A helper class to access a value from a model in qml

4 files changed, 113 insertions, 0 deletions

diff --git a/framework/mail/CMakeLists.txt b/framework/mail/CMakeLists.txt
index 54a031cc..29fda0e4 100644
--- a/framework/mail/CMakeLists.txt
+++ b/framework/mail/CMakeLists.txt
@@ -13,6 +13,7 @@ set(mailplugin_SRCS
     composer.cpp
     messageparser.cpp
     mailtransport.cpp
+    retriever.cpp
 )
 add_definitions(-DMAIL_DATA_DIR="${CMAKE_CURRENT_SOURCE_DIR}/data")
 
diff --git a/framework/mail/mailplugin.cpp b/framework/mail/mailplugin.cpp
index 750c6f8e..2d19a437 100644
--- a/framework/mail/mailplugin.cpp
+++ b/framework/mail/mailplugin.cpp
@@ -24,6 +24,7 @@
 #include "folderlistmodel.h"
 #include "composer.h"
 #include "messageparser.h"
+#include "retriever.h"
 
 #include <QtQml>
 
@@ -35,4 +36,5 @@ void MailPlugin::registerTypes (const char *uri)
     qmlRegisterType<MailListModel>(uri, 1, 0, "MailListModel");
     qmlRegisterType<Composer>(uri, 1, 0, "Composer");
     qmlRegisterType<MessageParser>(uri, 1, 0, "MessageParser");
+    qmlRegisterType<Retriever>(uri, 1, 0, "Retriever");
 }
diff --git a/framework/mail/retriever.cpp b/framework/mail/retriever.cpp
new file mode 100644
index 00000000..b8e29523
--- /dev/null
+++ b/framework/mail/retriever.cpp
@@ -0,0 +1,55 @@
+/*
+    Copyright (c) 2016 Christian Mollekopf <mollekopf@kolabsystems.com>
+
+    This library is free software; you can redistribute it and/or modify it
+    under the terms of the GNU Library General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or (at your
+    option) any later version.
+
+    This library is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
+    License for more details.
+
+    You should have received a copy of the GNU Library General Public License
+    along with this library; see the file COPYING.LIB.  If not, write to the
+    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+    02110-1301, USA.
+*/
+
+
+#include "retriever.h"
+
+Retriever::Retriever(QObject *parent) : QObject(parent)
+{
+}
+
+QAbstractItemModel* Retriever::model() const
+{
+    return mModel;
+}
+
+void Retriever::setModel(QAbstractItemModel* model)
+{
+    mValue = QVariant();
+    mModel = model;
+    connect(model, &QAbstractItemModel::rowsInserted, this, &Retriever::onRowsInserted);
+    connect(model, &QAbstractItemModel::modelReset, this, &Retriever::onModelReset);
+    if (model->rowCount(QModelIndex())) {
+        mValue = model->index(0, 0, QModelIndex()).data(mModel->roleNames().key(mPropertyName.toLatin1()));
+        emit valueChanged();
+    }
+}
+
+void Retriever::onRowsInserted(const QModelIndex &parent, int first, int last)
+{
+    if (!mValue.isValid()) {
+        mValue = mModel->index(0, 0, QModelIndex()).data(mModel->roleNames().key(mPropertyName.toLatin1()));
+        emit valueChanged();
+    }
+}
+
+void Retriever::onModelReset()
+{
+    mValue = QVariant();
+}
diff --git a/framework/mail/retriever.h b/framework/mail/retriever.h
new file mode 100644
index 00000000..e454532d
--- /dev/null
+++ b/framework/mail/retriever.h
@@ -0,0 +1,55 @@
+/*
+    Copyright (c) 2016 Christian Mollekopf <mollekopf@kolabsystems.com>
+
+    This library is free software; you can redistribute it and/or modify it
+    under the terms of the GNU Library General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or (at your
+    option) any later version.
+
+    This library is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
+    License for more details.
+
+    You should have received a copy of the GNU Library General Public License
+    along with this library; see the file COPYING.LIB.  If not, write to the
+    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+    02110-1301, USA.
+*/
+
+#pragma once
+
+#include <QObject>
+#include <QAbstractItemModel>
+#include <QVariant>
+
+/**
+ * A wrapper for a QAbstractItemModel to retrieve a value from a single index via property binding
+ * 
+ * Assign a model that retrieves the index, set the property your interested in, and propery-bind "value".
+ */
+class Retriever : public QObject
+{
+    Q_OBJECT
+    Q_PROPERTY(QAbstractItemModel* model READ model WRITE setModel)
+    Q_PROPERTY(QString propertyName MEMBER mPropertyName)
+    Q_PROPERTY(QVariant value MEMBER mValue NOTIFY valueChanged)
+
+public:
+    explicit Retriever(QObject *parent = Q_NULLPTR);
+
+    QAbstractItemModel* model() const;
+    void setModel(QAbstractItemModel* model);
+
+signals:
+    void valueChanged();
+
+private slots:
+    void onRowsInserted(const QModelIndex &parent, int first, int last);
+    void onModelReset();
+
+private:
+    QString mPropertyName;
+    QVariant mValue;
+    QAbstractItemModel *mModel;
+};