环境配置 :MinGW + QT 5.12 |
这里需要说明一下:QListWidget是鼠标press时item就会被选中,自定义的TestListWidget类重写了mousePressEvent和mouseReleaseEvent使得item在鼠标release时才会被选中。至于为什么这样做,是因为Chrome浏览器的书签栏以及网易云音乐的选项列表都是在鼠标release时才会触发选中…
本文中实现方法:
另一种实现方法:自定义QListWidget实现item被hover时改变图标样式(模仿网易云音乐选项列表)(方法一)
(1)TestListWidgetItem类继承自QListWidgetItem
class TestListWidgetItem : public QListWidgetItem
{
//Q_OBJECT //由于QListWidgetItem没有QObject属性,所以Q_OBJECT需要注释掉
public:
explicit TestListWidgetItem(QListWidget *view = nullptr);
void setUpIcon(const QIcon &icon, const QIcon &icon_hover);
QIcon Img;
QIcon Img_hover;
};
TestListWidgetItem::TestListWidgetItem(QListWidget *view) :
QListWidgetItem(view)
{
}
void TestListWidgetItem::setUpIcon(const QIcon &icon, const QIcon &icon_hover)
{
Img = icon;
Img_hover = icon_hover;
setIcon(Img);
}
(2)TestListWidget类继承自QListWidget
class TestListWidget : public QListWidget
{
Q_OBJECT
public:
explicit TestListWidget(QWidget *parent = nullptr);
protected:
void mousePressEvent(QMouseEvent *event) override;
void mouseReleaseEvent(QMouseEvent *event) override;
private:
QPoint startPos;
};
TestListWidget::TestListWidget(QWidget *parent) :
QListWidget(parent)
{
}
//鼠标按下时,startPos记录单击位置
void TestListWidget::mousePressEvent(QMouseEvent *event)
{
if(event->buttons() & Qt::LeftButton){
startPos = event->pos();
}
}
//释放鼠标时,item才会被选中
void TestListWidget::mouseReleaseEvent(QMouseEvent *event)
{
//如果鼠标释放位置和单击位置相距超过5像素,则不会触发item选中
if((event->pos() - startPos).manhattanLength() > 5) return;
TestListWidgetItem *item = static_cast<TestListWidgetItem *>(itemAt(event->pos()));
setCurrentItem(item);
}
(3)TestItemDelegate类继承自QStyledItemDelegate
class TestItemDelegate : public QStyledItemDelegate
{
Q_OBJECT
public:
TestItemDelegate(QObject *parent = nullptr);
protected:
void paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const;
};
void TestItemDelegate::paint(QPainter * painter, const QStyleOptionViewItem & option, const QModelIndex & index) const
{
TestListWidget *listWidget = qobject_cast<TestListWidget *>(option.styleObject);
QRect rect = option.rect;
painter->setRenderHint(QPainter::Antialiasing, true);
painter->setPen(Qt::NoPen);
if(option.state & (QStyle::State_MouseOver | QStyle::State_Selected)){
TestListWidgetItem *item = static_cast<TestListWidgetItem *>(listWidget->item(index.row()));
item->setIcon(item->Img_hover);
if(option.state & QStyle::State_MouseOver){
}
if(option.state & QStyle::State_Selected){
painter->setBrush(QColor(180, 0, 0));
painter->drawRect(rect.topLeft().x(), rect.topLeft().y(), 4, rect.height());
painter->setBrush(QColor(230, 231, 234));
painter->drawRect(rect.topLeft().x() + 4, rect.topLeft().y(), rect.width() - 4, rect.height());
}
}else{
TestListWidgetItem *item = static_cast<TestListWidgetItem *>(listWidget->item(index.row()));
item->setIcon(item->Img);
}
QStyledItemDelegate::paint(painter, option, index);
}
(4)使用TestListWidget、TestListWidgetItem以及TestItemDelegate
void test::initUi()
{
setFixedSize(250, 600);
TestListWidget *listwidget = new TestListWidget(this);
listwidget->setIconSize(QSize(25, 25));
listwidget->setFocusPolicy(Qt::NoFocus); //这样可禁用tab键和上下方向键并且除去复选框
listwidget->setFixedHeight(320);
listwidget->setFont(QFont("宋体", 10, QFont::DemiBold));
listwidget->setStyleSheet(
//"*{outline:0px;}" //除去复选框
"QListWidget{background:rgb(245, 245, 247); border:0px; margin:0px 0px 0px 0px;}"
"QListWidget::Item{height:40px; border:0px; padding-left:14px; color:rgba(200, 40, 40, 255);}"
"QListWidget::Item:hover{color:rgba(40, 40, 200, 255); padding-left:14px;}"
"QListWidget::Item:selected{color:rgba(40, 40, 200, 255); padding-left:15px;}"
//"QListWidget::Item:selected:active{/*color:rgba(40, 40, 200, 255);*/ padding-left:14px;}"
);
TestItemDelegate *delegate = new TestItemDelegate();
listwidget->setItemDelegate(delegate);
TestListWidgetItem *item1 = new TestListWidgetItem(listwidget);
item1->setUpIcon(QIcon(":/listBar_Icon/1.png"), QIcon(":/listBar_Icon/1_hover.png"));
item1->setText("发现音乐");
TestListWidgetItem *item2 = new TestListWidgetItem(listwidget);
item2->setUpIcon(QIcon(":/listBar_Icon/2.png"), QIcon(":/listBar_Icon/2_hover.png"));
item2->setText("私人FM");
TestListWidgetItem *item3 = new TestListWidgetItem(listwidget);
item3->setUpIcon(QIcon(":/listBar_Icon/3.png"), QIcon(":/listBar_Icon/3_hover.png"));
item3->setText("朋友");
TestListWidgetItem *item4 = new TestListWidgetItem(listwidget);
item4->setUpIcon(QIcon(":/listBar_Icon/4.png"), QIcon(":/listBar_Icon/4_hover.png"));
item4->setText("MV");
TestListWidgetItem *item5 = new TestListWidgetItem(listwidget);
item5->setUpIcon(QIcon(":/listBar_Icon/5.png"), QIcon(":/listBar_Icon/5_hover.png"));
item5->setText("本地音乐");
TestListWidgetItem *item6 = new TestListWidgetItem(listwidget);
item6->setUpIcon(QIcon(":/listBar_Icon/6.png"), QIcon(":/listBar_Icon/6_hover.png"));
item6->setText("下载管理");
TestListWidgetItem *item7 = new TestListWidgetItem(listwidget);
item7->setUpIcon(QIcon(":/listBar_Icon/7.png"), QIcon(":/listBar_Icon/7_hover.png"));
item7->setText("我的音乐云盘");
TestListWidgetItem *item8 = new TestListWidgetItem(listwidget);
item8->setUpIcon(QIcon(":/listBar_Icon/8.png"), QIcon(":/listBar_Icon/8_hover.png"));
item8->setText("我的收藏");
QVBoxLayout *layout = new QVBoxLayout(this);
layout->setSpacing(0);
layout->addWidget(listwidget);
layout->setContentsMargins(0, 0, 0, 0);
setLayout(layout);
}
环境配置 :MinGW + QT 5.12 |