#include "errorexample.h"

#include <QFile>
#include <QLabel>
#include <QPushButton>
errorexample::errorexample() {
  // 1.δ°üº¬±ØÒªµÄÍ·Îļþ
  // ´íÎó£ºÈ±ÉÙ #include <QLabel>
  QLabel label("Hello");  // ±àÒë´íÎó£º'QLabel' was not declared in this scope
  label.show();

  //-----------Ö¸Õë³£¼ûÎÊÌâ---------------

  //¢Ù¿ÕÖ¸Õë½âÒýÓÃ
  QWidget *widget = nullptr;
  widget->show();  //¶ÔֵΪnullptrµÄÖ¸Õë½øÐзÃÎʲÙ×÷,»áÒý·¢±ÀÀ£

  //½â¾ö°ì·¨£º
  QWidget *widget1 = nullptr;
  if (widget1) {  //ʹÓÃÖ¸ÕëÇ°£¬ÏÈÈ·ÈÏÆäÊÇ·ñΪnullptr
    widget1->show();
  }

  //¢ÚÒ°Ö¸Õë
  //Ö¸ÕëËùÖ¸ÏòµÄÄÚ´æÒѾ­±»ÊÍ·Å£¬µ«ºóÐøÈÔÔÚʹÓøÃÖ¸Õë
  QWidget *widget2 = new QWidget;
  delete widget2;
  widget2->show();  //´Ëʱwidget2ÒѾ­±ä³ÉÒ°Ö¸Õë

  //½â¾ö°ì·¨:
  //¶ÔÏóÊÍ·ÅÖ®ºó£¬¼°Ê±½«Ö¸ÕëÖÃΪnullptr(ÀûÓà Qt
  //¶ÔÏóµÄ¸¸×Ó¹Øϵ»úÖÆÀ´×Ô¶¯¹ÜÀíÄÚ´æ)
  QWidget *widget3 = new QWidget;
  delete widget3;
  widget3 = nullptr;  //±ÜÃâÒ°Ö¸Õë

  //¢ÛÄÚ´æй¶£ºÎ´ÊͷŶ¯Ì¬·ÖÅäµÄÄÚ´æ
  void createLeak() {
    int *ptr = new int(10);  //·ÖÅäºóδÊÍ·Å
  }
  //½â¾ö°ì·¨£º
  void createLeak() {
    int *ptr = new int(10);  //·ÖÅäºóδÊÍ·Å
    delete ptr;
    ptr = nullptr;
  }

  //¢Ü¸¸×Ó¹ØϵÎóÓÃ
  QWidget *parent = new QWidget;
  QPushButton *button = new QPushButton(parent);
  delete button;  // ÊÖ¶¯É¾³ý×Ó¶ÔÏó
  delete parent;  // ±ÀÀ££¡¸¸¶ÔÏóÊÔͼÔÙ´Îɾ³ýÒÑÊÍ·ÅµÄ button

  //½â¾ö°ì·¨£ºÒÀÀµ¶ÔÏóÊ÷×Ô¶¯¹ÜÀí
  QWidget *parent2 = new QWidget;
  QPushButton *button2 = new QPushButton(parent);
  delete parent2;  // ×Ô¶¯É¾³ýËùÓÐ×Ó¶ÔÏ󣨰üÀ¨ button£©

  //¢ÝÖÇÄÜÖ¸ÕëÓë¶ÔÏóÊ÷³åÍ»
  //»ìºÏʹÓø¸¶ÔÏóºÍÖÇÄÜÖ¸Õë
  QWidget *parent3 = new QWidget;
  // ´íÎ󣺸¸¶ÔÏóÒѹÜÀí button£¬ÖÇÄÜÖ¸Õë»áµ¼ÖÂË«ÖØÊÍ·Å
  std::unique_ptr<QPushButton> button3(new QPushButton(parent));

  //½â¾ö°ì·¨1£º½öÓø¸¶ÔÏó¹ÜÀí
  QWidget *parent4 = new QWidget;
  QPushButton *button4 = new QPushButton(parent4);  // ¸¸¶ÔÏó¸ºÔðÊÍ·Å

  //½â¾ö°ì·¨2£ºÎÞ¸¸¶ÔÏóʱʹÓÃÖÇÄÜÖ¸Õë
  std::unique_ptr<QPushButton> button5 = std::make_unique<QPushButton>();

  //¢ÞÈÝÆ÷ÖеÄÖ¸Õë¹ÜÀí
  // Íü¼ÇÊÍ·ÅfilesÊý×é¼°ÆäÖеÄÖ¸ÕëËùÖ¸ÏòµÄÄÚ´æ
  QFile *files = new QFile[10];
  for (int i = 0; i < 10; ++i) {
    files[i].setFileName("file" + QString::number(i));
  }

  //½â¾ö°ì·¨£º
  QFile **files1 = new QFile *[10];
  for (int i = 0; i < 10; ++i) {
    files[i].setFileName("file" + QString::number(i));
  }
  for (int i = 0; i < 10; ++i) {
    delete files1[i];
  }
  delete[] files;

  //-----------³£¼ûÂß¼­´íÎó---------------

  //¢ÙÎÞÏÞÑ­»·
  //´íÎ󣺣¨ÎÞÖÕÖ¹Ìõ¼þ£©
  for (int i = 0; i < 10;) {
    qDebug() << "Looping...";
    // Íü¼Çдi++
  }

  //´íÎó£ºËÀÑ­»·£¨Ìõ¼þºãΪÕ棩
  while (true) {
    //´úÂë¿é          δÌṩÍ˳ö»úÖÆ
  }

  //½â¾ö°ì·¨
  // Ôö¼Ói++
  for (int i = 0; i < 10; i++) {
    qDebug() << "Looping..." << i;
  }

  //ʹÓÃbreak»òreturnÍ˳öÑ­»·
  while (true) {
    if (data.isEmpty()) break;  // Ìõ¼þÂú×ãʱÍ˳ö
  }

  //¢ÚÊý¾Ý/ÈÝÆ÷Ô½½ç·ÃÎÊ
  // ´íÎ󣺷ÃÎÊÔ½½ç£¨Ë÷Òý0~9£¬µ«Ñ­»·µ½i=10£©
  QVector<int> numbers(10);
  for (int i = 0; i <= 10; ++i) {  // ӦΪi < 10
    numbers[i] = i;                // i=10ʱԽ½ç
    // ´íÎó£ºÊ¹ÓÿÕÈÝÆ÷
    QStringList names;
    qDebug() << names[0];  // ·ÃÎÊ¿ÕÈÝÆ÷µÄµÚÒ»¸öÔªËØ

    //½â¾ö°ì·¨
    //ʹÓð²È«µÄ·ÃÎÊ·½·¨£¨Èçat()´úÌæ[]£©
    qDebug() << numbers.at(10);
    //¼ì²éÈÝÆ÷ÊÇ·ñΪ¿Õ
    if (!names.isEmpty()) {
      qDebug() << names[0];
    }

    // 2.δ³õʼ»¯Ö¸Õë
    QLabel *label4;
    label4->setText("Hello");  // ´íÎó£ºÊ¹ÓÃδ³õʼ»¯µÄÖ¸Õë

    // ÐÞ¸´£º³õʼ»¯Ö¸Õë
    QLabel *label5 = new QLabel;

    // 3.¸¸¶ÔÏó¹ÜÀí²»µ±µ¼ÖÂÄÚ´æй¶
    QLabel *label1 = new QLabel("Memory Leak");
    label1->show();

    // ÕýÈ·×ö·¨£ºÉèÖø¸¶ÔÏó£¬Qt»á×Ô¶¯¹ÜÀíÄÚ´æ
    QWidget *parent = new QWidget;
    QLabel *managedLabel = new QLabel("Managed", parent);

    // 4.ʹÓÃÒÑɾ³ýµÄ¶ÔÏó
    QLabel *label2 = new QLabel("Delete Me");
    delete label2;

    // ´íÎ󣺷ÃÎÊÒÑɾ³ýµÄ¶ÔÏó
    label2->setText("Oops");  // 䶨ÒåÐÐΪ

    // 5.×Ö·û´®±àÂëÎÊÌâ
    QLabel *label3 = new QLabel;
    // ´íÎó£ºÓ²±àÂë·ÇASCII×Ö·û´®
    label3->setText("ÖÐÎÄÎı¾");  // ¿ÉÄÜÏÔʾÂÒÂ룬ȡ¾öÓÚÔ´Îļþ±àÂë

    // ÕýÈ·×ö·¨£ºÊ¹ÓÃtr()½øÐз­Òë
    label3->setText(tr("ÖÐÎÄÎı¾"));

    // 6.ÈÝÆ÷Ô½½ç·ÃÎÊ
    QList<int> list = {1, 2, 3};

    // ´íÎó£ºÔ½½ç·ÃÎÊ
    int value = list[3];  // Ë÷Òý×î´óΪ2

    // ÕýÈ·×ö·¨£ºÊ¹ÓÃat()²¢¼ì²é±ß½ç
    if (list.size() > 3) {
      int safeValue = list.at(3);  // at()»áÔÚÔ½½çʱÅ׳öÒì³£
    }

    // 7.ȱʧÖÕÖ¹Ìõ¼þµÄForÑ­»·
    for (int i = 0;; i++) {  // ´íÎó£ºÎÞÖÕÖ¹Ìõ¼þ
                             //Ñ­»·Ìå
    }

    // Õýȷд·¨£º
    for (int i = 0; i < 10; i++) {  // Ìí¼ÓÖÕÖ¹Ìõ¼þ
                                    //Ñ­»·Ìå
    }

    // 8.ÎóÓÃ = ´úÌæ ==
    if (x = 5) {  // Î󽫸³Öµ²Ù×÷µ±×÷±È½Ï£¬Ìõ¼þʼÖÕΪ true£¨³ý·Ç x ÊDz¼¶ûÀàÐÍ£©
                  // ...
    }

    // 9.ʼþ´¦Àíδµ÷ÓûùÀàʵÏÖ
    void CustomWidget::paintEvent(QPaintEvent * event) {
      // ´íÎó£ºÎ´µ÷ÓûùÀàʵÏÖ
      QPainter painter(this);
      // ȱÉÙ£ºQWidget::paintEvent(event);
    }

    // 10.ÐźŲ۲ÎÊý²»Æ¥Åä
    // ´íÎó£ºÐźŲÎÊýÓë²Û²ÎÊýÀàÐͲ»Æ¥Åä
    connect(sender, &Sender::valueChanged(int), receiver,
            &Receiver::updateValue(QString));

    // ÐÞ¸´£ºÈ·±£²ÎÊýÀàÐÍÒ»ÖÂ
    connect(sender, &Sender::valueChanged(int), receiver,
            &Receiver::updateValue(int));

    // 11.δʵÏÖ´¿Ð麯Êý
    class MyInterface {
     public:
      virtual void pureVirtual() = 0;
    };

    class MyClass : public MyInterface {
      // ´íÎó£ºÎ´ÊµÏÖ´¿Ð麯Êý
    };

    // ÐÞ¸´£ºÊµÏÖ´¿Ð麯Êý
    void MyClass::pureVirtual() { /* ʵÏÖ */
    }

    // 12.δÕýȷʵÏÖ¿½±´¹¹Ô캯Êý
    class MyClass1 {
     public:
      QWidget *widget;
      MyClass1(const MyClass1 &other) {
        widget = other.widget;
      }  // ´íÎó£ºÇ³¿½±´
    };

    // ÐÞ¸´£ºÉ±´»ò½ûÓÿ½±´¹¹Ô캯Êý
    MyClass1(const MyClass1 &other) = delete;
  }