SM-26 synthesizer: initial implementation

Source/MenuSystem.cpp

@@ -0,0 +1,124 @@
+#include "MenuSystem.h"
+
+MenuSystem::MenuSystem() {}
+
+void MenuSystem::setRootScreenBuilder (ScreenBuilder fn) { rootBuilder = fn; }
+
+void MenuSystem::rebuildRoot()
+{
+    if (rootBuilder)
+    {
+        MenuScreen root = rootBuilder();
+        stack.clear();
+        stack.push_back (root);
+    }
+}
+
+void MenuSystem::open()
+{
+    wasOpen = true;
+    rebuildRoot();
+}
+
+void MenuSystem::close()
+{
+    stack.clear();
+    wasOpen = false;
+}
+
+void MenuSystem::pushScreen (const MenuScreen& screen) { stack.push_back (screen); }
+
+const MenuScreen& MenuSystem::current() const
+{
+    if (stack.empty())
+    {
+        static MenuScreen empty;
+        empty.title = "";
+        empty.selected = 0;
+        return empty;
+    }
+    return stack.back();
+}
+
+void MenuSystem::refreshCurrent()
+{
+    if (! stack.empty())
+    {
+        int sel = stack.back().selected;
+        stack.pop_back();
+        if (stack.empty() && rootBuilder)
+        {
+            MenuScreen root = rootBuilder();
+            root.selected = sel;
+            stack.push_back (root);
+        }
+        else if (! stack.empty())
+        {
+            stack.back().selected = sel;
+        }
+    }
+}
+
+void MenuSystem::up()
+{
+    if (stack.empty()) return;
+    auto& s = stack.back();
+    if (s.items.empty()) return;
+
+    int newSel = s.selected - 1;
+    while (newSel >= 0 && s.items[(size_t) newSel].kind == MenuItem::Separator)
+        --newSel;
+    if (newSel >= 0)
+        s.selected = newSel;
+}
+
+void MenuSystem::down()
+{
+    if (stack.empty()) return;
+    auto& s = stack.back();
+    if (s.items.empty()) return;
+
+    int newSel = s.selected + 1;
+    while (newSel < (int) s.items.size() && s.items[(size_t) newSel].kind == MenuItem::Separator)
+        ++newSel;
+    if (newSel < (int) s.items.size())
+        s.selected = newSel;
+}
+
+void MenuSystem::left()
+{
+    if (stack.empty()) return;
+    auto& s = stack.back();
+    if (s.items.empty()) return;
+    auto& item = s.items[(size_t) s.selected];
+    if (item.kind == MenuItem::Value && item.onAdjust)
+        item.onAdjust (-0.02f);
+}
+
+void MenuSystem::right()
+{
+    if (stack.empty()) return;
+    auto& s = stack.back();
+    if (s.items.empty()) return;
+    auto& item = s.items[(size_t) s.selected];
+    if (item.kind == MenuItem::Value && item.onAdjust)
+        item.onAdjust (0.02f);
+}
+
+void MenuSystem::enter()
+{
+    if (stack.empty()) return;
+    auto& s = stack.back();
+    if (s.items.empty()) return;
+    auto& item = s.items[(size_t) s.selected];
+    if (item.onEnter)
+        item.onEnter();
+}
+
+void MenuSystem::escape()
+{
+    if (stack.size() > 1)
+        stack.pop_back();
+    else if (stack.size() == 1)
+        close();
+}