Appearance: Make color which items draggable

Create a ColorWhichListView class which impliments InitiateDrag()
to drag a color square out of the list view. You can then drop the
color anywhere that accepts a color drop. This allows you to drag
and drop colors between list items for example.

src/preferences/appearance/APRView.cpp

@@ -29,6 +29,7 @@
 #include "defs.h"
 #include "ColorPreview.h"
 #include "Colors.h"
+#include "ColorWhichListView.h"
 #include "ColorWhichItem.h"
 
 
@@ -74,7 +75,7 @@ APRView::APRView(const char* name)
 	LoadSettings();
 
 	// Set up list of color attributes
-	fAttrList = new BListView("AttributeList", B_SINGLE_SELECTION_LIST);
+	fAttrList = new ColorWhichListView("AttributeList");
 
 	fScrollView = new BScrollView("ScrollView", fAttrList, 0, false, true);
 	fScrollView->SetViewUIColor(B_PANEL_BACKGROUND_COLOR);

src/preferences/appearance/ColorWhichItem.cpp

@@ -82,17 +82,3 @@ ColorWhichItem::DrawItem(BView* owner, BRect frame, bool complete)
 	owner->SetHighColor(highColor);
 	owner->SetLowColor(lowColor);
 }
-
-
-color_which
-ColorWhichItem::ColorWhich(void)
-{
-	return fColorWhich;
-}
-
-
-void
-ColorWhichItem::SetColor(rgb_color color)
-{
-	fColor = color;
-}

src/preferences/appearance/ColorWhichItem.h

@@ -24,8 +24,11 @@ public:
 								rgb_color color);
 
 	virtual void			DrawItem(BView* owner, BRect frame, bool complete);
-			color_which		ColorWhich(void);
-			void			SetColor(rgb_color color);
+
+			color_which		ColorWhich() { return fColorWhich; };
+
+			rgb_color		Color() { return fColor; };
+			void			SetColor(rgb_color color) { fColor = color; };
 
 private:
 			color_which		fColorWhich;

src/preferences/appearance/ColorWhichListView.cpp

@@ -0,0 +1,106 @@
+/*
+ * Copyright 2016 Haiku, Inc. All rights reserved.
+ * Distributed under the terms of the MIT License.
+ *
+ * Authors:
+ *		John Scipione, jscipione@gmail.com
+ */
+
+
+#include "ColorWhichListView.h"
+
+#include <algorithm>
+
+#include <math.h>
+#include <stdio.h>
+
+#include <Bitmap.h>
+
+#include "ColorWhichItem.h"
+
+
+// golden ratio
+#ifdef M_PHI
+#	undef M_PHI
+#endif
+#define M_PHI 1.61803398874989484820
+
+
+//	#pragma mark - ColorWhichListView
+
+
+ColorWhichListView::ColorWhichListView(const char* name,
+	list_view_type type, uint32 flags)
+	:
+	BListView(name, type, flags)
+{
+}
+
+
+ColorWhichListView::~ColorWhichListView()
+{
+}
+
+
+bool
+ColorWhichListView::InitiateDrag(BPoint where, int32 index, bool wasSelected)
+{
+	ColorWhichItem* colorWhichItem
+		= dynamic_cast<ColorWhichItem*>(ItemAt(index));
+	if (colorWhichItem == NULL)
+		return false;
+
+	rgb_color color = colorWhichItem->Color();
+
+	char hexString[7];
+	sprintf(hexString, "#%.2X%.2X%.2X", color.red, color.green, color.blue);
+
+	BMessage message(B_PASTE);
+	message.AddData("text/plain", B_MIME_TYPE, &hexString, sizeof(hexString));
+	message.AddData("RGBColor", B_RGB_COLOR_TYPE, &color, sizeof(color));
+
+	float itemHeight = colorWhichItem->Height() - 5;
+	BRect rect(0.0f, 0.0f, roundf(itemHeight * M_PHI) - 1, itemHeight - 1);
+
+	BBitmap* bitmap = new BBitmap(rect, B_RGB32, true);
+	if (bitmap->Lock()) {
+		BView* view = new BView(rect, "", B_FOLLOW_NONE, B_WILL_DRAW);
+		bitmap->AddChild(view);
+
+		view->SetHighColor(B_TRANSPARENT_COLOR);
+		view->FillRect(view->Bounds());
+
+		++rect.top;
+		++rect.left;
+
+		view->SetHighColor(0, 0, 0, 100);
+		view->FillRect(rect);
+		rect.OffsetBy(-1.0f, -1.0f);
+
+		view->SetHighColor(std::min(255, (int)(1.2 * color.red + 40)),
+			std::min(255, (int)(1.2 * color.green + 40)),
+			std::min(255, (int)(1.2 * color.blue + 40)));
+		view->StrokeRect(rect);
+
+		++rect.left;
+		++rect.top;
+
+		view->SetHighColor((int32)(0.8 * color.red),
+			(int32)(0.8 * color.green),
+			(int32)(0.8 * color.blue));
+		view->StrokeRect(rect);
+
+		--rect.right;
+		--rect.bottom;
+
+		view->SetHighColor(color.red, color.green, color.blue);
+		view->FillRect(rect);
+		view->Sync();
+
+		bitmap->Unlock();
+	}
+
+	DragMessage(&message, bitmap, B_OP_ALPHA, BPoint(14.0f, 14.0f));
+
+	return true;
+}

src/preferences/appearance/ColorWhichListView.h

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2016 Haiku, Inc. All rights reserved.
+ * Distributed under the terms of the MIT License.
+ *
+ * Authors:
+ *		John Scipione, jscipione@gmail.com
+ */
+#ifndef COLORWHICH_LIST_VIEW_H
+#define COLORWHICH_LIST_VIEW_H
+
+
+#include <ListView.h>
+
+
+class ColorWhichListView : public BListView
+{
+public:
+								ColorWhichListView(const char* name,
+									list_view_type type
+										= B_SINGLE_SELECTION_LIST,
+									uint32 flags = B_WILL_DRAW
+										| B_FRAME_EVENTS | B_NAVIGABLE);
+	virtual						~ColorWhichListView();
+
+	virtual	bool				InitiateDrag(BPoint where, int32 index,
+									bool wasSelected);
+};
+
+#endif	// COLORWHICH_LIST_VIEW_H

src/preferences/appearance/Jamfile

@@ -20,6 +20,7 @@ Preference Appearance :
 	ColorPreview.cpp
 	Colors.cpp
 	ColorWhichItem.cpp
+	ColorWhichListView.cpp
 
 	# These are currently disabled while everything else is being worked on
 	#CurView.cpp