Android ArrayList、Map.Entry存在问题<;字符串(>;)进入
我这行有多个错误Android ArrayList、Map.Entry存在问题<;字符串(>;)进入,android,Android,我这行有多个错误 for (Map.Entry<String, ?>) entry : settings.getAll().entrySet()) list.add(entry.getValue().toString()); for(Map.Entry)条目:settings.getAll().entrySet())list.add(Entry.getValue().toString()); 不是语句,表达式开头非法,此处不允许变量声明 我们在课堂上做了这个,我的意思是教授让我
for (Map.Entry<String, ?>) entry : settings.getAll().entrySet()) list.add(entry.getValue().toString());
for(Map.Entry)条目:settings.getAll().entrySet())list.add(Entry.getValue().toString());
不是语句,表达式开头非法,此处不允许变量声明
我们在课堂上做了这个,我的意思是教授让我们在大屏幕上写整个代码。。。
有人知道怎么修这条线吗?
我不太擅长android studio,因为我的视力很差,所以有时在屏幕上编写代码时会出错:(
完整代码(如果需要):
package com.example.student.projekt_7;
import android.content.SharedPreferences;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Locale;
import java.util.Map;
public class MainActivity extends AppCompatActivity {
ListView listView;
TextView textView;
SharedPreferences settings;
SharedPreferences.Editor editor;
int counter;
private void initializeResources(){
listView = (ListView) findViewById(R.id.ListView);
textView = (TextView) findViewById(R.id.textView);
settings = getPreferences (MODE_PRIVATE);
editor = settings.edit();
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initializeResources();
updateInterface();
}
private void updateInterface(){
ArrayList<String> list = getSettings();
setListData(list);
counter = list.size();
textView.setText(String.valueOf(counter));
}
private ArrayList<String> getSettings()
{
ArrayList<String> list = new ArrayList<>();
for (Map.Entry<String, ?>) entry : settings.getAll().entrySet()) list.add(entry.getValue().toString());
return list;
}
private void setListData(ArrayList<String> data)
{
listView.setAdapter(new ArrayAdapter<>(
getApplicationContext(),
android.R.layout.simple_list_item_1,
data));
}
public void addData (View view)
{
addSetting(String.valueOf(++counter));
updateInterface();
}
public void delData (View view)
{
clearSettings();
updateInterface();
}
private void addSetting(String key)
{
editor.putString(key, getDataTime());
editor.commit();
}
private void clearSettings()
{
}
private String getDateTime()
{
long currentTimeMillis = System.currentTimeMillis();
Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(currentTimeMillis);
int year = calendar.get(Calendar.YEAR);
int month = calendar.get(Calendar.MONTH)+1;
int day = calendar.get(Calendar.DAY_OF_MONTH);
int hours = calendar.get(Calendar.HOUR);
int minutes = calendar.get(Calendar.MINUTE);
int seconds = calendar.get(Calendar.SECOND);
return String.format(Locale.ENGLISH, "%04d-%02d-%02d %02d:%02d:%02d:%03d",
year, month, day, hours, minutes, seconds,currentTimeMillis%1000);
}
}
package com.example.student.projekt_7;
导入android.content.SharedReferences;
导入android.support.v7.app.AppActivity;
导入android.os.Bundle;
导入android.view.view;
导入android.widget.ArrayAdapter;
导入android.widget.ListView;
导入android.widget.TextView;
导入java.util.ArrayList;
导入java.util.Calendar;
导入java.util.Locale;
导入java.util.Map;
公共类MainActivity扩展了AppCompatActivity{
列表视图列表视图;
文本视图文本视图;
共享引用设置;
SharedReferences.Editor;
整数计数器;
私有void initializeResources(){
listView=(listView)findViewById(R.id.listView);
textView=(textView)findViewById(R.id.textView);
设置=获取首选项(模式\私有);
editor=settings.edit();
}
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
初始化资源();
updateInterface();
}
私有void updateInterface(){
ArrayList=getSettings();
setListData(列表);
计数器=list.size();
textView.setText(String.valueOf(counter));
}
私有ArrayList getSettings()
{
ArrayList=新建ArrayList();
对于(Map.Entry)条目:settings.getAll().entrySet())list.add(Entry.getValue().toString());
退货清单;
}
私有void setListData(ArrayList数据)
{
setAdapter(新的ArrayAdapter(
getApplicationContext(),
android.R.layout.simple\u list\u item\u 1,
数据);
}
公共void addData(视图)
{
addSetting(String.valueOf(++计数器));
updateInterface();
}
公共void delData(视图)
{
clearSettings();
updateInterface();
}
私有void addSetting(字符串键)
{
putString(key,getDataTime());
commit();
}
私人无效清除设置()
{
}
私有字符串getDateTime()
{
long currentTimeMillis=System.currentTimeMillis();
日历=Calendar.getInstance();
日历。setTimeInMillis(currentTimeMillis);
int year=calendar.get(calendar.year);
int month=calendar.get(calendar.month)+1;
int day=calendar.get(calendar.day/u月);
int hours=calendar.get(calendar.HOUR);
int minutes=calendar.get(calendar.minutes);
int seconds=calendar.get(calendar.SECOND);
返回String.format(Locale.ENGLISH,“%04d-%02d-%02d%02d:%02d:%02d:%03d”,
年、月、日、时、分、秒、currentTimeMillis%1000);
}
}
您的循环中有一个杂散的)
:
for (Map.Entry<String, ?>) entry : settings.getAll().entrySet())
^
(Map.Entry)项的settings.getAll().entrySet())
^
一旦你删除,你应该是所有设置