Question

你好

 for (int i = 1; i < terasmasasayisi; i++)
        {

            var buttonteras = new Button
            {

                Text = i.ToString(),
                HeightRequest = 45,
                WidthRequest = 45,
                Margin = 5,
                CornerRadius = 100,
            };
            buttonteras.Clicked += butonteras; 
            teras.Children.Add(buttonteras);

           async void butonteras(object o, EventArgs args)

                {  

                secilenmasa = buttonteras.Text;
                secilenkonum = "Teras";
                await Navigation.PushModalAsync(new menu());

                }

            }

我以这种方式创建多个按钮，即terasmasasayisi用来计算数据库中有多少行

theese按钮将我定向到该页面上的另一页面，单击某个按钮后，我必须更改第一个按钮的背景色，我该怎么做？

Answer 1

您可以检查以下代码

使用MessagingCenter

 for (int i = 1; i < 10; i++)
        {

            var buttonteras = new Button
            {

                Text = i.ToString(),
                HeightRequest = 45,
                WidthRequest = 45,
                Margin = 5,
                CornerRadius = 100,
            };
            buttonteras.Clicked += butonteras;
            stack.Children.Add(buttonteras);



        }

        MessagingCenter.Subscribe<Object,View>(this,"click",(obj,view)=>
        {
            var childrens = stack.Children;

            for (int i = 0; i < childrens.Count; i++)
            {
                var element = childrens[i];

                var type = element.GetType();
                if (element == view)
                {
                    element.BackgroundColor = Color.Red;


                }
            }
        });

async void butonteras(object o, EventArgs args)
{
  //...
    var button = o as Button;
    await Navigation.PushModalAsync(new menu(button));


}

然后在菜单中，单击按钮。

View Element;

public menu(View element)
{
   Element = element;
   InitializeComponent();
}

MessagingCenter.Send<Object,View>(this, "click",Element);

Answer 2

MessagingCenter.Subscribe<siparis>(this, "click", (obj) =>
            {
            var childrens = bahce.Children;

            for (int i = 0; i < childrens.Count; i++)
            {

                    var element = childrens[i];

                    var type = element.GetType();

                    if (element.GetType().ToString() == "Xamarin.Forms.Button")
                    {
                        element.BackgroundColor = Color.Red;
                        break;

                    }
                }
            });

            async void bahcebuton(object o, EventArgs args)
            {


                secilenmasa = buttonbahce.Text;
                secilenkonum = "Bahçe";
                await Navigation.PushModalAsync(new menu());


            }

和其他形式

if (masterpage.secilenkonum == "Bahçe")
        {
            MessagingCenter.Send<siparis>(this, "click");
        }

现在它不会使所有按钮都变成红色，但现在仅使第一个按钮变成红色

如何在Xamarin的另一种表单上更改按钮背景颜色

2 个答案: