如何收听.NET MAUI（ios＆Android）中的音量按钮？ 我正在开发一个.NET MAUI应用程序，并希望检测用户何时按下iOS和Android上的音量上下按钮。我的目标是每当按下卷按钮时触发功能...

Question

// IVolumeButtonService.cs
public interface IVolumeButtonService
{
    event EventHandler VolumeButtonPressed;
}

秒，您可以创建一个服务来处理Android项目中的音量按钮。

using Android.Views;
using Microsoft.Maui.Controls.Compatibility.Platform.Android;

[assembly: Dependency(typeof(VolumeButtonService))]
public class VolumeButtonService : IVolumeButtonService
{
    public event EventHandler VolumeButtonPressed;

    public bool OnKeyDown(Keycode keyCode, KeyEvent e)
    {
        if (keyCode == Keycode.VolumeUp || keyCode == Keycode.VolumeDown)
        {
            VolumeButtonPressed?.Invoke(this, EventArgs.Empty);
            return true;
        }
        return false;
    }
}

，然后您需要在主动脉中覆盖onekeydown和onkeyup方法。

public override bool OnKeyDown(Keycode keyCode, KeyEvent e)
{
    var volumeService = DependencyService.Get<IVolumeButtonService>() as VolumeButtonService;
    if (volumeService != null && volumeService.OnKeyDown(keyCode, e))
    {
        return true;
    }
    return base.OnKeyDown(keyCode, e);
}

Answer 1

在您的iOS项目中，请创建一个服务来处理音量按钮按下。

using AVFoundation;
using MediaPlayer;
using UIKit;

[assembly: Dependency(typeof(VolumeButtonService))]
public class VolumeButtonService : IVolumeButtonService
{
    public event EventHandler VolumeButtonPressed;

    public VolumeButtonService()
    {
        var volumeView = new MPVolumeView();
        volumeView.ShowsVolumeSlider = false;
        volumeView.ShowsRouteButton = false;
        UIApplication.SharedApplication.KeyWindow.AddSubview(volumeView);

        foreach (var view in volumeView.Subviews)
        {
            if (view is UISlider slider)
            {
                slider.ValueChanged += (sender, e) =>
                {
                    VolumeButtonPressed?.Invoke(this, EventArgs.Empty);
                };
            }
        }
    }
}

在您的.NET MAUI项目中，使用服务来收听音量按钮按下。

public MainPage()
    {
        InitializeComponent();
        var volumeService = DependencyService.Get<IVolumeButtonService>();
        volumeService.VolumeButtonPressed += OnVolumeButtonPressed;
    }

    private void OnVolumeButtonPressed(object sender, EventArgs e)
    {
        DisplayAlert("Volume Button Pressed", "A volume button was pressed!", "OK");
    }