Checkbox label is now Into<String>

[0x7CFE]

This PR allows checkbox labels to be dynamically modified depending on the business logic.

For example:

use iced::{Sandbox, Settings, Text, Align, Column};

fn main() {
    CheckUi::run(Settings::default());
}

#[derive(Default)]
struct CheckUi {
    checks: Vec<bool>,
}

#[derive(Debug, Copy, Clone)]
enum CheckMessage {
    InputChecked(usize, bool),
}

impl Sandbox for CheckUi {
    type Message = CheckMessage;

    fn new() -> Self {
        Self {
            checks: (0..10).map(|_| false).collect(),
            ..Default::default()
        }
    }
    
    fn title(&self) -> String { "Dynamic checkbox label".into() }
    
    fn update(&mut self, message: Self::Message) {
        match message {
            CheckMessage::InputChecked(index, value) => self.checks[index] = value,
        }
    }

    fn view(&mut self) -> iced::Element<'_, Self::Message> {
        let mut inputs = Column::new()
            .height(iced::Length::Fill)
            .width(iced::Length::Fill)
            .align_items(Align::Start);

        for (index, checked) in self.checks.iter().enumerate() {
            inputs = inputs.push(
                iced::Checkbox::new(
                    *checked,
                    format!("Checkbox {}", index),
                    move |state| CheckMessage::InputChecked(index, state)
                )
                .width(iced::Length::Fill)
            );
        }

        inputs.into()
    }
}

[hecrj]

Cool! I forgot about changing this.

Could you do the same for the Radio widget?

[0x7CFE]

Could you do the same for the Radio widget?

Done.

By the way, would you mind refactoring the text in the same manner as it is done for normal push button? I mean so that Checkbox would accept content instead of label. For example that would allow editing text styles without need to delegate a ton of methods.

When working on my project I already hacked an option to set the color of the text.

[hecrj]

Thanks!

Eventually, I believe we will change Checkbox to only be the actual checkbox without any text. Also, Radio needs to change to address #71.