ui.Display_3->setPixmap(*iserialPic);中setPixmap

`setPixmap(const QPixmap &)` 是 `QLabel` 类的一个函数，用于在标签中显示一个 `QPixmap` 对象。`QPixmap` 是 Qt 框架中的一个类，用于处理图片。在你的示例中，`ui.Display_3` 是一个 `QLabel` 对象，`setPixmap(*iserialPic)` 表示将一个 `QPixmap` 对象指针 `iserialPic` 指向的图片设置为 `ui.Display_3` 标签中的显示内容。这样就可以在标签中显示图片了。

相关问题

QT改错，#include "widget.h" #include "ui_widget.h" #include <QTime> #include <QTimer> #include <QPixmap> #include <iostream> #include <string> #include <QDebug> Widget::Widget(QWidget *parent) : QWidget(parent) , ui(new Ui::Widget) { ui->setupUi(this); this->count = 0; this->tm = new QTimer(this); this->tm->start(1000); this->ui->label_2->setText(QTime::currentTime().toString("yyyy-MM-dd hh:mm:ss")); QTime time(0,0,0,0); this->ui->timeNumber->display(time.toString("hh:mm:ss")); //初始化label QPixmap pic(":/images/1.ipg"); this->ui->label->setPixmap(pic); for (int i = 1; i <= 9; i ++){ QString file_path = ":/images/"; file_path = QString::number(i) + ".jpg"; ph_set.push_back(file_path); qDebug() << file_path << endl; } connect(this->tm,&QTimer::timeout,this,&Widget::update_tm); } Widget::~Widget() { delete ui; } void Widget::update_tm() { this->count ++; QTime time(0,0,0,0); this->ui->timeNumber->display(time.addSecs(count).toString("mm:ss")); this->ui->label_2->setText(QTime::currentTime().toString("hh:mm:ss")); } void Widget::on_beforeButton_clicked() { } void Widget::on_afterButton_clicked() { }

代码中的图片路径有误，应该将第13行的 "ipg" 改为 "jpg"。正确的代码如下：

#include "widget.h"
#include "ui_widget.h"
#include <QTime>
#include <QTimer>
#include <QPixmap>
#include <iostream>
#include <string>
#include <QDebug>

Widget::Widget(QWidget *parent)
    : QWidget(parent)
    , ui(new Ui::Widget)
{
    ui->setupUi(this);
    this->count = 0;
    this->tm = new QTimer(this);
    this->tm->start(1000);
    this->ui->label_2->setText(QTime::currentTime().toString("yyyy-MM-dd hh:mm:ss"));
    QTime time(0,0,0,0);
    this->ui->timeNumber->display(time.toString("hh:mm:ss"));
    //初始化label
    QPixmap pic(":/images/1.jpg");
    this->ui->label->setPixmap(pic);
    for (int i = 1; i <= 9; i ++){
        QString file_path = ":/images/";
        file_path = QString::number(i) + ".jpg";
        ph_set.push_back(file_path);
        qDebug() << file_path << endl;
    }
    connect(this->tm,&QTimer::timeout,this,&Widget::update_tm);
}

Widget::~Widget()
{
    delete ui;
}

void Widget::update_tm()
{
    this->count ++;
    QTime time(0,0,0,0);
    this->ui->timeNumber->display(time.addSecs(count).toString("mm:ss"));
    this->ui->label_2->setText(QTime::currentTime().toString("hh:mm:ss"));
}

void Widget::on_beforeButton_clicked()
{
}

void Widget::on_afterButton_clicked()
{
}

void MainWindow::noAgreeWithData(){ int64 currentime=QDateTime::currentMSecsSinceEpoch(); //&& !this->ui->nopass->isChecked() if(ui->tableWidget->rowCount()>0 && currentime-firstTriggerTime<25000){ QLabel *qlable=new QLabel(ui->frame); QPixmap pixmap(":/image/nopass.png"); pixmap.setDevicePixelRatio(3); // 设置缩放比例，如果需要的话 QPainter painter(&pixmap); painter.setOpacity(0.7); // 设置透明度为50% painter.drawPixmap(0, 0, pixmap); painter.end(); qlable->setPixmap(pixmap); qlable->setAlignment(Qt::AlignHCenter | Qt::AlignVCenter); qDebug()<<"ui->frame->size()"<<ui->frame->size(); QSize size(550,550); //qlable->setMargin(200); qlable->setGeometry(600, 100, 550, 550); qlable->setFixedSize(size); qlable->setAttribute(Qt::WA_DeleteOnClose); qlable->show(); this->ui->nopass->setChecked(true); sec =25; verifyGoods->stop(); ui->goodsLabel->hide(); ui->goodsNumber->display(sec); ui->goodsNumber->hide(); QString msg=settings->value("voiceprompt/the_actual_items_carried_do_not_match_the_exit_slip_msg","实际携带物品与出门条不相符").toString(); QVariantMap map; instantGateToMap(map); //非法闯入 this->trespassing(map,7,PlayToSpeech::THE_ACTUAL_ITEMS_CARRIED_DO_NOT_MATCH_THE_EXIT_SLIP); this->unlawfuldialog(msg); } }如何在noAgreeWithData结束释放内存*qlable?

在`noAgreeWithData()`函数结束后释放`qlable`的内存，你可以使用`delete`操作符来释放它。同时，你还可以将`qlable`设置为父对象，这样当父对象销毁时，它也会自动销毁。

以下是修改后的代码：

void MainWindow::noAgreeWithData() {
    int64 currentime = QDateTime::currentMSecsSinceEpoch();
    //&& !this->ui->nopass->isChecked()
    if (ui->tableWidget->rowCount() > 0 && currentime - firstTriggerTime < 25000) {
        QLabel* qlable = new QLabel(ui->frame);
        // ... 其他代码 ...

        qlable->setPixmap(pixmap);
        qlable->setAlignment(Qt::AlignHCenter | Qt::AlignVCenter);
        qDebug() << "ui->frame->size()" << ui->frame->size();

        QSize size(550, 550);
        qlable->setGeometry(600, 100, 550, 550);
        qlable->setFixedSize(size);
        qlable->setAttribute(Qt::WA_DeleteOnClose);
        qlable->show();

        // 设置qlable的父对象为ui->frame
        qlable->setParent(ui->frame);

        // ... 其他代码 ...
    }
}

通过将`ui->frame`作为`qlable`的父对象，当`ui->frame`销毁时，它会自动删除其所有子对象，包括`qlable`。

请确保在适当的时机删除指针以避免内存泄漏。