Question

我想在Kivy文本输入中居中一行文本。我将使用填充

$('option').filter(function(){
    return !$('#' + this.value).length;
}).remove()// or prop('disabled', true);

但是我无法找到线条的宽度。如何计算或访问线宽？

Answer 1

您可以使用内部TextInput._get_text_width方法来计算正确的填充：

from kivy.app import App
from kivy.uix.floatlayout import FloatLayout
from kivy.lang import Builder

Builder.load_string('''

<MyWidget>:
    TextInput:
        multiline: False
        on_text: root.update_padding(args[0])
        padding_x: self.width/2 # initial padding
''')

class MyWidget(FloatLayout):
    def update_padding(self, text_input, *args):
        text_width = text_input._get_text_width(
            text_input.text,
            text_input.tab_width,
            text_input._label_cached
        )
        text_input.padding_x = (text_input.width - text_width)/2

class MyApp(App):
    def build(self):        
        return MyWidget()

if __name__ == '__main__':
    MyApp().run()

Answer 2

上面的解决方案几乎对我有用。有时填充不会正确更新。这是我的微小更改，将text_width设置为NumericProperty：

在Kivy：

<CenteredTextInput@TextInput>:
    multiline: False
    on_text: root.update_padding()
    padding_x: (self.width - self.text_width) / 2

在Python中：

class CenteredTextInput(TextInput):
    '''
    A centered TextInput.
    '''

    text_width = NumericProperty()
    '''The text width
    '''

    def update_padding(self, *args):
        '''
        Update the padding so the text is centered
        '''
        self.text_width = self._get_text_width(
            self.text,
            self.tab_width,
            self._label_cached
        )

Answer 3

您可以在按钮后面输入textinput，并使按钮可视化为文本输入。

按下按钮时，将焦点放在textinput上，然后更新按钮文本。

我在这里举了一个例子。

from kivy.uix.textinput import TextInput
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.button import Button
from kivy.uix.label import Label
from kivy.clock import Clock
from kivy.app import App
from kivy import require

require('1.9.1')


class MyWidget(BoxLayout):
    def __init__(self,**kwargs):
        super(MyWidget,self).__init__(**kwargs)

        self.orientation = "vertical"

        self.cur = False

        self.textinput = TextInput(text='',halign="center",multiline=False)
        self.textinput.bind(text=self.on_text)

        self.button = Button(background_normal="",background_color=[0,0,0.1,1],font_size="40sp")
        self.button.bind(on_release=self.button_click)

        self.my_float_layout = FloatLayout()

        self.my_float_layout.add_widget(self.textinput)
        self.my_float_layout.add_widget(self.button)

        self.add_widget(Label(text="type text below",font_size="40sp"))
        self.add_widget(self.my_float_layout)

        Clock.schedule_interval(self.cursor, 0.5)


    def cursor(self,dt):          # function to visualize a cursor
        if self.textinput.focus:
            cur_pos = self.textinput.cursor[0]
            if not self.cur:
                self.button.text = self.textinput.text[:cur_pos] + "|" + self.textinput.text[cur_pos:]
                self.cur = True
            else:
                self.button.text = self.textinput.text[:cur_pos] + " " + self.textinput.text[cur_pos:]
                self.cur = False
        elif self.cur:
            self.button.text = self.textinput.text + " "
            self.cur = False



    def on_text(self, *args):     # function to set the button text
        self.button.text = self.textinput.text


    def button_click(self,*args): # function to focus the input
        self.textinput.focus = True



class MyApp(App):
    def build(self):
        return MyWidget()


if __name__ == "__main__":
    MyApp().run()

如何在Kivy文本输入中水平居中文本？

3 个答案: