Merge pull request #93 from LucasSilvaFerreira/master

Drag and drop example

Author: martinRenou

examples/drag_and_drop_example.ipynb

@@ -0,0 +1,153 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": 96,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "application/vnd.jupyter.widget-view+json": {
+       "model_id": "00466ac5fda94b54807244ade58dd848",
+       "version_major": 2,
+       "version_minor": 0
+      },
+      "text/plain": [
+       "Canvas(height=600, width=600)"
+      ]
+     },
+     "metadata": {},
+     "output_type": "display_data"
+    }
+   ],
+   "source": [
+    "from ipycanvas import Canvas, hold_canvas\n",
+    "\n",
+    "canvas = Canvas(width=600, height=600)\n",
+    "canvas.fill_style = '#584f4e'\n",
+    "canvas.fill_rect(0, 0, 600, 600)\n",
+    "\n",
+    "\n",
+    "\n",
+    "objects_to_draw = []\n",
+    "class Square_obj():\n",
+    "    def __init__(self, x,y, width=100, height=40):\n",
+    "        self.x = x\n",
+    "        self.y = y\n",
+    "        self.width = width\n",
+    "        self.height = height\n",
+    "        self.selected = False\n",
+    "        objects_to_draw.append(self)\n",
+    "        \n",
+    "        \n",
+    "        \n",
+    "    def set_x_y(self,x_in,y_in)  :\n",
+    "        self.x = x_in\n",
+    "        self.y = y_in\n",
+    "    \n",
+    "    def draw(self):\n",
+    "        \n",
+    "        canvas.fill_style = '#38a8a4'\n",
+    "        canvas.fill_rect(self.x - (self.width*0.5), self.y - (self.height) , self.width, self.height)\n",
+    "        if self.selected:\n",
+    "            canvas.fill_style = '#9dcea6'\n",
+    "        else:\n",
+    "            canvas.fill_style = '#dee7bc'\n",
+    "        canvas.fill_rect(self.x - (self.width*0.5), self.y - (self.height*0.5) , self.width, self.height)\n",
+    "\n",
+    "        \n",
+    "        \n",
+    "    def is_selected(self,x_in, y_in):\n",
+    "        x_coord = self.x - (self.width*0.5)\n",
+    "        y_coord = self.y - (self.height*0.5)\n",
+    "\n",
+    "        if x_in > x_coord and x_in < (x_coord+ self.width) and  y_in > y_coord  and y_in < (y_coord  + self.height):\n",
+    "            \n",
+    "            self.set_selected(True)\n",
+    "            return True\n",
+    "        else:\n",
+    "            self.set_selected(False)\n",
+    "            return False\n",
+    "    \n",
+    "    def set_selected(self,state):\n",
+    "        self.selected = state\n",
+    "\n",
+    "\n",
+    "def canvas_restart():\n",
+    "    canvas.clear()\n",
+    "    canvas.fill_style = '#584f4e'\n",
+    "    canvas.fill_rect(0, 0, 600, 600)\n",
+    "\n",
+    "\n",
+    "\n",
+    "def handle_mouse_down(x, y):\n",
+    "    if [o for o in objects_to_draw if o.selected]:\n",
+    "        [o.set_selected(False) for o in objects_to_draw if o.selected]\n",
+    "        return False\n",
+    "    \n",
+    "    \n",
+    "    check_bool_pos = list(set([check_region.is_selected(x,y) for check_region in objects_to_draw]))\n",
+    "    if len(check_bool_pos)== 1:\n",
+    "        if check_bool_pos[0] == False:  \n",
+    "            s = Square_obj(x,y)\n",
+    "            s.set_selected(False)\n",
+    "            s.draw()\n",
+    "            \n",
+    "        else:\n",
+    "            canvas_restart()\n",
+    "            [o.draw() for o in objects_to_draw]\n",
+    "            \n",
+    "            \n",
+    "    if len(check_bool_pos)== 0:\n",
+    "        s = Square_obj(x,y) \n",
+    "        s.set_selected(False)\n",
+    "        s.draw()\n",
+    "    \n",
+    "\n",
+    "def handle_mouse_move(x, y):    \n",
+    "    if [o for o in objects_to_draw if o.selected]:\n",
+    "        with hold_canvas(canvas):\n",
+    "            [o for o in objects_to_draw if o.selected][-1].set_x_y(x,y)\n",
+    "            canvas_restart()\n",
+    "            [o.draw() for o in objects_to_draw]\n",
+    "\n",
+    "\n",
+    "    \n",
+    "    \n",
+    "canvas.on_mouse_down(handle_mouse_down)\n",
+    "canvas.on_mouse_move(handle_mouse_move)\n",
+    "\n",
+    "\n",
+    "canvas"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.7.3"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 2
+}