Используйте этот удобный класс, чтобы прокручивать фрейм, содержащий ваши виджеты. Выполните следующие шаги:
import tkinter as tk
from tkinter import ttk
class Scrollable(ttk.Frame):
"""
Make a frame scrollable with scrollbar on the right.
After adding or removing widgets to the scrollable frame,
call the update() method to refresh the scrollable area.
"""
def __init__(self, frame, width=16):
scrollbar = tk.Scrollbar(frame, width=width)
scrollbar.pack(side=tk.RIGHT, fill=tk.Y, expand=False)
self.canvas = tk.Canvas(frame, yscrollcommand=scrollbar.set)
self.canvas.pack(side=tk.LEFT, fill=tk.BOTH, expand=True)
scrollbar.config(command=self.canvas.yview)
self.canvas.bind('<Configure>', self.__fill_canvas)
# base class initialization
tk.Frame.__init__(self, frame)
# assign this obj (the inner frame) to the windows item of the canvas
self.windows_item = self.canvas.create_window(0,0, window=self, anchor=tk.NW)
def __fill_canvas(self, event):
"Enlarge the windows item to the canvas width"
canvas_width = event.width
self.canvas.itemconfig(self.windows_item, width = canvas_width)
def update(self):
"Update the canvas and the scrollregion"
self.update_idletasks()
self.canvas.config(scrollregion=self.canvas.bbox(self.windows_item))
root = tk.Tk()
header = ttk.Frame(root)
body = ttk.Frame(root)
footer = ttk.Frame(root)
header.pack()
body.pack()
footer.pack()
ttk.Label(header, text="The header").pack()
ttk.Label(footer, text="The Footer").pack()
scrollable_body = Scrollable(body, width=32)
for i in range(30):
ttk.Button(scrollable_body, text="I'm a button in the scrollable frame").grid()
scrollable_body.update()
root.mainloop()
Вы можете использовать UIKeyCommand
. Я тестировал на своем 10,5 "iPad Pro под управлением iOS 12.1.1, используя клавиатуру Bluetooth и приложение Swift Playgrounds версии 2.2.
Вот код игровой площадки:
import UIKit
import PlaygroundSupport
class ViewController: UIViewController {
override func loadView() {
let command = UIKeyCommand(input: "\u{8}", modifierFlags: .command, action: #selector(ViewController.handleKeyCommand), discoverabilityTitle: "Hello")
addKeyCommand(command)
let view = UIView(frame: CGRect(x: 0, y: 0, width: 300, height: 300))
view.contentMode = .topLeft
view.backgroundColor = .white
let stack = UIStackView()
stack.axis = .vertical
stack.spacing = 8
stack.alignment = .fill
stack.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(stack)
NSLayoutConstraint.activate([
view.leadingAnchor.constraint(equalTo: stack.leadingAnchor),
view.trailingAnchor.constraint(equalTo: stack.trailingAnchor),
view.topAnchor.constraint(equalTo: stack.topAnchor)])
let textField = UITextField(frame: CGRect(x: 20, y: 20, width: 260, height: 30))
textField.borderStyle = .roundedRect
textField.translatesAutoresizingMaskIntoConstraints = false
stack.addArrangedSubview(textField)
label.translatesAutoresizingMaskIntoConstraints = false
stack.addArrangedSubview(label)
self.view = view
}
@objc func handleKeyCommand(_ sender: UIKeyCommand) {
commandCount += 1
label.text = "\(commandCount)"
}
private var commandCount = 0
private let label = UILabel()
}
let vc = ViewController()
PlaygroundPage.current.liveView = vc
Нажмите на текст нажмите ⌘⌫ kbd>. Каждый раз, когда вы нажимаете его, счетчик в метке увеличивается на 1.