我有这些JavaScript文件。这实在是小的测试项目,以了解MVC是如何使用的JavaScript。当我尝试点击“删除Bloak”按钮,没有任何反应,除了与最后一个按钮,其ID为100的其他按钮没有连接到他们的任何点击事件。为什么?
Controller.js
var BloakController = function BloakController(model, view) {
this.model = model;
this.view = view;
}
BloakController.prototype.init = function init() {
this.view.onAddBloak = this.addBloak.bind(this);
this.view.onDeleteBloak = this.deleteBloak.bind(this);
this.view.onGetAllBloaks = this.getAllBloaks.bind(this);
}
BloakController.prototype.addBloak = function addBloak() {
}
BloakController.prototype.getAllBloaks = function getAllBloaks() {
this.model.getAllBloaks(this.getAllBloaksList.bind(this));
}
BloakController.prototype.getAllBloaksList = function getAllBloaksList(allBloaksList) {
for (var i = 0; i < allBloaksList.length; i++) {
var bloak = allBloaksList[i];
var bloakDataObjectModel = {
title: bloak.title,
body: bloak.body,
userId: bloak.userId,
id: bloak.id
};
this.view.render(bloakDataObjectModel);
}
}
BloakController.prototype.deleteBloak = function deleteBloak(id) {
this.model.deleteBloak(id, this.getAllBloaksList.bind(this));
}
Model.js
var BloakModel = function BloakModel(XMLHttpRequest) {
this.XMLHttpRequest = XMLHttpRequest;
}
BloakController.prototype.addBloak = function addBloak() {
}
BloakModel.prototype.getAllBloaks = function getAllBloaks(callback) {
var request = new this.XMLHttpRequest;
request.onload = function onLoad(e) {
var ajaxResponse = JSON.parse(e.currentTarget.responseText);
callback(ajaxResponse);
}
request.open('GET', 'https://jsonplaceholder.typicode.com/posts', true);
request.send();
}
BloakModel.prototype.deleteBloak = function deleteBloak(id, callback) {
console.log(id);
var request = new this.XMLHttpRequest;
request.onload = function onLoad(e) {
var ajaxResponse = JSON.parse(e.currentTarget.responseText);
callback(ajaxResponse);
}
request.open('DELETE', 'https://jsonplaceholder.typicode.com/posts/' + id, true);
request.send();
}
View.js
var BloakView = function BloakView(domElement) {
this.domElement = domElement;
this.onAddBloak = null;
this.onDeleteBloak = null;
this.onGetAllBloaks = null;
}
BloakView.prototype.render = function render(bloakDataObjectModel) {
this.domElement.innerHTML += '<div class="bloakContainer"><h3>' + bloakDataObjectModel.title + '</h3><p class="bloakContent">' + bloakDataObjectModel.body + '</p><label class="bloakAuthor">' + bloakDataObjectModel.userId + '</label><br /><label class="bloakDate">' + bloakDataObjectModel.id + '</label><br /><input id=' + bloakDataObjectModel.id + ' type="button" value="Delete Bloak" /></div>';
var addBloakButton = document.getElementById('addBloakButton');
var deleteBloakButton = document.getElementById(bloakDataObjectModel.id);
addBloakButton.addEventListener('click', this.onAddBloak);
deleteBloakButton.addEventListener('click', this.onDeleteBloak);
}
App.js
var bloakModel = new BloakModel(XMLHttpRequest);
var targetElement = document.getElementById('bloaksContainer');
var bloakView = new BloakView(targetElement);
var bloakController = new BloakController(bloakModel, bloakView);
bloakController.init();
bloakController.getAllBloaks();
事实证明我完全错了,已经做更多的研究,看起来像使用innerHTML
属性将导致所有的子元素的破坏,read more about it here。无论哪种方式,只要仍然有效的解决方案,事实证明,我不知道我自己。
我已经意识到我错了最初,如果我是正确的,那么你就会有一个错误,说明你不能附加一个事件监听器null
或undefined
,是我不好,愚蠢的错误在我的一部分!
已经很简单看过了你的代码,我认为这是肯定地说,你的渲染功能有点故障,由于使用innerHTML
,它不是解析更新的HTML的事件侦听器的工作速度不够快...
已经测试它自己,而刚刚做了以下内容:
setTimeout(() => {
var addBloakButton = document.getElementById('addBloakButton');
var deleteBloakButton = document.getElementById(bloakDataObjectModel.id);
addBloakButton.addEventListener('click', this.onAddBloak);
deleteBloakButton.addEventListener('click', this.onDeleteBloak);
}, 10);
有效。所以,如果你不想改变太多,你可以做什么,我之前所做的那样,或者,你可以做沿着此线的东西:
var div = document.createElement("div");
div.innerHTML = '<div class="bloakContainer"><h3>' + bloakDataObjectModel.title + '</h3><p class="bloakContent">' + bloakDataObjectModel.body + '</p><label class="bloakAuthor">' + bloakDataObjectModel.userId + '</label><br /><label class="bloakDate">' + bloakDataObjectModel.id + '</label><br /><input id=' + bloakDataObjectModel.id + ' type="button" value="Delete Bloak" /></div>';
this.domElement.append(div);
var addBloakButton = document.getElementById('addBloakButton');
var deleteBloakButton = div.querySelector('input[id*="' + bloakDataObjectModel.id + '"]');
addBloakButton.addEventListener('click', this.onAddBloak);
deleteBloakButton.addEventListener('click', this.onDeleteBloak);
此外,我会做一个更坚实可靠的办法是实现视图内的onRender
功能,本质上阐明,一次且仅一次有关HTML的所有已经呈现,随后击发onRender
方法。或者,也许像view.dispatchEvents
,等...具体这个例子中,我会在控制器内运行这样的功能,所以一旦getAllBloaksList
已使所有的相关数据,就可以触发一个dispatchEvents
功能,就像这样:
// Within the controller part...
BloakController.prototype.getAllBloaksList = function getAllBloaksList(allBloaksList) {
for (var i = 0; i < allBloaksList.length; i++) {
var bloak = allBloaksList[i];
var bloakDataObjectModel = {
title: bloak.title,
body: bloak.body,
userId: bloak.userId,
id: bloak.id
};
this.view.render(bloakDataObjectModel);
}
this.view.dispatchEvents();
};
// .. Within the View part...
BloakView.prototype.dispatchEvents = function () {
var list = this.domElement.querySelectorAll(".bloakContainer");
var todo = this.onDeleteBloak;
list.forEach(function (div) {
var deleteButton = div.querySelector("input[type=button]");
deleteButton.onclick = function () {
todo(this.id);
};
});
};
// Controller.
var BloakController = function BloakController(model, view) {
this.model = model;
this.view = view;
};
BloakController.prototype.init = function init() {
this.view.onAddBloak = this.addBloak.bind(this);
this.view.onDeleteBloak = this.deleteBloak.bind(this);
this.view.onGetAllBloaks = this.getAllBloaks.bind(this);
};
BloakController.prototype.addBloak = function addBloak() {
// todo
};
BloakController.prototype.getAllBloaks = function getAllBloaks() {
this.model.getAllBloaks(this.getAllBloaksList.bind(this));
};
BloakController.prototype.getAllBloaksList = function getAllBloaksList(allBloaksList) {
for (var i = 0; i < allBloaksList.length; i++) {
var bloak = allBloaksList[i];
var bloakDataObjectModel = {
title: bloak.title,
body: bloak.body,
userId: bloak.userId,
id: bloak.id
};
this.view.render(bloakDataObjectModel);
}
this.view.dispatchEvents();
};
BloakController.prototype.deleteBloak = function deleteBloak(id) {
this.model.deleteBloak(id, this.getAllBloaksList.bind(this));
};
// Model.
var BloakModel = function BloakModel(XMLHttpRequest) {
this.XMLHttpRequest = XMLHttpRequest;
};
BloakController.prototype.addBloak = function addBloak() {
// todo
};
BloakModel.prototype.getAllBloaks = function getAllBloaks(callback) {
var request = new this.XMLHttpRequest;
request.onload = function onLoad(e) {
var ajaxResponse = JSON.parse(e.currentTarget.responseText);
callback(ajaxResponse);
}
request.open('GET', 'https://jsonplaceholder.typicode.com/posts', true);
request.send();
};
BloakModel.prototype.deleteBloak = function deleteBloak(id, callback) {
console.log(id);
var request = new this.XMLHttpRequest;
request.onload = function onLoad(e) {
var ajaxResponse = JSON.parse(e.currentTarget.responseText);
callback(ajaxResponse);
}
request.open('DELETE', 'https://jsonplaceholder.typicode.com/posts/' + id, true);
request.send();
};
// View.
var BloakView = function BloakView(domElement) {
this.domElement = domElement;
this.onAddBloak = null;
this.onDeleteBloak = null;
this.onGetAllBloaks = null;
};
BloakView.prototype.render = function render(bloakDataObjectModel) {
this.domElement.innerHTML += '<div class="bloakContainer"><h3>' + bloakDataObjectModel.title + '</h3><p class="bloakContent">' + bloakDataObjectModel.body + '</p><label class="bloakAuthor">' + bloakDataObjectModel.userId + '</label><br /><label class="bloakDate">' + bloakDataObjectModel.id + '</label><br /><input id=' + bloakDataObjectModel.id + ' type="button" value="Delete Bloak" /></div>';
}
BloakView.prototype.dispatchEvents = function() {
var list = this.domElement.querySelectorAll(".bloakContainer");
var todo = this.onDeleteBloak;
var addBloakButton = document.getElementById('addBloakButton');
addBloakButton.addEventListener('click', this.onAddBloak);
list.forEach(function(div) {
var deleteButton = div.querySelector("input[type=button]");
deleteButton.onclick = function() {
todo(this.id);
};
});
};
// App.
var bloakModel = new BloakModel(XMLHttpRequest);
var targetElement = document.getElementById('bloaksContainer');
var bloakView = new BloakView(targetElement);
var bloakController = new BloakController(bloakModel, bloakView);
bloakController.init();
bloakController.getAllBloaks();
<button id="addBloakButton">Add</button>
<div id="bloaksContainer">
<!-- DHTML -->
</div>
代码this.domElement.innerHTML += ...;
被incorrect.You使用的是+ =操作这增加了一些与本身,然后分配新的值。
新价值是现有的innerHTML和新的HTML的结果。因此,新的价值[HTML]不会有先前添加的事件处理程序,将刚才复制的HTML。
您可以使用appendChild方法来添加新的元素。
此外,你应该避免使用具有的innerHTML的for-loop
因为它会不断更新DOM,你可能会看到屏幕上闪烁。如果必须使用innerHTML,你应该
事件代表团将事件绑定到一个顶层容器,这样你就不需要担心事件侦听器连接到每个项目的技术。
你可以阅读更多的DOM here。