From 18c2f122114d48ec854c27bef002b64e2e3ea182 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=93scar=20Gonz=C3=A1lez=20Fern=C3=A1ndez?=
 <ogonzalez@igalia.com>
Date: Wed, 15 Jun 2011 18:05:16 +0200
Subject: [PATCH] Fix error when changing zoom

* adjust_height is removed from TaskList because the equivalent
  functionality is called from GanttPanel.

* GanttPanel.js receives the new methods for tracking the scroll. This
  should be simpler. It should be rewritten in the future.
---
 .../java/org/zkoss/ganttz/GanttPanel.java     |  1 +
 .../main/java/org/zkoss/ganttz/TaskList.java  |  6 --
 .../resources/web/js/ganttz/GanttPanel.js     | 57 ++++++++++++++++++-
 3 files changed, 55 insertions(+), 9 deletions(-)

diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/GanttPanel.java b/ganttzk/src/main/java/org/zkoss/ganttz/GanttPanel.java
index 2531894e7..d6534bec1 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/GanttPanel.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/GanttPanel.java
@@ -87,6 +87,7 @@ public class GanttPanel extends XulElement implements AfterCompose {
                 moveCurrentPositionScroll();
             }
 
+            // FIXME: this is quite awful, it should be simple
             @Override
             protected void moveCurrentPositionScroll() {
                 // get the previous data.
diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/TaskList.java b/ganttzk/src/main/java/org/zkoss/ganttz/TaskList.java
index fee048b38..81fdef61c 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/TaskList.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/TaskList.java
@@ -49,7 +49,6 @@ import org.zkoss.ganttz.timetracker.zoom.ZoomLevel;
 import org.zkoss.ganttz.util.Interval;
 import org.zkoss.ganttz.util.MenuBuilder;
 import org.zkoss.ganttz.util.MenuBuilder.ItemAction;
-import org.zkoss.zk.au.out.AuInvoke;
 import org.zkoss.zk.ui.event.Event;
 import org.zkoss.zk.ui.event.EventListener;
 import org.zkoss.zk.ui.ext.AfterCompose;
@@ -285,7 +284,6 @@ public class TaskList extends XulElement implements AfterCompose {
                     for (TaskComponent taskComponent : getTaskComponents()) {
                         taskComponent.zoomChanged();
                     }
-                    adjustZoomColumnsHeight();
                     adjustZoomPositionScroll();
                 }
             };
@@ -334,10 +332,6 @@ public class TaskList extends XulElement implements AfterCompose {
         return (GanttPanel) getParent();
     }
 
-    public void adjustZoomColumnsHeight() {
-        response("adjust_height", new AuInvoke(TaskList.this, "adjust_height"));
-    }
-
     private void adjustZoomPositionScroll() {
         getTimeTrackerComponent().movePositionScroll();
     }
diff --git a/ganttzk/src/main/resources/web/js/ganttz/GanttPanel.js b/ganttzk/src/main/resources/web/js/ganttz/GanttPanel.js
index 0942a3379..d6bb0c956 100644
--- a/ganttzk/src/main/resources/web/js/ganttz/GanttPanel.js
+++ b/ganttzk/src/main/resources/web/js/ganttz/GanttPanel.js
@@ -5,6 +5,7 @@ ganttz.GanttPanel = zk.$extends(zk.Widget,{
         xMouse : null,
         yMouse : null
     },
+    scrollDay: 0,
     $init : function(){
         this.$supers('$init', arguments);
         this.$class.setInstance(this);
@@ -61,9 +62,59 @@ ganttz.GanttPanel = zk.$extends(zk.Widget,{
     reScrollX : function(px){
         jq('#ganttpanel_inner_scroller_x').width(px);
     },
-    scroll_horizontal : function(value){
-        jq('#ganttpanel_scroller_x').scrollLeft(value);
+    /**
+     * Scrolls horizontally the ganttpanel when the zoom has resized the component
+     * width.
+     */
+    scroll_horizontal: function(daysDisplacement) {
+        scrollDay = daysDisplacement;
+    },
+
+    // FIXME: this is quite awful, it should be simple
+    update_day_scroll: function(previousPixelPerDay) {
+        this._fromPixelToDay(previousPixelPerDay);
+    },
+    move_scroll: function(diffDays, pixelPerDay) {
+        this._fromDayToPixel(diffDays,pixelPerDay);
+    },
+    _fromPixelToDay: function(previousPixelPerDay) {
+        var div1 = document.getElementById ("ganttpanel").parentNode;
+        var div2 = div1.parentNode;
+        var div3 = div2.parentNode;
+
+        var maxHPosition = div3.scrollWidth - div3.clientWidth;
+        if( maxHPosition > 0 ){
+            var proportion = div3.scrollWidth / maxHPosition;
+            var positionInScroll = div3.scrollLeft;
+            var positionInPx = positionInScroll * proportion;
+            if(positionInPx > 0){
+                var position = positionInPx / previousPixelPerDay;
+                var day = position;
+                this.scrollDay = position;
+            }
+        }
+    },
+    _fromDayToPixel: function(diffDays,pixelPerDay) {
+        var div1 = document.getElementById ("ganttpanel").parentNode;
+        var div2 = div1.parentNode;
+        var div3 = div2.parentNode;
+
+        var day = this.scrollDay;
+        day += parseInt(diffDays);
+        var newPosInPx = parseInt(day * pixelPerDay);
+        var maxHPosition = div3.scrollWidth - div3.clientWidth;
+        var newProportion = div3.scrollWidth / maxHPosition;
+        if( newProportion > 0){
+            var newPosInScroll = newPosInPx / newProportion;
+            if(newPosInScroll < 0){
+                newPosInScroll = 0;
+            }
+            div1.scrollLeft = newPosInScroll;
+            div2.scrollLeft = newPosInScroll;
+            div3.scrollLeft = newPosInScroll;
+        }
     }
+
 },{
     getInstance : function(){
         return this._instance;
@@ -71,4 +122,4 @@ ganttz.GanttPanel = zk.$extends(zk.Widget,{
     setInstance : function(instance){
         this._instance = instance;
     }
-});
\ No newline at end of file
+});