Add a new model: SsrfFilterProxyModel

Add a new Model, it's the QSortFilterProxyModel that accepts
functions to filter / sort. so instead of creating a new class
for each different sorting (overkill), now we can just create
a function and pass to this class.  I'll rework the filtering
system of subsurface to use this - in the meantime I've created
this to ease the creation of another filter: the dive sites
by gps coordinates.

Signed-off-by: Tomaz Canabrava <tomaz.canabrava@intel.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

CMakeLists.txt

@@ -390,6 +390,7 @@ set(SUBSURFACE_MODELS_LIB_SRCS
 	qt-models/diveplotdatamodel.cpp
 	qt-models/divelocationmodel.cpp
 	qt-models/divesitepicturesmodel.cpp
+	qt-models/ssrfsortfilterproxymodel.cpp
 )
 source_group("Subsurface Models" FILES ${SUBSURFACE_MODELS})
 

qt-models/ssrfsortfilterproxymodel.cpp

@@ -0,0 +1,42 @@
+#include "ssrfsortfilterproxymodel.h"
+
+SsrfSortFilterProxyModel::SsrfSortFilterProxyModel(QObject *parent)
+: QSortFilterProxyModel(parent), less_than(0), accepts_col(0), accepts_row(0)
+{
+}
+
+bool SsrfSortFilterProxyModel::lessThan(const QModelIndex& source_left, const QModelIndex& source_right) const
+{
+	Q_ASSERT(less_than);
+	const QAbstractItemModel *self = this;
+	return less_than(const_cast<QAbstractItemModel*>(self), source_left, source_right);
+}
+
+bool SsrfSortFilterProxyModel::filterAcceptsRow(int source_row, const QModelIndex& source_parent) const
+{
+	Q_ASSERT(accepts_row);
+	const QAbstractItemModel *self = this;
+	return accepts_row(const_cast<QAbstractItemModel*>(self), source_row, source_parent);
+}
+
+bool SsrfSortFilterProxyModel::filterAcceptsColumn(int source_column, const QModelIndex& source_parent) const
+{
+	Q_ASSERT(accepts_col);
+	const QAbstractItemModel *self = this;
+	return accepts_col(const_cast<QAbstractItemModel*>(self), source_column, source_parent);
+}
+
+void SsrfSortFilterProxyModel::setLessThan(less_than_cb func)
+{
+	less_than = func;
+}
+
+void SsrfSortFilterProxyModel::setFilterRow(filter_accepts_row_cb func)
+{
+	accepts_row = func;
+}
+
+void SsrfSortFilterProxyModel::setFilterCol(filter_accepts_col_cb func)
+{
+	accepts_col = func;
+}

qt-models/ssrfsortfilterproxymodel.h

@@ -0,0 +1,33 @@
+#ifndef SSRFSORTFILTERPROXYMODEL_H
+#define SSRFSORTFILTERPROXYMODEL_H
+
+#include <QSortFilterProxyModel>
+
+typedef bool (*filter_accepts_col_cb) (QAbstractItemModel *model,int sourceRow, const QModelIndex& parent);
+typedef bool (*filter_accepts_row_cb) (QAbstractItemModel *model,int sourceRow, const QModelIndex& parent);
+typedef bool (*less_than_cb) (QAbstractItemModel *model, const QModelIndex& left, const QModelIndex& right);
+
+/* Use this class when you wanna a quick filter.
+ * instead of creating a new class, just create a new instance of this class
+ * and plug your callback.
+ */
+class SsrfSortFilterProxyModel : public QSortFilterProxyModel {
+	Q_OBJECT
+
+public:
+	SsrfSortFilterProxyModel(QObject *parent = 0);
+	virtual bool lessThan(const QModelIndex& source_left, const QModelIndex& source_right) const;
+	virtual bool filterAcceptsRow(int source_row, const QModelIndex& source_parent) const;
+	virtual bool filterAcceptsColumn(int source_column, const QModelIndex& source_parent) const;
+
+	void setLessThan(less_than_cb func);
+	void setFilterRow(filter_accepts_row_cb func);
+	void setFilterCol(filter_accepts_col_cb func);
+
+private:
+	less_than_cb less_than;
+	filter_accepts_col_cb accepts_col;
+	filter_accepts_row_cb accepts_row;
+};
+
+#endif