练习题
一、点击事件控制标签颜色
1、有 红、黄、蓝 三个按钮，以及一个200x200矩形框box，点击不同的按钮，box的颜色会被切换为指定的颜色
<!DOCTYPE html>
<html lang="zh">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<div id="app">
<form action="" style="margin: 30px;">
<p @click="tag" :style="{ w,height: h, backgroundColor: bgc }"></p>
<input type="button" value="红" @click="tag($event,'red')">
<input type="button" value="黄" @click="tag($event,'yellow')">
<input type="button" value="蓝" @click="tag($event,'blue')">
</form>
</div>
</body>
<script src="js/vue.js"></script>
<script>
new Vue({
el:'#app',
data:{
h: '200px',
w: '200px',
bgc: 'red'
},
methods:{
tag (a,b) {
this.bgc = b
}
}
})
</script>
</html>
二、实现点击次数，变换页面标签的颜色
2、有一个200x200矩形框wrap，点击wrap本身，记录点击次数，如果是1次wrap为pink色，2次wrap为green色，3次wrap为cyan色，4次重新回到pink色，依次类推
<!DOCTYPE html>
<html lang="zh">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<div id="app">
<form action="#" style="margin: 30px;">
<p @click="tag" :style="{ w,height: h, backgroundColor: bgc}"></p>
</form>
</div>
</body>
<script src="js/vue.js"></script>
<script>
let num = 0;
new Vue({
el:'#app',
data:{
h: '200px',
w: '200px',
bgc: 'yellow'
},
methods:{
tag () {
num += 1;
if (num==1){
this.bgc = 'pink'
}else {if (num==2){
this.bgc = 'green'
}else {
this.bgc = 'cyan';
num = 0
}}
}
}
})
</script>
</html>
三、周期性实现颜色的旋转变色
1、如图：图形初始左红右绿，点击一下后变成上红下绿，再点击变成右红左绿，再点击变成下红上绿，依次类推
2、可以将图编程自动旋转
<!DOCTYPE html>
<html lang="zh">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<div id="app">
<form action="" style="margin: 30px;">
<p @click="tag" :style="{ w,height: h, background: bgc, borderRadius:rad}"></p>
</form>
</div>
</body>
<script src="js/vue.js"></script>
<script>
let num = 0;
let app = new Vue({
el:'#app',
data:{
h: '200px',
w: '200px',
//实现页面的过度（颜色）
bgc: 'linear-gradient(to top, red 50%, green 50%)',
rad: '50%'
},
methods:{
tag () {
num += 1;
if (num==1){
// 控制方向
this.bgc = 'linear-gradient(to top, red 50%, green 50%)'
}else {if (num==2){
this.bgc = 'linear-gradient(to left, red 50%, green 50%)'
}else {if (num==3) {
this.bgc = 'linear-gradient(to bottom,red 50%, green 50%)'
}else {
this.bgc = 'linear-gradient(to right, red 50%, green 50%)';
num = 0
}
}}
}
}
});
function funcTest(){
// 按照指定的周期（以毫秒计）来调用函数
window.setInterval(app.tag,666);
}
// 页面加载完直接调用 该方法
window.onload = funcTest;
</script>
</html>