自定义QTableWidget实现分页。

#include "PageWidget.h" #include "ui_PageWidget.h" #include <QtGlobal> #include <QHBoxLayout> #include <QMouseEvent> #include <QKeyEvent> #include <QDebug> #pragma execution_character_set("utf-8") PageWidget::PageWidget(int blockSize, QWidget *parent) : QWidget(parent), ui(new Ui::PageWidget) { ui->setupUi(this); setBlockSize(blockSize); initialize(); maxPage = 0; itemCount = 0; setMaxPage(10); } PageWidget::~PageWidget() { delete ui; delete pageLabels; } void PageWidget::setItemCount(int count) { itemCount = count; updatePageLabels(); } bool PageWidget::eventFilter(QObject *watched, QEvent *e) { if (e->type() == QEvent::MouseButtonRelease) { int page = -1; if (watched == ui->previousPageLabel) { page = getCurrentPage() - 1; } if (watched == ui->nextPageLabel) { page = getCurrentPage() + 1; } for (int i = 0; i < pageLabels->count(); ++i) { if (watched == pageLabels->at(i)) { page = pageLabels->at(i)->text().toInt(); break; } } if (-1 != page) { setCurrentPage(page, true); return true; } } if (watched == ui->pageLineEdit && e->type() == QEvent::KeyRelease) { QKeyEvent *ke = static_cast<QKeyEvent *>(e); if (ke->key() == Qt::Key_Enter || ke->key() == Qt::Key_Return) { setCurrentPage(ui->pageLineEdit->text().toInt(), true); return true; } } return QWidget::eventFilter(watched, e); } int PageWidget::getBlockSize() const { return blockSize; } int PageWidget::getMaxPage() const { return maxPage; } int PageWidget::getCurrentPage() const { return currentPage; } void PageWidget::setMaxPage(int page) { page = qMax(page, 1); if (maxPage != page) { this->maxPage = page; this->currentPage = 1; updatePageLabels(); } } void PageWidget::setCurrentPage(int page, bool signalEmitted) { page = qMax(page, 1); page = qMin(page, maxPage); if (page != this->currentPage) { this->currentPage = page; updatePageLabels(); if (signalEmitted) { emit currentPageChanged(page); } } } void PageWidget::setBlockSize(int blockSize) { // 为了便于计算, block size 必须是奇数, 且最小为3 blockSize = qMax(blockSize, 3); if (blockSize % 2 == 0) { ++blockSize; } this->blockSize = blockSize; } // 初始化页码的labels // 分成三个部分, 左...中...右 void PageWidget::initialize() { ui->pageLineEdit->installEventFilter(this); ui->pageLineEdit->setValidator(new QIntValidator(1, 10000000, this)); ui->nextPageLabel->setProperty("page", "true"); ui->previousPageLabel->setProperty("page", "true"); ui->nextPageLabel->installEventFilter(this); ui->previousPageLabel->installEventFilter(this); pageLabels = new QList<QLabel *>(); QHBoxLayout *leftLayout = new QHBoxLayout(); QHBoxLayout *centerLayout = new QHBoxLayout(); QHBoxLayout *rightLayout = new QHBoxLayout(); leftLayout->setContentsMargins(0, 0, 0, 0); leftLayout->setSpacing(0); centerLayout->setContentsMargins(0, 0, 0, 0); centerLayout->setSpacing(0); rightLayout->setContentsMargins(0, 0, 0, 0); rightLayout->setSpacing(0); for (int i = 0; i < blockSize * 3; ++i) { QLabel *label = new QLabel(QString::number(i + 1)); label->setProperty("page", "true"); label->installEventFilter(this); pageLabels->append(label); if (i < blockSize) { leftLayout->addWidget(label); } else if (i < blockSize * 2) { centerLayout->addWidget(label); } else { rightLayout->addWidget(label); } } ui->leftPagesWidget->setLayout(leftLayout); ui->centerPagesWidget->setLayout(centerLayout); ui->rightPagesWidget->setLayout(rightLayout); ui->comboBox_MaxPage->insertItem(0,"10条/页"); ui->comboBox_MaxPage->insertItem(1,"20条/页"); ui->comboBox_MaxPage->insertItem(2,"30条/页"); ui->comboBox_MaxPage->insertItem(3,"40条/页"); } void PageWidget::updatePageLabels() { ui->leftSeparateLabel->hide(); ui->rightSeparateLabel->hide(); int pageSize = itemCount % maxPage > 0 ? (itemCount / maxPage) + 1 : (itemCount / maxPage); if (pageSize <= blockSize * 3) { for (int i = 0; i < pageLabels->count(); i += 1) { QLabel *label = pageLabels->at(i); if (i < pageSize) { label->setText(QString::number(i + 1)); label->show(); } else { label->hide(); } if (currentPage - 1 == i) { label->setProperty("currentPage", "true"); } else { label->setProperty("currentPage", "false"); } label->setStyleSheet("/**/"); } return; } // 以下情况为maxPageNumber大于blockSize * 3, 所有的页码label都要显示 // c 为 currentPage // n 为 block size // m 为 maxPage // 1. c ∈ [1, n + n/2 + 1]: 显示前 n * 2 个, 后 n 个: 只显示右边的分隔符 // 2. c ∈ [m - n - n/2, m]: 显示前 n 个, 后 n * 2 个: 只显示左边的分隔符 // 3. 显示[1, n], [c - n/2, c + n/2], [m - 2*n + 1, m]: 两个分隔符都显示 int c = currentPage; int n = blockSize; int m = pageSize; int centerStartPage = 0; if (c >= 1 && c <= n + n / 2 + 1) { // 1. c ∈ [1, n + n/2 + 1]: 显示前 n * 2 个, 后 n 个: 只显示右边的分隔符 centerStartPage = n + 1; ui->rightSeparateLabel->show(); } else if (c >= m - n - n / 2 && c <= m) { // 2. c ∈ [m - n - n/2, m]: 显示前 n 个, 后 n * 2 个: 只显示左边的分隔符 centerStartPage = m - n - n + 1; ui->leftSeparateLabel->show(); } else { // 3. 显示[1, n], [c - n/2, c + n/2], [m - n + 1, m]: 两个分隔符都显示 centerStartPage = c - n / 2; ui->rightSeparateLabel->show(); ui->leftSeparateLabel->show(); } for (int i = 0; i < n; ++i) { pageLabels->at(i)->setText(QString::number(i + 1)); // 前面 n 个 pageLabels->at(n + i)->setText(QString::number(centerStartPage + i)); // 中间 n 个 pageLabels->at(3 * n - i - 1)->setText(QString::number(m - i)); // 后面 n 个 } for (int i = 0; i < pageLabels->count(); ++i) { QLabel *label = pageLabels->at(i); int page = label->text().toInt(); if (page == currentPage) { label->setProperty("currentPage", "true"); } else { label->setProperty("currentPage", "false"); } label->setStyleSheet("/**/"); label->show(); } } void PageWidget::on_comboBox_MaxPage_currentIndexChanged(int index) { switch (index) { case 0: setMaxPage(10); break; case 1: setMaxPage(20); break; case 2: setMaxPage(30); break; case 3: setMaxPage(40); break; default: setMaxPage(5); break; } emit currentPageChanged(this->currentPage); }