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Также идентификаторы должны быть уникальными
$(function() {
$("#opt").on("change", function() {
$(".box3").toggle(this.value == "three"); // toggle will show if true, hide if false
}).change()
})
.header {
width: 100%;
height: 40px;
background: #f4f3f1;
border: 1px solid #dbdfe5;
text-align: center;
font-size: 20px;
padding-top: 0px;
color: green;
font-weight: bold;
}
.container {
width: 100%;
min-height: 150px;
padding-top: 2px;
display: flex;
}
.container .box1 {
background: #ffffff;
border-radius: 3px;
border: 2px solid #dbdfe5;
flex: 1;
overflow: auto;
}
.container .box1 #first {
width: 100%;
height: 35px;
border: 1px solid #dbdfe5;
padding-bottom: 10px;
border-radius: 1px;
background: #f4f3f1;
}
.container .box1.box2 {
background: #ffffff;
border-radius: 3px;
overflow: auto;
}
.container .box1.box2 #second {
width: 100%;
height: 35px;
border: 1px solid #dbdfe5;
border-radius: 5px;
padding-bottom: 10px;
background: #f4f3f1;
}
.container .box1.box2.box3 #third {
width: 100%;
height: 35px;
border: 1px solid #dbdfe5;
border-radius: 5px;
padding-bottom: 10px;
background: #f4f3f1;
}
.tabb {
float: left;
margin-left: 10px;
margin: 5px;
display: inline-block;
padding: 6px 12px;
border-radius: 5px;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<body>
<div class="header">
<select class="tabb" name="opt" id="opt">
<option value="two">Normal </option>
<option value="three">Three view</option>
</select>
Demo </div>
<div class="container">
<div class="box1">
<div id="first">
<center>Inside Box1</center>
</div>
<center>Main Box1</center>
</div>
<div class="box1 box2">
<div id="second">
<center>Inside Box2</center>
</div>
<center>Main Box2</center>
</div>
<div class="box1 box2 box3">
<div id="third">
<center>Inside Box3</center>
</div>
<center>Main Box3</center>
</div>
</div>
</body>
Чтобы добавить представления, попробуйте следующее:
var views = {
"three": ".box3",
"four": ".box3,.box4"
}
$(function() {
$("#opt").on("change", function() {
var view = views[this.value]; // if three or four
$(".box3,.box4").hide(); // hide anyway
if (view) $(view).show(); // show box2 or box3 and box4
}).change()
})
.header {
width: 100%;
height: 40px;
background: #f4f3f1;
border: 1px solid #dbdfe5;
text-align: center;
font-size: 20px;
padding-top: 0px;
color: green;
font-weight: bold;
}
.container {
width: 100%;
min-height: 150px;
padding-top: 2px;
display: flex;
}
.container .box1 {
background: #ffffff;
border-radius: 3px;
border: 2px solid #dbdfe5;
flex: 1;
overflow: auto;
}
.container .box1 #first {
width: 100%;
height: 35px;
border: 1px solid #dbdfe5;
padding-bottom: 10px;
border-radius: 1px;
background: #f4f3f1;
}
.container .box1.box2 {
background: #ffffff;
border-radius: 3px;
overflow: auto;
}
.container .box1.box2 #second {
width: 100%;
height: 35px;
border: 1px solid #dbdfe5;
border-radius: 5px;
padding-bottom: 10px;
background: #f4f3f1;
}
.container .box1.box2.box3 #third {
width: 100%;
height: 35px;
border: 1px solid #dbdfe5;
border-radius: 5px;
padding-bottom: 10px;
background: #f4f3f1;
}
.container .box1.box2.box4 #fourth {
width: 100%;
height: 35px;
border: 1px solid #dbdfe5;
border-radius: 5px;
padding-bottom: 10px;
background: #f4f3f1;
}
.tabb {
float: left;
margin-left: 10px;
margin: 5px;
display: inline-block;
padding: 6px 12px;
border-radius: 5px;
}
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<body>
<div class="header">
<select class="tabb" name="opt" id="opt">
<option value="two">Normal </option>
<option value="three">Three view</option>
<option value="four">Four view</option>
</select>
Demo </div>
<div class="container">
<div class="box1">
<div id="first">
<center>Inside Box1</center>
</div>
<center>Main Box1</center>
</div>
<div class="box1 box2">
<div id="second">
<center>Inside Box2</center>
</div>
<center>Main Box2</center>
</div>
<div class="box1 box2 box3">
<div id="third">
<center>Inside Box3</center>
</div>
<center>Main Box3</center>
</div>
<div class="box1 box2 box4">
<div id="fourth">
<center>Inside Box4</center>
</div>
<center>Main Box4</center>
</div>
</div>
</body>