13、QT窗口API函数基础知识

QT窗口API函数

geometry（）

用于获取窗口在屏幕上的几何位置和大小

QRect geo = widget->geometry();
int x = geo.x(); // 窗口左上角的 x 坐标
int y = geo.y(); // 窗口左上角的 y 坐标
int w = geo.width(); // 窗口的宽度
int h = geo.height(); // 窗口的高度

width()

函数返回窗口控件的宽度

height()

函数返回窗口控件的高度

rect()

用于获取窗口控件的矩形区域。

QWidget *widget = new QWidget;
// ...
QRect r = widget->rect();
int x = r.x();      // 矩形区域左上角的 x 坐标
int y = r.y();      // 矩形区域左上角的 y 坐标
int width = r.width();   // 矩形区域的宽度
int height = r.height(); // 矩形区域的高度

例子

#include "dialog.h"
#include "ui_dialog.h"

Dialog::Dialog(QWidget *parent) :
    QDialog(parent),
    ui(new Ui::Dialog)
{
    //    ui->setupUi(this);
    resize(300,160);
    setWindowTitle("QT窗口常用的api位置函数测试");

    //布局
    glayout=new QGridLayout(this);

    labelgeometry=new QLabel("geometry()");
    labelgeometryValue=new QLabel;
    labelWidth =new QLabel("Width");
    labelWidthValue=new QLabel;
    labelHeight=new QLabel("Height");
    labelHeightValue=new QLabel;

    labelRect=new QLabel("rect");
    labelRectValue = new QLabel;

    labelSize=new QLabel("size");
    labelSizeValue = new QLabel;

    glayout->addWidget(labelgeometry,0,0);
    glayout->addWidget(labelgeometryValue,0,1);


    glayout->addWidget(labelWidth,1,0);
    glayout->addWidget(labelWidthValue,1,1);

    glayout->addWidget(labelHeight,2,0);
    glayout->addWidget(labelHeightValue,2,1);

    glayout->addWidget(labelRect,3,0);
    glayout->addWidget(labelRectValue,3,1);

    glayout->addWidget(labelSize,4,0);
    glayout->addWidget(labelSizeValue,4,1);

    UpdateLabelFunc();

}

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

void Dialog::resizeEvent(QResizeEvent *)
{
    UpdateLabelFunc();
}

void Dialog::moveEvent(QMoveEvent *)
{
    UpdateLabelFunc();
}

void Dialog::UpdateLabelFunc()
{
    QString strgeometry; //专门存放geometry()函数的显示结果

    QString str1,str2,str3,str4;


    strgeometry=str1.setNum(geometry().x())+","
            +str2.setNum(geometry().y()) + ","
            +str3.setNum(geometry().width()) + ","
            +str4.setNum(geometry().height());
    labelgeometryValue->setText(strgeometry);

    QString strw,strh;
    labelWidthValue->setText(strw.setNum(width()));
    labelHeightValue->setText(strh.setNum(height()));


    QString strrect;
    QString strrect1,strrect2,strrect3,strrect4;
    strrect=strrect1.setNum(rect().x())+","
            +strrect2.setNum(rect().y())+","
            +strrect3.setNum(rect().width())+","
            +strrect4.setNum(rect().height());
    labelRectValue->setText(strrect);


    QString strsize;
    QString strsize1,strsize2;

    strsize=strsize1.setNum(width())+","+strsize2.setNum(height());
    labelSizeValue->setText(strsize);
}