aaa云主机可以建网站吗,谷歌云宝塔搭建WordPress,网页设计实训总结3000字大学篇,网页qq登陆网站本文实现的目的是#xff1a;视图缩放时#xff0c;缩略图中的矩形框也进行缩放#xff0c;而缩略图中的矩形区域为视图中的可见区。 获取视图中滚动条的值#xff0c;将其值与缩略图所在的小窗口对比#xff0c;可通过绘图求其比例#xff0c;再按比例缩小。 首先提供主…本文实现的目的是视图缩放时缩略图中的矩形框也进行缩放而缩略图中的矩形区域为视图中的可见区。 获取视图中滚动条的值将其值与缩略图所在的小窗口对比可通过绘图求其比例再按比例缩小。 首先提供主要的代码
connect(view-verticalScrollBar(),QScrollBar::valueChanged,this,chunzhongForm::slot_VvalueChanged);
connect(view-horizontalScrollBar(),QScrollBar::valueChanged,this,chunzhongForm::slot_HvalueChanged);void chunzhongForm::slot_VvalueChanged(int value)
{if(value ! 0 dlg ! NULL){m_y value;if(dlg-isVisible()){emit signalSetDrawRectSize();}}
}void chunzhongForm::slot_HvalueChanged(int value)
{if(value ! 0 dlg ! NULL){m_x value;if(dlg-isVisible()){emit signalSetDrawRectSize();}}
}connect(this,chunzhongForm::signalSetDrawRectSize,this,chunzhongForm::slot_setViewRect);QSize GraphicsView::viewportSizeHint()
{return viewport()-size();
}void chunzhongForm::slot_setViewRect()
{m_viewSize view-viewportSizeHint();//获取视口大小int x m_x / (m_viewSize.width() * m_scale)* SMALL_W;int y m_y / (m_viewSize.height() * m_scale)* SMALL_H;int wid SMALL_W / m_scale;int hei SMALL_H / m_scale;outPut小矩形坐标及大小(m_x ,m_y ,wid ,hei);//换成qDebug输出QRect rect(x,y,wid,hei);emit signalDrawRect(rect);
}
connect(this,chunzhongForm::signalDrawRect,dlg,BreviaryDlg::slot_setRectSize);//缩略图窗口类BreviaryDlg
void BreviaryDlg::slot_setRectSize(QRect rect)
{m_rect rect;scene-onSetPreviewRect(rect);
}//缩略图中的自定义场景
void MyGraphicsScene::onSetPreviewRect(QRect rect)
{m_rectSaved rect;// 内缩几个像素用矩形外边框来标示viewport显示区域m_pRectItem-setRect(rect.x() - 2/* 5*/, rect.y() - 2/* 5*/, rect.width() - 4, rect.height() - 4);//设置图形项矩形
}下面贴出自定义场景类 MyGraphicsScene.h
#pragma once//#include vld.h
#include QGraphicsSceneclass MyGraphicsScene : public QGraphicsScene
{Q_OBJECTpublic:MyGraphicsScene(QObject *parent nullptr);virtual void mouseMoveEvent(QGraphicsSceneMouseEvent *mouseEvent);virtual void mousePressEvent(QGraphicsSceneMouseEvent *mouseEvent);virtual void mouseReleaseEvent(QGraphicsSceneMouseEvent *mouseEvent);Q_SIGNALS:void previewRectMoved(QRect rect);public Q_SLOTS:void onSetPreviewRect(QRect rect);private:QGraphicsRectItem* m_pRectItem;QRect m_rectSaved;bool m_bRectClicked;QPoint m_ptRectRelated; // 鼠标点击时相对于红色矩形框的位置
};MyGraphicsScene.cpp
#include MyGraphicsScene.h
#include QGraphicsSceneMouseEvent
#include QGraphicsRectItem
#include QDebugMyGraphicsScene::MyGraphicsScene(QObject *parent): QGraphicsScene(parent), m_bRectClicked(false)
{m_pRectItem new QGraphicsRectItem(0, 0, 0, 0);QPen penRectItem QPen(QColor(255, 0, 0));penRectItem.setWidth(2);m_pRectItem-setPen(penRectItem);m_pRectItem-setZValue(1);addItem(m_pRectItem);
}void MyGraphicsScene::onSetPreviewRect(QRect rect)
{m_rectSaved rect;// 内缩几个像素用矩形外边框来标示viewport显示区域m_pRectItem-setRect(rect.x() - 2/* 5*/, rect.y() - 2/* 5*/, rect.width() - 4, rect.height() - 4);
}void MyGraphicsScene::mouseMoveEvent(QGraphicsSceneMouseEvent *mouseEvent)
{QGraphicsScene::mouseMoveEvent(mouseEvent);if (m_bRectClicked) {QPoint ptTopLeft mouseEvent-scenePos().toPoint() - m_ptRectRelated;m_rectSaved.setTopLeft(ptTopLeft);
// qDebug()mouseMoveEvent;emit previewRectMoved(m_rectSaved);}
}void MyGraphicsScene::mousePressEvent(QGraphicsSceneMouseEvent *mouseEvent)
{QGraphicsScene::mousePressEvent(mouseEvent);if (m_rectSaved.contains(mouseEvent-scenePos().x(), mouseEvent-scenePos().y())) {m_bRectClicked true;m_ptRectRelated mouseEvent-scenePos().toPoint() - m_rectSaved.topLeft();}
}void MyGraphicsScene::mouseReleaseEvent(QGraphicsSceneMouseEvent *mouseEvent)
{QGraphicsScene::mouseReleaseEvent(mouseEvent);m_bRectClicked false;
}
