没有这样的文件或目录-如何修复? 导入android.support.v4.app.ActivityCompat; 导入android.support.v7.app.AppActivity; 导入android.view.Menu; 导入android.view.MenuInflater; 导入android.view.MenuItem; 导入android.widget.Toast; 导入org.osmdroid.config.Configuration; 导入org.osmdroid.util.GeoPoint; 导入org.osmdroid.views.MapView; 导入org.osmdroid.views.overlay.itemizedictionoverlay; 导入org.osmdroid.views.overlay.OverlayItem; 导入java.io.BufferedReader; 导入java.io.FileReader; 导入java.io.FileWriter; 导入java.io.IOException; 导入java.io.PrintWriter; 导入java.util.ArrayList; 公共类MainActivity扩展了活动{ 地图视图mv; 项目法令覆盖项目; ItemizedEdiconOverlay.OnItemGestureListener标记EstureListener; 创建时受保护的void(Bundle savedInstanceState){ super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); items=new itemizedictionoverlay(this,new ArrayList(),null); Configuration.getInstance().load(this,PreferenceManager.getDefaultSharedReferences(this)); LocationManager mgr=(LocationManager)getSystemService(Context.LOCATION\u服务); if(ActivityCompat.checkSelfPermission(this,Manifest.permission.ACCESS\u FINE\u LOCATION)!=PackageManager.permission\u已授予和&ActivityCompat.checkSelfPermission(this,Manifest.permission.ACCESS\u LOCATION)!=PackageManager.permission\u已授予){ 考虑到呼叫 //ActivityCompat#请求权限 //在此处请求缺少的权限,然后覆盖 //public void onRequestPermissionsResult(int-requestCode,字符串[]权限, //int[]格兰特结果) //处理用户授予权限的情况。请参阅文档 //对于ActivityCompat,请请求权限以获取更多详细信息。 返回; } 经理requestLocationUpdates(LocationManager.GPS_提供程序,0,0,(LocationListener)this); mv=(MapView)findViewById(R.id.mvID); mv.SetBuiltinzoomControl(真); mv.getController().setZoom(12); mv.getController().setCenter(新地质点(50.907703,-1.401472)); } 已更改位置上的公共无效(位置newLoc){ Toast.makeText (这是“位置=”+ newLoc.getLatitude()+“”+ newLoc.getLongitude(),Toast.LENGTH_LONG).show(); mv.getController().setCenter(新地理点(newLoc.getLatitude(),newLoc.getLongitude()); } 公共无效onProviderDisabled(字符串提供程序) { Toast.makeText(此“提供程序”+提供程序+ “禁用”,Toast.LENGTH_LONG.show(); } 公共无效onProviderEnabled(字符串提供程序) { Toast.makeText(此“提供程序”+提供程序+ “已启用”,Toast.LENGTH_LONG.show(); } public void onStatusChanged(字符串提供程序、int状态、Bundle extra) { Toast.makeText(此“状态已更改:”+状态, Toast.LENGTH_LONG).show(); } @凌驾 公共布尔onCreateOptions菜单(菜单){ MenuInflater充气机=getMenuInflater(); 充气机。充气(右菜单,菜单); 返回true; } @凌驾 公共布尔值onOptionsItemSelected(菜单项项){ if(item.getItemId()==R.id.newResID){ Intent Intent=新Intent(这个,AddPlace.class); startActivityForResult(意向,0); 返回true; } if(item.getItemId()==R.id.saveResID){ 试一试{ 印刷撰稿人= 新的PrintWriter(新的FileWriter(Environment.getExternalStorageDirectory().getAbsolutePath()+“/data.csv”,true)); 对于(int i=0;i
在这一行中,您尝试打开一个文件。该文件在模拟器上不存在,因此无法打开。Android Studio没有显示任何错误,因为在编译期间没有问题,因为如果该文件存在,应用程序将正常运行。您是否有权限“Android.permission.WRITE\u EXTERNAL\u STORAGE”?试着在这里多放一点你的航海日志。@Taier找到了。是的,我已经把它写在我的舱单上了file@JackNash您需要在清单中设置权限,并询问用户对上述marshamallowso的运行时权限。如果我需要此文件作为我代码的一部分,我会不能对该文件进行EUMATE吗?首先,我不会推荐我nd将数据存储在文件中,但如果确实必须将其存储在文件中,则必须确保该文件始终存在,或者在访问该文件之前进行检查以查看该文件是否存在,如果不存在,则向用户显示正确的错误消息没有这样的文件或目录-如何修复? 导入android.support.v4.app.ActivityCompat; 导入android.support.v7.app.AppActivity; 导入android.view.Menu; 导入android.view.MenuInflater; 导入android.view.MenuItem; 导入android.widget.Toast; 导入org.osmdroid.config.Configuration; 导入org.osmdroid.util.GeoPoint; 导入org.osmdroid.views.MapView; 导入org.osmdroid.views.overlay.itemizedictionoverlay; 导入org.osmdroid.views.overlay.OverlayItem; 导入java.io.BufferedReader; 导入java.io.FileReader; 导入java.io.FileWriter; 导入java.io.IOException; 导入java.io.PrintWriter; 导入java.util.ArrayList; 公共类MainActivity扩展了活动{ 地图视图mv; 项目法令覆盖项目; ItemizedEdiconOverlay.OnItemGestureListener标记EstureListener; 创建时受保护的void(Bundle savedInstanceState){ super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); items=new itemizedictionoverlay(this,new ArrayList(),null); Configuration.getInstance().load(this,PreferenceManager.getDefaultSharedReferences(this)); LocationManager mgr=(LocationManager)getSystemService(Context.LOCATION\u服务); if(ActivityCompat.checkSelfPermission(this,Manifest.permission.ACCESS\u FINE\u LOCATION)!=PackageManager.permission\u已授予和&ActivityCompat.checkSelfPermission(this,Manifest.permission.ACCESS\u LOCATION)!=PackageManager.permission\u已授予){ 考虑到呼叫 //ActivityCompat#请求权限 //在此处请求缺少的权限,然后覆盖 //public void onRequestPermissionsResult(int-requestCode,字符串[]权限, //int[]格兰特结果) //处理用户授予权限的情况。请参阅文档 //对于ActivityCompat,请请求权限以获取更多详细信息。 返回; } 经理requestLocationUpdates(LocationManager.GPS_提供程序,0,0,(LocationListener)this); mv=(MapView)findViewById(R.id.mvID); mv.SetBuiltinzoomControl(真); mv.getController().setZoom(12); mv.getController().setCenter(新地质点(50.907703,-1.401472)); } 已更改位置上的公共无效(位置newLoc){ Toast.makeText (这是“位置=”+ newLoc.getLatitude()+“”+ newLoc.getLongitude(),Toast.LENGTH_LONG).show(); mv.getController().setCenter(新地理点(newLoc.getLatitude(),newLoc.getLongitude()); } 公共无效onProviderDisabled(字符串提供程序) { Toast.makeText(此“提供程序”+提供程序+ “禁用”,Toast.LENGTH_LONG.show(); } 公共无效onProviderEnabled(字符串提供程序) { Toast.makeText(此“提供程序”+提供程序+ “已启用”,Toast.LENGTH_LONG.show(); } public void onStatusChanged(字符串提供程序、int状态、Bundle extra) { Toast.makeText(此“状态已更改:”+状态, Toast.LENGTH_LONG).show(); } @凌驾 公共布尔onCreateOptions菜单(菜单){ MenuInflater充气机=getMenuInflater(); 充气机。充气(右菜单,菜单); 返回true; } @凌驾 公共布尔值onOptionsItemSelected(菜单项项){ if(item.getItemId()==R.id.newResID){ Intent Intent=新Intent(这个,AddPlace.class); startActivityForResult(意向,0); 返回true; } if(item.getItemId()==R.id.saveResID){ 试一试{ 印刷撰稿人= 新的PrintWriter(新的FileWriter(Environment.getExternalStorageDirectory().getAbsolutePath()+“/data.csv”,true)); 对于(int i=0;i,java,android,enoent,Java,Android,Enoent,在这一行中,您尝试打开一个文件。该文件在模拟器上不存在,因此无法打开。Android Studio没有显示任何错误,因为在编译期间没有问题,因为如果该文件存在,应用程序将正常运行。您是否有权限“Android.permission.WRITE\u EXTERNAL\u STORAGE”?试着在这里多放一点你的航海日志。@Taier找到了。是的,我已经把它写在我的舱单上了file@JackNash您需要在清单中设置权限,并询问用户对上述marshamallowso的运行时权限。如果我需要此文件作为
import android.support.v4.app.ActivityCompat;
import android.support.v7.app.AppCompatActivity;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.widget.Toast;
import org.osmdroid.config.Configuration;
import org.osmdroid.util.GeoPoint;
import org.osmdroid.views.MapView;
import org.osmdroid.views.overlay.ItemizedIconOverlay;
import org.osmdroid.views.overlay.OverlayItem;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
public class MainActivity extends Activity {
MapView mv;
ItemizedIconOverlay<OverlayItem> items;
ItemizedIconOverlay.OnItemGestureListener<OverlayItem> markerGestureListener;
protected void OnCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
items = new ItemizedIconOverlay<OverlayItem>(this, new ArrayList<OverlayItem>(), null);
Configuration.getInstance().load(this, PreferenceManager.getDefaultSharedPreferences(this));
LocationManager mgr = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return;
}
mgr.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, (LocationListener) this);
mv = (MapView) findViewById(R.id.mvID);
mv.setBuiltInZoomControls(true);
mv.getController().setZoom(12);
mv.getController().setCenter(new GeoPoint(50.907703,-1.401472));
}
public void onLocationChanged(Location newLoc) {
Toast.makeText
(this, "Location=" +
newLoc.getLatitude() + " " +
newLoc.getLongitude(), Toast.LENGTH_LONG).show();
mv.getController().setCenter(new GeoPoint(newLoc.getLatitude(), newLoc.getLongitude()));
}
public void onProviderDisabled(String provider)
{
Toast.makeText(this, "Provider " + provider +
" disabled", Toast.LENGTH_LONG).show();
}
public void onProviderEnabled(String provider)
{
Toast.makeText(this, "Provider " + provider +
" enabled", Toast.LENGTH_LONG).show();
}
public void onStatusChanged(String provider,int status,Bundle extras)
{
Toast.makeText(this, "Status changed: " + status,
Toast.LENGTH_LONG).show();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.menu, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
if (item.getItemId() == R.id.newResID){
Intent intent = new Intent (this, AddPlace.class);
startActivityForResult(intent, 0);
return true;
}
if (item.getItemId() == R.id.saveResID){
try {
PrintWriter pw =
new PrintWriter(new FileWriter(Environment.getExternalStorageDirectory().getAbsolutePath() + "/data.csv", true));
for(int i=0; i<items.size(); i++){
OverlayItem itm = items.getItem(i);
pw.println(itm.getTitle()+","+itm.getSnippet()+","+itm.getPoint().getLatitude()+","+itm.getPoint().getLongitude());
}
pw.close();
}
catch (IOException e){
new AlertDialog.Builder(this).setMessage("ERROR Loading:" + e).
setPositiveButton("OK", null).show();
}
}
if (item.getItemId() == R.id.setPrefID){
Intent intent = new Intent (this, PreferencesActivity.class);
startActivityForResult(intent, 1);
return true;
}
if (item.getItemId() == R.id.setPrefID){
try
{
BufferedReader reader = new BufferedReader(new FileReader(Environment.getExternalStorageDirectory().getAbsolutePath() + "/data.csv"));
String line;
while((line = reader.readLine()) != null)
{
String[] components = line.split(",");
if(components.length==4)
{
Double lat = Double.valueOf(components[2]).doubleValue();
Double lon = Double.valueOf(components[3]).doubleValue();
OverlayItem itm = new OverlayItem(components[0], components[1], new GeoPoint(lat, lon));
items.addItem(itm);
}
}
}
catch(IOException e)
{
new AlertDialog.Builder(this).setMessage("ERROR Loading:" + e).
setPositiveButton("OK", null).show();
}
return true;
}
return false;
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == 0){
if (resultCode == RESULT_OK){
Bundle extras = data.getExtras();
String name = data.getExtras().getString("com.example.a2colej34.place_name_input");
String address = data.getExtras().getString("com.example.a2colej34.place_type_input");
String cuisine = data.getExtras().getString("com.example.a2colej34.place_price_input");
double lat = mv.getMapCenter().getLatitude();
double lon = mv.getMapCenter().getLongitude();
items = new ItemizedIconOverlay<OverlayItem>(this, new ArrayList<OverlayItem>(),markerGestureListener);
OverlayItem newRestaurant = new OverlayItem(name+ " ", address+" "+cuisine+" ", new GeoPoint(lat,lon));
items.addItem(newRestaurant);
mv.getOverlays().add(items);
SharedPreferences customPrefs = PreferenceManager.getDefaultSharedPreferences(getApplicationContext());
boolean autosave = customPrefs.getBoolean("autosave", true);
if(autosave){
try {
PrintWriter pw =
new PrintWriter(new FileWriter(Environment.getExternalStorageDirectory().getAbsolutePath() + "/data.csv", true));
for(int i=0; i<items.size(); i++){
OverlayItem itm = items.getItem(i);
pw.println(itm.getTitle()+","+itm.getSnippet()+","+itm.getPoint().getLatitude()+","+itm.getPoint().getLongitude());
}
pw.close();
}
catch (IOException e){
new AlertDialog.Builder(this).setMessage("ERROR Loading: " + e).
setPositiveButton("OK", null).show();
}
}
}
}
}
@Override
protected void onStart()
{
super.onStart();
try
{
BufferedReader reader = new BufferedReader(new FileReader(Environment.getExternalStorageDirectory().getAbsolutePath() + "/data.csv"));
String line;
while((line = reader.readLine()) != null)
{
String[] components = line.split(",");
if(components.length==4)
{
Double lat = Double.valueOf(components[2]).doubleValue();
Double lon = Double.valueOf(components[3]).doubleValue();
OverlayItem itm = new OverlayItem(components[0], components[1], new GeoPoint(lat, lon));
items.addItem(itm);
}
}
}
catch(IOException e)
{
new AlertDialog.Builder(this).setMessage("ERROR Loading: " + e).
setPositiveButton("OK", null).show();
}
}
}
BufferedReader reader = new BufferedReader(new FileReader(Environment.getExternalStorageDirectory().getAbsolutePath() + "/data.csv"));