop

cypress