I want to enhance usability of my Python-Kivy program. In the following program example, I want to allow users to operate it even if they don't have mouse. (by keyboard input.)
(1) In the first dialog (MyLayout2), user input in Textbox easily as the textbox has focus
(2) Hit Enter keyboard key to go to next dialog (MyLayout1)
(3) Hit Enter keyboard key to go to (1) (MyLayout2 again)
However in the 2nd (1), after (3), the focus of Textbox is lost. Any idea how to cope with this problem?
Main.py
from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.properties import NumericProperty
from kivy.uix.gridlayout import GridLayout
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.uix.textinput import TextInput
from kivy.core.window import Window
sm = ScreenManager()
class MyLayout1(BoxLayout):
pass
class MyLayout2(BoxLayout):
pass
class MyScreen(Screen):
dialog_number = 0
def __init__(self, **kwargs):
super(MyScreen, self).__init__(**kwargs)
self.gridlayout = None
self.gridlayout = MyLayout2()
self.add_widget(self.gridlayout)
Window.bind(on_key_down=self._keydown)
def _keydown(self,*args):
if (args[2] == 40):
if self.dialog_number == 0:
self.button2_clicked()
elif self.dialog_number == 1:
self.button1_clicked()
def _create_layout(self):
if self.gridlayout is not None:
self.remove_widget(self.gridlayout)
self.add_widget(self.gridlayout)
def button1_clicked(self, *args):
if self.gridlayout is not None:
self.remove_widget(self.gridlayout)
self.gridlayout = MyLayout2()
self.add_widget(self.gridlayout)
self.dialog_number = 0
def button2_clicked(self, *args):
if self.gridlayout is not None:
self.remove_widget(self.gridlayout)
self.gridlayout = MyLayout1()
self.add_widget(self.gridlayout)
self.dialog_number = 1
def find_instance(self, layout):
c = None
for c in list(self.children):
if isinstance(c, layout):
break
return c
class myApp(App):
def build(self):
self.anschoi = MyScreen(name = 'anschoi')
sm.add_widget(self.anschoi)
sm.current = 'anschoi'
return sm
if __name__ == '__main__':
myApp().run()
my.kv
<MyScreen>:
BoxLayout:
orientation: 'vertical'
padding: 10,40,10,40
spacing: 40
<MyLayout1>:
Button1:
id: btn1
text: 'OK or ENTER key'
on_release: root.parent.button1_clicked()
<MyLayout2>:
txtinput: txtinput
orientation: 'vertical'
TextInput:
id: txtinput
text: ''
multiline: False
focus: True
button2:
id:Button2
text: 'OK or ENTER key'
on_release: root.parent.button2_clicked()
<Button0#Button>:
<Button1#Button>:
<button2#Button>:
This is exactly the same problem as your previous question. Just change:
Window.bind(on_key_down=self._keydown)
to:
Window.bind(on_key_up=self._keydown)
Again, to avoid the on_key_up event (that almost always follows a on_key_down event) stealing the focus from your TextInput.
Related
After performing an operation, for example, receiving text and closing the window, when opening the window in the text field text.
It is necessary that after closing the mdDialog window, the text is erased. I manage to save it, but in the string method. It must be erased by pressing the button and closing.
from kivy.lang import Builder
from kivymd.app import MDApp
from kivymd.uix.button import MDFlatButton
from kivymd.uix.dialog import MDDialog
from kivymd.uix.boxlayout import BoxLayout
KV = '''
<Content>
tes:tes
orientation: 'vertical'
spacing: '12dp'
size_hint_y: None
height: '120dp'
MDTextField:
id:tes
on_text:app.inputs(self)
MDFloatLayout:
MDFloatingActionButton:
icon:'plus'
pos_hint:{'center_y': .1, 'center_x':.5}
on_release:app.new()
'''
class Content(BoxLayout):
pass
class General(MDApp):
dialog=None
def build(self):
return Builder.load_string(KV)
def inputs(self, event):
self.txt = event.text
print(self.txt)
def no(self, event):
event.text=''
self.dialog.dismiss()
def yes(self, event):
event.text=''
self.dialog.dismiss()
def new(self):
if not self.dialog:
self.dialog = MDDialog(
type='custom',
content_cls=Content(),
buttons = [
MDFlatButton(text='Отмена', text_color=self.theme_cls.primary_color, on_release=self.no),
MDFlatButton(text='Добавить',text_color=self.theme_cls.primary_color, on_press=self.yes),
]
)
self.dialog.open()
General().run()
Good day.
I recommend you create text_field_text = StringProperty("My Default String") in your App class and let the widget.text = app.text_field_text.
From there, you could clear your app string property with the callback function.
Below is the whole (test) app written with Kivy.
This is something like app preview application:
user enters a text of kv markup (see variable self.kv) and a text of classes (see variable self.text). Then he clicks the "preview" button and sees the result on the right side of the application.
Loading kv is implemented using kivy Builder.load_string(). Class loading is implemented using exec(, globals()).
The main problem is that for some reason I get the following error when I click on the preview button for the third time (the first 2 clicks work without errors):
TypeError: super(type, obj): obj must be an instance or subtype of type
The error can be because of exec(), (without exec I don’t get this error).
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.button import Button
KV = '''
BoxLayout:
BoxLayout:
orientation: 'vertical'
CodeEd
id: code_editor
Button:
text: 'Preview'
on_release: app.preview()
Preview:
id: preview_area
<CodeEd#TextInput>
text: app.text
<Preview#RelativeLayout>
'''
class MyApp(App):
def build(self):
self._kv_filename = 'KvEditor_internal.' + str(self.uid)
self.text = '''
class MyButton(Button):
def on_touch_down(self, touch):
if self.collide_point(*touch.pos):
print (333)
super(MyButton, self).on_touch_down(touch)
'''
self.kv = 'MyButton'
self.root = Builder.load_string(KV)
def preview(self):
preview_area = self.root.ids.preview_area
#if 'MyButton' in globals():
# del globals()['MyButton']
#print ('===================')
#print ([i for i in dict(globals())])
try:
exec(self.text, globals())
except:
print ('some error when exec class ')
Builder.unload_file(self._kv_filename)
try:
preview_area.add_widget(Builder.load_string(self.kv, filename=self._kv_filename))
except Exception as e:
print (e.message if getattr(e, r"message", None) else str(e))
MyApp().run()
How to solve this problem?
Question - Preview area is RelativeLayout
It seems to work, but could you edit or add an example, please? I do
not need the number of buttons in the preview area increased. I just
want every time after pressing "Preview", in the preview area I have
content that just reflects the current text of self.kv and self.text.
Example
The following example has most of the enhancements applied and the Preview area is a RelativeLayout.
main.py
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.button import Button
from kivy.properties import NumericProperty, StringProperty
from kivy.factory import Factory
KV = '''
BoxLayout:
BoxLayout:
orientation: 'vertical'
CodeEd
id: code_editor
Button:
text: 'Preview'
on_release: app.preview()
Preview:
id: preview_area
<CodeEd#TextInput>
text: app.text
<Preview#RelativeLayout>
'''
class MyApp(App):
text = StringProperty('')
previous_text = StringProperty('')
def build(self):
self._kv_filename = 'KvEditor_internal.' + str(self.uid)
self.text = '''
class MyButton(Button):
def on_touch_down(self, touch):
if self.collide_point(*touch.pos):
print (333)
return super(Button, self).on_touch_down(touch)
'''
self.previous_text = self.text
self.kv = 'MyButton'
self.root = Builder.load_string(KV)
def preview(self):
preview_area = self.root.ids.preview_area
self.text = self.root.ids.code_editor.text
try:
# Class loading is implemented using exec(, globals())
exec(self.text, globals())
except:
print('some error when exec class ')
Builder.unload_file(self._kv_filename)
try:
# check for code changes
if self.text != self.previous_text:
Factory.unregister(self.kv)
Factory.register(self.kv, cls=globals()[self.kv])
total_children = len(preview_area.children)
preview_area.clear_widgets()
for child in range(total_children):
preview_area.add_widget(Builder.load_string(self.kv, filename=self._kv_filename))
self.previous_text = self.text
preview_area.add_widget(Builder.load_string(self.kv, filename=self._kv_filename))
except Exception as e:
print(e.message if getattr(e, r"message", None) else str(e))
MyApp().run()
Output
Question 1 - TypeError
TypeError: super(type, obj): obj must be an instance or subtype of
type
Solution - TypeError
There are two solutions to the TypeError.
Method 1
Replace super(MyButton, self).on_touch_down(touch) with return False
Method 2
Replace super(MyButton, self).on_touch_down(touch) with return super(Button, self).on_touch_down(touch)
Question 2 - Support code changes to MyButton class
What if MyButton class exists, but I want to make changes to this
class, for example change some of its methods, and so on?
Solution - Support code changes to MyButton class
In order to support code changes to MyButton class, the following enhancements are required:
Add import statement for Kivy Properties, from kivy.properties import NumericProperty, StringProperty
Add import statement for Kivy Factory object, from kivy.factory import Factory
Add a new class attribute, previous_text of type, StringProperty to keep track of code changes.
Initialize self.previous_text
Update self.text when method preview() is invoked.
Check for code changes
Unregister previous class MyButton using Kivy Factory
Register new class MyButton using Kivy Factory
Save the total number of MyButton added
Remove previously added MyButton using clear_widgets(). If previously added MyButtons are not removed, it will not have the functionality of the new features/code changes.
Use for loop to re-add previously added MyButton with the new functionality / features.
Assign new code changes, self.text to self.previous_text
Snippets
from kivy.properties import NumericProperty, StringProperty
from kivy.factory import Factory
from kivy.logger import Logger
...
class MyApp(App):
i = NumericProperty(0)
text = StringProperty('')
previous_text = StringProperty('')
def build(self):
...
self.text = '''
...
return True # consumed on_touch_down & don't propagate
# return False
return super(Button, self).on_touch_down(touch)
'''
self.previous_text = self.text
...
def preview(self):
preview_area = self.root.ids.preview_area
self.text = self.root.ids.code_editor.text
...
try:
# check for code changes
if self.text != self.previous_text:
Factory.unregister(self.kv)
Factory.register(self.kv, cls=globals()[self.kv])
total_children = len(preview_area.children)
preview_area.clear_widgets()
for child in range(total_children):
btn = Builder.load_string(self.kv, filename=self._kv_filename)
btn.text = str(child + 1)
preview_area.add_widget(btn)
self.previous_text = self.text
Example
The following example illustrates a code editor supporting code changes to MyButton class, and MyButton widgets are added into a GridLayout.
main.py
from kivy.app import App
from kivy.lang import Builder
from kivy.properties import NumericProperty, StringProperty
from kivy.uix.button import Button
from kivy.logger import Logger
from kivy.factory import Factory
KV = '''
BoxLayout:
BoxLayout:
orientation: 'vertical'
CodeEd
id: code_editor
Button:
text: 'Preview'
on_release: app.preview()
Preview:
id: preview_area
<CodeEd#TextInput>:
text: app.text
<Preview#GridLayout>:
cols: 3
'''
class MyApp(App):
i = NumericProperty(0)
text = StringProperty('')
previous_text = StringProperty('')
def build(self):
self._kv_filename = 'KvEditor_internal.' + str(self.uid)
self.text = '''
class MyButton(Button):
def on_touch_down(self, touch):
if self.collide_point(*touch.pos):
print(f"touch.pos={touch.pos}")
print(f"Button.text={self.text}")
return True # consumed on_touch_down & don't propagate
# return False
return super(Button, self).on_touch_down(touch)
'''
self.previous_text = self.text
self.kv = 'MyButton'
self.root = Builder.load_string(KV)
def preview(self):
preview_area = self.root.ids.preview_area
self.text = self.root.ids.code_editor.text
try:
# Class loading is implemented using exec(, globals())
exec(self.text, globals())
except Exception as msg:
print('\nException: some error when exec class ')
Logger.error("KivyApp: Exception: some error when exec class")
print(msg)
quit()
Builder.unload_file(self._kv_filename)
try:
# check for code changes
if self.text != self.previous_text:
Factory.unregister(self.kv)
Factory.register(self.kv, cls=globals()['MyButton'])
total_children = len(preview_area.children)
preview_area.clear_widgets()
for child in range(total_children):
btn = Builder.load_string(self.kv, filename=self._kv_filename)
btn.text = str(child + 1)
preview_area.add_widget(btn)
self.previous_text = self.text
self.i += 1
btn = Builder.load_string(self.kv, filename=self._kv_filename)
btn.text = str(self.i)
preview_area.add_widget(btn)
except Exception as e:
print(e.message if getattr(e, r"message", None) else str(e))
MyApp().run()
Output
I am trying to figure out how to only change the screen direction animation in kivy for one certain button press(cancel button which should wipe right instead of left like a forward-navigating button.) Here is what I am doing currently to make this happen:
# Cancel Button
self.cancel = Button(text="Cancel", height=30, width=90,size_hint=(None, None),pos=(300, 350))
self.cancel.bind(on_release=self.BackFunction)
self.ids.float_web.add_widget(self.cancel)
def BackFunction(self, *args):
self.manager.transition.direction = 'right'
self.manager.current = ('input_sc')
I am wondering how to reset the direction to left after this animation happens. If I follow the screen change with
self.manager.transition.direction = 'left'
then it simply makes the direction left inside of BackFunction
Thanks
I think it's best to define the direction property each time you change thecurrent attribute. However, you can do what you want to do binding a function to on_complete event and unbind within the function itself:
Example:
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
kv_text='''\
#:import SlideTransition kivy.uix.screenmanager.SlideTransition
<MyScreenManager>:
transition: SlideTransition()
FirstScreen:
LastScreen:
<FirstScreen#Screen>:
name: 'first_sc'
BoxLayout:
Button:
text: 'Next'
on_release: root.next_screen()
<LastScreen#Screen>:
name: 'last_sc'
BoxLayout:
Button:
text: 'Previous'
on_release: root.previous_screen()
'''
class MyScreenManager(ScreenManager):
pass
class FirstScreen(Screen):
def __init__(self, **kwargs):
super(FirstScreen, self).__init__(**kwargs)
def next_screen(self, *args):
self.manager.current = 'last_sc'
class LastScreen(Screen):
def __init__(self, **kwargs):
super(LastScreen, self).__init__(**kwargs)
def previous_screen(self, *args):
self.manager.transition.direction = 'right'
self.manager.current = 'first_sc'
self.manager.transition.bind(on_complete=self.restart)
def restart(self, *args):
self.manager.transition.direction = 'left'
self.manager.transition.unbind(on_complete=self.restart)
class MySubApp(App):
def build(self):
return MyScreenManager()
def main():
Builder.load_string(kv_text)
app = MySubApp()
app.run()
if __name__ == '__main__':
main()
I tried to make by own coockie-clicker, so I creaded an kivy widget and declared an image of an coockie as part of it.
Everytime you click on the wiget, a counter goes up and the number is displayed on an label.
Everything went fine, after I got help here on stack overflow, but now I am faced with the problem, that the widet is to big, so even if I click on the right upper corner, to counter goes up, aldoug I do not clicked on the coockie.
Here is the sourcecode:
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.widget import Widget
from kivy.uix.label import Label
from kivy.core.window import Window
from kivy.clock import Clock
from kivy.animation import Animation
from kivy.core.text.markup import *
from kivy.uix.floatlayout import FloatLayout
from kivy.properties import NumericProperty
from kivy.properties import StringProperty
Builder.load_string('''
<Root>:
Kecks:
pos: 300, 300
size: 100, 100
<Kecks>:
Image:
pos: root.pos
id: my_image
source: root.weg
Label:
id: my_Label
font_size: 50
text: root.txt
center_x: 345
center_y: 200
''')
class Root(FloatLayout):
def __init__(self, *args, **kwargs):
super(Root, self).__init__(*args, **kwargs)
class Kecks(Widget):
count = NumericProperty(0)
amount = NumericProperty(1)
txt = StringProperty()
level = NumericProperty(1)
weg = StringProperty('piernik.png')
def __init__(self, *args, **kwargs):
super(Kecks, self).__init__(*args, **kwargs)
#self.txt = str(self.count)
Clock.schedule_interval(self.Update, 1/60.)
def Update(self, *args):
self.txt = str(self.count)
def on_touch_down(self, touch):
if self.collide_point(*touch.pos):
self.count += self.amount
class app(App):
def build(self):
Window.clearcolor = (10, 0, 0, 1)
return Root()
if __name__ == "__main__":
app().run()
The problem is you haven't defined your collide_points on which area you want that event to be triggered.
Consider if you want your collide_points on your my_image to trigger on_touch_down event, you need to adjust like this:
def on_touch_down(self, touch):
# to check if touch.pos collides on my_image
if self.ids.my_image.collide_point(*touch.pos):
self.count += self.amount
Also perhaps consider using pos_hint and size_hint as these will help you with consistency with your app running in different devices (size of screen, for instance), rather than using absolute size and/or position.
Hope this helps.
I'm trying to execute this:
from kivy.app import App
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.core.audio import SoundLoader,Sound
from kivy.lang import Builder
Builder.load_string('''
<MenuPage>:
BoxLayout:
orientation:'vertical'
Button:
text:'play'
on_press:root.plays()
Button:
text:'stop'
on_press:root.stops()
''')
class Music(Sound):
def __init__(self):
self.sound = SoundLoader.load('/home/hosein/Music/Man.mp3')
class MenuPage(Screen):
def __init__(self):
self.M = Music()
def plays(self):
self.M.play()
def stops(self):
self.M.stop()
music = Music()
sm = ScreenManager()
menu = MenuPage(name='menu')
sm.add_widget(menu)
class TestApp(App):
def build(self):
return sm
TestApp().run()
https://gist.github.com/daryasary/f69e1d0444ae70ff5296
There should be just two buttons to play or stop a song.
But it doesn't work. What is the solution?
Also, is there any way to make the play and stop buttons into a single button, where the first touch plays the song and the second stops it?
If you want to use one button, you could try using Kivy's ToggleButton and play music when the toggle button's state is 'down' and not play music when the state is 'normal'.
<MenuPage>:
BoxLayout:
orientation:'vertical'
ToggleButton:
id: music_button
text:'play'
on_press:root.play_or_stop()
''')
class MenuPage(Screen):
def __init__(self):
self.M = Music()
def play_or_stop(self):
if self.music_button.state == 'down':
self.music_button.text = "Stop"
self.M.play()
else:
self.music_button.text = "Play"
self.M.stop()
Or, you could use a regular button that sets a variable to either True or False each time it's pressed. You can then have this value determine whether the music plays or stops.
The problem is that you're using Sound wrong. You should not be subclassing Sound or trying to create a new instance directly.
SoundLoader.load returns a Sound instance created using one of the available audio providers - this should be used instead. Try something like this:
class MenuPage(Screen):
def __init__(self):
self.M = SoundLoader.load('/home/hosein/Music/Man.mp3')
def plays(self):
self.M.play()
def stops(self):
self.M.stop()
def toggle(self):
self.M.state = 'play' if self.M.state == 'stop' else 'play'
return self.M.state
it should be something like this:
from kivy.app import App
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.core.audio import SoundLoader,Sound
from kivy.lang import Builder
Builder.load_string('''
<MenuPage>:
BoxLayout:
orientation:'vertical'
Button:
text:'song'
on_press:root.plays()
''')
class MenuPage(Screen):
M = SoundLoader.load('/home/hosein/Music/Man.mp3')
def plays(self):
if MenuPage.M.state == 'stop':
MenuPage.M.play()
else:
MenuPage.M.stop()
sm = ScreenManager()
menu = MenuPage(name='menu')
sm.add_widget(menu)
class TestApp(App):
def build(self):
return sm
TestApp().run()