Qt : Crash - was it the code or do I need to insert some other command? - xdebug

Question

When I run the following code, it throws an error
The inferior stopped because it received a signal from the operating system.
Signal name: SIGSEGV
Signal meaning: Segmentation fault
This is my code, I'm wondering where I went wrong?
I wanted to shown some random blocks on the window, but it got failed
mainwindow.cpp
#include "mainwindow.h"
#include <ctime>
#include <QPixmap>
#include <QPainter>
MainWindow::MainWindow(QWidget *parent)
: QMainWindow(parent)
{
this->setFixedSize(win_width,win_height);
this->setWindowIcon(QIcon(":/Image/icon.png"));
this->setWindowTitle("Qt POPONG");
startpage = new StartPage(this);
for (int i=0; i<80; i++){
block_[i] = new block(this);
}
gameRedy();
startpage->show();
}
void MainWindow::paintEvent(QPaintEvent *)
{
QPainter painter(this);
QPixmap bgImg;
bgImg.load(":/Image/bg.png");
painter.drawPixmap(0,0,win_width,win_height,bgImg);
}
void MainWindow::mousePressEvent(QMouseEvent *event)
{
}
void MainWindow::keyPressEvent(QKeyEvent *event)
{
if (event->key()==Qt::Key_S) {
gameStart();
startpage->close();
}
}
void MainWindow::createBlocks()
{
int startx = 0, starty = 0;
int WW;
int HH;
qsrand(time(NULL));
for (int i=0; i<blockcount; i++){
while(1){
WW = qrand()%10;
HH = qrand()%12;
if (blockShowW[WW]==0 && blockShowH[HH]==0){
block_[i]->move(startx+WW*50, starty+HH*50);
blockShowW[WW]=1;
blockShowH[HH]=1;
break;
}
}
}
blockTimer = new QTimer(this);
//connect(blockTimer,SIGNAL(timeout()),this,SLOT(blockAction()));
blockTValue = 8;
}
/*void MainWindow::blockAction()
{
int startx = 0, starty = 0;
int WW;
int HH;
for (int i=0; i<blockcount; i++){
while(1){
WW = qrand()%10;
HH = qrand()%12;
if (blockShowW[WW]!=0 && blockShowH[HH]!=0){
block_[i]->move(startx+WW*50, starty+HH*50);
blockShowW[WW]=1;
blockShowH[HH]=1;
break;
}
}
}
}*/
void MainWindow::gameRedy()
{
gamemod=redy;
createBlocks();
}
void MainWindow::gameLose()
{
gamemod=lose;
}
void MainWindow::gameStart()
{
gamemod=start;
//blockTimer->start(blockTValue);
}
Mainwindow.h
#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <QMainWindow>
#include <QApplication>
#include <QMouseEvent>
#include <QTimer>
#include "startpage.h"
#include "plate.h";
#include "block.h";
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
MainWindow(QWidget *parent = 0);
int win_width=500;
int win_height=700;
protected:
void paintEvent(QPaintEvent *);
void mousePressEvent(QMouseEvent *event);
void keyPressEvent(QKeyEvent *event);
private slots:
//void blockAction();
private:
void gameLose();
void gameStart();
void gameRedy();
void createBlocks();
enum{lose=0,start=1,redy=2};
int gamemod;
StartPage *startpage;
enum{blockcount=10};
block *block_[blockcount];
QTimer *blockTimer;
int blockTValue;
int blockShowW[11]={0};
int blockShowH[13]={0};
};
#endif // MAINWINDOW_H
block.cpp
#include "block.h"
block::block(QWidget *parent) : QWidget(parent)
{
this->setFixedSize(W,H);
this->color = (qrand()%7)+1;
}
void block::paintEvent(QPaintEvent *)
{
QPainter painter(this);
QPixmap object;
switch(this->color){
case 1:
object.load(":/Image/blocks/1.png");
break;
case 2:
object.load(":/Image/blocks/2.png");
break;
case 3:
object.load(":/Image/blocks/3.png");
break;
case 4:
object.load(":/Image/blocks/4.png");
break;
case 5:
object.load(":/Image/blocks/5.png");
break;
case 6:
object.load(":/Image/blocks/6.png");
break;
default:
object.load(":/Image/blocks/7.png");
break;
}
painter.drawPixmap(0,0,W,H,object);
}
block.h
#ifndef BLOCK_H
#define BLOCK_H
#include <QWidget>
#include <QPainter>
#include <QPixmap>
class block : public QWidget
{
Q_OBJECT
public:
explicit block(QWidget *parent = 0);
int W = 50;
int H = 50;
private:
int color;
protected:
void paintEvent(QPaintEvent *);
};
#endif // BLOCK_H