Fix SmTreeModel for good

Back to the basics! Should have read the reference implementation of
QAbstractItemModel::index() earlier, much earlier. Now it just works
(tm)!

1 files changed, 15 insertions, 17 deletions

diff --git a/smtreemodel.cpp b/smtreemodel.cpp
index 98fa4c8..088d393 100644
--- a/smtreemodel.cpp
+++ b/smtreemodel.cpp
@@ -9,8 +9,6 @@
 #include <QSettings>
 #include <QBrush>
 
-#include <QDebug>
-
 #include "smtreemodel.h"
 #include "smtreeitem.h"
 #include "smglobals.h"
@@ -42,20 +40,20 @@ int SmTreeModel::columnCount(const QModelIndex &parent) const{
 }
 
 QModelIndex SmTreeModel::index(int row, int column, const QModelIndex &parent) const{
-    // return child from root if parent is invalid
-    // this was difficult to figure this out!
+    if(!hasIndex(row, column, parent)){
+        return QModelIndex();
+    }
+    SmTreeItem *parentItem;
     if(!parent.isValid()){
-        return createIndex(row, column, mRootItem->child(row));
+        parentItem = mRootItem;
+    }else{
+        parentItem = static_cast<SmTreeItem*>(parent.internalPointer());
     }
-    SmTreeItem *parentItem = static_cast<SmTreeItem*>(parent.internalPointer());
-    if( (parentItem == 0) ||
-        (row < 0) ||
-        (column < 0) ||
-        (row >= parentItem->childCount()) ||
-        (column > parentItem->columnCount())){
-            return QModelIndex();
+    SmTreeItem *childItem = parentItem->child(row);
+    if(childItem){
+        return createIndex(row, column, childItem);
     }
-    return createIndex(row, column, parentItem->child(row));
+    return QModelIndex();
 }
 
 QModelIndex SmTreeModel::parent(const QModelIndex &child) const{
@@ -66,10 +64,10 @@ QModelIndex SmTreeModel::parent(const QModelIndex &child) const{
     SmTreeItem *childItem = static_cast<SmTreeItem*>(child.internalPointer());
 	SmTreeItem *parentItem = childItem->parent();
 
-    if(parentItem == 0){
-		return QModelIndex();
-	}
-    return createIndex(parentItem->row(), child.column(), parentItem);
+    if(parentItem == mRootItem){
+        return QModelIndex();
+    }
+    return createIndex(parentItem->row(), 0, parentItem);
 }
 
 Qt::ItemFlags SmTreeModel::flags(const QModelIndex &index) const{