Android-Java-NetworkOnMainThreadException

每当我试图发送一个数据包时，我都会收到一个非法的状态异常，但我不知道为什么会发生。据我所知，每个变量都被初始化，这通常是导致非法状态异常的原因

以下是错误：

W/myApp: Reached Function
D/libc-netbsd: [getaddrinfo]: hostname=xxxxx; servname=(null); cache_mode=(null), netid=0; mark=0
D/libc: getaddrinfo called from pid =1013
D/libc-netbsd: [getaddrinfo]: ai_addrlen=0; ai_canonname=xxxxx; ai_flags=4; ai_family=0
W/myApp: 1 converted to bytes
W/myApp: Packet created: Send to: 144.118.119.31 Send: [B@30365bc6 1 1
D/AndroidRuntime: Shutting down VM
E/AndroidRuntime: FATAL EXCEPTION: main
E/AndroidRuntime: Process: com.example.cody.lighttest, PID: 1013
E/AndroidRuntime: java.lang.IllegalStateException: Could not execute method of the activity
E/AndroidRuntime:     at android.view.View$1.onClick(View.java:4015)
E/AndroidRuntime:     at android.view.View.performClick(View.java:4764)
E/AndroidRuntime:     at android.view.View$PerformClick.run(View.java:19844)
E/AndroidRuntime:     at android.os.Handler.handleCallback(Handler.java:739)
E/AndroidRuntime:     at android.os.Handler.dispatchMessage(Handler.java:95)
E/AndroidRuntime:     at android.os.Looper.loop(Looper.java:135)
E/AndroidRuntime:     at android.app.ActivityThread.main(ActivityThread.java:5351)
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Native Method)
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Method.java:372)
E/AndroidRuntime:     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:908)
E/AndroidRuntime:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:703)
E/AndroidRuntime:  Caused by: java.lang.reflect.InvocationTargetException
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Native Method)
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Method.java:372)
E/AndroidRuntime:     at android.view.View$1.onClick(View.java:4010)
E/AndroidRuntime:     at android.view.View.performClick(View.java:4764) 
E/AndroidRuntime:     at android.view.View$PerformClick.run(View.java:19844) 
E/AndroidRuntime:     at android.os.Handler.handleCallback(Handler.java:739) 
E/AndroidRuntime:     at android.os.Handler.dispatchMessage(Handler.java:95) 
E/AndroidRuntime:     at android.os.Looper.loop(Looper.java:135) 
E/AndroidRuntime:     at android.app.ActivityThread.main(ActivityThread.java:5351) 
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Native Method) 
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Method.java:372) 
E/AndroidRuntime:     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:908) 
E/AndroidRuntime:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:703) 
E/AndroidRuntime:  Caused by: android.os.NetworkOnMainThreadException
E/AndroidRuntime:     at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1147)
E/AndroidRuntime:     at libcore.io.BlockGuardOs.sendto(BlockGuardOs.java:276)
E/AndroidRuntime:     at libcore.io.IoBridge.sendto(IoBridge.java:513)
E/AndroidRuntime:     at java.net.PlainDatagramSocketImpl.send(PlainDatagramSocketImpl.java:184)
E/AndroidRuntime:     at java.net.DatagramSocket.send(DatagramSocket.java:305)
E/AndroidRuntime:     at com.example.cody.lighttest.MainActivity.sendMessage(MainActivity.java:72)
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Native Method) 
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Method.java:372) 
E/AndroidRuntime:     at android.view.View$1.onClick(View.java:4010) 
E/AndroidRuntime:     at android.view.View.performClick(View.java:4764) 
E/AndroidRuntime:     at android.view.View$PerformClick.run(View.java:19844) 
E/AndroidRuntime:     at android.os.Handler.handleCallback(Handler.java:739) 
E/AndroidRuntime:     at android.os.Handler.dispatchMessage(Handler.java:95) 
E/AndroidRuntime:     at android.os.Looper.loop(Looper.java:135) 
E/AndroidRuntime:     at android.app.ActivityThread.main(ActivityThread.java:5351) 
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Native Method) 
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Method.java:372) 
E/AndroidRuntime:     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:908) 
11-30 16:00:49.259 1013-1013/com.example.cody.lighttest E/AndroidRuntime:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:703) 
11-30 16:00:51.649 1013-1013/? I/Process: Sending signal. PID: 1013 SIG: 9

 public void sendMessage(View view) {
        // Send UDP message to server
        Log.w("myApp", "Reached Function");
        try {
            InetAddress IPAddress =  InetAddress.getByName("144.118.119.31");
            String toSend = "1";
            byte [] buf = toSend.getBytes();
            Log.w("myApp", "1 converted to bytes");
            DatagramPacket packet = new DatagramPacket(buf, toSend.length(), IPAddress, 5005);
            Log.w("myApp", "Packet created: Send to: " + IPAddress.getHostAddress() + " Send: " + buf.toString() + " " + buf.length + " " + toSend.length());
            DatagramSocket csock = new DatagramSocket(5005);
            csock.send(packet);
            Log.w("myApp", "Sent Packet");

    } catch (SocketException e) {
        e.printStackTrace();
    } catch (UnknownHostException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

下面是导致错误的代码：

W/myApp: Reached Function
D/libc-netbsd: [getaddrinfo]: hostname=xxxxx; servname=(null); cache_mode=(null), netid=0; mark=0
D/libc: getaddrinfo called from pid =1013
D/libc-netbsd: [getaddrinfo]: ai_addrlen=0; ai_canonname=xxxxx; ai_flags=4; ai_family=0
W/myApp: 1 converted to bytes
W/myApp: Packet created: Send to: 144.118.119.31 Send: [B@30365bc6 1 1
D/AndroidRuntime: Shutting down VM
E/AndroidRuntime: FATAL EXCEPTION: main
E/AndroidRuntime: Process: com.example.cody.lighttest, PID: 1013
E/AndroidRuntime: java.lang.IllegalStateException: Could not execute method of the activity
E/AndroidRuntime:     at android.view.View$1.onClick(View.java:4015)
E/AndroidRuntime:     at android.view.View.performClick(View.java:4764)
E/AndroidRuntime:     at android.view.View$PerformClick.run(View.java:19844)
E/AndroidRuntime:     at android.os.Handler.handleCallback(Handler.java:739)
E/AndroidRuntime:     at android.os.Handler.dispatchMessage(Handler.java:95)
E/AndroidRuntime:     at android.os.Looper.loop(Looper.java:135)
E/AndroidRuntime:     at android.app.ActivityThread.main(ActivityThread.java:5351)
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Native Method)
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Method.java:372)
E/AndroidRuntime:     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:908)
E/AndroidRuntime:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:703)
E/AndroidRuntime:  Caused by: java.lang.reflect.InvocationTargetException
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Native Method)
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Method.java:372)
E/AndroidRuntime:     at android.view.View$1.onClick(View.java:4010)
E/AndroidRuntime:     at android.view.View.performClick(View.java:4764) 
E/AndroidRuntime:     at android.view.View$PerformClick.run(View.java:19844) 
E/AndroidRuntime:     at android.os.Handler.handleCallback(Handler.java:739) 
E/AndroidRuntime:     at android.os.Handler.dispatchMessage(Handler.java:95) 
E/AndroidRuntime:     at android.os.Looper.loop(Looper.java:135) 
E/AndroidRuntime:     at android.app.ActivityThread.main(ActivityThread.java:5351) 
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Native Method) 
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Method.java:372) 
E/AndroidRuntime:     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:908) 
E/AndroidRuntime:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:703) 
E/AndroidRuntime:  Caused by: android.os.NetworkOnMainThreadException
E/AndroidRuntime:     at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1147)
E/AndroidRuntime:     at libcore.io.BlockGuardOs.sendto(BlockGuardOs.java:276)
E/AndroidRuntime:     at libcore.io.IoBridge.sendto(IoBridge.java:513)
E/AndroidRuntime:     at java.net.PlainDatagramSocketImpl.send(PlainDatagramSocketImpl.java:184)
E/AndroidRuntime:     at java.net.DatagramSocket.send(DatagramSocket.java:305)
E/AndroidRuntime:     at com.example.cody.lighttest.MainActivity.sendMessage(MainActivity.java:72)
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Native Method) 
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Method.java:372) 
E/AndroidRuntime:     at android.view.View$1.onClick(View.java:4010) 
E/AndroidRuntime:     at android.view.View.performClick(View.java:4764) 
E/AndroidRuntime:     at android.view.View$PerformClick.run(View.java:19844) 
E/AndroidRuntime:     at android.os.Handler.handleCallback(Handler.java:739) 
E/AndroidRuntime:     at android.os.Handler.dispatchMessage(Handler.java:95) 
E/AndroidRuntime:     at android.os.Looper.loop(Looper.java:135) 
E/AndroidRuntime:     at android.app.ActivityThread.main(ActivityThread.java:5351) 
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Native Method) 
E/AndroidRuntime:     at java.lang.reflect.Method.invoke(Method.java:372) 
E/AndroidRuntime:     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:908) 
11-30 16:00:49.259 1013-1013/com.example.cody.lighttest E/AndroidRuntime:     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:703) 
11-30 16:00:51.649 1013-1013/? I/Process: Sending signal. PID: 1013 SIG: 9

 public void sendMessage(View view) {
        // Send UDP message to server
        Log.w("myApp", "Reached Function");
        try {
            InetAddress IPAddress =  InetAddress.getByName("144.118.119.31");
            String toSend = "1";
            byte [] buf = toSend.getBytes();
            Log.w("myApp", "1 converted to bytes");
            DatagramPacket packet = new DatagramPacket(buf, toSend.length(), IPAddress, 5005);
            Log.w("myApp", "Packet created: Send to: " + IPAddress.getHostAddress() + " Send: " + buf.toString() + " " + buf.length + " " + toSend.length());
            DatagramSocket csock = new DatagramSocket(5005);
            csock.send(packet);
            Log.w("myApp", "Sent Packet");

    } catch (SocketException e) {
        e.printStackTrace();
    } catch (UnknownHostException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

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有没有关于问题是什么以及如何解决问题的线索？

您正在尝试在应用程序的主线程上执行网络操作。这是不允许的。看