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QT学习札记-36.QTableWidget根据表格自

发布时间： 2012-08-28 12:37:01 作者： rapoo

QT学习笔记-36.QTableWidget根据表格自动调整列宽度


return model->setData(index, state, Qt::CheckStateRole);
}
void drawFocus(QPainter *painter, const QStyleOptionViewItem &option, const QRect &rect) const
{
QItemDelegate::drawFocus(painter, option, option.rect);
}
};

static int ROWS = 3;
static int COLS = 3;

class Table : public QTableWidget
{
public:
Table(QWidget *parent = 0)
: QTableWidget(ROWS, COLS, parent)
{
setItemDelegate(new ItemDelegate(this));
QTableWidgetItem *item = 0;
for(int i=0; i<rowCount(); ++i)
{
for(int j=0; j<columnCount(); ++j)
{
setItem(i, j, item = new QTableWidgetItem);
QTableViewItem;
item->setFlags(Qt::ItemIsEnabled|Qt::ItemIsUserCheckable);
item->setCheckState((i+j) % 2 == 0 ? Qt::Checked : Qt::Unchecked);
}
}
}
};

int main(int argc, char **argv)
{
QApplication a(argc, argv);
Table w;
w.show();
return a.exec();
}
posted @ 2011-11-26 11:25 ccsdu2009 阅读(264) | 评论 (0) | 编辑 收藏 QT学习笔记-31.QTableView只显示横格，不显示点击虚框的方法重新风格项代理QStyledItemDelegat

class QLineDelegate : public QStyledItemDelegate
{
Q_OBJECT
public:
QLineDelegate(QTableView* tableView);
protected:
void paint(QPainter* painter,const QStyleOptionViewItem& option,const QModelIndex& index) const;
private:
QPen pen;
QTableView* view;
};
#include <QPainter>
#include "QLineDelegate.h"

QLineDelegate::QLineDelegate(QTableView* tableView)
{
int gridHint = tableView->style()->styleHint(QStyle::SH_Table_GridLineColor, new QStyleOptionViewItemV4());
QColor gridColor = static_cast<QRgb>(gridHint);
pen = QPen(gridColor, 0, tableView->gridStyle());
view = tableView;
}

void QLineDelegate::paint(QPainter* painter, const QStyleOptionViewItem& option,const QModelIndex& index)const
{
QStyleOptionViewItem itemOption(option);
if(itemOption.state & QStyle::State_HasFocus)
itemOption.state = itemOption.state ^ QStyle::State_HasFocus;
QStyledItemDelegate::paint(painter,itemOption,index);
QPen oldPen = painter->pen();
painter->setPen(pen);
//painter->drawLine(option.rect.topRight(),option.rect.bottomRight());
painter->drawLine(itemOption.rect.bottomLeft(),itemOption.rect.bottomRight());
painter->setPen(oldPen);
}
posted @ 2011-11-25 20:22 ccsdu2009 阅读(228) | 评论 (0) | 编辑 收藏 QT学习笔记-30.QTableView只显示横格的方式默认QTableView是显示网状格子的，如果不显示网格则可以调用setShowGrid(false);来实现。但是如果只想显示横线则有点复杂了。具体代码如下:
#include <QApplication>

#include <QTableWidget>
#include <QPainter>
#include <QStyledItemDelegate>
#include <QHeaderView>
class QLineDelegate : public QStyledItemDelegate
{
public:
 QLineDelegate(QTableView* tableView);
protected:
 void paint(QPainter* painter, const QStyleOptionViewItem& option, const QModelIndex& index) const;
private:
 QPen pen;
 QTableView* view;
};
QLineDelegate::QLineDelegate(QTableView* tableView)
{
 int gridHint = tableView->style()->styleHint(QStyle::SH_Table_GridLineColor, new QStyleOptionViewItemV4());
 QColor gridColor = static_cast<QRgb>(gridHint);
 pen = QPen(gridColor, 0, tableView->gridStyle());
 view = tableView;
}
void QLineDelegate::paint(QPainter* painter, const QStyleOptionViewItem& option,const QModelIndex& index)const
{
 QStyledItemDelegate::paint(painter, option, index);
 QPen oldPen = painter->pen();
 painter->setPen(pen);
 //painter->drawLine(option.rect.topRight(), option.rect.bottomRight());
 painter->drawLine(option.rect.bottomLeft(), option.rect.bottomRight());
 painter->setPen(oldPen);
}
class QLineTableWidget:public QTableWidget
{
public:
 QLineTableWidget();
};
QLineTableWidget::QLineTableWidget()
{
 setStyleSheet("QTableView::Item{selection-background-color:#101020}");
 setStyleSheet("QTableView::Item{background-color:#F0F0F0}");
 verticalHeader()->setVisible(false);
 horizontalHeader()->setVisible(true);
 setSelectionBehavior(QAbstractItemView::SelectRows);
 setSelectionMode(QAbstractItemView::SingleSelection);
 setEditTriggers(QTableView::NoEditTriggers);
 setColumnCount(3);
 setRowCount(4);
 setShowGrid(false);
 setItemDelegate(new QLineDelegate(this));
 setCurrentCell(-1,-1);
}
int main(int argc,char **argv)
{
 QApplication a(argc,argv);
 QLineTableWidget widget;
 widget.show();
 return a.exec();
}
posted @ 2011-11-22 22:23 ccsdu2009 阅读(1253) | 评论 (0) | 编辑 收藏 QT学习笔记-30.自写的QT插件系统#ifndef QPLUGIN_SYSTEM_H
#define QPLUGIN_SYSTEM_H
#include <QObject>
#include <QVector>
#include <QPluginLoader>
#include <QDir>

template<class T>
class QPluginSystem
{
public:
void setup();
int getAddonCnt(){return addons.size();}
T* getAddonByIndex(int index){return addons.at(index);}
private:
QVector<QPluginLoader*> loaders;
QVector<T*> addons;
};

template<class T>
void QPluginSystem<T>::setup()
{
QString path = QDir::currentPath();
path += QDir::separator();
path += "addons";
QDir pluginsDir(path);

foreach(QString fileName,pluginsDir.entryList(QDir::Files))
{
bool autodel = false;
QPluginLoader* pluginLoader = new QPluginLoader(pluginsDir.absoluteFilePath(fileName));
QObject *plugin = pluginLoader->instance();
if(plugin)
{
T *interface = qobject_cast<T*>(plugin);
if(interface)
{
addons.push_back(interface);
loaders.push_back(pluginLoader);
autodel = true;
}
}

if(autodel == false)
delete pluginLoader;
}
}

#endif
其中T是插件对象，需要继承QObject
另外虽然我没试过，但是我感觉增加QPluginLoader链表是很有必要的
posted @ 2011-11-17 22:11 ccsdu2009 阅读(121) | 评论 (0) | 编辑 收藏 QT学习笔记-29.使用QT HTTP下载网络文件QT附带的例子比较好:
class HttpWindow : public QDialog
{
Q_OBJECT
public:
HttpWindow(QWidget *parent = 0);

void startRequest(QUrl url);
private slots:
void downloadFile();
void cancelDownload();
void httpFinished();
void httpReadyRead();
void updateDataReadProgress(qint64 bytesRead, qint64 totalBytes);
void enableDownloadButton();
void slotAuthenticationRequired(QNetworkReply*,QAuthenticator *);
private:
QLabel *statusLabel;
QLabel *urlLabel;
QLineEdit *urlLineEdit;
QProgressDialog *progressDialog;
QPushButton *downloadButton;
QPushButton *quitButton;
QDialogButtonBox *buttonBox;

QUrl url;
QNetworkAccessManager qnam;
QNetworkReply *reply;
QFile *file;
int httpGetId;
bool httpRequestAborted;
};其中槽有:
1.开始下载
2.取消下载
3.预备下载
4.下载完成
5.进度回调
等

实现为:
void HttpWindow::startRequest(QUrl url)
{
reply = qnam.get(QNetworkRequest(url));
connect(reply, SIGNAL(finished()),
this, SLOT(httpFinished()));
connect(reply, SIGNAL(readyRead()),
this, SLOT(httpReadyRead()));
connect(reply, SIGNAL(downloadProgress(qint64,qint64)),
this, SLOT(updateDataReadProgress(qint64,qint64)));
}该函数主要针对给定url绑定事件
void HttpWindow::downloadFile()
{
url = urlLineEdit->text();

QFileInfo fileInfo(url.path());
QString fileName = fileInfo.fileName();
fileName = "downloadfile.dat";
if(fileName.isEmpty())
fileName = "index.html";

if(QFile::exists(fileName)) {
if (QMessageBox::question(this, tr("HTTP"),
tr("There already exists a file called %1 in "
"the current directory. Overwrite?").arg(fileName),
QMessageBox::Yes|QMessageBox::No, QMessageBox::No)
== QMessageBox::No)
return;
QFile::remove(fileName);
}

file = new QFile(fileName);
if (!file->open(QIODevice::WriteOnly)) {
QMessageBox::information(this, tr("HTTP"),
tr("Unable to save the file %1: %2.")
.arg(fileName).arg(file->errorString()));
delete file;
file = 0;
return;
}

progressDialog->setWindowTitle(tr("HTTP"));
progressDialog->setLabelText(tr("Downloading %1.").arg(fileName));
downloadButton->setEnabled(false);

// schedule the request
httpRequestAborted = false;
startRequest(url);
}
当点击下载的时候，会执行该函数
获取url链接，生成本地文件，...
void HttpWindow::cancelDownload()
{
statusLabel->setText(tr("Download canceled."));
httpRequestAborted = true;
reply->abort();
downloadButton->setEnabled(true);
}终止下载，主要函数是reply->abort();
void HttpWindow::httpFinished()
{
if (httpRequestAborted) {
if (file) {
file->close();
file->remove();
delete file;
file = 0;
}
reply->deleteLater();
progressDialog->hide();
return;
}

progressDialog->hide();
file->flush();
file->close();


QVariant redirectionTarget = reply->attribute(QNetworkRequest::RedirectionTargetAttribute);
if (reply->error()) {
file->remove();
QMessageBox::information(this, tr("HTTP"),
tr("Download failed: %1.")
.arg(reply->errorString()));
downloadButton->setEnabled(true);
} else if (!redirectionTarget.isNull()) {
QUrl newUrl = url.resolved(redirectionTarget.toUrl());
if (QMessageBox::question(this, tr("HTTP"),
tr("Redirect to %1 ?").arg(newUrl.toString()),
QMessageBox::Yes | QMessageBox::No) == QMessageBox::Yes) {
url = newUrl;
reply->deleteLater();
file->open(QIODevice::WriteOnly);
file->resize(0);
startRequest(url);
return;
}
} else {
QString fileName = QFileInfo(QUrl(urlLineEdit->text()).path()).fileName();
statusLabel->setText(tr("Downloaded %1 to current directory.").arg(fileName));
downloadButton->setEnabled(true);
}

reply->deleteLater();
reply = 0;
delete file;
file = 0;
} 下载结束动作
void HttpWindow::httpReadyRead()
{
// this slot gets called every time the QNetworkReply has new data.
// We read all of its new data and write it into the file.
// That way we use less RAM than when reading it at the finished()
// signal of the QNetworkReply
if (file)
file->write(reply->readAll());
}写文件回调
void HttpWindow::updateDataReadProgress(qint64 bytesRead, qint64 totalBytes)
{
if (httpRequestAborted)
return;

progressDialog->setMaximum(totalBytes);
progressDialog->setValue(bytesRead);
}

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