package example.com.myapplication;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.content.DialogInterface;
import android.os.Bundle;
import android.widget.Toast;
public class MainActivity extends Activity {
  //声明选中项变量
  private int selectedCityIndex = 0;
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    //定义城市数组
    final String[] arrayCity = new String[] { "杭州", "纽约", "威尼斯", "北海道" };
    //实例化AlertDialog对话框
    Dialog alertDialog = new AlertDialog.Builder(this)
        .setTitle("你最喜欢哪个地方？")            //设置标题
        .setIcon(R.mipmap.ic_launcher)        //设置图标
        //设置对话框显示一个单选List，指定默认选中项，同时设置监听事件处理
        .setSingleChoiceItems(arrayCity, 0, new DialogInterface.OnClickListener() {
          @Override
          public void onClick(DialogInterface dialog, int which) {
            selectedCityIndex = which;        //选中项的索引保存到选中项变量
          }
        })
        //添加取消按钮并增加监听处理
        .setNegativeButton("取消", new DialogInterface.OnClickListener() {
          @Override
          public void onClick(DialogInterface dialog, int which) {
            // TODO Auto-generated method stub
          }
        })
        //添加确定按钮并增加监听处理
        .setPositiveButton("确认", new DialogInterface.OnClickListener() {
          @Override
          public void onClick(DialogInterface dialog, int which) {
            Toast.makeText(getApplication(), arrayCity[selectedCityIndex], Toast.LENGTH_SHORT).show();
          }
        })
        .create();
    alertDialog.show();
  }
}

package example.com.myapplication;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.content.DialogInterface;
import android.os.Bundle;
import android.widget.Toast;
public class MainActivity extends Activity {
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    //定义运动数组
    final String[] arraySport = new String[] { "足球", "篮球", "网球", "乒乓球" };
    final boolean[] arraySportSelected = new boolean[] {false, false, false, false};
    //实例化AlertDialog对话框
    Dialog alertDialog = new AlertDialog.Builder(this)
        .setTitle("你喜欢哪些运动？")            //设置标题
        .setIcon(R.mipmap.ic_launcher)        //设置图标
        //设置对话框显示一个复选List，指定默认选中项，同时设置监听事件处理
        .setMultiChoiceItems(arraySport, arraySportSelected,
            new DialogInterface.OnMultiChoiceClickListener() {
          @Override
          public void onClick(DialogInterface dialog, int which, boolean isChecked) {
            arraySportSelected[which] = isChecked;       //选中项的布尔真假保存到选中项变量
          }
        })
        //添加取消按钮并增加监听处理
        .setPositiveButton("确认", new DialogInterface.OnClickListener() {
          @Override
          public void onClick(DialogInterface dialog, int which) {
            StringBuilder stringBuilder = new StringBuilder();
            for (int i = 0; i < arraySportSelected.length; i++) {
              if (arraySportSelected[i] == true){
                stringBuilder.append(arraySport[i] + "、");
              }
            }
            Toast.makeText(getApplication(), stringBuilder.toString(), Toast.LENGTH_SHORT).show();
          }
        })
        //添加确定按钮并增加监听处理
        .setNegativeButton("取消", new DialogInterface.OnClickListener() {
          @Override
          public void onClick(DialogInterface dialog, int which) {
            // TODO Auto-generated method stub
          }
        })
        .create();
    alertDialog.show();
  }
}