Enhanced UI for creating and editing foreign keys

CMakeLists.txt

@@ -104,6 +104,7 @@ set(SQLB_MOC_HDR
 	src/ColumnDisplayFormatDialog.h
 	src/FilterLineEdit.h
 	src/RemoteDatabase.h
+	src/ForeignKeyEditorDelegate.h
 )
 
 set(SQLB_SRC
@@ -137,6 +138,7 @@ set(SQLB_SRC
 	src/ColumnDisplayFormatDialog.cpp
 	src/FilterLineEdit.cpp
 	src/RemoteDatabase.cpp
+	src/ForeignKeyEditorDelegate.cpp
 )
 
 set(SQLB_FORMS

src/EditTableDialog.cpp

@@ -1,5 +1,6 @@
 #include "EditTableDialog.h"
 #include "Settings.h"
+#include "ForeignKeyEditorDelegate.h"
 #include "ui_EditTableDialog.h"
 #include "sqlitetablemodel.h"
 #include "sqlitedb.h"
@@ -24,6 +25,8 @@ EditTableDialog::EditTableDialog(DBBrowserDB& db, const QString& tableName, bool
     ui->widgetExtension->setVisible(false);
     connect(ui->treeWidget, SIGNAL(itemChanged(QTreeWidgetItem*,int)),this,SLOT(itemChanged(QTreeWidgetItem*,int)));
 
+    // Set item delegate for foreign key column
+    ui->treeWidget->setItemDelegateForColumn(kForeignKey, new ForeignKeyEditorDelegate(db, m_table, this));
     // Editing an existing table?
     if(m_bNewTable == false)
     {
@@ -80,6 +83,7 @@ void EditTableDialog::updateColumnWidth()
     ui->treeWidget->setColumnWidth(kPrimaryKey, 30);
     ui->treeWidget->setColumnWidth(kAutoIncrement, 30);
     ui->treeWidget->setColumnWidth(kUnique, 30);
+    ui->treeWidget->setColumnWidth(kForeignKey, 500);
 }
 
 void EditTableDialog::populateFields()
@@ -446,16 +450,8 @@ void EditTableDialog::itemChanged(QTreeWidgetItem *item, int column)
                 callRenameColumn = true;
             break;
         case kForeignKey:
-            if(item->text(column).trimmed().isEmpty())
-            {
-                // Remove the foreign key
-                m_table.removeConstraints({field}, sqlb::Constraint::ConstraintTypes::ForeignKeyConstraintType);
-            } else {
-                // Set the foreign key
-                sqlb::ForeignKeyClause* fk = new sqlb::ForeignKeyClause;
-                fk->setFromString(item->text(column));
-                m_table.setConstraint({field}, sqlb::ConstraintPtr(fk));
-            }
+            // handled in delegate
+
             if(!m_bNewTable)
                 callRenameColumn = true;
             break;

src/ForeignKeyEditorDelegate.cpp

@@ -0,0 +1,173 @@
+#include "sqlitedb.h"
+#include "ForeignKeyEditorDelegate.h"
+
+#include <QComboBox>
+#include <QLineEdit>
+#include <QPushButton>
+#include <QHBoxLayout>
+
+class ForeignKeyEditor : public QWidget
+{
+    Q_OBJECT
+
+public:
+    ForeignKeyEditor(QWidget* parent = Q_NULLPTR)
+        : QWidget(parent)
+        , tablesComboBox(new QComboBox(this))
+        , idsComboBox(new QComboBox(this))
+        , clauseEdit(new QLineEdit(this))
+        , m_btnReset(new QPushButton(tr("&Reset"), this))
+    {
+        clauseEdit->setPlaceholderText(tr("(foreign key clauses(ON UPDATE, ON DELETE etc.)"));
+
+        QHBoxLayout* layout = new QHBoxLayout(this);
+        layout->addWidget(tablesComboBox);
+        layout->addWidget(idsComboBox);
+        layout->addWidget(clauseEdit);
+        layout->addWidget(m_btnReset);
+        setLayout(layout);
+
+        connect(m_btnReset, &QPushButton::clicked, [&]
+        {
+            tablesComboBox->setCurrentIndex(-1);
+            idsComboBox->setCurrentIndex(-1);
+            clauseEdit->clear();
+        });
+
+        connect(tablesComboBox, static_cast<void(QComboBox::*)(int)>(&QComboBox::currentIndexChanged),
+                [=](int index)
+        {
+            // reset ids combo box
+            idsComboBox->setCurrentIndex(-1);
+
+            // disable clauses editor if none of tables is selected
+            bool enableClausesEditor = (index!= -1);
+            clauseEdit->setEnabled(enableClausesEditor);
+        });
+    }
+
+    QString getSql() const
+    {
+        if (tablesComboBox->currentText().isEmpty())
+            return QString();
+
+        const QString table     = sqlb::escapeIdentifier(tablesComboBox->currentText());
+        const QString clauses   = clauseEdit->text();
+
+        QString id = idsComboBox->currentText();
+        if (!id.isEmpty())
+            id = QString("(%1)").arg(sqlb::escapeIdentifier(id));
+
+        return QString("%1%2 %3")
+                .arg(table)
+                .arg(id)
+                .arg(clauses)
+                .trimmed();
+    }
+
+    QComboBox* tablesComboBox;
+    QComboBox* idsComboBox;
+    QLineEdit* clauseEdit; // for ON CASCADE and such
+
+private:
+    QPushButton* m_btnReset;
+};
+
+ForeignKeyEditorDelegate::ForeignKeyEditorDelegate(const DBBrowserDB& db, sqlb::Table& table, QObject* parent)
+    : QStyledItemDelegate(parent)
+    , m_db(db)
+    , m_table(table)
+{
+
+}
+
+QWidget* ForeignKeyEditorDelegate::createEditor(QWidget* parent, const QStyleOptionViewItem& option, const QModelIndex& index) const
+{
+    Q_UNUSED(option)
+    Q_UNUSED(index)
+
+    ForeignKeyEditor* editor = new ForeignKeyEditor(parent);
+    editor->setAutoFillBackground(true);
+
+    connect(editor->tablesComboBox, static_cast<void(QComboBox::*)(const QString&)>(&QComboBox::currentIndexChanged),
+            [=](const QString& tableName)
+    {
+        QComboBox* box = editor->idsComboBox;
+        box->clear();
+        box->addItem(QString());                // for those heroes who don't like to specify key explicitly
+        box->addItems(m_tablesIds[tableName]);
+        box->setCurrentIndex(0);
+    });
+
+    return editor;
+}
+
+void ForeignKeyEditorDelegate::setEditorData(QWidget* editor, const QModelIndex& index) const
+{
+    ForeignKeyEditor* fkEditor = static_cast<ForeignKeyEditor*>(editor);
+
+    m_tablesIds.clear();
+    const auto objects = m_db.getBrowsableObjects();
+    for (auto obj : objects) {
+        if ("table" == obj.gettype()) {
+            QString tableName = obj.table.name();
+            m_tablesIds.insert(tableName, obj.table.fieldNames());
+        }
+    }
+
+    fkEditor->tablesComboBox->addItems(m_tablesIds.keys());
+
+    int column = index.row(); // weird? I know right
+    sqlb::FieldPtr field = m_table.fields().at(column);
+    QSharedPointer<sqlb::ForeignKeyClause> fk = m_table.constraint({field}, sqlb::Constraint::ForeignKeyConstraintType).dynamicCast<sqlb::ForeignKeyClause>();
+    if (!fk.isNull()) {
+        fkEditor->tablesComboBox->setCurrentText(fk->table());
+        fkEditor->clauseEdit->setText(fk->constraint());
+        if (!fk->columns().isEmpty())
+            fkEditor->idsComboBox->setCurrentText(fk->columns().first());
+    } else {
+        fkEditor->tablesComboBox->setCurrentIndex(-1);
+    }
+}
+
+void ForeignKeyEditorDelegate::setModelData(QWidget* editor, QAbstractItemModel* model, const QModelIndex& index) const
+{
+    ForeignKeyEditor* fkEditor = static_cast<ForeignKeyEditor*>(editor);
+    QString sql = fkEditor->getSql();
+
+    int column = index.row();
+    sqlb::FieldPtr field = m_table.fields().at(column);
+    if (sql.isEmpty()) {
+        // Remove the foreign key
+        m_table.removeConstraints({field}, sqlb::Constraint::ConstraintTypes::ForeignKeyConstraintType);
+    } else {
+        // Set the foreign key
+        sqlb::ForeignKeyClause* fk = new sqlb::ForeignKeyClause;
+
+        const QString table     = fkEditor->tablesComboBox->currentText();
+        const QString id        = fkEditor->idsComboBox->currentText();
+        const QString clause    = fkEditor->clauseEdit->text();
+
+        fk->setTable(table);
+
+        if (!id.isEmpty())
+            fk->setColumns({id});
+
+        if (!clause.trimmed().isEmpty()) {
+            fk->setConstraint(clause);
+        }
+
+        m_table.setConstraint({field}, sqlb::ConstraintPtr(fk));
+    }
+
+    model->setData(index, sql);
+}
+
+void ForeignKeyEditorDelegate::updateEditorGeometry(QWidget* editor, const QStyleOptionViewItem& option, const QModelIndex& index) const
+{
+    Q_UNUSED(index)
+
+    editor->setGeometry(option.rect);
+}
+
+#include "ForeignKeyEditorDelegate.moc"

src/ForeignKeyEditorDelegate.h

@@ -0,0 +1,34 @@
+#ifndef FOREIGNKEYDELEGATE_H
+#define FOREIGNKEYDELEGATE_H
+
+#include <QStyledItemDelegate>
+
+class DBBrowserDB;
+class QPushButton;
+class QComboBox;
+class QLineEdit;
+
+namespace sqlb
+{
+class Table;
+}
+
+class ForeignKeyEditorDelegate : public QStyledItemDelegate
+{
+    Q_OBJECT
+
+public:
+    explicit ForeignKeyEditorDelegate(const DBBrowserDB& db, sqlb::Table& table, QObject* parent = Q_NULLPTR);
+
+    QWidget* createEditor(QWidget* parent, const QStyleOptionViewItem& option, const QModelIndex& index) const Q_DECL_OVERRIDE;
+    void setEditorData(QWidget* editor, const QModelIndex& index) const Q_DECL_OVERRIDE;
+    void setModelData(QWidget* editor, QAbstractItemModel* model, const QModelIndex& index) const Q_DECL_OVERRIDE;
+    void updateEditorGeometry(QWidget *editor, const QStyleOptionViewItem &option, const QModelIndex &index) const Q_DECL_OVERRIDE;
+
+private:
+    const DBBrowserDB& m_db;
+    sqlb::Table& m_table;
+    mutable QMap<QString, QStringList> m_tablesIds;
+};
+
+#endif // FOREIGNKEYDELEGATE_H

src/src.pro

@@ -52,7 +52,8 @@ HEADERS += \
     FileDialog.h \
     ColumnDisplayFormatDialog.h \
     FilterLineEdit.h \
-    RemoteDatabase.h
+    RemoteDatabase.h \
+    ForeignKeyEditorDelegate.h
 
 SOURCES += \
     sqlitedb.cpp \
@@ -83,7 +84,8 @@ SOURCES += \
     FileDialog.cpp \
     ColumnDisplayFormatDialog.cpp \
     FilterLineEdit.cpp \
-    RemoteDatabase.cpp
+    RemoteDatabase.cpp \
+    ForeignKeyEditorDelegate.cpp
 
 RESOURCES += icons/icons.qrc \
              translations/flags/flags.qrc \