Use a static colors cache to preserve partition colors.

src/modules/partition/core/ColorUtils.cpp

@@ -27,6 +27,7 @@
 
 // Qt
 #include <QColor>
+#include <QMap>
 
 static const int NUM_PARTITION_COLORS = 5;
 static const int NUM_NEW_PARTITION_COLORS = 4;
@@ -49,6 +50,8 @@ static const QColor NEW_PARTITION_COLORS[ NUM_NEW_PARTITION_COLORS ] =
 static QColor FREE_SPACE_COLOR = "#777777";
 static QColor EXTENDED_COLOR = "#aaaaaa";
 
+static QMap< QString, QColor > s_partitionColorsCache;
+
 
 namespace ColorUtils
 {
@@ -75,6 +78,9 @@ colorForPartition( Partition* partition )
         return FREE_SPACE_COLOR;
     if ( partition->roles().has( PartitionRole::Extended ) )
         return EXTENDED_COLOR;
+    if ( s_partitionColorsCache.contains( partition->partitionPath() ) )
+        return s_partitionColorsCache[ partition->partitionPath() ];
+
     // No partition-specific color needed, pick one from our list, but skip
     // free space: we don't want a partition to change colors if space before
     // it is inserted or removed
@@ -102,6 +108,9 @@ colorForPartition( Partition* partition )
 
     if ( PMUtils::isPartitionNew( partition ) )
         return NEW_PARTITION_COLORS[ newColorIdx % NUM_NEW_PARTITION_COLORS ];
+
+    s_partitionColorsCache.insert( partition->partitionPath(),
+                                   PARTITION_COLORS[ colorIdx % NUM_PARTITION_COLORS ] );
     return PARTITION_COLORS[ colorIdx % NUM_PARTITION_COLORS ];
 }