控件坐标位置自适应算法

按照俺以前的做法是在gimp中算好背景图片资源的坐标及尺寸，但是这样做也不好，针对窗口的不同大小，不同的分辨率，控件就偏多很历害。

但是如果限制窗口不能调节大小，也不好，毕竟在大分辨率的屏幕屏上，客户会不满意的。

由于俺使用的是png图片，不是svg，所以放大会有失帧现在，所以俺不让它放大。

只是如果窗口大了的话，就居中显示，以前该背景图片上的所有的控件坐标都是绝对坐标，所以当窗口改变时，计算好坐标再绘制背景图片，计算方法如下：

x= (window width - background image width) /2

y=(window height - background image height) /2

这样就相当于改变了绘制背景图像时的左上角坐标，但是图像尺寸还是按照以前的，不缩放。

以前的控件坐标是绝对于背景图片的，所以现在是背景图片偏移了坐标，

故对于控件的定位可以在resizeEvent()事件中，对控件坐标重新定位即可。

它的最新的绝对坐标计算方法是

绝对坐标+偏移量。

偏移量应该使用背景图片的偏移量。

若以前为

this->m_lineEditOut->setGeometry(62,81,31,10);

则现在应该变为

qint32 tOffsetX=(this->size().width()-this->m_backgroundPixmap.width())/2;

qint32 tOffsetY=(this->size().height()-this->m_backgroundPixmap.height())/2;

this->m_lineEditOut->setGeometry(62+tOffsetX,81+tOffsetY,31,10);

以下为试验的效果图：







可以看到，不管窗口如何缩放，那显示数字的4个文本框都是那么听话的被放置的合适的位置上。

老规矩，贡献出代码：

#ifndef WIDGET_H

#define WIDGET_H

#include <QWidget>

#include <QPaintEvent>

#include <QLineEdit>

#include <QTimer>

class Widget : public QWidget

{

Q_OBJECT

public:

Widget(QWidget *parent = 0);

~Widget();

protected:

void paintEvent(QPaintEvent *event);

void resizeEvent(QResizeEvent *event);

private slots:

void updateTemperature();

private:

QLineEdit *m_lineEditOut;

QLineEdit *m_lineEditIn;

QLineEdit *m_lineEditMix;

QLineEdit *m_lineEditCheck;

QTimer *m_timer;

QPixmap m_backgroundPixmap;

};

#endif // WIDGET_H

#include "widget.h"

#include <QPaintEvent>

#include <QPainter>

Widget::Widget(QWidget *parent)

: QWidget(parent)

{

QFont tFont=this->font();

tFont.setPixelSize(10);

this->setFont(tFont);

this->m_backgroundPixmap.load(":/background.png");

this->m_lineEditOut=new QLineEdit(this);

this->m_lineEditOut->setGeometry(62,81,31,10);

this->m_lineEditOut->setAlignment(Qt::AlignCenter);

this->m_lineEditOut->setStyleSheet(QString("QLineEdit{border:0px}"));

this->m_lineEditIn=new QLineEdit(this);

this->m_lineEditIn->setGeometry(222,81,31,10);

this->m_lineEditIn->setAlignment(Qt::AlignCenter);

this->m_lineEditIn->setStyleSheet(QString("QLineEdit{border:0px}"));

this->m_lineEditMix=new QLineEdit(this);

this->m_lineEditMix->setGeometry(142,234,31,10);

this->m_lineEditMix->setAlignment(Qt::AlignCenter);

this->m_lineEditMix->setStyleSheet(QString("QLineEdit{border:0px}"));

this->m_lineEditCheck=new QLineEdit(this);

this->m_lineEditCheck->setGeometry(36,319,31,10);

this->m_lineEditCheck->setAlignment(Qt::AlignCenter);

this->m_lineEditCheck->setStyleSheet(QString("QLineEdit{border:0px}"));

this->m_timer=new QTimer;

this->m_timer->setInterval(500);

connect(this->m_timer,SIGNAL(timeout()),this,SLOT(updateTemperature()));

this->m_timer->start();

}

Widget::~Widget()

{

delete this->m_lineEditIn;

delete this->m_lineEditOut;

delete this->m_lineEditMix;

delete this->m_lineEditCheck;

delete this->m_timer;

}

void Widget::paintEvent(QPaintEvent *event)

{

QPainter tPainter(this);

QRect tBack(0,0,this->size().width(),this->size().height());

tPainter.fillRect(tBack,Qt::white);

qint32 tX=(this->size().width()-this->m_backgroundPixmap.width())/2;

qint32 tY=(this->size().height()-this->m_backgroundPixmap.height())/2;

tPainter.drawPixmap(tX,tY,this->m_backgroundPixmap.width(),this->m_backgroundPixmap.height(),this->m_backgroundPixmap);

}

void Widget::resizeEvent(QResizeEvent *event)

{

qint32 tOffsetX=(this->size().width()-this->m_backgroundPixmap.width())/2;

qint32 tOffsetY=(this->size().height()-this->m_backgroundPixmap.height())/2;

this->m_lineEditOut->setGeometry(62+tOffsetX,81+tOffsetY,31,10);

this->m_lineEditIn->setGeometry(222+tOffsetX,81+tOffsetY,31,10);

this->m_lineEditMix->setGeometry(142+tOffsetX,234+tOffsetY,31,10);

this->m_lineEditCheck->setGeometry(36+tOffsetX,319+tOffsetY,31,10);

}

void Widget::updateTemperature()

{

qsrand(time(NULL));

int nOut = qrand()%20;

int nIn = qrand()%20;

int nMix = qrand()%20;

int nCheck = qrand()%100;

this->m_lineEditOut->setText(QString("%1").arg(nOut));

this->m_lineEditIn->setText(QString("%1").arg(nIn));

this->m_lineEditMix->setText(QString("%1").arg(nMix));

this->m_lineEditCheck->setText(QString("%1").arg(nCheck));

}