Fix display switching for extended displays.

chromeos/display/output_configurator.cc

Index: chromeos/display/output_configurator.cc
diff --git a/chromeos/display/output_configurator.cc b/chromeos/display/output_configurator.cc
index 60013092234cbe9ba6612111b451f5159126c88e..a22937364a11cc47554c1ae5fd1319b77af45874 100644
--- a/chromeos/display/output_configurator.cc
+++ b/chromeos/display/output_configurator.cc
@@ -659,9 +659,22 @@ State OutputConfigurator::InferCurrentState(Display* display,
   return state;
 }
 
-bool OutputConfigurator::CycleDisplayMode() {
+bool OutputConfigurator::CycleDisplayMode(bool extended_desktop_enabled) {
   VLOG(1) << "CycleDisplayMode";
   bool did_change = false;
+
+  // The next state to go into if the current state is dual primary.
+  State next_state_from_dual_primary = STATE_DUAL_SECONDARY_ONLY;
+  if (extended_desktop_enabled) {
+    if (mirror_supported_) {
+      next_state_from_dual_primary = STATE_DUAL_MIRROR;
+    } else {
+      // In case mirror is not supported, stay in the
+      // extended desktop primary display.
+      next_state_from_dual_primary = STATE_INVALID;
+    }
+  }

[Josh Horwich, 2012/07/26 00:18:26]

Would this be easier to follow if you just put it into the block for 'case
STATE_DUAL_PRIMARY_ONLY', e.g.
    case STATE_DUAL_PRIMARY_ONLY:
      new_state = extended_desktop_enabled ?
          (mirror_supported_ ? STATE_DUAL_MIRROR : STATE_INVALID) :
          STATE_DUAL_SECONDAY_ONLY;

[rkc, 2012/07/26 00:32:52]

The ?:'s seemed kinda ugly so I moved it in the switch but with if's.


On 2012/07/26 00:18:26, Josh Horwich wrote:

+
   if (is_running_on_chrome_os_) {
     // Rules:
     // - if there are 0 or 1 displays, do nothing and return false.
@@ -674,7 +687,7 @@ bool OutputConfigurator::CycleDisplayMode() {
         new_state = STATE_DUAL_PRIMARY_ONLY;
         break;
       case STATE_DUAL_PRIMARY_ONLY:
-        new_state = STATE_DUAL_SECONDARY_ONLY;
+        new_state = next_state_from_dual_primary;
         break;
       case STATE_DUAL_SECONDARY_ONLY:
         new_state = mirror_supported_ ?