在if语句之后识别扫描仪中的新行

Question

我对android有点陌生，我一直对scanner类(尤其是.newline())有问题，因为我无法让它在以下代码中工作。java只扫描文档中的所有内容，而不检查行

package com.cal.omida.calupdater;
import android.content.DialogInterface;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import java.util.Scanner;
public class MainActivity extends AppCompatActivity {
private TextView textv;
private Button submitButton;
private String TAG = "got here";
private String[] stringsarray = {"empty","empty","empty","empty","empty","empty","empty","empty","empty","empty","empty"};
private String exp = null;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
textv = (TextView) findViewById(R.id.mainentry);
submitButton = (Button) findViewById(R.id.process);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
submitButton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
String temp = textv.getText().toString();
String main = removeTab(temp);
Scanner scanner = new Scanner(main);
String[] finalString = scannerclass(scanner);
Log.d("found", main);
for (int io = 0; io<11;io++){
exp+=finalString[io]+"n";
}
alert(exp,scanner);
}
});
}
private String[] scannerclass(Scanner scanner){
scanner.useDelimiter(";");
int i = 0;
while (scanner.hasNext()) {
String text = scanner.next();
stringsarray[i] = text;
i++;
}
return stringsarray;
}
private void alert(String text, final Scanner scanner){
AlertDialog alertDialog = new AlertDialog.Builder(MainActivity.this).create();
alertDialog.setTitle("Alert");
alertDialog.setMessage(text);
alertDialog.setButton(AlertDialog.BUTTON_POSITIVE, "Add to cal",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
//todo add to cal function
exp=null;
if (scanner.hasNextLine()){
scanner.nextLine();
String[] finalString = scannerclass(scanner);
for (int io = 0; io<11;io++){
exp+=finalString[io]+"n";
}
alert(exp,scanner);
}
}
});
alertDialog.setButton(AlertDialog.BUTTON_NEGATIVE, "Cancel",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.dismiss();
exp=null;
}
});
alertDialog.show();
}
private String removeTab(String main) {
String main2 = main.replace("t",";");
return main2;
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}

只是为了稍微澄清一下我的代码：我有一个由11部分组成的行，用"；"分隔。我想扫描行的每一部分，将其放入一个数组中，使用警报对话框检查数据，如果是肯定的，将其添加到我的日历中(仍在开发中)，然后扫描下一行。我的问题是：如果我输入的零件少于11个，扫描仪会继续到下一行。有没有什么方法可以阻止这种情况，让它只扫描它所在的线路，而不继续到下一条？

Answer 1

解决方案是使用一个扫描仪获取每一行，然后使用第二个扫描仪分离每一行

例如：

String main = /*something*/;
Scanner lineScanner = new Scanner(main); // will scan each line, separated by a newline
while(lineScanner.hasNextLine()){
Scanner semicolonSeparatedScanner = new Scanner(lineScanner.nextLine());
/* work from here */
}

请注意，您甚至可以使用String.split:进一步简化代码

while(lineScanner.hasNextLine()){
String[] semicolonSeparatedText = lineScanner.nextLine().split(";");
}