上周我一直在使用 Kivy 和 KivyMD 进行编程，我尝试开发一个具有图像选择器的应用程序。我遇到的问题是，无论我使用什么，它都不会显示我手机的媒体，也不会请求访问权限。
我使用 FileChooserIconView 创建一个显示手机文件的新屏幕。我在 MDApp 的 on_start 中尝试使用此代码：
if platform == 'android':
from android.permissions import request_permissions, Permission
request_permissions([Permission.READ_EXTERNAL_STORAGE, Permission.READ_MEDIA_IMAGES])
但它一直只显示文件夹而不显示文件。 我希望它显示所有内容，目前它只显示文件夹。
这是main.py：
from kivy.uix.screenmanager import ScreenManager
from kivymd.app import MDApp
from kivymd.uix.screen import MDScreen
from kivymd.uix.label import MDLabel
from kivy.uix.image import Image
from kivy.uix.gridlayout import GridLayout
from kivy import platform
import json
import os
import unicodedata
class MainScreen(MDScreen):
def normalizar_texto(self, texto):
# Normaliza el texto: elimina tildes y convierte a minúsculas
texto_sin_tildes = unicodedata.normalize('NFKD', texto).encode('ASCII', 'ignore').decode('utf-8')
return texto_sin_tildes.lower().strip()
def load_beasts(self):
# Load characters from a JSON file and add them to the screen
if os.path.exists('beasts.json'):
with open('beasts.json', 'r') as f:
beasts = json.load(f)
return beasts
else:
return [{"id": 0, "name": "Error", "image": "", "description": "No existe archivo"}]
def on_search_button(self):
# Get the text from TextInput when the button is pressed
search_text = self.ids.search_input.text
dex = self.load_beasts()
if search_text.strip().isdigit():
result = [beast for beast in dex if beast['id'] == int(search_text)]
elif self.normalizar_texto(search_text) == 'abel':
result = [{"id": "???", "image": "images/abel.jpeg","name": "Abel Cid Outlaw",
"description": "La criatura más cruel y despiadada de todo el multiverso. No teme a nada, no aprecia a nadie. Solo desea ver como el mundo arde bajo sus pies."}]
else:
result = [beast for beast in dex if self.normalizar_texto(beast['name']) == self.normalizar_texto(search_text)]
if result:
self.mostrar_informacion(result[0])
def mostrar_informacion(self, beast):
# Asumimos que hay etiquetas para mostrar los datos en la interfaz
self.ids.name_label.text = f"{beast['id']}. {beast['name']}"
self.ids.beast_img.source = beast['image']
self.ids.beast_img.height = 500
#self.ids.beast_img.reload()
self.ids.descrip_label.text= f"Descripción: {beast['description']}"
def load_beasts_db(self):
db_screen = self.manager.get_screen('db')
beasts = self.load_beasts()
for beast in beasts:
db_screen.add_beast_widget(beast)
class DBScreen(MDScreen):
def add_beast_widget(self, beast_data):
main_screen = self.manager.get_screen('main')
label = MDLabel(
text= f"{beast_data['id']}.{beast_data['name']}",
font_style="H5",
halign="center",
theme_text_color="Custom",
text_color= (0, 0, 0, 1)
)
img = Image(
source=beast_data['image'],
size=(200,200),
allow_stretch=True,
keep_ratio=False,
size_hint_y=None,
height=200
)
grid=GridLayout(
cols= 1,
spacing= 30,
padding= 20,
size_hint_y=None,
height=250
)
grid.add_widget(img)
grid.add_widget(label)
main_screen.ids.beast_list.add_widget(grid)
class AddScreen(MDScreen):
def open_file_chooser(self):
# Cambia a la pantalla de FileChooser
main_screen = self.manager.get_screen('main')
main_screen.ids.beast_name.text = main_screen.ids.beast_name.text
main_screen.ids.beast_description.text = main_screen.ids.beast_description.text
self.manager.current = "file_chooser"
def save_beast(self):
db_screen = self.manager.get_screen('db')
main_screen = self.manager.get_screen('main')
id = len(main_screen.load_beasts()) + 1
name = main_screen.ids.beast_name.text
image = main_screen.ids.image_display.source
description = main_screen.ids.beast_description.text
beast_data = {
'id': id,
'name': name,
'image': image,
'description': description
}
# Save character to the list
self.save_beasts_to_file(beast_data)
# Add button to the main screen dynamically
db_screen.add_beast_widget(beast_data)
# Clear the inputs after saving
main_screen.ids.beast_name.text = ''
main_screen.ids.image_display.source = ''
main_screen.ids.beast_description.text = ''
# Switch back to the main screen
self.manager.current = 'main'
def save_beasts_to_file(self, new_beast):
beasts = []
# Load existing characters from file if it exists
if os.path.exists('beasts.json'):
with open('beasts.json', 'r') as f:
beasts = json.load(f)
# Add the new character
beasts.append(new_beast)
# Save updated character list to file
with open('beasts.json', 'w') as f:
json.dump(beasts, f)
class FileChooserScreen(MDScreen):
def select_image(self, selection):
# Verifica si hay un archivo seleccionado
if selection:
main_screen = self.manager.get_screen("main")
main_screen.ids.image_display.source = selection[0]
self.manager.current = "main"
class BeastDexApp(MDApp):
def on_start(self):
# Llama a load_beasts_db solo al iniciar la aplicación
main_screen = self.root.get_screen('main')
main_screen.load_beasts_db()
if platform == 'android':
from android.permissions import request_permissions, Permission
request_permissions([Permission.READ_EXTERNAL_STORAGE, Permission.READ_MEDIA_IMAGES])
def build(self):
sm = ScreenManager()
sm.add_widget(MainScreen(name='main'))
sm.add_widget(DBScreen(name='db'))
sm.add_widget(AddScreen(name='add'))
sm.add_widget(FileChooserScreen(name='file_chooser'))
return sm
if __name__ == '__main__':
BeastDexApp().run()
这是.kv 文件：
#:import platform kivy.utils.platform
<MainScreen>:
canvas.before:
Color:
rgba: 1, 1, 1, 1
Rectangle:
size: self.size
pos: self.pos
source: 'img.jpg'
MDNavigationLayout:
MDScreenManager:
id: screen_manager
MDScreen:
# Main background image
name: 'main'
FloatLayout:
# Menu icon
MDIconButton:
icon: "menu"
pos_hint: {"center_x": 0.05, "center_y": 0.95}
on_release: nav_drawer.set_state("toggle")
MDLabel:
text: 'BeastDex'
theme_text_color: "Custom"
text_color: 1, 1, 1, 1
font_style: "H1"
pos_hint: {'top': 0.95, 'center_x': 0.5}
halign: "center"
font_name: 'Amores Free Font.ttf'
size_hint_y: None
height: dp(60)
# Main content layout
BoxLayout:
orientation: 'vertical'
padding: [20, 200, 20, 20]
spacing: dp(20)
size_hint_y: 1
# Search bar layout
BoxLayout:
orientation: 'horizontal'
padding: dp(10)
spacing: dp(10)
size_hint_y: None
height: dp(50)
MDTextField:
id: search_input
hint_text: "Buscar bestia"
size_hint_x: 0.8
height: dp(50)
multiline: False
MDRaisedButton:
text: "Search"
size_hint_x: 0.2
height: dp(50)
on_release: root.on_search_button()
# Data layout for result display
ScrollView:
do_scroll_x: False
GridLayout:
cols: 1
spacing: dp(30)
padding: dp(20)
size_hint_y: None
height: self.minimum_height
# Display name label
MDLabel:
id: name_label
text: ""
font_style: "H5"
halign: "center"
theme_text_color: "Custom"
text_color: 0, 0, 0, 1
# Beast image display
Image:
id: beast_img
source: ''
size_hint_y: None
height: 0
allow_stretch: True
keep_ratio: True
# Description label
MDLabel:
id: descrip_label
text: ""
font_style: "Body1"
halign: "center"
theme_text_color: "Custom"
text_color: 0, 0, 0, 1
MDScreen:
name: 'db'
BoxLayout:
orientation: 'vertical'
MDIconButton:
icon: "menu"
pos_hint: {"center_x": 0.05, "center_y": 0.95}
on_release: nav_drawer.set_state("toggle")
MDLabel:
text: 'BeastDex'
theme_text_color: "Custom"
text_color: 1, 1, 1, 1
font_style: "H1"
pos_hint: {'top': 0.95, 'center_x': 0.5}
halign: "center"
font_name: 'Amores Free Font.ttf'
size_hint_y: None
height: dp(60)
ScrollView:
do_scroll_x: False # Disable horizontal scrolling if not needed
GridLayout:
id: beast_list
cols: 2
spacing: dp(10)
padding: [dp(40), ]
size_hint_y: None
height: self.minimum_height
MDScreen:
name: 'add'
BoxLayout:
orientation: 'vertical'
MDIconButton:
icon: "menu"
pos_hint: {"center_x": 0.05, "center_y": 0.95}
on_release: nav_drawer.set_state("toggle")
MDLabel:
text: 'BeastDex'
theme_text_color: "Custom"
text_color: 1, 1, 1, 1
font_style: "H1"
pos_hint: {'top': 0.95, 'center_x': 0.5}
halign: "center"
font_name: 'Amores Free Font.ttf'
size_hint_y: None
height: dp(60)
ScrollView:
size_hint: 1, 0.85 # Make it take up the remaining space
pos_hint: {'top': 0.85}
do_scroll_x: False # Disable horizontal scrolling
BoxLayout:
orientation: 'vertical'
size_hint_y: None
height: self.minimum_height
padding: [20, 20, 20, 20] # Add some padding for spacing
spacing: 20 # Add some space between elements
Label:
text: 'Nombre'
color: 0, 0, 0, 1
halign: "center"
TextInput:
id: beast_name
hint_text: ""
multiline: False
size_hint_y: None
height: 60
Label:
text: 'Imagen'
color: 0, 0, 0, 1
halign: "center"
MDRaisedButton:
text: "Seleccionar Imagen"
pos_hint: {"center_x": 0.5}
on_release: app.root.get_screen('add').open_file_chooser()
Image:
id: image_display
source: ""
size_hint_y: None
height: 50
allow_stretch: True
keep_ratio: True
Label:
text: 'Descripción'
color: 0, 0, 0, 1
halign: "center"
TextInput:
id: beast_description
hint_text: ""
multiline: False
size_hint_y: None
height: 60
Button:
text: "Save Beast"
size_hint_y: None
height: 70
on_release: app.root.get_screen('add').save_beast()
MDNavigationDrawer:
id: nav_drawer
BoxLayout:
orientation: 'vertical'
size_hint_y: None
spacing: 10
height: self.minimum_height # Asegura que el tamaño se ajuste al contenido
pos_hint: {'top': 1}
MDLabel:
text: "Enciclopedia:\n Las Bestias del Multiverso"
theme_text_color: 'Custom'
text_color: 0, 0, 0, 1
halign: 'center'
font_style: 'H6'
size_hint_y: None
height: self.texture_size[1]
# Línea separadora
Widget:
size_hint_y: None
height: dp(3) # Altura de la línea separadora
canvas:
Color:
rgba: 0.7, 0.7, 0.7, 1 # Color de la línea
Rectangle:
size: self.size
pos: self.pos
MDList:
OneLineIconListItem:
text: "Buscador"
theme_text_color: 'Custom'
text_color: 0, 0, 0, 1.0
on_release:
nav_drawer.set_state("close")
screen_manager.current = 'main'
OneLineIconListItem:
text: "Todas las Bestias"
theme_text_color: 'Custom'
text_color: 0, 0, 0, 1.0
on_release:
nav_drawer.set_state("close")
screen_manager.current = 'db'
OneLineIconListItem:
text: "Añadir Bestia"
theme_text_color: 'Custom'
text_color: 0, 0, 0, 1.0
on_release:
nav_drawer.set_state("close")
screen_manager.current = 'add'
<FileChooserScreen>:
BoxLayout:
orientation: 'vertical'
canvas.before:
Color:
rgba: 0.5, 0.5, 0.5, 1 # Color de fondo (modifícalo a tu gusto)
Rectangle:
pos: self.pos
size: self.size
FileChooserIconView:
rootpath: '/storage/emulated/0/' if platform == 'android' else '/'
id: filechooser
on_selection: root.select_image(filechooser.selection)
根据 python-for-android 文档。
如果你想存储和检索数据，你不应该只保存到 当前目录，而不是硬编码 /sdcard/ 或其他路径
- 每个设备可能会有所不同。
相反，您可以将 Android 模块添加到您的需求中 允许您查询最常用的路径：
从 android.storage 导入 app_storage_path 设置_path = 应用程序_存储_路径（）
从 android.storage 导入primary_external_storage_path Primary_ext_storage = Primary_external_storage_path()
从 android.storage 导入 secondary_external_storage_path secondary_ext_storage = secondary_external_storage_path()
代替：
FileChooserIconView:
rootpath: '/storage/emulated/0/' if platform == 'android' else '/'
id: filechooser
on_selection: root.select_image(filechooser.selection)
尝试：
FileChooserIconView:
rootpath: app.path() # App class
id: filechooser
on_selection: root.select_image(filechooser.selection)
由于您从 Android 文件获取图像：
def path(self):
from android.storage import primary_external_storage_path
ext_storage = primary_external_storage_path()
pictures_path = os.path.join(ext_storage, 'DCIM', 'Images') # Put your image path here
此外，使用 Permission.WRITE_EXTERNAL_STORAGE 时没有显示权限请求的原因是因为根据 android 文档：
如果您的应用程序位于运行 API 级别 19 或更高级别的设备上，则无需声明此权限即可在 Context.getExternalFilesDir(String) 和 Context.getExternalCacheDir() 返回的应用程序特定目录中读取和写入文件.