sketch2.py

sketch2.py

'''
A very simple drawing 'app' that demonstrates
custom views and saving images to the camera roll.
'''

import ui
import photos
import console

# The PathView class is responsible for tracking
# touches and drawing the current stroke.
# It is used by SketchView.

class PathView (ui.View):
    def __init__(self, frame):
        self.frame = frame
        self.flex = 'WH'
        self.path = None
        self.action = None

    def touch_began(self, touch):
        x, y = touch.location
        self.path = ui.Path()
        self.path.line_width = 8.0
        self.path.line_join_style = ui.LINE_JOIN_ROUND
        self.path.line_cap_style = ui.LINE_CAP_ROUND
        self.path.move_to(x, y)

    def touch_moved(self, touch):
        x, y = touch.location
        self.path.line_to(x, y)
        self.set_needs_display()

    def touch_ended(self, touch):
        # Send the current path to the SketchView:
        if callable(self.action):
            self.action(self)
        # Clear the view (the path has now been rendered
        # into the SketchView's image view):
        self.path = None
        self.set_needs_display()

    def draw(self):
        if self.path:
            self.path.stroke()

# The main SketchView contains a PathView for the current
# line and an ImageView for rendering completed strokes.
# It also manages the 'Clear' and 'Save' ButtonItems that
# are shown in the title bar.

class SketchView (ui.View):
    def __init__(self, width=1024, height=1024):
        self.bg_color = 'white'
        iv = ui.ImageView(frame=(0, 0, width, height))
        pv = PathView(frame=self.bounds)
        pv.action = self.path_action
        self.add_subview(iv)
        self.add_subview(pv)
        self.image_view = iv

    def path_action(self, sender):
        path = sender.path
        old_img = self.image_view.image
        width, height = self.image_view.width, self.image_view.height
        with ui.ImageContext(width, height) as ctx:
            if old_img:
                old_img.draw()
            path.stroke()
            self.image_view.image = ctx.get_image()

    def clear_action(self, sender):
        self.image_view.image = None

    def save_action(self, sender):
        if self.image_view.image:
            # We draw a new image here, so that it has the current
            # orientation (the canvas is quadratic).
            with ui.ImageContext(self.width, self.height) as ctx:
                self.image_view.image.draw()
                img = ctx.get_image()
                photos.save_image(img)
                console.hud_alert('Saved')
        else:
            console.hud_alert('No Image', 'error')

v = ui.load_view()
v['imageview1'].image = ui.Image('Dog_Face')
save_button = ui.ButtonItem()
save_button.title = 'Save Image'
save_button.action = v['view1'].save_action
clear_button = ui.ButtonItem()
clear_button.title = 'Clear'
clear_button.tint_color = 'red'
clear_button.action = v['view1'].clear_action
v.right_button_items = [save_button, clear_button]
v.present('sheet')

sketch2.pyui

[
  {
    "class" : "View",
    "attributes" : {
      "background_color" : "RGBA(1.000000,1.000000,1.000000,1.000000)",
      "tint_color" : "RGBA(0.000000,0.478000,1.000000,1.000000)",
      "enabled" : true,
      "border_color" : "RGBA(0.000000,0.000000,0.000000,1.000000)",
      "flex" : ""
    },
    "frame" : "{{0, 0}, {473, 489}}",
    "selected" : false,
    "nodes" : [
      {
        "class" : "ImageView",
        "attributes" : {
          "class" : "ImageView",
          "name" : "imageview1",
          "uuid" : "AC3FE861-965E-48E2-93AF-C0DA6A7BE69B",
          "frame" : "{{187, 195}, {100, 100}}",
          "border_width" : 1,
          "corner_radius" : 0
        },
        "frame" : "{{81, 28}, {257, 162}}",
        "selected" : true,
        "nodes" : [

        ]
      },
      {
        "class" : "View",
        "attributes" : {
          "name" : "view1",
          "corner_radius" : 0,
          "border_width" : 1,
          "class" : "View",
          "frame" : "{{187, 195}, {100, 100}}",
          "custom_class" : "SketchView",
          "uuid" : "1CAADA59-CDE0-4D70-8398-6DF93E27DAF9"
        },
        "frame" : "{{79, 243}, {259, 216}}",
        "selected" : false,
        "nodes" : [

        ]
      }
    ]
  }
]