如何制作图像并将其显示在下一页
How to make an image and display it on the next page
下午好，我使用 Python 和 Kivy 编写了一个简单的相机程序，但我就是拍不到照片。您需要拍摄 "ScreenThree" 的快照（将其保存在 phone 的内存中）并将生成的图像显示在 "ScreenFour" 上。
我用kivy.uix.camera显示摄像头，kivymd和kv创建界面。
android.permissions：互联网，相机，WRITE_EXTERNAL_STORAGE，READ_EXTERNAL_STORAGE
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.uix.camera import Camera
from kivymd.theming import ThemeManager
import time
Builder.load_string("""
#:import MDFillRoundFlatButton kivymd.button.MDFillRoundFlatButton
#:import MDIconButton kivymd.button.MDIconButton
<ScreenOne@Screen>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
MDFillRoundFlatButton:
color: [1,1,1,1]
text: "Перейти к созданию фото"
pos_hint: {'center_x':.50, 'center_y':.50}
on_press:
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_two'
<ScreenTwo@Screen>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
MDFillRoundFlatButton:
color: [1,1,1,1]
text: "Выбрать фон"
pos_hint: {'center_x':.50, 'center_y':.10}
on_press:
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_three'
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_one'
<ScreenThree@Screen>:
id: entry
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
Camera:
id: camera
index: 0
resolution: (1280,720)
play: True
MDFillRoundFlatButton:
text: "take photo"
pos_hint: {'center_x': 0.50, 'center_y': .10}
on_press:
root.capture() #TAKE PHOTO
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_four'
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_two'
<ScreenFour@Screen>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
# HERE I NEED TO DISPLAY THE IMAGE
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_three'
""")
class ScreenOne(Screen):
pass
class ScreenTwo(Screen):
theme_cls = ThemeManager()
theme_cls.primary_palette = 'Blue'
main_widget = None
class ScreenThree(Screen):
theme_cls = ThemeManager()
theme_cls.primary_palette = 'Blue'
main_widget = None
def capture(self):
camera = self.ids['camera']
timestr = time.strftime("%Y%m%d_%H%M%S")
photo = camera.export_to_png("IMG_{}.png".format(timestr))
print("Captured")
class ScreenFour(Screen):
pass
screen_manager = ScreenManager()
screen_manager.add_widget(ScreenOne(name="screen_one"))
screen_manager.add_widget(ScreenTwo(name="screen_two"))
screen_manager.add_widget(ScreenThree(name="screen_three"))
screen_manager.add_widget(ScreenFour(name="screen_four"))
class Interface(App):
def build(self):
return screen_manager
sample_app = Interface()
sample_app.run()
请告诉我，我该如何修改代码才能完成任务。
错误
Take photo
White screen
04-08 21:15:19.925 796 13801 E mm-camera: <STATS_AF ><ERROR> 959: af_spd_detect_process: ERROR! SPOT_LIGHT_FLAG =0!!! :AEC_grid = 256, BG_grid = 3072, ave luma = 0
04-08 21:15:19.933 835 902 W SurfaceFlinger: EventThread: dropping event (7673796e) for connection 0x7b332278c0
04-08 21:15:19.949 835 902 W SurfaceFlinger: EventThread: dropping event (7673796e) for connection 0x7b332278c0
04-08 21:15:19.959 796 13801 E mm-camera: <STATS_AF ><ERROR> 959: af_spd_detect_process: ERROR! SPOT_LIGHT_FLAG =0!!! :AEC_grid = 256, BG_grid = 3072, ave luma = 0
04-08 21:15:19.966 835 902 W SurfaceFlinger: EventThread: dropping event (7673796e) for connection 0x7b332278c0
04-08 21:15:19.983 835 902 W SurfaceFlinger: EventThread: dropping event (7673796e) for connection 0x7b332278c0
04-08 21:15:19.992 796 13801 E mm-camera: <STATS_AF ><ERROR> 959: af_spd_detect_process: ERROR! SPOT_LIGHT_FLAG =0!!! :AEC_grid = 256, BG_grid = 3072, ave luma = 0
04-08 21:15:19.999 835 902 W SurfaceFlinger: EventThread: dropping event (7673796e) for connection 0x7b332278c0
错误2
04-09 08:27:25.140 796 6243 E mm-camera: <STATS_AF ><ERROR> 959: af_spd_detect_process: ERROR! SPOT_LIGHT_FLAG =0!!! :AEC_grid = 256, BG_grid = 3072, ave luma = 0
04-09 08:27:25.146 835 902 W SurfaceFlinger: EventThread: dropping event (7673796e) for connection 0x7b32a54420
04-09 08:27:25.146 6164 6198 I python : Captured
04-09 08:27:25.147 6164 6198 I python : [ERROR ] [Image ] Error reading file IMG_20190409_082724.png
04-09 08:27:25.162 835 902 W SurfaceFlinger: EventThread: dropping event (7673796e) for connection 0x7b32a54420
04-09 08:27:25.175 796 6243 E mm-camera: <STATS_AF ><ERROR> 959: af_spd_detect_process: ERROR! SPOT_LIGHT_FLAG =0!!! :AEC_grid = 256, BG_grid = 3072, ave luma = 0
04-09 08:27:25.179 835 902 W SurfaceFlinger: EventThread: dropping event (7673796e) for connection 0x7b32a54420
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.uix.camera import Camera
from kivymd.theming import ThemeManager
import time
filename = ''
screenfour = ''
Builder.load_string("""
#:import MDFillRoundFlatButton kivymd.button.MDFillRoundFlatButton
#:import MDIconButton kivymd.button.MDIconButton
<ScreenOne@Screen>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
MDFillRoundFlatButton:
color: [1,1,1,1]
text: "Перейти к созданию фото"
pos_hint: {'center_x':.50, 'center_y':.50}
on_press:
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_two'
<ScreenTwo@Screen>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
MDFillRoundFlatButton:
color: [1,1,1,1]
text: "Выбрать фон"
pos_hint: {'center_x':.50, 'center_y':.10}
on_press:
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_three'
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_one'
<ScreenThree@Screen>:
id: entry
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
Camera:
id: camera
index: 0
resolution: (1280,720)
play: True
MDFillRoundFlatButton:
text: "take photo"
pos_hint: {'center_x': 0.50, 'center_y': .10}
on_press:
root.capture() #TAKE PHOTO
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_four'
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_two'
<ScreenFour@Screen>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
Image:
size: root.width, root.height
source: ''
id: imageWid
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_three'
""")
class ScreenOne(Screen):
pass
class ScreenTwo(Screen):
theme_cls = ThemeManager()
theme_cls.primary_palette = 'Blue'
main_widget = None
class ScreenThree(Screen):
theme_cls = ThemeManager()
theme_cls.primary_palette = 'Blue'
main_widget = None
def capture(self):
camera = self.ids['camera']
timestr = time.strftime("%Y%m%d_%H%M%S")
photo = camera.export_to_png("IMG_{}.png".format(timestr))
global filename, screenfour
filename = "IMG_{}.png".format(timestr)
print("Captured")
screenfour.update()
class ScreenFour(Screen):
def __init__(self, **kwargs):
super(ScreenFour, self).__init__(**kwargs)
global screenfour
screenfour = self
def update(self, *args):
global filename
imageWidget = self.ids['imageWid']
imageWidget.source = filename
screen_manager = ScreenManager()
screen_manager.add_widget(ScreenOne(name="screen_one"))
screen_manager.add_widget(ScreenTwo(name="screen_two"))
screen_manager.add_widget(ScreenThree(name="screen_three"))
screen_manager.add_widget(ScreenFour(name="screen_four"))
class Interface(App):
def build(self):
return screen_manager
sample_app = Interface()
sample_app.run()
您将创建一个 global 变量来保存图片的文件名，然后在您的 screenfour Screen 中创建一个 Image 小部件，您将在其中将图像小部件的源更新为您拍摄的照片的文件名。有问题随时联系我
访问照片
使用以下方式引用照片：
class ScreenFour(Screen):
def on_pre_enter(self, *args):
self.ids.img.source = self.manager.ids.entry.photo
解决方案
备注
<class-name@widget>:
这是一个dynamic class。使用动态 class 时，不需要在 Python 脚本中定义 class。
kv 文件
- 通过删除所有
@Screen. 将所有动态 classes 更改为 class 规则
- 添加一个class规则，
<ScreenManagement>:
- 将所有屏幕实例化为 class 规则的子项，
<ScreenManagement>:
- 在实例化子项下添加
id: entry，ScreenThree:
- 实例化，
Image: 作为 class 规则的 FloatLayout: 的子项，<ScreenFour>:
- 在实例化子项下添加
id: img，Image:
片段
#:import MDIconButton kivymd.button.MDIconButton
<ScreenManagement>:
ScreenOne:
name: "screen_one"
ScreenTwo:
name: "screen_two"
ScreenThree:
id: entry
name: "screen_three"
ScreenFour:
name: "screen_four"
...
<ScreenFour>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
Image:
id: img
Py文件
- 添加导入语句，
from os.path import dirname
- 添加导入语句，
from kivy.properties import StringProperty
- 添加
class ScreenManagement()
- 删除对
screen_manager 的所有引用
- 在
class ScreenThree() 下声明class属性，photo = StringProperty('')
- 初始化class属性，
self.photo = f"{dirname(__file__)}/IMG_{time.strftime('%Y%m%d_%H%M%S')}.png"
- 实现方法
on_pre_enter() 以显示照片。
片段
from os.path import dirname
from kivy.properties import StringProperty
...
class ScreenThree(Screen):
photo = StringProperty('')
def capture(self):
camera = self.ids['camera']
self.photo = f"{dirname(__file__)}/IMG_{time.strftime('%Y%m%d_%H%M%S')}.png"
camera.export_to_png(self.photo)
print("Captured")
class ScreenFour(Screen):
def on_pre_enter(self, *args):
self.ids.img.source = self.manager.ids.entry.photo
class ScreenManagement(ScreenManager):
pass
class Interface(App):
def build(self):
return ScreenManagement()
例子
main.py
from os.path import dirname
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
from kivymd.theming import ThemeManager
from kivy.properties import StringProperty
import time
Builder.load_string("""
#:import MDFillRoundFlatButton kivymd.button.MDFillRoundFlatButton
#:import MDIconButton kivymd.button.MDIconButton
<ScreenManagement>:
ScreenOne:
name: "screen_one"
ScreenTwo:
name: "screen_two"
ScreenThree:
name: "screen_three"
id: entry
ScreenFour:
name: "screen_four"
<ScreenOne>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
MDFillRoundFlatButton:
color: [1,1,1,1]
text: "Перейти к созданию фото"
pos_hint: {'center_x':.50, 'center_y':.50}
on_press:
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_two'
<ScreenTwo>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
MDFillRoundFlatButton:
color: [1,1,1,1]
text: "Выбрать фон"
pos_hint: {'center_x':.50, 'center_y':.10}
on_press:
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_three'
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_one'
<ScreenThree>:
id: entry
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
Camera:
id: camera
index: 0
resolution: (1280,720)
play: True
MDFillRoundFlatButton:
text: "take photo"
pos_hint: {'center_x': 0.50, 'center_y': .10}
on_press:
root.capture() #TAKE PHOTO
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_four'
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_two'
<ScreenFour>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
Image:
id: img
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_three'
""")
class ScreenOne(Screen):
pass
class ScreenTwo(Screen):
theme_cls = ThemeManager()
theme_cls.primary_palette = 'Blue'
main_widget = None
class ScreenThree(Screen):
theme_cls = ThemeManager()
theme_cls.primary_palette = 'Blue'
main_widget = None
photo = StringProperty('')
def capture(self):
camera = self.ids['camera']
self.photo = f"{dirname(__file__)}/IMG_{time.strftime('%Y%m%d_%H%M%S')}.png"
camera.export_to_png(self.photo)
print("Captured")
class ScreenFour(Screen):
def on_pre_enter(self, *args):
self.ids.img.source = self.manager.ids.entry.photo
class ScreenManagement(ScreenManager):
pass
class Interface(App):
def build(self):
return ScreenManagement()
sample_app = Interface()
sample_app.run()
输出
下午好，我使用 Python 和 Kivy 编写了一个简单的相机程序，但我就是拍不到照片。您需要拍摄 "ScreenThree" 的快照（将其保存在 phone 的内存中）并将生成的图像显示在 "ScreenFour" 上。
我用kivy.uix.camera显示摄像头，kivymd和kv创建界面。 android.permissions：互联网，相机，WRITE_EXTERNAL_STORAGE，READ_EXTERNAL_STORAGE
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.uix.camera import Camera
from kivymd.theming import ThemeManager
import time
Builder.load_string("""
#:import MDFillRoundFlatButton kivymd.button.MDFillRoundFlatButton
#:import MDIconButton kivymd.button.MDIconButton
<ScreenOne@Screen>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
MDFillRoundFlatButton:
color: [1,1,1,1]
text: "Перейти к созданию фото"
pos_hint: {'center_x':.50, 'center_y':.50}
on_press:
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_two'
<ScreenTwo@Screen>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
MDFillRoundFlatButton:
color: [1,1,1,1]
text: "Выбрать фон"
pos_hint: {'center_x':.50, 'center_y':.10}
on_press:
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_three'
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_one'
<ScreenThree@Screen>:
id: entry
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
Camera:
id: camera
index: 0
resolution: (1280,720)
play: True
MDFillRoundFlatButton:
text: "take photo"
pos_hint: {'center_x': 0.50, 'center_y': .10}
on_press:
root.capture() #TAKE PHOTO
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_four'
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_two'
<ScreenFour@Screen>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
# HERE I NEED TO DISPLAY THE IMAGE
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_three'
""")
class ScreenOne(Screen):
pass
class ScreenTwo(Screen):
theme_cls = ThemeManager()
theme_cls.primary_palette = 'Blue'
main_widget = None
class ScreenThree(Screen):
theme_cls = ThemeManager()
theme_cls.primary_palette = 'Blue'
main_widget = None
def capture(self):
camera = self.ids['camera']
timestr = time.strftime("%Y%m%d_%H%M%S")
photo = camera.export_to_png("IMG_{}.png".format(timestr))
print("Captured")
class ScreenFour(Screen):
pass
screen_manager = ScreenManager()
screen_manager.add_widget(ScreenOne(name="screen_one"))
screen_manager.add_widget(ScreenTwo(name="screen_two"))
screen_manager.add_widget(ScreenThree(name="screen_three"))
screen_manager.add_widget(ScreenFour(name="screen_four"))
class Interface(App):
def build(self):
return screen_manager
sample_app = Interface()
sample_app.run()
请告诉我，我该如何修改代码才能完成任务。
错误
Take photo White screen
04-08 21:15:19.925 796 13801 E mm-camera: <STATS_AF ><ERROR> 959: af_spd_detect_process: ERROR! SPOT_LIGHT_FLAG =0!!! :AEC_grid = 256, BG_grid = 3072, ave luma = 0
04-08 21:15:19.933 835 902 W SurfaceFlinger: EventThread: dropping event (7673796e) for connection 0x7b332278c0
04-08 21:15:19.949 835 902 W SurfaceFlinger: EventThread: dropping event (7673796e) for connection 0x7b332278c0
04-08 21:15:19.959 796 13801 E mm-camera: <STATS_AF ><ERROR> 959: af_spd_detect_process: ERROR! SPOT_LIGHT_FLAG =0!!! :AEC_grid = 256, BG_grid = 3072, ave luma = 0
04-08 21:15:19.966 835 902 W SurfaceFlinger: EventThread: dropping event (7673796e) for connection 0x7b332278c0
04-08 21:15:19.983 835 902 W SurfaceFlinger: EventThread: dropping event (7673796e) for connection 0x7b332278c0
04-08 21:15:19.992 796 13801 E mm-camera: <STATS_AF ><ERROR> 959: af_spd_detect_process: ERROR! SPOT_LIGHT_FLAG =0!!! :AEC_grid = 256, BG_grid = 3072, ave luma = 0
04-08 21:15:19.999 835 902 W SurfaceFlinger: EventThread: dropping event (7673796e) for connection 0x7b332278c0
错误2
04-09 08:27:25.140 796 6243 E mm-camera: <STATS_AF ><ERROR> 959: af_spd_detect_process: ERROR! SPOT_LIGHT_FLAG =0!!! :AEC_grid = 256, BG_grid = 3072, ave luma = 0
04-09 08:27:25.146 835 902 W SurfaceFlinger: EventThread: dropping event (7673796e) for connection 0x7b32a54420
04-09 08:27:25.146 6164 6198 I python : Captured
04-09 08:27:25.147 6164 6198 I python : [ERROR ] [Image ] Error reading file IMG_20190409_082724.png
04-09 08:27:25.162 835 902 W SurfaceFlinger: EventThread: dropping event (7673796e) for connection 0x7b32a54420
04-09 08:27:25.175 796 6243 E mm-camera: <STATS_AF ><ERROR> 959: af_spd_detect_process: ERROR! SPOT_LIGHT_FLAG =0!!! :AEC_grid = 256, BG_grid = 3072, ave luma = 0
04-09 08:27:25.179 835 902 W SurfaceFlinger: EventThread: dropping event (7673796e) for connection 0x7b32a54420
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.uix.camera import Camera
from kivymd.theming import ThemeManager
import time
filename = ''
screenfour = ''
Builder.load_string("""
#:import MDFillRoundFlatButton kivymd.button.MDFillRoundFlatButton
#:import MDIconButton kivymd.button.MDIconButton
<ScreenOne@Screen>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
MDFillRoundFlatButton:
color: [1,1,1,1]
text: "Перейти к созданию фото"
pos_hint: {'center_x':.50, 'center_y':.50}
on_press:
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_two'
<ScreenTwo@Screen>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
MDFillRoundFlatButton:
color: [1,1,1,1]
text: "Выбрать фон"
pos_hint: {'center_x':.50, 'center_y':.10}
on_press:
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_three'
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_one'
<ScreenThree@Screen>:
id: entry
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
Camera:
id: camera
index: 0
resolution: (1280,720)
play: True
MDFillRoundFlatButton:
text: "take photo"
pos_hint: {'center_x': 0.50, 'center_y': .10}
on_press:
root.capture() #TAKE PHOTO
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_four'
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_two'
<ScreenFour@Screen>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
Image:
size: root.width, root.height
source: ''
id: imageWid
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_three'
""")
class ScreenOne(Screen):
pass
class ScreenTwo(Screen):
theme_cls = ThemeManager()
theme_cls.primary_palette = 'Blue'
main_widget = None
class ScreenThree(Screen):
theme_cls = ThemeManager()
theme_cls.primary_palette = 'Blue'
main_widget = None
def capture(self):
camera = self.ids['camera']
timestr = time.strftime("%Y%m%d_%H%M%S")
photo = camera.export_to_png("IMG_{}.png".format(timestr))
global filename, screenfour
filename = "IMG_{}.png".format(timestr)
print("Captured")
screenfour.update()
class ScreenFour(Screen):
def __init__(self, **kwargs):
super(ScreenFour, self).__init__(**kwargs)
global screenfour
screenfour = self
def update(self, *args):
global filename
imageWidget = self.ids['imageWid']
imageWidget.source = filename
screen_manager = ScreenManager()
screen_manager.add_widget(ScreenOne(name="screen_one"))
screen_manager.add_widget(ScreenTwo(name="screen_two"))
screen_manager.add_widget(ScreenThree(name="screen_three"))
screen_manager.add_widget(ScreenFour(name="screen_four"))
class Interface(App):
def build(self):
return screen_manager
sample_app = Interface()
sample_app.run()
您将创建一个 global 变量来保存图片的文件名，然后在您的 screenfour Screen 中创建一个 Image 小部件，您将在其中将图像小部件的源更新为您拍摄的照片的文件名。有问题随时联系我
访问照片
使用以下方式引用照片：
class ScreenFour(Screen):
def on_pre_enter(self, *args):
self.ids.img.source = self.manager.ids.entry.photo
解决方案
备注
<class-name@widget>:
这是一个dynamic class。使用动态 class 时，不需要在 Python 脚本中定义 class。
kv 文件
- 通过删除所有
@Screen. 将所有动态 classes 更改为 class 规则
- 添加一个class规则，
<ScreenManagement>: - 将所有屏幕实例化为 class 规则的子项，
<ScreenManagement>: - 在实例化子项下添加
id: entry，ScreenThree: - 实例化，
Image:作为 class 规则的FloatLayout:的子项，<ScreenFour>: - 在实例化子项下添加
id: img，Image:
片段
#:import MDIconButton kivymd.button.MDIconButton
<ScreenManagement>:
ScreenOne:
name: "screen_one"
ScreenTwo:
name: "screen_two"
ScreenThree:
id: entry
name: "screen_three"
ScreenFour:
name: "screen_four"
...
<ScreenFour>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
Image:
id: img
Py文件
- 添加导入语句，
from os.path import dirname - 添加导入语句，
from kivy.properties import StringProperty - 添加
class ScreenManagement() - 删除对
screen_manager 的所有引用
- 在
class ScreenThree()下声明class属性， - 初始化class属性，
self.photo = f"{dirname(__file__)}/IMG_{time.strftime('%Y%m%d_%H%M%S')}.png" - 实现方法
on_pre_enter()以显示照片。
photo = StringProperty('')
片段
from os.path import dirname
from kivy.properties import StringProperty
...
class ScreenThree(Screen):
photo = StringProperty('')
def capture(self):
camera = self.ids['camera']
self.photo = f"{dirname(__file__)}/IMG_{time.strftime('%Y%m%d_%H%M%S')}.png"
camera.export_to_png(self.photo)
print("Captured")
class ScreenFour(Screen):
def on_pre_enter(self, *args):
self.ids.img.source = self.manager.ids.entry.photo
class ScreenManagement(ScreenManager):
pass
class Interface(App):
def build(self):
return ScreenManagement()
例子
main.py
from os.path import dirname
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
from kivymd.theming import ThemeManager
from kivy.properties import StringProperty
import time
Builder.load_string("""
#:import MDFillRoundFlatButton kivymd.button.MDFillRoundFlatButton
#:import MDIconButton kivymd.button.MDIconButton
<ScreenManagement>:
ScreenOne:
name: "screen_one"
ScreenTwo:
name: "screen_two"
ScreenThree:
name: "screen_three"
id: entry
ScreenFour:
name: "screen_four"
<ScreenOne>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
MDFillRoundFlatButton:
color: [1,1,1,1]
text: "Перейти к созданию фото"
pos_hint: {'center_x':.50, 'center_y':.50}
on_press:
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_two'
<ScreenTwo>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
MDFillRoundFlatButton:
color: [1,1,1,1]
text: "Выбрать фон"
pos_hint: {'center_x':.50, 'center_y':.10}
on_press:
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_three'
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_one'
<ScreenThree>:
id: entry
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
Camera:
id: camera
index: 0
resolution: (1280,720)
play: True
MDFillRoundFlatButton:
text: "take photo"
pos_hint: {'center_x': 0.50, 'center_y': .10}
on_press:
root.capture() #TAKE PHOTO
root.manager.transition.direction = 'up'
root.manager.transition.duration = 1
root.manager.current = 'screen_four'
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_two'
<ScreenFour>:
canvas:
Color:
rgb: [.30,.50,.99]
Rectangle:
pos: self.pos
size: self.size
FloatLayout:
Image:
id: img
MDIconButton:
icon: 'chevron-double-right'
pos_hint: {'center_x':.95, 'center_y':.10}
on_press:
root.manager.transition.direction = 'down'
root.manager.transition.duration = 1
root.manager.current = 'screen_three'
""")
class ScreenOne(Screen):
pass
class ScreenTwo(Screen):
theme_cls = ThemeManager()
theme_cls.primary_palette = 'Blue'
main_widget = None
class ScreenThree(Screen):
theme_cls = ThemeManager()
theme_cls.primary_palette = 'Blue'
main_widget = None
photo = StringProperty('')
def capture(self):
camera = self.ids['camera']
self.photo = f"{dirname(__file__)}/IMG_{time.strftime('%Y%m%d_%H%M%S')}.png"
camera.export_to_png(self.photo)
print("Captured")
class ScreenFour(Screen):
def on_pre_enter(self, *args):
self.ids.img.source = self.manager.ids.entry.photo
class ScreenManagement(ScreenManager):
pass
class Interface(App):
def build(self):
return ScreenManagement()
sample_app = Interface()
sample_app.run()