[gnome-shell/wip/pressure: 3/14] messageTray: Trigger the tray by downward pressure

[Jasper St. Pierre <jstpierre src gnome org>]

commit 89f66b1d7202109770e89ef315f4e2c96ead32b7
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Mon Jul 30 16:25:07 2012 -0300

    messageTray: Trigger the tray by downward pressure
    
    https://bugzilla.gnome.org/show_bug.cgi?id=677215

 js/ui/layout.js      |   79 ++++++++++++++++++++++++++++++++++++++++++-------
 js/ui/messageTray.js |   25 +++------------
 2 files changed, 72 insertions(+), 32 deletions(-)
---
diff --git a/js/ui/layout.js b/js/ui/layout.js
index 9c436b5..97285de 100644
--- a/js/ui/layout.js
+++ b/js/ui/layout.js
@@ -28,7 +28,8 @@ const LayoutManager = new Lang.Class({
         this._hotCorners = [];
         this._leftPanelBarrier = null;
         this._rightPanelBarrier = null;
-        this._trayBarrier = null;
+        this._vertTrayBarrier = null;
+        this._horizTrayBarrier = null;
 
         this._chrome = new Chrome(this);
 
@@ -48,7 +49,7 @@ const LayoutManager = new Lang.Class({
         this.trayBox = new St.BoxLayout({ name: 'trayBox' }); 
         this.addChrome(this.trayBox);
         this.trayBox.connect('allocation-changed',
-                             Lang.bind(this, this._updateTrayBarrier));
+                             Lang.bind(this, this._updateTrayBarriers));
 
         this.keyboardBox = new St.BoxLayout({ name: 'keyboardBox',
                                               reactive: true,
@@ -202,20 +203,37 @@ const LayoutManager = new Lang.Class({
         }
     },
 
-    _updateTrayBarrier: function() {
+    _updateTrayBarriers: function() {
         let monitor = this.bottomMonitor;
 
-        if (this._trayBarrier)
-            this._trayBarrier.deactivate();
+        if (this._vertTrayBarrier)
+            this._vertTrayBarrier.deactivate();
+        if (this._horizTrayBarrier)
+            this._horizTrayBarrier.deactivate();
+        if (this._horizTrayPressure)
+            this._horizTrayPressure.destroy();
 
         if (Main.messageTray) {
-            this._trayBarrier = new Meta.Barrier({ display: global.display,
-                                                   x1: monitor.x + monitor.width, y1: monitor.y + monitor.height - Main.messageTray.actor.height,
-                                                   x2: monitor.x + monitor.width, y2: monitor.y + monitor.height,
-                                                   directions: Meta.BarrierDirection.NEGATIVE_X });
-            this._trayBarrier.activate();
+            this._vertTrayBarrier = new Meta.Barrier({ display: global.display,
+                                                       x1: monitor.x + monitor.width, y1: monitor.y + monitor.height - Main.messageTray.actor.height,
+                                                       x2: monitor.x + monitor.width, y2: monitor.y + monitor.height,
+                                                       directions: Meta.BarrierDirection.NEGATIVE_X });
+
+            this._horizTrayBarrier = new Meta.Barrier({ display: global.display,
+                                                        x1: monitor.x, x2: monitor.x + monitor.width,
+                                                        y1: monitor.y + monitor.height, y2: monitor.y + monitor.height,
+                                                        directions: Meta.BarrierDirection.NEGATIVE_Y });
+
+            this._horizTrayPressure = new PressureBarrier(this._horizTrayBarrier, 100);
+            this._horizTrayPressure.connect('trigger', function() {
+                Main.messageTray.openTray();
+            });
+
+            this._vertTrayBarrier.activate();
+            this._horizTrayBarrier.activate();
         } else {
-            this._trayBarrier = null;
+            this._horizTrayBarrier = null
+            this._vertTrayBarrier = null;
         }
     },
 
@@ -991,5 +1009,42 @@ const Chrome = new Lang.Class({
         return false;
     }
 });
-
 Signals.addSignalMethods(Chrome.prototype);
+
+const PressureBarrier = new Lang.Class({
+    Name: 'TrayPressure',
+
+    _init: function(barrier, threshold) {
+        this._barrier = barrier;
+        this._threshold = threshold;
+
+        this._lastEventID = 0;
+        this._pressure = 0;
+
+        this._barrier.connect('hit', Lang.bind(this, this._onBarrierHit));
+    },
+
+    _getVelocity: function(event, barrier) {
+        if (barrier.y1 === barrier.y2)
+            return Math.abs(event.dx);
+        else
+            return Math.abs(event.dy);
+    },
+
+    _onBarrierHit: function(barrier, event) {
+        // Event IDs are incremented every time the user stops
+        // hitting the barrier. So, if the event ID switches,
+        // reset the current pressure counter.
+        if (this._lastEventId != event.event_id) {
+            this._pressure = 0;
+            this._lastEventId = event.event_id;
+        } else {
+            this._pressure += this._getVelocity(event, this._barrier);
+            if (this._pressure >= this._threshold) {
+                this.emit('trigger');
+                this._pressure = 0;
+            }
+        }
+    }
+});
+Signals.addSignalMethods(PressureBarrier.prototype);
diff --git a/js/ui/messageTray.js b/js/ui/messageTray.js
index f9d59b7..a29b3a2 100644
--- a/js/ui/messageTray.js
+++ b/js/ui/messageTray.js
@@ -1503,14 +1503,6 @@ const MessageTray = new Lang.Class({
         this._tweening = 0;
         this._windowsShifted = 0;
 
-        this._corner = new Clutter.Rectangle({ width: 1,
-                                               height: 1,
-                                               opacity: 0,
-                                               reactive: true });
-        this._corner.connect('enter-event', Lang.bind(this, this._onCornerEnter));
-        Main.layoutManager.trayBox.add_actor(this._corner);
-        Main.layoutManager.trackChrome(this._corner);
-
         Main.layoutManager.trayBox.add_actor(this.actor);
         this.actor.y = 0;
         Main.layoutManager.trackChrome(this.actor);
@@ -1554,24 +1546,12 @@ const MessageTray = new Lang.Class({
         this._chatSummaryItemsCount = 0;
     },
 
-    _onCornerEnter: function(actor, event) {
-        this._pointerInSummary = true;
-        this._updateState();
-    },
-
     _setSizePosition: function() {
         let monitor = Main.layoutManager.bottomMonitor;
         this._notificationBin.x = 0;
         this._notificationBin.width = monitor.width;
         this._summaryBin.x = 0;
         this._summaryBin.width = monitor.width;
-
-        if (Clutter.get_default_text_direction() == Clutter.TextDirection.RTL)
-            this._corner.x = 0;
-        else
-            this._corner.x = Main.layoutManager.trayBox.width - 1;
-
-        this._corner.y = Main.layoutManager.trayBox.height - 1;
     },
 
     contains: function(source) {
@@ -1694,6 +1674,11 @@ const MessageTray = new Lang.Class({
         this._updateState();
     },
 
+    openTray: function(actor, event) {
+        this._traySummoned = true;
+        this._updateState();
+    },
+
     toggle: function() {
         this._traySummoned = !this._traySummoned;
         Main.layoutManager.togglePanelStruts();