wrote viewmodel model for project browsing

app/project/projectviewmodel.cpp

@@ -0,0 +1,143 @@
+#include "projectviewmodel.h"
+
+ProjectViewModel::ProjectViewModel(QObject *parent) :
+  QAbstractItemModel(parent),
+  project_(nullptr)
+{
+  // TODO make this configurable
+  columns_.append(kName);
+  columns_.append(kDuration);
+  columns_.append(kRate);
+}
+
+Project *ProjectViewModel::project()
+{
+  return project_;
+}
+
+void ProjectViewModel::set_project(Project *p)
+{
+  beginResetModel();
+
+  project_ = p;
+
+  endResetModel();
+}
+
+QModelIndex ProjectViewModel::index(int row, int column, const QModelIndex &parent) const
+{
+  // I'm actually not 100% sure what this does, but it seems logical and was in the earlier code
+  if (!hasIndex(row, column, parent)) {
+    return QModelIndex();
+  }
+
+  // Get the parent object (project root if the index is invalid)
+  Item* item_parent = (parent.isValid()) ? static_cast<Item*>(parent.internalPointer()) : project_->root();
+
+  // Return an index to this object
+  return createIndex(row, column, item_parent->child(row));
+}
+
+QModelIndex ProjectViewModel::parent(const QModelIndex &child) const
+{
+  // Get the Item object from the index
+  Item* item = static_cast<Item*>(child.internalPointer());
+
+  // Get Item's parent object
+  Item* parent = item->parent();
+
+  // If the parent is the root, return an empty index
+  if (parent == project_->root()) {
+    return QModelIndex();
+  }
+
+  // Otherwise return a true index to its parent
+
+  // Find parent's index within its own parent
+  // (TODO: this model should handle sorting, which means it'll have to "know" the indices)
+  int child_index = -1;
+
+  Item* double_parent = parent->parent();
+  for (int i=0;i<double_parent->child_count();i++) {
+    if (double_parent->child(i) == parent) {
+      child_index = i;
+      break;
+    }
+  }
+
+  // Make sure the index is valid (there's no reason it shouldn't be)
+  Q_ASSERT(child_index > -1);
+
+  // Return an index to the parent
+  return createIndex(child_index, 0, parent);
+}
+
+int ProjectViewModel::rowCount(const QModelIndex &parent) const
+{
+  // If there's no project, there are obviously no items to show
+  if (project_ == nullptr) {
+    return 0;
+  }
+
+  // If the index is the root, return the root child count
+  if (parent == QModelIndex()) {
+    return project_->root()->child_count();
+  }
+
+  // Otherwise, the index must contain a valid pointer, so we just return its child count
+  return static_cast<Item*>(parent.internalPointer())->child_count();
+}
+
+int ProjectViewModel::columnCount(const QModelIndex &parent) const
+{
+  Q_UNUSED(parent)
+
+  // Not strictly necessary, but a decent visual cue that there's no project currently active
+  if (project_ == nullptr) {
+    return 0;
+  }
+
+  return columns_.size();
+}
+
+QVariant ProjectViewModel::data(const QModelIndex &index, int role) const
+{
+  if (role == Qt::DisplayRole) {
+
+    ColumnType column_type = columns_.at(index.column());
+
+    switch (column_type) {
+    case kName:
+      return static_cast<Item*>(index.internalPointer())->name();
+    case kDuration:
+      return "00:00:00;00";
+    case kRate:
+      return "29.97 FPS";
+    }
+  }
+
+  // TODO Add DecorationRole to column 1 for icons
+
+  return QVariant();
+}
+
+QVariant ProjectViewModel::headerData(int section, Qt::Orientation orientation, int role) const
+{
+  // Check if we need text data (DisplayRole) and orientation is horizontal
+  // FIXME I'm not 100% sure what happens if the orientation is vertical/if that check is necessary
+  if (orientation == Qt::Horizontal && role == Qt::DisplayRole) {
+    ColumnType column_type = columns_.at(section);
+
+    // Return the name based on the column's current type
+    switch (column_type) {
+    case kName:
+      return tr("Name");
+    case kDuration:
+      return tr("Duration");
+    case kRate:
+      return tr("Rate");
+    }
+  }
+
+  return QAbstractItemModel::headerData(section, orientation, role);
+}