退出在Qt下开发的应用程序时，我收到以下错误：
file:///C:/Qt/5.10.0/mingw53_32/qml/QtQuick/Controls/Private/Control.qml:90:
ReferenceError: parent is not defined
从组件定义为：
import QtQuick 2.8
import QtGraphicalEffects 1.0
import QtQuick.Controls.Styles 1.4
import QtQuick.Extras 1.4
Item {
id:root
CircularGauge {
anchors.centerIn: root
}
}
如果行
anchors.centerIn: root
被删除，然后没有错误。我很确定只要CircularGauge以某种方式引用parent，就会产生错误，尽管设置了
parent:root
在仪表中没有帮助。知道是什么造成的吗？
答案 0 :(得分：0)
如果anchors.centerIn: root，则设置/* ==== Google font ==== */
@import url(http://fonts.googleapis.com/css?family=Roboto:400,300,700,900);
@import url('http://fonts.googleapis.com/css?family=Ek+Mukta:400,600,700');
* {
padding: 0;
margin: 0;
}
#logo {
padding: 0;
margin: 0;
width: 80px;
height: 80px;
margin: -0.6em 0;
}
#contact {
height: 150px;
}
html nav.navbar.navbar-custom {
padding: 0;
margin: 0;
}
body {
width: 100%;
height: 100%;
font-family: 'Ek Mukta', sans-serif;
font-weight: 300;
color: #666;
background-color: #fff;
font-size: 16px;
line-height: 1.6em;
font-weight: 400;
overflow-x: hidden;
}
html {
width: 100%;
height: 100%;
}
h1 {
font-size: 38px;
}
h2 {
font-size: 36px;
}
h3 {
font-size: 32px;
}
h4 {
font-size: 28px;
}
h5 {
font-size: 24px;
}
h6 {
font-size: 20px;
}
h1, h2, h4, h5, h6 {
margin: 0 0 30px;
font-family: 'Roboto', sans-serif;
font-weight: 400;
color: #111;
}
h3 {
margin: 0 0 30px;
font-family: 'Roboto', sans-serif;
font-weight: 400;
color: #008000 !important;
}
h1.h-xlight, h2.h-xlight, h3.h-xlight, h4.h-xlight, h5.h-xlight, h6.h-xlight {
font-weight: 200;
}
h1.h-light, h2.h-light, h3.h-light, h4.h-light, h5.h-light, h6.h-light {
font-weight: 300;
}
h1.h-bold, h2.h-bold, h3.h-bold, h4.h-bold, h5.h-bold, h6.h-bold {
font-weight: 600;
}
h1.font-light, h2.font-light, h3.font-light, h4.font-light, h5.font-light, h6.font-light {
color: #fff;
}
.big-heading {
font-size: 48px;
font-weight: 700;
}
p {
margin: 0 0 10px;
}
.text-center {
font-size: 20px;
}
.service-desc p {
font-size: 16px;
}
p.lead {
font-weight: 600;
}
.highlight-light {
background-color: rgba(255,255,255,.5);
padding: 20px;
display: inline-block;
color: #111;
}
.highlight-dark {
background-color: rgba(0,0,0,.5);
padding: 20px;
display: inline-block;
color: #fff;
}
.highlight-color {
padding: 20px;
display: inline-block;
}
a {
color: #666;
-webkit-transition: all .2s ease-in-out;
-moz-transition: all .2s ease-in-out;
transition: all .2s ease-in-out;
}
a:hover, a:focus {
text-decoration: none;
}
blockquote {
padding: 10px 20px;
margin: 0 0 20px;
font-size: 24px;
line-height: 1.5em;
font-weight: 300;
color: #999;
}
blockquote.bg-light {
background-color: rgba(255,255,255,.8);
padding: 20px;
color: #222;
}
blockquote.bg-dark {
background-color: rgba(0,0,0,.8);
padding: 20px;
}
blockquote strong {
font-weight: 700;
}
.light {
font-weight: 400;
}
.site-logo {
display: flex;
}
.site-logo a.brand {
color: #111;
text-transform: uppercase;
font-size: 32px;
font-family: 'Roboto', sans-serif;
font-weight: 900;
margin-top: 20px;
}
#navigation {
background: #fff;
z-index: 9999;
width: 100%;
box-sizing: border-box;
border-bottom: 1px solid #eee;
box-shadow: 0px 0px 20px rgba(0, 0, 0, 0.1);
}
div#navigation-sticky-wrapper {
position: relative;
z-index: 121;
}
.navbar {
margin-bottom: 0;
}
.navbar-brand {
font-weight: 700;
}
.navbar-brand:focus {
outline: 0;
}
.nav.navbar-nav {
background-color: rgba(255,255,255,.6);
}
.navbar-custom.top-nav-collapse .nav.navbar-nav {
background-color: rgba(0,0,0,0);
}
.navbar-custom ul.nav li a {
font-size: 16px;
letter-spacing: 1px;
color: #444;
text-transform: uppercase;
font-weight: 700;
}
.navbar-custom.top-nav-collapse ul.nav li a {
-webkit-transition: all .2s ease-in-out;
-moz-transition: all .2s ease-in-out;
transition: all .2s ease-in-out;
color: #fff;
}
.navbar-custom ul.nav ul.dropdown-menu {
border-radius: 0;
margin-top: 21px;
border-top: none;
}
.navbar-custom ul.nav li a:hover ul.dropdown-menu {
-webkit-transition: all .2s ease-in-out;
-moz-transition: all .2s ease-in-out;
transition: all .2s ease-in-out;
}
.navbar-custom ul.nav ul.dropdown-menu li {
border-bottom: 1px solid #f5f5f5;
}
.navbar-custom ul.nav ul.dropdown-menu li:last-child {
border-bottom: none;
}
.navbar-custom ul.nav ul.dropdown-menu li a {
padding: 10px 20px;
}
.navbar-custom ul.nav ul.dropdown-menu li a:hover {
background: #fefefe;
}
.navbar-custom.top-nav-collapse ul.nav ul.dropdown-menu li a {
color: #666;
}
.navbar-custom .nav li a {
-webkit-transition: background .3s ease-in-out;
-moz-transition: background .3s ease-in-out;
transition: background .3s ease-in-out;
}
.navbar-custom .nav li a:hover, .navbar-custom .nav li a:focus, .navbar-custom .nav li.active {
outline: 0;
background-color: rgba(255,255,255,.2);
}
.navbar-custom .nav li a:hover, .navbar-custom .nav li a:focus, .navbar-custom .nav li.active {
outline: 0;
background-color: rgba(255,255,255,.2);
}
.navbar-toggle {
padding: 4px 6px;
font-size: 14px;
color: #fff;
}
.navbar-toggle:focus, .navbar-toggle:active {
outline: 0;
}
hr {
margin-top: 10px;
}
hr.bold {
border-top: 3px solid #eee;
}
.divider-header {
display: block;
width: 40px;
height: 2px;
margin: 0 auto;
margin-bottom: 10px;
}
.divider-short {
display: block;
width: 60px;
height: 5px;
margin: 0 auto;
margin-bottom: 10px;
}
.marginbot-0 {
margin-bottom: 0 !important;
}
.marginbot-10 {
margin-bottom: 10px !important;
}
.marginbot-20 {
margin-bottom: 20px !important;
}
.marginbot-30 {
margin-bottom: 30px !important;
}
.marginbot-40 {
margin-bottom: 40px !important;
}
.marginbot-50 {
margin-bottom: 50px !important;
}
.marginbot-60 {
margin-bottom: 60px !important;
}
.marginbot-70 {
margin-bottom: 70px !important;
}
.marginbot-80 {
margin-bottom: 80px !important;
}
.marginbot-90 {
margin-bottom: 90px !important;
}
.marginbot-100 {
margin-bottom: 100px !important;
}
.margintop-0 {
margin-top: 0 !important;
}
.margintop-10 {
margin-top: 10px !important;
}
.margintop-20 {
margin-top: 20px !important;
}
.margintop-30 {
margin-top: 30px !important;
}
.margintop-40 {
margin-top: 40px !important;
}
.margintop-45 {
margin-top: 45px !important;
}
.margintop-50 {
margin-top: 50px !important;
}
#container-2 {
background-color: #EBB250;
}
.home-section {
padding-top: 20px;
padding-bottom: 20px;
display: block;
position: relative;
z-index: 120;
}
.home-section2 {
padding-top: 0px;
padding-bottom: 20px;
display: block;
position: relative;
z-index: 120;
}
.inner-section {
padding-top: 110px;
padding-bottom: 110px;
}
.home-section.nopadd-bot {
padding-bottom: 0;
}
.section-heading h2 {
font-size: 24px;
letter-spacing: 1px;
text-transform: uppercase;
margin-bottom: 10px;
}
.section-heading p {
font-weight: 300;
font-size: 20px;
line-height: 1.6em;
}
.color-dark .section-heading h2 {
color: #111;
}
.color-dark .section-heading p {
color: #444;
}
.color-dark .divider-short {
background: #666;
}
.color-dark .divider-header {
background: #666;
}
.color-light .divider-short {
background: #666;
}
.color-light .divider-header {
background: #666;
}
.color-light .section-heading h2 {
color: #fff;
}
.color-light .section-heading p {
color: #fefefe;
}
.color-light blockquote, .color-light p {
color: #fefefe;
}
.bg-white {
background: #fff;
}
.bg-gray {
background: #f9f9f9;
}
.bg-dark {
background: #404040;
}
.text-light {
color: #fff;
}
.hero {
background: url(../img/jardines/jardin0.jpg) no-repeat center center;
-webkit-background-size: cover;
-moz-background-size: cover;
-o-background-size: cover;
background-size: cover;
padding: 200px 0 200px 0;
height: auto;
}
.hero h1 {
font-size: 40px;
letter-spacing: 12px;
margin: 40px 0 10px;
font-weight: 900;
color: #fff;
}
.hero h1 span {
color: #a1a9b0;
display: inline-block;
}
.hero p {
font-size: 24px;
font-weight: 400;
color: #fefefe;
}
.learn-more-btn {
background: rgba(61, 201, 179, 1);
padding: 20px 40px;
border-radius: 5px;
-moz-border-radius: 5px;
-webkit-border-radius: 5px;
-o-border-radius: 5px;
color: #fff;
text-transform: uppercase;
letter-spacing: 1px;
display: inline-block;
-webkit-box-shadow: 0px 3px 0px 0px #309383;
-moz-box-shadow: 0px 3px 0px 0px #309383;
box-shadow: 0px 3px 0px 0px #309383;
margin: 60px 0 0;
font-weight: bold;
}
.learn-more-btn:hover, .learn-more-btn:focus {
background: rgba(61, 201, 179, 0.6);
color: #fff;
}
.intro {
width: 100%;
position: relative;
padding: 0;
}
.intro-inner {
width: 100%;
position: relative;
padding: 120px 0 20px;
}
.brand-heading {
font-size: 40px;
}
.intro-text {
font-size: 18px;
}
.carousel-inner img {
width: 100%;
max-height: 650px;
}
.carousel-control {
width: 0;
}
.carousel-control.left, .carousel-control.right {
opacity: 1;
filter: alpha(opacity=100);
background-image: none;
background-repeat: no-repeat;
text-shadow: none;
}
.carousel-control.left span {
padding: 0;
}
.carousel-control.right span {
padding: 0;
}
.carousel-control .glyphicon-chevron-left, .carousel-control .glyphicon-chevron-right, .carousel-control .icon-prev, .carousel-control .icon-next {
position: absolute;
top: 45%;
z-index: 5;
display: inline-block;
}
.carousel-control .glyphicon-chevron-left, .carousel-control .icon-prev {
left: 30px;
}
.carousel-control .glyphicon-chevron-right, .carousel-control .icon-next {
right: 30px;
}
.carousel-control.left span:hover, .carousel-control.right span:hover {
opacity: .7;
filter: alpha(opacity=70);
}
.carousel-inner > .item {
margin-left: 0;
margin-top: 0;
margin-bottom: 0;
padding-left: 0;
width: 100%;
height: auto;
}
.carousel-inner > .item > img, .carousel-inner > .item > a > img {
display: block;
max-width: 100%;
height: auto;
margin-left: 0;
padding-left: 0;
}
.header-text {
position: absolute;
top: 20%;
left: 1.8%;
right: auto;
width: 96.66666666666666%;
color: #fff;
}
.header-text h2 {
font-size: 40px;
}
.header-text h2 span {
padding: 10px;
color: #fff;
text-transform: uppercase;
}
.header-text h3 span {
color: #fff;
}
.btn-min-block {
min-width: 170px;
line-height: 26px;
}
.btn-theme {
color: #fff;
background-color: transparent;
border: 2px solid #fff;
margin-right: 15px;
}
.btn-theme:hover {
color: #000;
background-color: #fff;
border-color: #fff;
}
.service-box {
background: #fff;
border-bottom: 2px solid #f7f7f7;
padding: 40px 20px;
}
.service-box:hover {
-webkit-transition: all .2s ease-in-out;
-moz-transition: all .2s ease-in-out;
transition: all .2s ease-in-out;
margin-top: -20px;
}
.service-icon {
margin-bottom: 20px;
}
.service-desc h5 {
text-transform: uppercase;
font-weight: 700;
color: #666;
font-size: 18px;
margin-bottom: 10px;
}
.service-desc .divider-header {
margin-bottom: 30px;
}
.item {
margin: 10px;
}
.item img {
display: block;
width: 100%;
height: auto;
}
#contact {
background-color: #C9E4E4;
}
.form-group {
margin-bottom: 20px;
}
.btn-lg, .btn-group-lg > .btn {
border-radius: 2px;
}
.input-group-addon {
background-color: #fefefe;
border: 1px solid #eee;
}
.widget-contact {
text-align: left;
}
.boxcol-25 {
width: 100%;
}
.box-social {
list-style: none;
}
.sidebar .widget h5 {
font-size: 18px;
font-weight: 700;
margin-bottom: 20px;
text-transform: uppercase;
}
.sidebar .widget {
margin-bottom: 50px;
}
.widget ul {
list-style: none;
margin-left: 0;
padding-left: 0;
}
.sidebar .widget ul li {
margin-left: 0;
padding-left: 0;
margin-bottom: 10px;
}
.sidebar .widget ul li a {
color: #666;
}
.widget.widget_categories ul li:before {
display: inline-block;
font-family: 'Pe-icon-7-stroke';
speak: none;
font-style: normal;
font-weight: normal;
font-variant: normal;
text-transform: none;
line-height: 1;
-webkit-font-smoothing: antialiased;
-moz-osx-font-smoothing: grayscale;
content: "\e684";
margin-right: 10px;
}
.widget.widget_recent_post ul li figure {
float: left;
margin: 0 20px 0 0;
}
.widget.widget_recent_post ul li {
margin-bottom: 25px;
}
.widget.widget_recent_post ul li:after {
content: ".";
display: block;
height: 0;
clear: both;
visibility: hidden;
}
.widget.widget_recent_post ul li h6 {
margin-bottom: 10px;
}
.widget.widget_recent_post ul li span {
font-size: 14px;
}
.widget .tagcloud a {
padding: 4px 10px;
color: #fff;
display: inline-block;
margin: 0 10px 10px 0;
font-size: 14px;
border-radius: 2px;
}
.widget .tagcloud a:hover {
color: #fff;
background: #333;
}
footer {
background-image: url(http://i46.tinypic.com/2n0vdw0.jpg);
background-position: center bottom;
background-size: 100% auto;
background-repeat: repeat-x;
min-height: 50vh;
}
footer {
text-align: center;
padding: 40px 0 30px;
}
footer p {
color: #f8f8f8;
font-size: 16px;
}
footer a.totop {
color: #fff;
}
footer a.totop:focus {
outline: 0;
}
.share-button {
padding-top: 50px !important;
}
ul.footer-menu {
list-style: none;
}
ul.footer-menu li {
float: left;
margin: 0 0 0 10px;
}
ul.footer-menu li a {
color: #fff;
font-size: 16px;
padding-left: 9px;
line-height: 1.1em;
}
ul.footer-menu li:first-child a {
border-left: none;
padding-left: 0;
}
.social-widget {
margin-top: 20px;
margin-bottom: 30px;
}
.social-widget ul li a:hover {
color: #fff;
}
footer .social-widget ul.team-social li a {
margin: 0 5px;
}
.testimonialslide {
margin-top: 0;
padding-top: 0;
}
.testimonialslide ul li blockquote {
color: #fff;
border-left: none;
}
.testimonialslide ul li h4 {
color: #fff;
font-weight: 900;
}
.testimonialslide ul li h4 span {
color: #fff;
font-weight: 400;
}
.btn {
border-radius: 2px;
position: relative;
display: inline-block;
outline: none;
color: #fff;
text-decoration: none;
text-transform: uppercase;
letter-spacing: 1px;
font-weight: 400;
text-shadow: 0 0 1px rgba(255,255,255,0.3);
font-size: 14px;
}
.btn.btn-noradius {
border-radius: 0;
}
a.btn:focus {
outline: 0;
}
.btn-red {
color: #fff;
background-color: #c83539;
border-color: #c83539;
}
.btn-red:hover, .btn-red:focus, .btn-red:active, .btn-red.active {
color: #fff;
background-color: #666;
border-color: #666;
}
.btn-red:active {
background-image: none;
}
.btn-skin:hover, .btn-skin:focus, .btn-skin:active, .btn-skin.active {
color: #fff;
background-color: #666;
border-color: #666;
}
.btn-default:hover, .btn-default:focus {
border: 1px solid #28c3ab;
outline: 0;
color: #000;
background-color: #28c3ab;
}
.btn-huge {
padding: 25px;
font-size: 26px;
}
.banner-social-buttons {
margin-top: 0;
}
.progress {
height: 40px;
}
.progress-bar {
font-size: 14px;
line-height: 40px;
}
@media(min-width:767px) {
.navbar {
padding: 20px 0;
border-bottom: 0;
letter-spacing: 1px;
background: 0 0;
-webkit-transition: background .5s ease-in-out, padding .5s ease-in-out;
-moz-transition: background .5s ease-in-out, padding .5s ease-in-out;
transition: background .5s ease-in-out, padding .5s ease-in-out;
}
.top-nav-collapse {
padding: 0;
background-color: #000;
}
.navbar-custom.top-nav-collapse {
border-bottom: 1px solid rgba(255,255,255,.3);
}
.intro {
height: 100%;
padding: 0;
}
.brand-heading {
font-size: 100px;
}
.intro-text {
font-size: 25px;
}
}
@media (max-width:768px) {
#navigation {
padding: 20px 0;
}
.site-logo {
margin: 0 0 0 30px;
float: none;
}
.navbar-custom ul.nav li a {
color: #eee;
}
.navbar-custom ul.nav ul.dropdown-menu li {
border-bottom: 1px solid #aaa;
}
.navbar-header {
margin-top: -40px;
padding: 0;
}
.navbar-header button {
background: #111;
}
.navbar-header button.navbar-toggle {
padding: 4px 15px;
font-size: 14px;
color: #fff;
}
.navbar-custom .nav {
background: #444;
}
.service-box {
margin-bottom: 50px;
}
.team-wrap {
margin-bottom: 30px;
}
form#contact-form {
margin-bottom: 50px;
}
.xs-marginbot-20 {
margin-bottom: 20px;
}
}
@media (max-width:480px) {
.navbar-custom .nav.navbar-nav {
background-color: rgba(255,255,255,.4);
}
.navbar.navbar-custom.navbar-fixed-top {
margin-bottom: 30px;
}
}
.navbar .navbar-custom {
padding: 0;
}
.makina img {
width: 120px;
height: 120px;
bottom: 120px;
}
.makina-2 img {
width: 100px;
height: 100px;
bottom: 100px;
}。
答案 1 :(得分：0)
我使用的是Desktop Qt 5.10.0 MinGW 32bit。当更改为v5.8时，应用程序退出时没有错误，这对我来说已经足够了。