add: widget form to insert records into random_data

widget.cpp

@@ -1,5 +1,65 @@
 #include "widget.h"
+#include <QSqlQuery>
 
-Widget::Widget (QWidget *parent) : QWidget (parent) {}
+Widget::Widget(QWidget *parent)
+    : QWidget(parent)
+    , _grid(new QGridLayout(this))
+    , _countId(new QLabel("NULL"))
+    , _nameLabel(new QLabel("name: "))
+    , _nameEdit(new QLineEdit())
+    , _textLabel(new QLabel("text:"))
+    , _textEdit(new QTextEdit())
+    , _addBtn(new QPushButton("&ADD"))
+{
+    _grid->addWidget(_countId, 0, 0, Qt::AlignHCenter);
+    _grid->addWidget(_nameLabel, 1, 0, Qt::AlignRight);
+    _grid->addWidget(_nameEdit, 1, 1, Qt::AlignVCenter);
+    _grid->addWidget(_textLabel, 2, 0, Qt::AlignRight);
+    _grid->addWidget(_textEdit, 2, 1, Qt::AlignHCenter);
+    _grid->addWidget(_addBtn, 3, 0, Qt::AlignHCenter);
+    setLayout(_grid);
+
+    connect(_addBtn, &QPushButton::clicked, this, &Widget::addRecord);
+}
 
 Widget::~Widget () {}
+
+void Widget::init(const QSqlDatabase &db)
+{
+    _db = db;
+    if (!_db.isOpen()) {
+        close();
+        return;
+    }
+    QSqlQuery query(_db);
+    if (query.exec("SELECT COUNT(*) FROM random_data")) {
+        auto countRecord = query.value(0).toString();
+        count = query.value(0).toInt();
+        if (!countRecord.isEmpty()) {
+            _countId->setText(countRecord);
+        }
+    }
+    show();
+}
+
+void Widget::addRecord()
+{
+    if (_nameEdit->displayText().isEmpty() || _textEdit->toPlainText().isEmpty()) {
+        return;
+    }
+    if (!_db.isOpen()) {
+        return;
+    }
+    QSqlQuery query(_db);
+    query.prepare("INSERT INTO public.random_data (name, text) "
+                  "VALUES (?, ?)");
+    query.addBindValue(_nameEdit->displayText());
+    query.addBindValue(_textEdit->toHtml());
+    if (!query.exec()) {
+        return;
+    }
+    _nameEdit->clear();
+    _textEdit->clear();
+    ++count;
+    _countId->setText(QString::number(count, 10));
+}

widget.h

@@ -1,6 +1,12 @@
 #ifndef WIDGET_H
 #define WIDGET_H
 
+#include <QGridLayout>
+#include <QLabel>
+#include <QLineEdit>
+#include <QPushButton>
+#include <QSqlDatabase>
+#include <QTextEdit>
 #include <QWidget>
 
 class Widget : public QWidget
@@ -8,7 +14,21 @@ class Widget : public QWidget
   Q_OBJECT
 
 public:
-  Widget (QWidget *parent = nullptr);
-  ~Widget ();
+    Widget(QWidget *parent = nullptr);
+    ~Widget();
+
+private:
+    QSqlDatabase _db;
+    QGridLayout *_grid = nullptr;
+    QLabel *_countId = nullptr;
+    QLabel *_nameLabel = nullptr;
+    QLineEdit *_nameEdit = nullptr;
+    QLabel *_textLabel = nullptr;
+    QTextEdit *_textEdit = nullptr;
+    QPushButton *_addBtn = nullptr;
+    quint64 count = 0;
+public slots:
+    void init(const QSqlDatabase &);
+    void addRecord();
 };
 #endif // WIDGET_H