My script allovs drawing lines by mouse. I want to delete last line by butoon Clear.(And sometimes delete gradually all lines) On stack overflow i found construction "self.ids.layout.remove_widget(self.ids.test)" How I create "self.ids.test" dynamically?. How must I modify this constuction for my script? Thank You.
from random import random
from kivy.app import App
from kivy.uix.widget import Widget
from kivy.uix.button import Button
from kivy.graphics import Color, Ellipse, Line
class MyPaintWidget(Widget):
def on_touch_down(self, touch):
color = (random(), 1, 1)
with self.canvas:
Color(*color, mode='hsv')
touch.ud['line'] = Line(points=(touch.x, touch.y))
def on_touch_move(self, touch):
touch.ud['line'].points += [touch.x, touch.y]
class MyPaintApp(App):
def build(self):
parent = Widget()
self.painter = MyPaintWidget()
clearbtn = Button(text='Clear', pos=(50,50))
clearbtn.bind(on_release=self.clear_canvas)
parent.add_widget(self.painter)
parent.add_widget(clearbtn)
return parent
def clear_canvas(self, obj):
pass
if __name__ == '__main__':
MyPaintApp().run()
When an instruction such as Line is added to canvas this is returned, then a possible solution is to store those instructions in a list, and then remove it through the remove() method of canvas:
class MyPaintWidget(Widget):
def __init__(self, *args, **kwargs):
Widget.__init__(self, *args, **kwargs)
self.lines = []
def on_touch_down(self, touch):
color = (random(), 1, 1)
with self.canvas:
Color(*color, mode='hsv')
l = Line(points=(touch.x, touch.y))
touch.ud['line'] = l
self.lines.append(l)
def on_touch_move(self, touch):
touch.ud['line'].points += [touch.x, touch.y]
class MyPaintApp(App):
def build(self):
parent = Widget()
self.painter = MyPaintWidget()
clearbtn = Button(text='Clear', pos=(50,50))
clearbtn.bind(on_release=self.clear_canvas)
parent.add_widget(self.painter)
parent.add_widget(clearbtn)
return parent
def clear_canvas(self, obj):
if len(self.painter.lines) != 0:
self.painter.canvas.remove(self.painter.lines[-1])
self.painter.lines = self.painter.lines[:-1]
if __name__ == '__main__':
MyPaintApp().run()
if you want to clean all the instructions you must use self.painter.canvas.clear()
Related
I have a screen with multiple widgets within it. I need to detect if the user clicked the label - 'home'
Whenever I click the screen the on_touch_down and on_touch_up is triggered. how can I determine the label that I clicked..
class WordScreen(Screen):
def __init__(self, **kwargs):
label_text = kwargs['label_text']
del kwargs['label_text']
super(WordScreen, self).__init__(**kwargs)
main_layout = BoxLayout(id='test', orientation='vertical')
navigation_layout = BoxLayout(orientation='horizontal',
size_hint_y=.1)
navigation_layout.add_widget(Label(text='home'))
navigation_layout.add_widget(Label(text='audio'))
navigation_layout.add_widget(Label(text='favorite'))
text_layout = BoxLayout(orientation='vertical')
text_layout.add_widget(Label(id='sight_text', text=label_text))
main_layout.add_widget(navigation_layout)
main_layout.add_widget(text_layout)
self.add_widget(main_layout)
def on_touch_down(self, touch):
self.initial = touch.x
def on_touch_up(self, touch):
print('on_touch_up - ', touch.x)
print(self.collide_point(*touch.pos))
print(touch.button)
s = None
try:
s = self.manager.get_screen('settings')
except ScreenManagerException:
pass
print('screen - ', s)
if s is not None:
self.manager.clear_widgets([s])
print('screen removed')
if touch.x < self.initial:
self.manager.transition = SlideTransition(direction="right")
self.manager.current = self.manager.next()
elif touch.x > self.initial:
self.manager.transition = SlideTransition(direction="right")
self.manager.current = self.manager.previous()
Based on link from John Anderson comment I created clickable Label.
from kivy.app import App
from kivy.uix.label import Label
from kivy.uix.behaviors import ButtonBehavior
class MyLabel(ButtonBehavior, Label):
def on_press(self):
print("press:", self.text)
def on_release(self):
print("release:", self.text)
class MyApp(App):
def build(self):
return MyLabel(text="Hello")
MyApp().run()
But problem can be that on_touch_down and on_touch_up may block other events and then even standard Button will not work. You may have to check on_touch_down and on_touch_up only in widget which doesn't need on_press, on_release
Probably it could be resolved using only on_touch_move without on_touch_down, on_touch_up
EDIT:
Minimal working code.
It uses clickable Label and on_touch_move without on_touch_down, on_touch_up to slide screen.
BTW: I use if touch.dx < -3: instead of if touch.dx < 0: to skip very small moves. I tested it only with mouse but for findgers it may need different value.
from kivy.uix.boxlayout import BoxLayout
from kivy.app import App
from kivy.uix.button import Button
from kivy.uix.label import Label
from functools import partial
from kivy.uix.screenmanager import ScreenManager, Screen, SlideTransition
from kivy.uix.behaviors import ButtonBehavior
class MyLabel(ButtonBehavior, Label):
def on_press(self):
print("pressed:", self.text)
def on_release(self):
print("release:", self.text)
class WordScreen(Screen):
def __init__(self, **kwargs):
label_text = kwargs['label_text']
del kwargs['label_text']
super(WordScreen, self).__init__(**kwargs)
main_layout = BoxLayout(id='test', orientation='vertical')
navigation_layout = BoxLayout(orientation='horizontal',
size_hint_y=.1)
navigation_layout.add_widget(MyLabel(text='home'))
navigation_layout.add_widget(MyLabel(text='audio'))
navigation_layout.add_widget(MyLabel(text='favorite'))
text_layout = BoxLayout(orientation='vertical')
#text_layout.add_widget(Label(id='sight_text', text=label_text))
text_layout.add_widget(Label(id='sight_text', text=self.name))
main_layout.add_widget(navigation_layout)
main_layout.add_widget(text_layout)
self.add_widget(main_layout)
def on_touch_move(self, touch):
#print('touch variable:\n', "\n".join(dir(touch)))
print('touch.dx:', touch.dx)
print('touch.dsx:', touch.dsx)
#print('touch.distance:', touch.distance)
#print('touch.move:', touch.move)
if touch.dx < -3: # using `touch.dx < 0` it slides even on very small moves
self.manager.transition = SlideTransition(direction="right")
self.manager.current = self.manager.next()
elif touch.dx > 3: # using `touch.dx > 0` it slides even on very small moves
self.manager.transition = SlideTransition(direction="right")
self.manager.current = self.manager.previous()
sm = ScreenManager()
sm.add_widget(WordScreen(name='menu', label_text="Example"))
sm.add_widget(WordScreen(name='settings', label_text="Example"))
class MyApp(App):
def build(self):
return sm
if __name__ == '__main__':
MyApp().run()
EDIT:
Problem with on_touch_down, on_touch_up which block on_press, on_release can be resolved using super() to execute original code on_touch_down, on_touch_up
def on_touch_down(self, touch):
# ... code ...
return super(WordScreen, self).on_touch_down(touch)
def on_touch_up(self, touch):
# ... code ...
return super(WordScreen, self).on_touch_up(touch)
Based on example in documentation: Events - Dispatching a Property event
I made a code where you can draw lines with a kivy canva and I wanted to add a Textinput. But the problem is that when I trie clicking on the Textinput, kivy wants to draw a line and it gives me an error :
" File "/myfolders/test.py", line 45, in on_touch_up
touch.ud['line'].points += [touch.x, touch.y]
KeyError: 'line' "
Here is my code :
from kivy.app import App
from kivy.uix.widget import Widget
from kivy.graphics import Color, Ellipse, Line, Rectangle
from kivy.uix.image import Image
from kivy.clock import Clock
from kivy.uix.textinput import TextInput
from time import sleep
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.scatter import Scatter
from kivy.uix.boxlayout import BoxLayout
from math import *
isLine=False
length=0
class MyBackground(Widget):
def __init__(self, **kwargs):
super(MyBackground, self).__init__(**kwargs)
with self.canvas:
self.bg = Rectangle(source='chouettes3.jpg', pos=self.pos, size=self.size)
self.bind(pos=self.update_bg)
self.bind(size=self.update_bg)
def update_bg(self, *args):
self.bg.pos = self.pos
self.bg.size = self.size
class MyPaintWidget(Widget):
def on_touch_down(self, touch):
#if self.collide_point(*touch.pos):
with self.canvas:
self.canvas.clear()
d=15
Rectangle(pos=(touch.x-d/2,touch.y-d/2),size=(d,d))
touch.ud['line'] = Line(points=(touch.x, touch.y), width=3)
def on_touch_up(self, touch):
#if self.collide_point(*touch.pos):
touch.ud['line'].points += [touch.x, touch.y]
points=touch.ud['line'].points
length=sqrt(((points[0]-points[2])**2)+((points[1]-points[3])**2))
print (length)
with self.canvas:
d=15
Rectangle(pos=(touch.x-d/2,touch.y-d/2),size=(d,d))
class MyPaintApp(App):
def build(self):
f = FloatLayout()
s = Scatter()
b = BoxLayout(orientation='vertical')
parent = MyBackground()
painter = MyPaintWidget(pos_hint={'x': 100, 'center_y': 100}, size_hint=(None, None))
textinput = TextInput(text='Hello world')
parent.add_widget(painter)
parent.add_widget(textinput)
f.add_widget(parent)
sleep(0.1)
return f
if __name__ == '__main__':
MyPaintApp().run()
I tried the self.collide_point technique, where something only works when you click on the widget in question but that just doesn't draw a line anymore.
Thanks in advance for your answers!
One problem is your use of the Widget class as a container for other Widgets. You should use a Layout class to contain other Widgets, otherwise, things like pos_hint have no effect. So I have modified your code to make MyBackground extend FloatLayout. Also, using collide_point() is a good idea, but usually, when you override a class method, you should also call the overridden method using super(). With that in mind, here is your modified code, that I think will work as you intended:
from kivy.app import App
from kivy.uix.widget import Widget
from kivy.graphics import Color, Line, Rectangle
from kivy.uix.textinput import TextInput
from kivy.uix.floatlayout import FloatLayout
from math import *
isLine=False
length=0
class MyBackground(FloatLayout):
def __init__(self, **kwargs):
super(MyBackground, self).__init__(**kwargs)
with self.canvas:
self.bg = Rectangle(source='chouettes3.jpg', pos=self.pos, size=self.size)
self.bind(pos=self.update_bg)
self.bind(size=self.update_bg)
def update_bg(self, *args):
self.bg.pos = self.pos
self.bg.size = self.size
class MyPaintWidget(Widget):
def on_touch_down(self, touch):
if self.collide_point(*touch.pos):
with self.canvas:
self.canvas.clear()
d=15
Color(1, 0, 0, 1)
Rectangle(pos=(touch.x-d/2,touch.y-d/2),size=(d,d))
touch.ud['line'] = Line(points=(touch.x, touch.y), width=3)
return super(MyPaintWidget, self).on_touch_down(touch)
def on_touch_up(self, touch):
if 'line' not in touch.ud:
return super(MyPaintWidget, self).on_touch_up(touch)
if self.collide_point(*touch.pos):
touch.ud['line'].points += [touch.x, touch.y]
points=touch.ud['line'].points
length=sqrt(((points[0]-points[2])**2)+((points[1]-points[3])**2))
print (length)
with self.canvas:
d=15
Rectangle(pos=(touch.x-d/2,touch.y-d/2),size=(d,d))
return super(MyPaintWidget, self).on_touch_up(touch)
class MyPaintApp(App):
def build(self):
parent = MyBackground()
painter = MyPaintWidget(pos_hint={'x':0., 'center_y':0.5}, size_hint=(1, 1))
self.textinput = TextInput(text='Hello world', pos=(0,0), size_hint=(0.1,0.1))
parent.add_widget(painter)
parent.add_widget(self.textinput)
return parent
if __name__ == '__main__':
MyPaintApp().run()
I have also eliminated some unused code in the build() method.
As the code stands, clicking in the TextInput will not start a new line, but you can end a line behind the TextInput. If you don't want that to happen, you can add a collision test in the on_touch_up() method to handle it as shown below:
def on_touch_up(self, touch):
if 'line' not in touch.ud:
return super(MyPaintWidget, self).on_touch_up(touch)
ti = App.get_running_app().textinput
if self.collide_point(*touch.pos) and not ti.collide_point(*touch.pos):
touch.ud['line'].points += [touch.x, touch.y]
points=touch.ud['line'].points
length=sqrt(((points[0]-points[2])**2)+((points[1]-points[3])**2))
print (length)
with self.canvas:
d=15
Rectangle(pos=(touch.x-d/2,touch.y-d/2),size=(d,d))
else:
self.canvas.clear()
return super(MyPaintWidget, self).on_touch_up(touch)
I have followed the widget tutorial for Kivy, but I cannot get the canvas to clear after painting (from their 'a simple paint app' tutorial), unless I resize the window after pressing the clear button. Please help. I am using kivy v1.10.1 and python v3.7.0. on windows 10 64-bit OS. Further, a widget in scatter mode leaves a trace when you drag to a new position, this also clears when resizing the window. See code below:
from random import random
from kivy.app import App
from kivy.uix.widget import Widget
from kivy.uix.button import Button
from kivy.graphics import Color, Ellipse, Line
class MyPaintWidget(Widget):
def on_touch_down(self, touch):
color = (random(), 1, 1)
with self.canvas:
Color(*color, mode='hsv')
d = 30.
Ellipse(pos=(touch.x - d / 2, touch.y - d / 2), size=(d, d))
touch.ud['line'] = Line(points=(touch.x, touch.y))
def on_touch_move(self, touch):
touch.ud['line'].points += [touch.x, touch.y]
class MyPaintApp(App):
def build(self):
parent = Widget()
self.painter = MyPaintWidget()
clearbtn = Button(text='Clear')
clearbtn.bind(on_release=self.clear_canvas)
parent.add_widget(self.painter)
parent.add_widget(clearbtn)
return parent
def clear_canvas(self, obj):
self.painter.canvas.clear()
if __name__ == '__main__':
MyPaintApp().run()
I'm trying to make a screen that has two rows, one of those rows are the actual game screen and the another one is a button to clear the table above. But the problem here is that the first row is blank when I run the app. That's the code that I am stuck till now:
import kivy
from kivy.app import App
from kivy.uix.screenmanager import Screen, ScreenManager
from kivy.uix.gridlayout import GridLayout
from kivy.uix.button import Button
kivy.require('1.9.2')
class VelhaGame(GridLayout, Screen):
def __init__(self, **kwargs):
super(VelhaGame, self).__init__(**kwargs)
self.cols = 3
self.rows = 3
self.font_size = 100
self.buttons = []
for i in range(9):
button = Button(text='', font_size=self.font_size)
button.bind(on_release=self.player_turn)
self.add_widget(button)
self.buttons.append(button)
self.player1 = True
def player_turn(self, button, *args):
if self.player1 and button.text == '':
self.player1 = False
button.text = 'X'
elif not self.player1 and button.text == '':
self.player1 = True
button.text = 'O'
class MainMenu(GridLayout, Screen):
def __init__(self, **kwargs):
super(MainMenu, self).__init__(**kwargs)
self.cols = 1
self.rows = 2
self.button_play = Button(text='PLAY', font_size=40)
self.button_play.bind(on_release=self.play)
self.add_widget(self.button_play)
self.button_exit = Button(text='EXIT', font_size=40)
self.button_exit.bind(on_release=self.exit)
self.add_widget(self.button_exit)
def play(self, *args):
screen_manager.current = 'velhaPage'
def exit(self, *args):
App.get_running_app().stop()
game_screen_manager = ScreenManager()
game_screen_manager.add_widget(VelhaGame(name='velhaGame'))
class VelhaScreen(GridLayout, Screen):
def __init__(self, **kwargs):
super(VelhaScreen, self).__init__(**kwargs)
self.rows = 2
self.add_widget(game_screen_manager)
self.clear_button = Button(text='Clear', font_size=40)
self.add_widget(self.clear_button)
screen_manager = ScreenManager()
screen_manager.add_widget(MainMenu(name='menu'))
screen_manager.add_widget(VelhaScreen(name='velhaPage'))
class VelhaGameApp(App):
def build(self):
return screen_manager
if __name__ == '__main__':
VelhaGameApp().run()
Do you know what I could do to accomplish this task?
The answer to you question, is "You cannot do that".
Screenmanager only shows one screen at a time.
you can read about that in the docs https://kivy.org/docs/api-kivy.uix.screenmanager.html
But to acheive something like you are trying to, you could do like this:
Instead of screens inside another screen, you could put the gridlayout, and button inside a vertical orientated boxlayout like this:
import kivy
from kivy.app import App
from kivy.uix.screenmanager import Screen, ScreenManager
from kivy.uix.gridlayout import GridLayout
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.button import Button
from kivy.properties import ListProperty
kivy.require('1.9.1')
class VelhaGame(Screen):
buttons = ListProperty([])
def __init__(self, **kwargs):
super(VelhaGame, self).__init__(**kwargs)
self.game_window = BoxLayout(orientation="vertical")
self.add_widget(self.game_window)
self.game_table = GridLayout(cols=3,rows=3)
for i in range(9):
button = Button(text='', font_size="100sp")
button.bind(on_release=self.player_turn)
self.game_table.add_widget(button)
self.buttons.append(button)
self.player1 = True
self.clear_button = Button(on_press=self.clear,text='Clear', font_size="40sp")
self.game_window.add_widget(self.game_table)
self.game_window.add_widget(self.clear_button)
def clear(self,*args):
for button in self.buttons:
button.text = ""
def player_turn(self, button, *args):
if self.player1 and button.text == '':
self.player1 = False
button.text = 'X'
elif not self.player1 and button.text == '':
self.player1 = True
button.text = 'O'
class MainMenu(GridLayout, Screen):
def __init__(self, **kwargs):
super(MainMenu, self).__init__(**kwargs)
self.cols = 1
self.rows = 2
self.button_play = Button(text='PLAY', font_size="40sp")
self.button_play.bind(on_release=self.play)
self.add_widget(self.button_play)
self.button_exit = Button(text='EXIT', font_size=40)
self.button_exit.bind(on_release=self.exit)
self.add_widget(self.button_exit)
def play(self, *args):
screen_manager.current = 'velhaPage'
def exit(self, *args):
App.get_running_app().stop()
screen_manager = ScreenManager()
screen_manager.add_widget(MainMenu(name='menu'))
screen_manager.add_widget(VelhaGame(name='velhaPage'))
class VelhaGameApp(App):
def build(self):
return screen_manager
if __name__ == '__main__':
VelhaGameApp().run()
I am trying to refactor the last code sample so that the Button is actually its own class with an on_release action. But my code is failing.
I want to not only refactor it (per my attempt below) but I also need to set the text of the Button to "Clear"
from random import random
from kivy.app import App
from kivy.uix.widget import Widget
from kivy.uix.button import Button
from kivy.graphics import Color, Ellipse, Line
class MyPaintWidget(Widget):
def on_touch_down(self, touch):
userdata = touch.ud
userdata['color'] = c = (random(), 1, 1)
with self.canvas:
Color(*c, mode='hsv')
d = 30
Ellipse(pos=(touch.x - d/2, touch.y - d/2), size=(d, d))
userdata['line'] = Line(points=(touch.x, touch.y))
def on_touch_move(self, touch):
touch.ud['line'].points += [touch.x, touch.y]
class ClearButton(Button):
def __init__(self, paint_widget):
self.paint_widget=paint_widget
def on_release(self, button):
self.paint_widget.canvas.clear()
class MyPaintApp(App):
def build(self):
parent = Widget()
painter = MyPaintWidget()
clearbtn = ClearButton(painter)
parent.add_widget(painter)
parent.add_widget(clearbtn)
return parent
if __name__ == '__main__':
MyPaintApp().run()
Without subclassing, you could just do:
class MyPaintWidget(Widget):
# ... put your previous methods here
def clear_canvas(self, *largs):
self.canvas.clear()
class MyPaintApp(App):
def build(self):
root = FloatLayout()
painter = MyPaintWidget()
cleanbtn.bind(on_release=self.painter.clear_canvas)
root.add_widget(painter)
root.add_widget(clearbtn)
return root
With subclassing, i would prefer to go with Kv langage:
from kivy.lang import Builder
Builder.load_string('''
<ClearButton>:
text: "Clear"
on_release: app.painter.canvas.clear()
''')
class ClearButton(Button):
pass
class MyPaintApp(App):
def build(self):
parent = Widget()
painter = MyPaintWidget()
clearbtn = ClearButton()
parent.add_widget(painter)
parent.add_widget(clearbtn)
return parent