拖放图像并在网格布局上显示图像 - Kivy

Question

我是 kivy 的新手，我正在尝试创建一个拖放应用程序，如果将图像拖放到网格布局上，则图像将显示在应用程序上，如下所示。我试图获取图像的文件路径，然后使用文件路径将其显示在网格布局上，但不幸的是，这不起作用。任何帮助将不胜感激！

这是当前图像

这就是我拖动图片后想要的效果

Kv文件

# Custom button
<CustButton@Button>:
    font_size: 32
    background_normal: 'Colour_yellow.png'
    background_down: 'Colour_blue.png'

<Cust2@Button>:
    font_size: 32
    background_normal: 'Colour_red.png'
    background_down: 'Colour_blue.png'

<Cust3@Button>:
    font_size: 32
    background_normal: 'Colour_white.png'
    background_down: 'Colour_blue.png'

<Cust4@Button>:
    font_size: 32
    background_normal: 'Colour_blue.png'
    background_down: 'Colour_white.png'

<CalcGridLayout>:
    id: calculator
    display: entry
    rows: 5
    padding: 10
    spacing: 10

    BoxLayout:
        spacing: 100
        size_hint: .5, None
        Cust2:
            text: "Whats the intensity you want?"

    BoxLayout:

        size_hint: .5, None
        TextInput:
            id: entry
            font_size: 70
            multiline: False
            hint_text: "Type here"

    BoxLayout:
        spacing: 100
        size_hint: .5, None
        Cust4:
            text: "Drag and Drop picture below:"
            on_release: root.build1()

    #THIS IS WHERE I'M STUCK ON
    BoxLayout:
        Image:
            source: root._on_file_drop(file_path)

    BoxLayout:
        size_hint: 1, .3
        spacing: 10

        CustButton:
            text: "Click here for \n reduced size"

        CustButton:
            text: "Click here for pos \n  and intensity of \n      each pixel"
            on_release: root.reduced_image()

        CustButton:
            text: "Click here \n for graph"

        CustButton:
            text: "Click here \n     for all"

        CustButton:
            text: "Extra"

Python文件

import kivy

kivy.require("1.9.0")

from kivy.app import App
from kivy.uix.gridlayout import GridLayout
from kivy.core.window import Window
Window.clearcolor = (0.5, 0.5, 0.5, 1)


class CalcGridLayout(GridLayout):

    def reduced_image(self):
    #ignore

    def build1(self):
        Window.bind(on_dropfile=self._on_file_drop)
        return

    def _on_file_drop(self, window, file_path):
        print(file_path)
        return file_path



class dropdownApp(App):

    def build(self):
        return CalcGridLayout()


dropApp = dropdownApp()
dropApp.run()

Answer 1

解决方案

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请参阅片段和完整示例以了解详细信息。

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kv文件

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1. 消除on_release: root.build1()
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2. 代替source: root._on_file_drop(file_path)用。。。来id: img
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片段

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BoxLayout:\n    spacing: 100\n    size_hint: .5, None\n    Cust4:\n        text: "Drag and Drop picture below:"\n\nBoxLayout:\n    Image:\n        id: img\n

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Python代码

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1. 添加导入语句，from kivy.properties import StringProperty
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2. 申报财产，filePath = StringProperty(\'\')在class CalcGridLayout().
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3. 将构造函数添加到方法并从方法中class CalcGridLayout()移动Window.bind(on_dropfile=self._on_file_drop)build1()
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4. 去除build1()方法
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5. 在_on_file_drop()方法中，替换return file_path为self.filePath = file_path.decode("utf-8") self.ids.img.source = self.filePathandself.ids.img.reload()
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片段

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from kivy.properties import StringProperty\n...\n\nclass CalcGridLayout(GridLayout):\n    filePath = StringProperty(\'\')\n\n    def __init__(self, **kwargs):\n        super(CalcGridLayout, self).__init__(**kwargs)\n        Window.bind(on_dropfile=self._on_file_drop)\n\n    def reduced_image(self):\n        print(self.filePath)\n\n    def _on_file_drop(self, window, file_path):\n        print(file_path)\n        self.filePath = file_path.decode("utf-8")     # convert byte to string\n        self.ids.img.source = self.filePath\n        self.ids.img.reload()   # reload image\n

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窗口 \xc2\xbb on_dropfile 事件

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on_dropfile(filename)\n

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将文件拖放到应用程序上时调用的事件。

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警告

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此事件当前适用于 sdl2 窗口提供程序、pygame 窗口\n 提供程序和带有 pygame 修补版本的 OS X。此事件保留\n以供进一步发展（ios、android 等）

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例子

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主要.py

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import kivy\nkivy.require("1.11.0")\n\nfrom kivy.app import App\nfrom kivy.uix.gridlayout import GridLayout\nfrom kivy.core.window import Window\nfrom kivy.properties import StringProperty\n\nWindow.clearcolor = (0.5, 0.5, 0.5, 1)\n\n\nclass CalcGridLayout(GridLayout):\n    filePath = StringProperty(\'\')\n\n    def __init__(self, **kwargs):\n        super(CalcGridLayout, self).__init__(**kwargs)\n        Window.bind(on_dropfile=self._on_file_drop)\n\n    def reduced_image(self):\n        print(self.filePath)\n\n    def _on_file_drop(self, window, file_path):\n        print(file_path)\n        self.filePath = file_path.decode("utf-8")     # convert byte to string\n        self.ids.img.source = self.filePath\n        self.ids.img.reload()   # reload image\n\n\nclass DragDropApp(App):\n\n    def build(self):\n        return CalcGridLayout()\n\n\nif __name__ == "__main__":\n    DragDropApp().run()\n

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拖放.kv

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#:kivy 1.11.0\n\n# Custom button\n<CustButton@Button>:\n    background_normal: "/home/iam/Pictures/AppImages/Colors/yellow.png"   # \'Colour_yellow.png\'\n    background_down: "/home/iam/Pictures/AppImages/Colors/blue.png"       # \'Colour_blue.png\'\n    text_size: self.size\n    halign: \'center\'\n    valign: \'middle\'\n\n<Cust2@Button>:\n    font_size: 32\n    background_normal: "/home/iam/Pictures/AppImages/Colors/red.png"   # \'Colour_red.png\'\n    background_down: "/home/iam/Pictures/AppImages/Colors/blue.png"     # \'Colour_blue.png\'\n\n<Cust3@Button>:\n    font_size: 32\n    background_normal: "/home/iam/Pictures/AppImages/Colors/white.png"     # \'Colour_white.png\'\n    background_down: "/home/iam/Pictures/AppImages/Colors/blue.png"       # \'Colour_blue.png\'\n\n<Cust4@Button>:\n    font_size: 32\n    background_normal: "/home/iam/Pictures/AppImages/Colors/blue.png"     # \'Colour_blue.png\'\n    background_down: "/home/iam/Pictures/AppImages/Colors/white.png"       # \'Colour_white.png\'\n\n<CalcGridLayout>:\n    id: calculator\n    display: entry\n    rows: 5\n    padding: 10\n    spacing: 10\n\n    BoxLayout:\n        spacing: 100\n        size_hint: .5, None\n        Cust2:\n            text: "Whats the intensity you want?"\n\n    BoxLayout:\n        size_hint: .5, None\n        TextInput:\n            id: entry\n            font_size: 70\n            multiline: False\n            hint_text: "Type here"\n\n    BoxLayout:\n        spacing: 100\n        size_hint: .5, None\n        Cust4:\n            text: "Drag and Drop picture below:"\n\n    BoxLayout:\n        Image:\n            id: img\n\n    BoxLayout:\n        size_hint: 1, .3\n        spacing: 10\n\n        CustButton:\n            text: "Click here for \\n reduced size"\n\n        CustButton:\n            text: "Click here for pos \\n  and intensity of \\n      each pixel"\n            on_release: root.reduced_image()\n\n        CustButton:\n            text: "Click here \\n for graph"\n\n        CustButton:\n            text: "Click here \\n     for all"\n\n        CustButton:\n            text: "Extra"\n

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输出

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