我有一个活动(MainActivity)，它有一个内部的AsyncTask类。此类获取本地无线配置，例如：IP 地址、子网、网关等。我有一个获取外部 ip 配置的外部异步任务。与IP地址，主机名，位置等一样，第二类为此使用JSON REST API。但是当我从二等舱发布到列表视图时，我无法。我不知道这是否可能。我将当前上下文传递给二类，并在主活动终止时使用弱引用。另外，我正在为列表视图使用自定义阵列适配器。据我所知，doinbackground() 方法在不同的线程中运行，因此这两个类之间的同步是如何发生的。我正在考虑的另一种解决方案不是从第二个类直接发布到 listview 中，而是存储在主类上的变量中，然后从第一个异步任务输出到 listview。但这会产生意想不到的结果。这是怎么做到的。以前有人做过类似的事情吗？谢谢注意：我从主活动中重新导入了一些内容，否则类将在这里占用太多空间。 主要活动
package org.techgeorge.netxcan;
import org.apache.commons.net.util.SubnetUtils;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
import utils.IpUtils;
public class MainActivity extends AppCompatActivity {
private ListView listView;
private ArrayList<String> wifiIface;
private WifiAdapter wifiAdapter;
private String TAG = this.getClass().getName();
private String extIpv6;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
wifiIface = new ArrayList<>();
listView = (ListView) findViewById(R.id.output_list);
wifiAdapter = new WifiAdapter(this, R.layout.list_item, wifiIface);
listView.setAdapter(wifiAdapter);
WifiAsyncTask wifiTask = new WifiAsyncTask(this);
wifiTask.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
getWanIpInfo();
FloatingActionButton fab = findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
}
});
}
@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);
}
public void setExtIpv6(String ipv6) {
this.extIpv6 = ipv6;
}
public ArrayList<String> getWifiIface() {
return wifiIface;
}
public ArrayAdapter<String> getArrayAdapter() {
return wifiAdapter;
}
public void getWanIpInfo() {
WanIpTask wanIpTask = new WanIpTask(this);
wanIpTask.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR);
}
public class WifiAsyncTask extends AsyncTask<Void, Void, Void> {
WeakReference<MainActivity> weakReference;
private static final String WEB_IP_SERVICE = "https://ipinfo.io/json";
String error = "Couldn't get external IP";
int subnet;
Wireless wifi;
public WifiAsyncTask(MainActivity activity) {
weakReference = new WeakReference<>(activity);
}
@Override
protected void onPreExecute() {
wifi = new Wireless(getApplicationContext());
wifi.getInternalMobileIpAddress();
}
@Override
protected Void doInBackground(Void... params) {
try {
if ( wifi.getNetworkInfo() != null && wifi.getNetworkInfo().isConnected()) {
adding Lan stuff
subnet = wifi.getInternalWifiSubnet();
wifiIface.add("LAN Information");
wifiIface.add("Ipv6 "+wifi.getIpv6());
wifiIface.add("Mac "+wifi.getMacAddress());
wifiIface.add("Ipv4 "+wifi.getWifiInetAddress().getHostAddress()+"/"+subnet);
wifiIface.add("Host "+wifi.getWifiInetAddress().getHostName());
wifiIface.add("Dns1 "+IpUtils.getIpToString(wifi.getDhcpInfo().dns1));
wifiIface.add("Dns2 "+IpUtils.getIpToString(wifi.getDhcpInfo().dns2));
wifiIface.add("Gateway "+IpUtils.getIpToString(wifi.getDhcpInfo().gateway));
//adding wireless stuff
wifiIface.add("WIFI Information");
wifiIface.add("SSID "+wifi.getSSID());
wifiIface.add("Speed "+wifi.getLinkSpeed()+ "Mbs");
wifiIface.add("Signal "+wifi.getWifiInfo().getRssi() + "db");
wifiIface.add("Channel "+wifi.getWifiInfo().getNetworkId() + "");
}
}
} catch (Wireless.NoConnectivityManagerException e) {
e.printStackTrace();
} catch (Wireless.NoWifiManagerException e) {
e.printStackTrace();
} catch (SocketException e) {
e.printStackTrace();
} catch (Wireless.NoWifiInterface noWifiInterface) {
noWifiInterface.printStackTrace();
} catch (UnknownHostException e) {
e.printStackTrace();
}
return null;
}
@Override
protected void onProgressUpdate(Void... values) {
wifiAdapter.notifyDataSetChanged();
}
@Override
protected void onPostExecute(Void... values) {
MainActivity activity = weakReference.get();
if(activity != null || !activity.isFinishing()) {
wifiAdapter.notifyDataSetChanged();
}
}
}
}
万阿辛任务
package org.techgeorge.netxcan;
import android.annotation.SuppressLint;
import android.os.AsyncTask;
import android.util.Log;
import java.io.DataInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.lang.ref.WeakReference;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
public class WanIpTask extends AsyncTask<Void, Void, String> {
// IP service is 100% open source https://github.com/aaronjwood/public-ip-api
// private static final String EXTERNAL_IP_SERVICE = "https://public-ip-api.appspot.com/";
private static final String EXTERNAL_IP_SERVICE = "https://ipinfo.io/json";
private final WeakReference<MainActivity> delegate;
/**
* Constructor to set the delegate
*
* @param delegate Called when the external IP has been fetched
*/
public WanIpTask(MainActivity delegate) {
this.delegate = new WeakReference<>(delegate);
}
/**
* Fetch the external IP address
*
* @param params
* @return External IP address
*/
@Override
@SuppressLint("NewApi")
protected String doInBackground(Void... params) {
String error = "Couldn't get external IP";
OkHttpClient httpClient = new OkHttpClient();
Request request = new Request.Builder().url(EXTERNAL_IP_SERVICE).build();
try (Response response = httpClient.newCall(request).execute()) {
if (!response.isSuccessful()) {
return error;
}
return response.body().string().trim();
} catch (IOException e) {
return error;
}
}
/**
* Calls the delegate when the external IP has been fetched
*
* @param result External IP address
*/
@Override
protected void onPostExecute(String result) {
MainActivity activity = delegate.get();
if (activity != null) {
activity.getWifiIface().add(result);
String[] wanResult = result.split("n");
for(int i = 0; i < wanResult.length; i++) {
activity.getWifiIface.add()
}
}
}
}
在 WanAsynTask 中，您不会不更新适配器
@Override
protected void onPostExecute(String result) {
MainActivity activity = delegate.get();
if (activity != null) {
activity.getWifiIface().add(result);
String[] wanResult = result.split("n");
for(int i = 0; i < wanResult.length; i++) {
activity.getWifiIface.add()
}
// notify adapter
activity.wifiAdapter.notifyDataSetChanged();
}
}