有人可以帮我转换一下：
var l = List(1,2,"3")
进入这个：
var lNew = List(1,2,3)
这意味着我想转换一个带有部分整数的列表和部分整数作为字符串输入（例如＆＃34; 27＆＃34;）到一个只有整数的新列表。问题是你不能在列表[任意]上使用.toInt。
非常感谢提前！
答案 0 :(得分：19)
这应该是足够的解决方案：
l.map(_.toString).map(_.toInt)
编辑：
关注soulcheck suggestion，甚至更好：
l.map(_.toString.toInt)
答案 1 :(得分：2)
从package com.example.rajat.fragments;
import android.app.Fragment;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
public class FragmentClass extends Fragment {
Button button;
int count;
String key1 = "counter";
Communicator comm;
int key;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Log.i("onCreate", "onCreate() called");
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
return inflater.inflate(R.layout.fragment_activity, container, false);
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
comm = (Communicator) getActivity();
button = (Button) getActivity().findViewById(R.id.button);
if (savedInstanceState != null) {
count = savedInstanceState.getInt(key1, 1);
Log.e("onCreate", "onActivityCreated() called value of count :" + count);
}
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
count++;
key = count;
Log.e("onCreate", "count value : " + count);
comm.respond("The button is clicked " + count + " times");
}
});
}
@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
super.onSaveInstanceState(savedInstanceState);
savedInstanceState.putInt(key1, count);
Log.d("onCreate", "onSavedInstanceState() called value of count :" + count);
}
开始并引入String#toIntOption，如果需要的话，我们可以使@liosedhel's answer更加安全：
Scala 2.13