From 15de9f93ef09f9e540121d68ee51bcab6ebe19c0 Mon Sep 17 00:00:00 2001
From: Ruben Dashyan <ruben.dashyan@numworks.com>
Date: Thu, 14 Feb 2019 16:57:44 +0100
Subject: [PATCH] [escher/scroll_view] Implement Decorator::indicatorAtIndex
 explicitly

Instead of using pointer arithmetic
---
 escher/include/escher/scroll_view.h | 10 ++--------
 escher/src/scroll_view.cpp          | 28 ++++++++++++++++++++++++++--
 2 files changed, 28 insertions(+), 10 deletions(-)

diff --git a/escher/include/escher/scroll_view.h b/escher/include/escher/scroll_view.h
index cc680eec6..8fd79e7d6 100644
--- a/escher/include/escher/scroll_view.h
+++ b/escher/include/escher/scroll_view.h
@@ -46,10 +46,7 @@ public:
   public:
     BarDecorator();
     int numberOfIndicators() const override { return 2; }
-    View * indicatorAtIndex(int index) override {
-      assert(0 < index && index <= numberOfIndicators());
-      return &m_verticalBar + (index-1);
-    }
+    View * indicatorAtIndex(int index) override;
     KDRect layoutIndicators(KDSize content, KDPoint offset, KDRect frame) override;
     ScrollViewVerticalBar * verticalBar() { return &m_verticalBar; }
     ScrollViewHorizontalBar * horizontalBar() { return &m_horizontalBar; }
@@ -64,10 +61,7 @@ public:
   public:
     ArrowDecorator();
     int numberOfIndicators() const override { return 4; }
-    View * indicatorAtIndex(int index) override {
-      assert(0 < index && index <= numberOfIndicators());
-      return &m_topArrow + (index-1);
-    }
+    View * indicatorAtIndex(int index) override;
     KDRect layoutIndicators(KDSize content, KDPoint offset, KDRect frame) override;
     void setBackgroundColor(KDColor c) override;
   private:
diff --git a/escher/src/scroll_view.cpp b/escher/src/scroll_view.cpp
index 76dcf9bbd..832ac6f4c 100644
--- a/escher/src/scroll_view.cpp
+++ b/escher/src/scroll_view.cpp
@@ -130,6 +130,16 @@ ScrollView::BarDecorator::BarDecorator() :
 {
 }
 
+View * ScrollView::BarDecorator::indicatorAtIndex(int index) {
+  switch(index) {
+    case 1:
+      return &m_verticalBar;
+    default:
+      assert(index == 2);
+      return &m_horizontalBar;
+  }
+}
+
 KDRect ScrollView::BarDecorator::layoutIndicators(KDSize content, KDPoint offset, KDRect frame) {
   KDCoordinate hBarFrameBreadth = m_barsFrameBreadth * m_horizontalBar.update(
     content.width(),
@@ -162,6 +172,20 @@ ScrollView::ArrowDecorator::ArrowDecorator() :
 {
 }
 
+View * ScrollView::ArrowDecorator::indicatorAtIndex(int index) {
+  switch(index) {
+    case 1:
+      return &m_topArrow;
+    case 2:
+      return &m_rightArrow;
+    case 3:
+      return &m_bottomArrow;
+    default:
+      assert(index == 4);
+      return &m_leftArrow;
+  }
+}
+
 KDRect ScrollView::ArrowDecorator::layoutIndicators(KDSize content, KDPoint offset, KDRect frame) {
   KDSize arrowSize = KDFont::LargeFont->glyphSize();
   KDCoordinate topArrowFrameBreadth = arrowSize.height() * m_topArrow.update(0 < offset.y());
@@ -193,8 +217,8 @@ KDRect ScrollView::ArrowDecorator::layoutIndicators(KDSize content, KDPoint offs
 }
 
 void ScrollView::ArrowDecorator::setBackgroundColor(KDColor c) {
-  for (int i = 0; i < numberOfIndicators(); i++) {
-    (&m_topArrow + i)->setBackgroundColor(c);
+  for (int index = 1; index <= numberOfIndicators(); index++) {
+    static_cast<ScrollViewArrow *>(indicatorAtIndex(index))->setBackgroundColor(c);
   }
 }