Make the selection loop with arrow keys in the autocomplete popup

third_party/WebKit/WebCore/platform/chromium/PopupMenuChromium.cpp

Index: third_party/WebKit/WebCore/platform/chromium/PopupMenuChromium.cpp
===================================================================
--- third_party/WebKit/WebCore/platform/chromium/PopupMenuChromium.cpp	(revision 8275)
+++ third_party/WebKit/WebCore/platform/chromium/PopupMenuChromium.cpp	(working copy)
@@ -89,27 +89,27 @@
 
     // PopupListBox methods
 
-    // Show the popup
+    // Shows the popup
     void showPopup();
 
-    // Hide the popup.  Do not call this directly: use client->hidePopup().
+    // Hides the popup.  Do not call this directly: use client->hidePopup().
     void hidePopup();
 
-    // Update our internal list to match the client.
+    // Updates our internal list to match the client.
     void updateFromElement();
 
-    // Free any allocated resources used in a particular popup session. 
+    // Frees any allocated resources used in a particular popup session. 
     void clear();
 
-    // Set the index of the option that is displayed in the <select> widget in the page
+    // Sets the index of the option that is displayed in the <select> widget in the page
     void setOriginalIndex(int index);
 
-    // Get the index of the item that the user is currently moused over or has selected with
+    // Gets the index of the item that the user is currently moused over or has selected with
     // the keyboard. This is not the same as the original index, since the user has not yet
     // accepted this input.
     int selectedIndex() const { return m_selectedIndex; }
 
-    // Move selection down/up the given number of items, scrolling if necessary.
+    // Moves selection down/up the given number of items, scrolling if necessary.
     // Positive is down.  The resulting index will be clamped to the range
     // [0, numItems), and non-option items will be skipped.
     void adjustSelectedIndex(int delta);
@@ -119,7 +119,7 @@
 
     void setBaseWidth(int width) { m_baseWidth = width; }
 
-    // Compute size of widget and children.
+    // Computes the size of widget and children.
     void layout();
 
     // Returns whether the popup wants to process events for the passed key.
@@ -133,6 +133,12 @@
     // abandonned.
     void setAcceptOnAbandon(bool value) { m_shouldAcceptOnAbandon = value; }
 
+    // Sets whether pressing the down/up arrow when the last/first row is
+    // selected clears the selection on the first key press and then selects the
+    // first/last row on the next key press.  If false, the selected row stays
+    // the last/first row.
+    void setLoopSelectionNavigation(bool value) { m_loopSelectionNavigation = value; }
+
 private:
     friend class PopupContainer;
     friend class RefCounted<PopupListBox>;
@@ -163,6 +169,7 @@
         , m_repeatingChar(0)
         , m_lastCharTime(0)
         , m_setTextOnIndexChange(true)
+        , m_loopSelectionNavigation(false)
     {
         setScrollbarModes(ScrollbarAlwaysOff, ScrollbarAlwaysOff);
     }
@@ -186,6 +193,9 @@
     // Disabled items, or labels cannot be selected.
     bool isSelectableItem(int index);
 
+    // Clears the selection (so no row appears selected).
+    void clearSelection();
+
     // Scrolls to reveal the given index.
     void scrollToRevealRow(int index);
     void scrollToRevealSelection() { scrollToRevealRow(m_selectedIndex); }
@@ -213,6 +223,12 @@
     // Returns the font to use for the given row
     Font getRowFont(int index);
 
+    // Moves the selection down/up one item, taking care of looping back to the
+    // first/last element if m_loopSelectionNavigation is true.
+    void selectPreviousRow();
+    void selectNextRow();
+
+
     // This is the index of the item marked as "selected" - i.e. displayed in the widget on the
     // page. 
     int m_originalIndex;
@@ -264,6 +280,8 @@
     TimeStamp m_lastCharTime;
 
     bool m_setTextOnIndexChange;
+
+    bool m_loopSelectionNavigation;
 };
 
 static PlatformMouseEvent constructRelativeMouseEvent(const PlatformMouseEvent& e,
@@ -488,6 +506,10 @@
     listBox()->setAcceptOnAbandon(value);
 }
 
+void PopupContainer::setLoopSelectionNavigation(bool value) {
+    listBox()->setLoopSelectionNavigation(value);
+}
+
 void PopupContainer::refresh()
 {
     listBox()->updateFromElement();
@@ -599,13 +621,18 @@
         abandon();  // may delete this
         return true;
     case VKEY_RETURN:
+        if (m_selectedIndex == -1)  {
+            m_popupClient->hidePopup();
+            // Don't eat the enter if nothing is selected.

[Matt Perry, 2009/01/21 22:38:09]

Seems strange to me that the enter would propagate up if the popup menu is open,
but if that's the behavior of other browsers, that's fine.

+            return false;
+        }
         acceptIndex(m_selectedIndex);  // may delete this
         return true;
     case VKEY_UP:
-        adjustSelectedIndex(-1);
+        selectPreviousRow();
         break;
     case VKEY_DOWN:
-        adjustSelectedIndex(1);
+        selectNextRow();
         break;
     case VKEY_PRIOR:
         adjustSelectedIndex(-m_visibleRows);
@@ -938,6 +965,40 @@
     return m_items[index]->type == TypeOption && m_popupClient->itemIsEnabled(index);
 }
 
+void PopupListBox::clearSelection() {
+    if (m_selectedIndex != -1) {
+        invalidateRow(m_selectedIndex);
+        m_selectedIndex = -1;
+    }
+}
+
+void PopupListBox::selectNextRow() {
+    if (!m_loopSelectionNavigation || m_selectedIndex != numItems() - 1) {
+        adjustSelectedIndex(1);
+        return;
+    }
+
+    // We are moving past the last item, no row should be selected.
+    clearSelection();
+}
+
+void PopupListBox::selectPreviousRow() {
+    if (!m_loopSelectionNavigation || m_selectedIndex > 0) {
+        adjustSelectedIndex(-1);
+        return;
+    }
+
+    if (m_selectedIndex == 0) {
+        // We are moving past the first item, clear the selection.
+        clearSelection();
+        return;
+    }
+
+    // No row are selected, jump to the last item.
+    selectIndex(numItems() - 1);
+    scrollToRevealSelection();
+}
+
 void PopupListBox::adjustSelectedIndex(int delta)
 {
     int targetIndex = m_selectedIndex + delta;