使用setInterval和JavaScript

Question

我正在使用Notification API，但我无法使它与SetInterval（）一起工作，有人可以指出我做错了什么。只要我点击该事件，通知只会显示一次。这里是我的代码：

document.addEventListener('DOMContentLoaded', function() { 
document.getElementById('notifyBtn').addEventListener('click', function() { 

    if (!('Notification' in window)) { 
     alert('Web Notification is not supported'); 
     return; 
    } else { 
     setInterval(Notification.requestPermission(function(permission) { 
      var notification = new Notification("Hi there!", { 
       body: 'I am here to talk about HTML5 Web Notification API', 
       icon: 'icon.png', 
       dir: 'auto' 
      }); 
      setTimeout(function() { 
       notification.close(); 
      }, 2000); 
     }),5000); 

    } 
    ; 
}); 
}); 

我真的被卡住了，请halp。

Answer 1

您需要将有效回调传递给setInterval()。相反，您正在通过某种方法的结果。试试这个：

setInterval(function() { 
    Notification.requestPermission(function(permission) { 
     var notification = new Notification("Hi there!", { 
      body: 'I am here to talk about HTML5 Web Notification API', 
      icon: 'icon.png', 
      dir: 'auto' 
     }); 
     setTimeout(notification.close, 2000); 
    })}, 5000); 

奖励：看我如何简化您的setTimeout回调，由刚好路过notification.close方法本身，与其说这是在匿名函数。更干净。

Answer 2

总结你的方法在匿名函数

document.addEventListener('DOMContentLoaded', function() { 
document.getElementById('notifyBtn').addEventListener('click', function() { 

    if (!('Notification' in window)) { 
     alert('Web Notification is not supported'); 
     return; 
    } else { 
     setInterval(function(){Notification.requestPermission(function(permission) { 
      var notification = new Notification("Hi there!", { 
       body: 'I am here to talk about HTML5 Web Notification API', 
       icon: 'icon.png', 
       dir: 'auto' 
      }); 
      setTimeout(function() { 
       notification.close(); 
      }, 2000); 
     })},5000); 

    } 
    ; 
}); 
}); 

Answer 3

，我发现这样的事情：

document.addEventListener('DOMContentLoaded', function() { 
document.getElementById('notifyBtn').addEventListener('click', function() { 
    if (!('Notification' in window)) { 
     alert('Web Notification is not supported'); 
     return; 
    } else { 
     setInterval(notify, 5000); 
    } 
}); 
function notify() { 
    Notification.requestPermission(function(permission) { 
      var n = new Notification("Hi there!", { 
       body: 'I am here to talk about HTML5 Web Notification API', 
       icon: 'icon.png', 
       dir: 'auto' 
      }) 
      setTimeout(function(){n.close()}, 2000) 
     }) 

}