[X.Andriod] 動態產生 CheckBox

練習在 LinearLayout 內動態新增 CheckBox，勾選時會顯示目前控件和全部控件狀態

DynamicAdd.axml 內只有一個 LinearLayout

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:id="@+id/Layout" />

DynamicActivity.cs

namespace CheckBoxBase
{
    [Activity(Label = "DynamicActivity", MainLauncher = true)]
    public class DynamicActivity : Activity
    {
        protected override void OnCreate(Bundle savedInstanceState)
        {
            base.OnCreate(savedInstanceState);
            SetContentView(Resource.Layout.DynamicAdd);

            // 動態產生 CheckBox 
            LinearLayout layout = FindViewById<LinearLayout>(Resource.Id.Layout);
            for (int i = 0; i < 5; i++)
            {
                CheckBox cb = new CheckBox(this);
                cb.Text = $"Dynamic{i}";
                cb.CheckedChange += Cb_CheckedChange;
                layout.AddView(cb);
            }
        }

        private void Cb_CheckedChange(object sender, CompoundButton.CheckedChangeEventArgs e)
        {
            LinearLayout layout = FindViewById<LinearLayout>(Resource.Id.Layout);
            StringBuilder sb = new StringBuilder();

            sb.AppendLine($"目前勾選： {((CheckBox)sender).Text}，狀態為：{e.IsChecked}");
            sb.AppendLine("---------------------------");
            sb.AppendLine("顯示全部 CheckBox 狀態");

            int ctls = layout.ChildCount;
            for (int i = 0; i < ctls; i++)
            {
                View v = layout.GetChildAt(i);
                if ((v is CheckBox) == false) continue;
                CheckBox cb = v as CheckBox;
                sb.AppendLine(cb.Text + "狀態為" + (cb.Checked == true ? "已勾選" : "未勾選"));
            }

            Toast.MakeText(this, sb.ToString(), ToastLength.Short).Show();
        }
    }
}

沒有 ofType() 可以使用就要多寫點 Code 來判斷是不是 CheckBox 控件

參考資料
• Android User Interface Design: Linear Layouts
  
• How to create UI elements dynamically
• Dynamically Create View Elements - Android Example
• 版面配置