如何正确使用AsyncTask？
How to use AsyncTask correctly?
这种情况下如何正确使用Asynctask？
所以在某些应用程序中我遇到了异常：“android.os.NetworkOnMainThreadException”
解决它的一种方法是使用 Asynctask
但是在这种情况下如何使用它呢？
package com.mycompany.myapp;
import android.app.*;
import android.os.*;
import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v7.app.AppCompatActivity;
import android.widget.FrameLayout;
import java.io.*;
import java.net.*;
import android.content.Intent;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.EditText;
import android.widget.Toast;
import android.view.View;
import android.text.Html;
import java.util.Scanner;
import com.mycompany.myapp.client.HCUser;
import com.mycompany.myapp.common.*;
import android.content.SharedPreferences;
import android.content.Context;
import com.mycompany.myapp.common.constants.*;
import java.util.ArrayList;
import Misc.Settings;
import com.mycompany.myapp.client.*;
import java.nio.channels.SocketChannel;
import com.mycompany.myapp.client.packages.tcp.P2;
import com.mycompany.myapp.common.packages.tcp.HPackage;
import com.mycompany.myapp.common.serialization.HPackageSerializer;
public class MainActivity extends AppCompatActivity implements Runnable
{
FrameLayout simpleFrameLayout;
TabLayout tabLayout;
static Socket sock = new Socket();
static OutputStream out = null;
static DataInputStream dIn;
FirstFragment f = new FirstFragment();
SecondFragment s = new SecondFragment();
private HCUser user;
private Thread reader;
private Timer updateTimer;
private boolean running;
private SocketChannel socket;
public static final String CLIENT_VERSION = "Rs 0.09";
TabLayout.Tab secondTab;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// get the reference of FrameLayout and TabLayout
simpleFrameLayout = (FrameLayout) findViewById(R.id.simpleFrameLayout);
tabLayout = (TabLayout) findViewById(R.id.simpleTabLayout);
// Create a new Tab named "First"
TabLayout.Tab firstTab = tabLayout.newTab();
firstTab.setText("First"); // set the Text for the first Tab
// first tab
tabLayout.addTab(firstTab); // add the tab at in the TabLayout
// Create a new Tab named "Second"
secondTab = tabLayout.newTab();
secondTab.setText("Second"); // set the Text for the second Tab
tabLayout.addTab(secondTab); // add the tab in the TabLayout
FragmentManager fm = getSupportFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
ft.add(R.id.simpleFrameLayout, f);
ft.add(R.id.simpleFrameLayout, s);
ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
ft.commit();
ft.hide(s);
tabLayout.setOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
@Override
public void onTabSelected(TabLayout.Tab tab) {
// get the current selected tab's position and replace the fragment accordingly
FragmentTransaction ft3 = getSupportFragmentManager().beginTransaction();
switch (tab.getPosition()) {
case 0:
if(f.isAdded()){
ft3.show(f);
ft3.commit();
if(s.isAdded()){ft3.hide(s);}
}
break;
case 1:
if(s.isAdded()){
ft3.show(s);
ft3.commit();
if(f.isAdded()){ft3.hide(f);}
}
break;
}
}
@Override
public void onTabUnselected(TabLayout.Tab tab) {
}
@Override
public void onTabReselected(TabLayout.Tab tab) {
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menuopciones, menu);
return true;
}
public void conectar(String nombre, String ip, int puerto) throws UnknownHostException{
SharedPreferences prefe=this.getApplicationContext().getSharedPreferences("datos", Context.MODE_PRIVATE);
HCUser usuario = new HCUser(prefe.getString("usuario",""), (short)0, HLineType.HLNone, HBrowsable.Not_Browsable, (byte)prefe.getInt("edad",0), getgender(prefe.getInt("sexo",-1)), contains(prefe.getInt("pais",-1)), prefe.getString("estado",""), Settings.LocalIP(), (short)Settings.Port(), Settings.LocalIP(), InetAddress.getByName("0.0.0.0"), (short)65535, (byte)0, (byte)0, (byte)0);
this.user = usuario;
this.reader = new Thread(this);
this.reader.setPriority(Thread.MAX_PRIORITY);
this.updateTimer = new Timer(new Runnable() {
public void run() {
}
}, 80000, false);
this.running = false;
try{
connect(InetAddress.getByName(ip),puerto, nombre);
}
catch(Exception e){
StringWriter sw = new StringWriter();
e.printStackTrace(new PrintWriter(sw));
String stacktrace = sw.toString();
// create an email intent to send to yourself
final Intent emailIntent = new Intent(android.content.Intent.ACTION_SEND);
emailIntent.setType("plain/text");
emailIntent.putExtra(android.content.Intent.EXTRA_EMAIL, new String[] { "lets.think.android@gmail.com" });
emailIntent.putExtra(android.content.Intent.EXTRA_SUBJECT, "App Error Report");
emailIntent.putExtra(android.content.Intent.EXTRA_TEXT, stacktrace);
// start the email activity - note you need to start it with a chooser
startActivity(Intent.createChooser(emailIntent, "Send error report..."));
}
}
public static HGender getgender(int num){
if(num==0){
return HGender.Unknow;
}
if(num==1){
return HGender.Male;
}
return HGender.Female;
}
public static HLocation contains(int test) {
if(test >= 47 && test < 87){
test = test + 1;
return HLocation.get((byte)test);
}
if(test >= 87 && test < 89){
test = test + 2;
return HLocation.get((byte)test);
}
test = test + 3;
return HLocation.get((byte)test);
}
public void connect(InetAddress ip, int port, String nombre) throws IOException {
InetSocketAddress addr = new InetSocketAddress(ip, port);
connect(addr, nombre);
}
public void connect(SocketAddress addr, String nombre) throws IOException {
try {
socket = SocketChannel.open();
socket.socket().connect(addr, 1000);
TabLayout.Tab tab = tabLayout.getTabAt(1);
tab.select();
s.room.setText(nombre);
socket.configureBlocking(true);
while (!socket.finishConnect()) {
}
running = true;
if (!reader.isAlive()) {
reader.start();
}
P2 pkg = new P2(user.getGuid(), (short) user.getFilecount(), (short) user.getDataport(), user.getNodeIp(), (short) user.getNodePort(), user.getLinetype(), user.getUsername(), CLIENT_VERSION, user.getPrivateIp(), user.getPublicIp(), user.getBrowsable(), user.getUploads(), user.getMaxUploads(), user.getQueued(), user.getAge(), user.getGender(), user.getCountry(), user.getRegion());
send(pkg);
updateTimer.startTimer();
}
catch(SocketTimeoutException ex)
{
}
}
public void send(HPackage pkg) {
try {
socket.write(HPackageSerializer.getInstance().getBytes(pkg));
} catch (IOException ex) {
System.err.println(ex.getMessage());
}
}
@Override
public void run() {
}
}
我想启动方法conectar()。但是使用 AsynTask 会很糟糕，因为我必须将所有方法放在另一个 class 中，并且会发生冲突。它不会工作，我想......我怎么能这样做？谢谢
如果您需要在后台做一个简单的工作，请不要使用已弃用的 AsyncTask 使用 Executors。
Executor executor = Executors.newSingleThreadExecutor();
executor.execute(new Runnable() {
@Override
public void run() {
// run your background code here
}
});
这种情况下如何正确使用Asynctask？ 所以在某些应用程序中我遇到了异常：“android.os.NetworkOnMainThreadException”
解决它的一种方法是使用 Asynctask
但是在这种情况下如何使用它呢？
package com.mycompany.myapp;
import android.app.*;
import android.os.*;
import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v7.app.AppCompatActivity;
import android.widget.FrameLayout;
import java.io.*;
import java.net.*;
import android.content.Intent;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.EditText;
import android.widget.Toast;
import android.view.View;
import android.text.Html;
import java.util.Scanner;
import com.mycompany.myapp.client.HCUser;
import com.mycompany.myapp.common.*;
import android.content.SharedPreferences;
import android.content.Context;
import com.mycompany.myapp.common.constants.*;
import java.util.ArrayList;
import Misc.Settings;
import com.mycompany.myapp.client.*;
import java.nio.channels.SocketChannel;
import com.mycompany.myapp.client.packages.tcp.P2;
import com.mycompany.myapp.common.packages.tcp.HPackage;
import com.mycompany.myapp.common.serialization.HPackageSerializer;
public class MainActivity extends AppCompatActivity implements Runnable
{
FrameLayout simpleFrameLayout;
TabLayout tabLayout;
static Socket sock = new Socket();
static OutputStream out = null;
static DataInputStream dIn;
FirstFragment f = new FirstFragment();
SecondFragment s = new SecondFragment();
private HCUser user;
private Thread reader;
private Timer updateTimer;
private boolean running;
private SocketChannel socket;
public static final String CLIENT_VERSION = "Rs 0.09";
TabLayout.Tab secondTab;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// get the reference of FrameLayout and TabLayout
simpleFrameLayout = (FrameLayout) findViewById(R.id.simpleFrameLayout);
tabLayout = (TabLayout) findViewById(R.id.simpleTabLayout);
// Create a new Tab named "First"
TabLayout.Tab firstTab = tabLayout.newTab();
firstTab.setText("First"); // set the Text for the first Tab
// first tab
tabLayout.addTab(firstTab); // add the tab at in the TabLayout
// Create a new Tab named "Second"
secondTab = tabLayout.newTab();
secondTab.setText("Second"); // set the Text for the second Tab
tabLayout.addTab(secondTab); // add the tab in the TabLayout
FragmentManager fm = getSupportFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
ft.add(R.id.simpleFrameLayout, f);
ft.add(R.id.simpleFrameLayout, s);
ft.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_OPEN);
ft.commit();
ft.hide(s);
tabLayout.setOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
@Override
public void onTabSelected(TabLayout.Tab tab) {
// get the current selected tab's position and replace the fragment accordingly
FragmentTransaction ft3 = getSupportFragmentManager().beginTransaction();
switch (tab.getPosition()) {
case 0:
if(f.isAdded()){
ft3.show(f);
ft3.commit();
if(s.isAdded()){ft3.hide(s);}
}
break;
case 1:
if(s.isAdded()){
ft3.show(s);
ft3.commit();
if(f.isAdded()){ft3.hide(f);}
}
break;
}
}
@Override
public void onTabUnselected(TabLayout.Tab tab) {
}
@Override
public void onTabReselected(TabLayout.Tab tab) {
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menuopciones, menu);
return true;
}
public void conectar(String nombre, String ip, int puerto) throws UnknownHostException{
SharedPreferences prefe=this.getApplicationContext().getSharedPreferences("datos", Context.MODE_PRIVATE);
HCUser usuario = new HCUser(prefe.getString("usuario",""), (short)0, HLineType.HLNone, HBrowsable.Not_Browsable, (byte)prefe.getInt("edad",0), getgender(prefe.getInt("sexo",-1)), contains(prefe.getInt("pais",-1)), prefe.getString("estado",""), Settings.LocalIP(), (short)Settings.Port(), Settings.LocalIP(), InetAddress.getByName("0.0.0.0"), (short)65535, (byte)0, (byte)0, (byte)0);
this.user = usuario;
this.reader = new Thread(this);
this.reader.setPriority(Thread.MAX_PRIORITY);
this.updateTimer = new Timer(new Runnable() {
public void run() {
}
}, 80000, false);
this.running = false;
try{
connect(InetAddress.getByName(ip),puerto, nombre);
}
catch(Exception e){
StringWriter sw = new StringWriter();
e.printStackTrace(new PrintWriter(sw));
String stacktrace = sw.toString();
// create an email intent to send to yourself
final Intent emailIntent = new Intent(android.content.Intent.ACTION_SEND);
emailIntent.setType("plain/text");
emailIntent.putExtra(android.content.Intent.EXTRA_EMAIL, new String[] { "lets.think.android@gmail.com" });
emailIntent.putExtra(android.content.Intent.EXTRA_SUBJECT, "App Error Report");
emailIntent.putExtra(android.content.Intent.EXTRA_TEXT, stacktrace);
// start the email activity - note you need to start it with a chooser
startActivity(Intent.createChooser(emailIntent, "Send error report..."));
}
}
public static HGender getgender(int num){
if(num==0){
return HGender.Unknow;
}
if(num==1){
return HGender.Male;
}
return HGender.Female;
}
public static HLocation contains(int test) {
if(test >= 47 && test < 87){
test = test + 1;
return HLocation.get((byte)test);
}
if(test >= 87 && test < 89){
test = test + 2;
return HLocation.get((byte)test);
}
test = test + 3;
return HLocation.get((byte)test);
}
public void connect(InetAddress ip, int port, String nombre) throws IOException {
InetSocketAddress addr = new InetSocketAddress(ip, port);
connect(addr, nombre);
}
public void connect(SocketAddress addr, String nombre) throws IOException {
try {
socket = SocketChannel.open();
socket.socket().connect(addr, 1000);
TabLayout.Tab tab = tabLayout.getTabAt(1);
tab.select();
s.room.setText(nombre);
socket.configureBlocking(true);
while (!socket.finishConnect()) {
}
running = true;
if (!reader.isAlive()) {
reader.start();
}
P2 pkg = new P2(user.getGuid(), (short) user.getFilecount(), (short) user.getDataport(), user.getNodeIp(), (short) user.getNodePort(), user.getLinetype(), user.getUsername(), CLIENT_VERSION, user.getPrivateIp(), user.getPublicIp(), user.getBrowsable(), user.getUploads(), user.getMaxUploads(), user.getQueued(), user.getAge(), user.getGender(), user.getCountry(), user.getRegion());
send(pkg);
updateTimer.startTimer();
}
catch(SocketTimeoutException ex)
{
}
}
public void send(HPackage pkg) {
try {
socket.write(HPackageSerializer.getInstance().getBytes(pkg));
} catch (IOException ex) {
System.err.println(ex.getMessage());
}
}
@Override
public void run() {
}
}
我想启动方法conectar()。但是使用 AsynTask 会很糟糕，因为我必须将所有方法放在另一个 class 中，并且会发生冲突。它不会工作，我想......我怎么能这样做？谢谢
如果您需要在后台做一个简单的工作，请不要使用已弃用的 AsyncTask 使用 Executors。
Executor executor = Executors.newSingleThreadExecutor();
executor.execute(new Runnable() {
@Override
public void run() {
// run your background code here
}
});