2-8 指令

Posted 斯人也

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2-8 指令

内容简介

  • 解析最简单的指令hello:匹配模式restrict

  • 解析最简单的指令hello:template、templateUrl、$templateCache

  • 解析最简单的指令hello:replace与translude

  • comile与link(操作元素、添加css样式、绑定事件)

  • 指令与控制器之间的交互

  • 指令间的交互

  • scope的类型与独立scope

  • scope的绑定策略

  • 实例解析Expander

  • 实例解析Accordion

  • 指令的运行原理:compile和link

  • 总结:ERP类型的系统必备的UI组件

  • 总结:互联网/电商型系统必备的UI组件

  • 第三方指令库angular-ui

  • Directive思想的起源和原理概述

1. 解析最简单的指令hello:匹配模式restrict

restrict:匹配模式。它有4个选项,分别为

  • A 属性attribute
  • E 元素element
  • M 注释comment
  • C 样式中的class

属性方式

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>指令</title>
    <script src="../node_modules/angular/angular.js"></script>
    <script src="js/HelloAngular_Directive.js"></script>
</head>
<body ng-app="myApp">
<div hello></div>
</body>
</html>
/**
 * Created by engoo-ypf on 2017/3/6.
 */
var app=angular.module(‘myApp‘,[]);
app.directive(‘hello‘,function () {
    return{
        restrict:‘A‘,
        template:‘<div> hi everyone!</div>‘,
        replace:true
    }
})

渲染后结果:
技术分享

元素方式

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>指令</title>
    <script src="../node_modules/angular/angular.js"></script>
    <script src="js/HelloAngular_Directive.js"></script>
</head>
<body ng-app="myApp">
<hello></hello>
</body>
</html>
/**
 * Created by engoo-ypf on 2017/3/6.
 */
var app=angular.module(‘myApp‘,[]);
app.directive(‘hello‘,function () {
    return{
        restrict:‘E‘,
        template:‘<div> hi everyone!</div>‘,
        replace:true
    }
})

渲染后结果:
技术分享

注释方式

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>指令</title>
    <script src="../node_modules/angular/angular.js"></script>
    <script src="js/HelloAngular_Directive.js"></script>
</head>
<body ng-app="myApp">
<!--  directive:hello -->
</body>
</html>

注意:指令``的写法。它的前后都有空格。这个坑一定要注意啊!!!

/**
 * Created by engoo-ypf on 2017/3/6.
 */
var app=angular.module(‘myApp‘,[]);
app.directive(‘hello‘,function () {
    return{
        restrict:‘M‘,
        template:‘<div> hi everyone!</div>‘,
        replace:true
    }
})

渲染后结果:
技术分享

样式方式

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>指令</title>
    <script src="../node_modules/angular/angular.js"></script>
    <script src="js/HelloAngular_Directive.js"></script>
</head>
<body ng-app="myApp">
<!--class样式指令-->
<div class="hello"></div>
</body>
</html>
/**
 * Created by engoo-ypf on 2017/3/6.
 */
var app=angular.module(‘myApp‘,[]);
app.directive(‘hello‘,function () {
    return{
        restrict:‘C‘,
        template:‘<div> hi everyone!</div>‘,
        replace:true
    }
})

渲染后:
技术分享

四种模式的使用场景

指令含义示例
A 属性(默认) <div my-menu=‘Products‘></div>
E 元素 <my-menu title=Products></my-menu>
M 注释 <!-- directive:my-menu Products -->
C 样式类 <div class=‘my-menu:Products‘></div>
  • 推荐使用元素和属性的方式使用指令
  • 当需要创建带有自己的模板的指令时,使用元素名称的方式创建指令
  • 当需要为有的html标签增加功能时,使用属性的方式创建指令

2. 解析最简单的指令hello:template、templateUrl、$templateCache

当我们使用指令的时候,每次都要在js中去Template去写html会很痛苦。为此Angular为我们准备了templateUrl。

templateUrl

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="../node_modules/angular/angular.js"></script>
    <script src="js/templateUrl.js"></script>
</head>
<body ng-app="myApp">
<hello></hello>
</body>
</html>
/**
 * Created by engoo-ypf on 2017/3/6.
 */
var app=angular.module(‘myApp‘,[]);
app.directive(‘hello‘,function () {
    return{
        reactive:‘E‘,
        templateUrl:‘tpls/tpls1.html‘,
        replace:true
    }
})
<div style="color: rebeccapurple; font-size: 50px">我是模板</div>

渲染后页面:
技术分享

$templateCache

如果我们编写的模板不仅仅是在现有的指令要使用,其他的指令也要使用该模板。我们就可以$templateCache。它可以将我们的模板进行缓存起来。

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="../node_modules/angular/angular.js"></script>
    <script src="js/templateCache.js"></script>
</head>
<body ng-app="myApp">
<hello></hello>
</body>
</html>
/**
 * Created by engoo-ypf on 2017/3/6.
 */
var app=angular.module(‘myApp‘,[]);
// 注射器加载完所有模块时,此方法执行一次
app.run(function ($templateCache) {
    $templateCache.put(‘helloTemple.html‘,‘<div>hello everyone!!!</div>‘)
});
app.directive(‘hello‘,function ($templateCache) {
    return{
        restrict:‘E‘,
        template:$templateCache.get(‘helloTemple.html‘),
        replace:true
    }
})

3. 解析最简单的指令hello:replace与translude

前面我们都是使用replace来替换页面中内容,那么如果我们不想替换,而是想在里面追加。那么我就可以使用translude

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="../node_modules/angular/angular.js"></script>
    <script src="js/transclude.js"></script>
</head>
<body ng-app="myApp">
<hello>
    <div>我是页面内容</div>
</hello>
</body>
</html>
/**
 * Created by engoo-ypf on 2017/3/6.
 */
var app=angular.module(‘myApp‘,[]);
app.directive(‘hello‘,function () {
    return{
        restrict:‘E‘,
        transclude:true,
        template:‘<div>hello everyone! <div ng-transclude></div></div>‘
    }
})

4. comile与link(操作元素、添加css样式、绑定事件)

 

技术分享

1488784946835.jpg

技术分享

 

5. 指令与控制器之间的交互

采用link的方式来进行交互。

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="../node_modules/angular/angular.js"></script>
    <script src="js/Directive&Controller.js"></script>
</head>
<body ng-app="myApp">
<div ng-controller="myCtrl">
    <loader >滑动加载</loader>
</div>
</body>
</html>
/**
 * Created by engoo-ypf on 2017/3/6.
 */
var app=angular.module(‘myApp‘,[]);
app.controller(‘myCtrl‘,[‘$scope‘,function ($scope) {
    $scope.loadData=function () {
        console.log(‘数据加载中~~~~‘);
    }
}])

app.directive(‘loader‘,function () {
    return{
        restrict:‘AE‘,
        link:function (scope,element,attr) {
            //当鼠标滑动到该指令的时候,执行下面代码
            element.bind(‘mouseenter‘,function () {
                // scope.loadData();  直接调用
                scope.$apply(‘loadData()‘) //也可以这样调用
            })
        }
    }
})

那么如果我们有多个指令需要调用不同的Controller中的function如何做呢?

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="../node_modules/angular/angular.js"></script>
    <script src="js/Directive&Controller.js"></script>
</head>
<body ng-app="myApp">
<div ng-controller="myCtrl">
    <loader howLoadData="loadData1()">滑动加载1</loader>
    <loader howLoadData="loadData2()">滑动加载2</loader>
</div>
</body>
</html>
/**
 * Created by engoo-ypf on 2017/3/6.
 */
var app=angular.module(‘myApp‘,[]);
app.controller(‘myCtrl‘,[‘$scope‘,function ($scope) {
    $scope.loadData1=function () {
        console.log(‘数据1加载中~~~~‘);
    }
    $scope.loadData2=function () {
        console.log(‘数据2加载中~~~~‘);
    }
}])

app.directive(‘loader‘,function () {
    return{
        restrict:‘AE‘,
        link:function (scope,element,attr) {
            //当鼠标滑动到该指令的时候,执行下面代码
            element.bind(‘mouseenter‘,function () {
                // scope.loadData();
				//这里有个坑:html中写的属性名字,在这里必须全部转成小写
                scope.$apply(attr.howloaddata)
            })
        }
    }
})

6. 指令间的交互

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="node_modules/angular/angular.js"></script>
    <script src="src/js/Directive&Directive.js"></script>
</head>
<body ng-app="myApp">
<div class="row">
    <div class="col-md-3">
        <superman strength>动感超人1---力量</superman>
    </div>
</div>
<div class="row">
    <div class="col-md-3">
        <superman strength speed>动感超人2---力量+敏捷</superman>
    </div>
</div>
<div class="row">
    <div class="col-md-3">
        <superman strength speed light>动感超人2---力量+敏捷+发光</superman>
    </div>
</div>
</body>
</html>
/**
 * Created by engoo-ypf on 2017/3/6.
 */
var app=angular.module(‘myApp‘,[]);
app.directive(‘superman‘,function () {
    return{
        // 创建独立的作用域
        scope:{},
        restrict:‘AE‘,
        // 指令内部的Controller。主要是用来暴露本身的方法供其它指令调用
        controller:function ($scope) {
            //给指令暴露出3个方法,以供其它指令调用
            $scope.abilities=[];
            this.addStrength=function () {
                $scope.abilities.push(‘strength‘);
            };
            this.addSpeed=function () {
                $scope.abilities.push(‘speed‘);
            };
            this.addLight=function () {
                $scope.abilities.push(‘light‘);
            };
        },
        link:function (scope,element,attrs) {
            element.addClass(‘btn btn-primary‘);
            element.bind(‘mouseenter‘,function () {
                console.log(scope.abilities);
            })
        }
    }
})

app.directive(‘strength‘,function () {
    return{
        //表示现在的指令时依赖于superman指令
        require:‘^superman‘,
        link:function (scope,element,attrs,supermanCtrl) {
            supermanCtrl.addStrength();
        }
    }
})

app.directive(‘speed‘,function () {
    return{
        //表示现在的指令时依赖于superman指令
        require:‘^superman‘,
        link:function (scope,element,attrs,supermanCtrl) {
            supermanCtrl.addSpeed();
        }
    }
})
app.directive(‘light‘,function () {
    return{
        //表示现在的指令时依赖于superman指令
        require:‘^superman‘,
        link:function (scope,element,attrs,supermanCtrl) {
            supermanCtrl.addLight();
        }
    }
})

7. scope的类型与独立scope

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="../node_modules/angular/angular.js"></script>
    <script src="js/isolateScope.js"></script>
</head>
<body ng-app="myApp">
<hello></hello>
<hello></hello>
<hello></hello>
<hello></hello>
</body>
</html>
/**
 * Created by engoo-ypf on 2017/3/6.
 */
var app = angular.module(‘myApp‘, []);
app.directive(‘hello‘, function () {
    return {
        restrict: ‘AE‘,
		//这是这句后,我们的指令中的scope就会独立使用,不会相互污染啦
        scope: {},
        template: ‘<div><input type="text" ng-model="userName"/>{{userName}}</div>‘,
        replace: true
    }
})

8. Scope的绑定策略

参数解释
@ 把当前属性作为字符串传递(不能传递对象)。你还可以绑定来自外层scope的值,在属性值中插入{{}} 即可
= 与父级scope中的属性进行双向绑定
& 传递一个来自父级scope的函数,稍后调用

@绑定

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="../node_modules/angular/angular.js"></script>
    <script src="js/scopeAt.js"></script>
</head>
<body ng-app="myApp">
<div ng-controller="MyCtrl">
    <drink flavor="{{ctrlFlavor}}"></drink>
</div>
</body>
</html>
/**
 * Created by engoo-ypf on 2017/3/6.
 */
var app=angular.module(‘myApp‘,[]);
app.controller(‘MyCtrl‘,[‘$scope‘,function ($scope) {
    $scope.ctrlFlavor=‘百威‘
}])

app.directive(‘drink‘,function () {
  return{
      restrict:‘AE‘,
      scope:{
          flavor:‘@‘
      },
      template:‘<div>{{flavor}}</div>‘
  }
})

=绑定

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="node_modules/angular/angular.js"></script>
    <script src="src/js/scopeEqual.js"></script>
</head>
<body ng-app="myApp">
<div ng-controller="MyCtrl">
    指令:
    <drink flavor="ctrlFlavor"></drink>
    <br>
    控制器:
    <input type="text" ng-model="ctrlFlavor">
    <br>
</div>
</body>
</html>
/**
 * Created by engoo-ypf on 2017/3/6.
 */
var app=angular.module(‘myApp‘,[]);
app.controller(‘MyCtrl‘,[‘$scope‘,function ($scope) {
    $scope.ctrlFlavor=‘百威‘
}])

app.directive(‘drink‘,function () {
    return{
        restrict:‘AE‘,
        scope:{
            flavor:‘=‘
        },
        template:‘<input type="text" ng-model="flavor"/>‘
    }
})

& 传递一个来自父级scope的函数,稍后调用

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <script src="../node_modules/angular/angular.js"></script>
    <script src="js/scopeAnd.js"></script>
</head>
<body ng-app="myApp">
<div ng-controller="MyCtrl">
    <greeting greet="sayHello(name)"></greeting>
    <greeting greet="sayHello(name)"></greeting>
    <greeting greet="sayHello(name)"></greeting>
    <greeting greet="sayHello(name)"></greeting>
</div>
</body>
</html>
/**
 * Created by yangp on 2017/3/6.
 */
var app=angular.module(‘myApp‘,[]);
app.controller(‘MyCtrl‘,[‘$scope‘,function ($scope) {
    $scope.sayHello=function (name) {
        alert(‘Hello‘+name);
    }
}]);

app.directive(‘greeting‘,function () {
    return{
        restrict:‘AE‘,
        scope:{
            greet:‘&‘
        },
        template:‘<input type="text" ng-model="userName"/><br>‘+
        ‘<button ng-click="greet({name:userName})">Greet</button><br>‘
    }
})

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