event_target_test.html - Android社区 - https://www.androidos.net.cn/

<!DOCTYPE html>
<html>
<head>
<!-- TODO(arv): Check in Closue unit tests and make this run as part of the
     tests -->
<script src="http://closure-library.googlecode.com/svn/trunk/closure/goog/base.js"></script>
<script src="../cr.js"></script>
<script src="event_target.js"></script>
<script>

goog.require('goog.testing.jsunit');

</script>
</head>
<body>
<script>

const EventTarget = cr.EventTarget;
const Event = cr.Event;

function testFunctionListener() {
  var fi = 0;
  function f(e) {
    fi++;
  }

  var gi = 0;
  function g(e) {
    gi++;
  }

  var et = new EventTarget;
  et.addEventListener('f', f);
  et.addEventListener('g', g);

  // Adding again should not cause it to be called twice
  et.addEventListener('f', f);
  et.dispatchEvent(new Event('f'));
  assertEquals('Should have been called once', 1, fi);
  assertEquals(0, gi);

  et.removeEventListener('f', f);
  et.dispatchEvent(new Event('f'));
  assertEquals('Should not have been called again', 1, fi);

  et.dispatchEvent(new Event('g'));
  assertEquals('Should have been called once', 1, gi);
}

function testHandleEvent() {
  var fi = 0;
  var f = {
    handleEvent: function(e) {
      fi++;
    }
  };

  var gi = 0;
  var g = {
    handleEvent: function(e) {
      gi++;
    }
  };

  var et = new EventTarget;
  et.addEventListener('f', f);
  et.addEventListener('g', g);

  // Adding again should not cause it to be called twice
  et.addEventListener('f', f);
  et.dispatchEvent(new Event('f'));
  assertEquals('Should have been called once', 1, fi);
  assertEquals(0, gi);

  et.removeEventListener('f', f);
  et.dispatchEvent(new Event('f'));
  assertEquals('Should not have been called again', 1, fi);

  et.dispatchEvent(new Event('g'));
  assertEquals('Should have been called once', 1, gi);
}

function testPreventDefault() {
  var i = 0;
  function prevent(e) {
    i++;
    e.preventDefault();
  }

  var j = 0;
  function pass(e) {
    j++;
  }

  var et = new EventTarget;
  et.addEventListener('test', pass);

  assertTrue(et.dispatchEvent(new Event('test')));
  assertEquals(1, j);

  et.addEventListener('test', prevent);

  console.log('NOW');
  assertFalse(et.dispatchEvent(new Event('test')));
  assertEquals(2, j);
  assertEquals(1, i);
}


function testReturnFalse() {
  var i = 0;
  function prevent(e) {
    i++;
    return false;
  }

  var j = 0;
  function pass(e) {
    j++;
  }

  var et = new EventTarget;
  et.addEventListener('test', pass);

  assertTrue(et.dispatchEvent(new Event('test')));
  assertEquals(1, j);

  et.addEventListener('test', prevent);

  assertFalse(et.dispatchEvent(new Event('test')));
  assertEquals(2, j);
  assertEquals(1, i);
}

</script>
</body>
</html>