5.Xamarin.Forms里按钮的实现

来源：互联网发布：xbox one 移动网络 dns 编辑：程序博客网时间：2024/09/21 09:28

其实Xamarin.Forms中的按钮的用发和WPF的几乎一样。
先看看这个吧，创建一个按钮并添加点击事件。

class aaa:ContentPage    {        StackLayout a = new StackLayout();        public aaa()        {            Button b = new Button            {                Text = "button"            };            b.Clicked += B_Clicked;            Content = new StackLayout            {                Children =                {                    b,                    new ScrollView                    {                        VerticalOptions=LayoutOptions.FillAndExpand,                        Content=a                    }                }            };        }        private void B_Clicked(object sender, EventArgs e)        {            a.Children.Add(new Label            {                Text = "Clicked at" + DateTime.Now.ToString("T")            });        }    }

最终的效果
这里写图片描述

当然也可以在代码中使用Lambda表达式。如下：

    class aaa:ContentPage    {        StackLayout a = new StackLayout();        public aaa()        {            Button b = new Button            {                Text = "button"            };            b.Clicked += (s, e) =>             {                 a.Children.Add(new Label                 {                     Text = "Clicked at" + DateTime.Now.ToString("T")                 });             };            Content = new StackLayout            {                Children =                {                    b,                    new ScrollView                    {                        VerticalOptions=LayoutOptions.FillAndExpand,                        Content=a                    }                }            };        }    }

以下是Button可以设置的属性：

FontFamily FontSize FontAttributes TextColor BorderColor BorderWidth BorderRadius Image

下面展示的是两个按钮如何使用同一个事件，做不同的事：

 class aaa:ContentPage    {        StackLayout a = new StackLayout();        Button b = new Button        {            Text = "Add",            HorizontalOptions = LayoutOptions.CenterAndExpand        };        Button c = new Button        {            Text = "Remove",            HorizontalOptions = LayoutOptions.CenterAndExpand        };        public aaa()        {            b.Clicked += B_Clicked;            c.Clicked += B_Clicked;            Content = new StackLayout            {                Children =                {                    new StackLayout                    {                        Orientation=StackOrientation.Horizontal,                        Children=                        {                            b,c                        }                    },                    new ScrollView                    {                        VerticalOptions=LayoutOptions.FillAndExpand,                        Content=a                    }                }            };        }        private void B_Clicked(object sender, EventArgs e)        {            Button button = (Button)sender;            if (button == b)            {                a.Children.Add(new Label                {                    Text = "Clicked at" + DateTime.Now.ToString("T")                });            }            else            {                a.Children.RemoveAt(0);            }            c.IsEnabled = a.Children.Count > 0;        }    }

这里写图片描述

1 0