PushMe is fun elusive button

1-ReadMe.md

Warning!

This gist was moved to:

https://github.com/EXL/Stuff/tree/master/Examples/Qt-PushMe

demonstration.gif

main.cpp

#include "Widget.h"

#include <QApplication>
#include <QTranslator>
#include <QLocale>

#include <ctime>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);

    qsrand(time(0));

    QTranslator appTranslator;
    appTranslator.load("PushMe_" + QLocale::system().name(), "://");
    a.installTranslator(&appTranslator);

    Widget w;
    w.show();

    return a.exec();
}

PushMe.pro

#-------------------------------------------------
#
# Project created by QtCreator 2014-07-29T21:37:03
#
#-------------------------------------------------

QT       += core gui

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = PushMe
TEMPLATE = app


SOURCES += main.cpp\
        Widget.cpp

HEADERS  += Widget.h

FORMS    += Widget.ui

TRANSLATIONS += PushMe_en.ts \
            PushMe_ru.ts \
            PushMe_es.ts

RESOURCES += \
    PushMe.qrc

PushMe.qrc

<RCC>
    <qresource prefix="/">
        <file>PushMe_es.qm</file>
        <file>PushMe_ru.qm</file>
        <file>PushMe_en.qm</file>
    </qresource>
</RCC>

PushMe_en.qm

PushMe_en.ts

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE TS>
<TS version="2.1" language="en_US">
<context>
    <name>Widget</name>
    <message>
        <location filename="Widget.ui" line="14"/>
        <location filename="Widget.ui" line="26"/>
        <source>Push Me!</source>
        <translation>Push Me!</translation>
    </message>
    <message>
        <location filename="Widget.cpp" line="101"/>
        <source>Win!</source>
        <translation>Win!</translation>
    </message>
    <message>
        <location filename="Widget.cpp" line="101"/>
        <source>Oh Yeah! You win!</source>
        <translation>Oh Yeah! You win!</translation>
    </message>
</context>
</TS>

PushMe_es.qm

PushMe_es.ts

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE TS>
<TS version="2.1" language="es_ES">
<context>
    <name>Widget</name>
    <message>
        <location filename="Widget.ui" line="14"/>
        <location filename="Widget.ui" line="26"/>
        <source>Push Me!</source>
        <translation>Push Me!</translation>
    </message>
    <message>
        <location filename="Widget.cpp" line="101"/>
        <source>Win!</source>
        <translation>¡Victoria!</translation>
    </message>
    <message>
        <location filename="Widget.cpp" line="101"/>
        <source>Oh Yeah! You win!</source>
        <translation>Oh sí! Usted gana!</translation>
    </message>
</context>
</TS>

PushMe_ru.qm

PushMe_ru.ts

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE TS>
<TS version="2.1" language="ru_RU">
<context>
    <name>Widget</name>
    <message>
        <location filename="Widget.ui" line="14"/>
        <location filename="Widget.ui" line="26"/>
        <source>Push Me!</source>
        <translation>Нажми меня!</translation>
    </message>
    <message>
        <location filename="Widget.cpp" line="101"/>
        <source>Win!</source>
        <translation>Победа!</translation>
    </message>
    <message>
        <location filename="Widget.cpp" line="101"/>
        <source>Oh Yeah! You win!</source>
        <translation>О да! Вы выиграли!</translation>
    </message>
</context>
</TS>

Widget.cpp

#include "Widget.h"
#include "ui_Widget.h"

#include <QCursor>
#include <QMessageBox>

Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    ui->setupUi(this);

    ui->pushButton->installEventFilter(this);

    startTimer(10);
}

void Widget::timerEvent(QTimerEvent *)
{
    if (buttonCoords().contains(QCursor::pos())) {
        moveButton();
    }
}

bool Widget::eventFilter(QObject *obj, QEvent *event)
{
    if (obj == ui->pushButton) {
        if (event->type() == QEvent::KeyPress) {
            return true;
        }
    }

    return QWidget::eventFilter(obj, event);
}

QRect Widget::buttonCoords() const
{
    QPoint globalCoords = ui->pushButton->mapToGlobal(QPoint(0,0));

    int x = globalCoords.x();
    int y = globalCoords.y();

    QPoint lastCorner;
    lastCorner.setX(x + ui->pushButton->width());
    lastCorner.setY(y + ui->pushButton->height());

    return QRect(globalCoords, lastCorner);
}

void Widget::moveButton()
{
    ui->pushButton->move(generateValidPoint());
}

QPoint Widget::generateValidPoint() const
{
    int eps = 5;

    int x = ui->pushButton->pos().x();
    int y = ui->pushButton->pos().y();

    if (buttonCoords().center().x() < QCursor::pos().x()) {
        x = qrand() % eps - ui->pushButton->width() / 4 + ui->pushButton->pos().x();
    }

    if (buttonCoords().center().y() < QCursor::pos().y()) {
        y = qrand() % eps - ui->pushButton->height() / 2 + ui->pushButton->pos().y();
    }

    if (buttonCoords().center().x() >= QCursor::pos().x()) {
        x = qrand() % eps + ui->pushButton->width() / 4 + ui->pushButton->pos().x();
    }

    if (buttonCoords().center().y() >= QCursor::pos().y()) {
        y = qrand() % eps + ui->pushButton->height() / 2 + ui->pushButton->pos().y();
    }

    if (!rect().contains(QRect(x, y, ui->pushButton->width(), ui->pushButton->height()))) {
        if (rect().x() < x) {
            x = qrand() % eps - ui->pushButton->width() / 4 + ui->pushButton->pos().x();
        }

        if (rect().y() < y) {
            y = qrand() % eps - ui->pushButton->height() / 2 + ui->pushButton->pos().y();
        }

        if (rect().x() >= x) {
            x = qrand() % eps + ui->pushButton->width() / 4 + ui->pushButton->pos().x();
        }

        if (rect().y() >= y) {
            y = qrand() % eps + ui->pushButton->height() / 2 + ui->pushButton->pos().y();
        }
    }

    return QPoint(x, y);
}

void Widget::on_pushButton_clicked()
{
    QMessageBox::information(this, tr("Win!"), tr("Oh Yeah! You win!"));
}

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

Widget.h

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>

namespace Ui {
class Widget;
}

class Widget : public QWidget
{
    Q_OBJECT
private:
    QRect buttonCoords() const;
    void moveButton();
    QPoint generateValidPoint() const;

public:
    explicit Widget(QWidget *parent = 0);
    ~Widget();

protected:
    void timerEvent(QTimerEvent *);
    bool eventFilter(QObject *, QEvent *);

private:
    Ui::Widget *ui;

private slots:
   void on_pushButton_clicked();
};

#endif // WIDGET_H

Widget.ui

<?xml version="1.0" encoding="UTF-8"?>
<ui version="4.0">
 <class>Widget</class>
 <widget class="QWidget" name="Widget">
  <property name="geometry">
   <rect>
    <x>0</x>
    <y>0</y>
    <width>400</width>
    <height>300</height>
   </rect>
  </property>
  <property name="windowTitle">
   <string>Push Me!</string>
  </property>
  <widget class="QPushButton" name="pushButton">
   <property name="geometry">
    <rect>
     <x>150</x>
     <y>150</y>
     <width>80</width>
     <height>20</height>
    </rect>
   </property>
   <property name="text">
    <string>Push Me!</string>
   </property>
  </widget>
 </widget>
 <layoutdefault spacing="6" margin="11"/>
 <resources/>
 <connections/>
</ui>