Added new NO_SELECTION constant to ListWindow, and use it to help set and reset default state.

src/core/library/metadata/MetadataValue.cpp

@@ -40,10 +40,9 @@
 using namespace musik::core;
 
 MetadataValue::MetadataValue(const DBID newId, const char *value)
-: id(newId)
-{
-    if(value) {
-        this->value    = value;
+: id(newId) {
+    if (value) {
+        this->value = value;
     }
 }
 

src/musikbox/app/window/CategoryListView.cpp

@@ -35,7 +35,7 @@ void CategoryListView::Requery() {
 
 DBID CategoryListView::GetSelectedId() {
     size_t index = this->GetSelectedIndex();
-    if (this->metadata && index < this->metadata->size()) {
+    if (index != NO_SELECTION && this->metadata && index < this->metadata->size()) {
         return this->metadata->at(index)->id;
     }
     return -1;

src/musikbox/cursespp/ListWindow.cpp

@@ -3,9 +3,11 @@
 
 typedef IScrollAdapter::ScrollPosition ScrollPos;
 
+size_t ListWindow::NO_SELECTION = (size_t) -1;
+
 ListWindow::ListWindow(IWindow *parent) 
 : ScrollableWindow(parent) {
-    this->selectedIndex = 0;
+    this->selectedIndex = (size_t) -1;
 }
 
 ListWindow::~ListWindow() {
@@ -130,6 +132,18 @@ size_t ListWindow::GetSelectedIndex() {
 void ListWindow::OnAdapterChanged() {
     IScrollAdapter *adapter = &GetScrollAdapter();
 
+    size_t count = adapter->GetEntryCount();
+
+    /* update initial state... */
+    if (selectedIndex == NO_SELECTION) {
+        if (adapter->GetEntryCount()) {
+            this->SetSelectedIndex(0);
+        }
+    }
+    else if (count == 0) {
+        this->SetSelectedIndex(NO_SELECTION);
+    }
+
     GetScrollAdapter().DrawPage(
         this->GetContent(),
         this->scrollPosition.firstVisibleEntryIndex,

src/musikbox/cursespp/ListWindow.h

@@ -7,6 +7,8 @@
 
 class ListWindow : public ScrollableWindow {
     public:
+        static size_t NO_SELECTION;
+
         sigslot::signal3<ListWindow*, size_t, size_t> SelectionChanged;
 
         ListWindow(IWindow *parent = NULL);