Currently, I have a login code, which will post data to a PHP script and read the data output by the script (JSON encoded) to determine if the login credentials are correct.
The following is part of my LoginActivity.java, called when the login button is clicked:
public void login(View view) {
String usernameValue = username.getText().toString(),
passwordValue = password.getText().toString(),
orgValue = org.getText().toString();
if (orgValue.matches("")) {
snackbar.make(view, "Organisation cannot be blank", Snackbar.LENGTH_LONG).show();
} else if (usernameValue.matches("")) {
snackbar.make(view, "Username cannot be blank", Snackbar.LENGTH_LONG).show();
} else if (passwordValue.matches("")) {
snackbar.make(view, "Password cannot be blank", Snackbar.LENGTH_LONG).show();
} else {
/**
* Login code goes here.
* This is where the error seems to be at.
*/
URL url;
String data;
try {
url = new URL("http://myurl.com/verify/users.php");
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setReadTimeout(15000);
connection.setConnectTimeout(15000);
connection.setRequestMethod("POST");
connection.setDoInput(true);
connection.setDoOutput(true);
data = URLEncoder.encode("username", "UTF-8") + "=" + URLEncoder.encode(usernameValue, "UTF-8") +
"&" + URLEncoder.encode("password", "UTF-8") + "=" + URLEncoder.encode(passwordValue, "UTF-8") +
"&" + URLEncoder.encode("org", "UTF-8") + "=" + URLEncoder.encode(orgValue, "UTF-8");
OutputStream outputStream = connection.getOutputStream();
BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(outputStream, "UTF-8"));
writer.write(data);
writer.flush();
writer.close();
outputStream.close();
int responseCode = connection.getResponseCode();
if (responseCode == HttpURLConnection.HTTP_OK) {
JsonReader reader = new JsonReader(new InputStreamReader(connection.getInputStream()));
int success = -1;
String message = null;
reader.beginArray();
while (reader.hasNext()) {
reader.beginObject();
while (reader.hasNext()) {
String name = reader.nextName();
switch (name) {
case "success":
success = reader.nextInt();
break;
case "error_message":
message = reader.nextString();
break;
default:
reader.skipValue();
break;
}
}
reader.endObject();
}
reader.endArray();
reader.close();
if (success == 1) {
snackbar.make(view, "You are successfully logged in as " + usernameValue + "!", Snackbar.LENGTH_LONG).show();
}
else {
snackbar.make(view, "Error: " + message, Snackbar.LENGTH_LONG).show();
}
}
else {
snackbar.make(view, "Error " + responseCode + " encountered. Please try again later.", Snackbar.LENGTH_LONG).show();
}
} catch (IOException e) {
throw new RuntimeException(e);
}
}
}
However, when I click the login button, the app crashed with the following message in the logcat:
04-24 16:55:24.251 16674-16674/com.example.android.loginexample E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.android.loginexample, PID: 16674
java.lang.IllegalStateException: Could not execute method for android:onClick
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:293)
at android.view.View.performClick(View.java:5242)
at android.widget.TextView.performClick(TextView.java:10530)
at android.view.View$PerformClick.run(View.java:21185)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6872)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1404)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1199)
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:288)
at android.view.View.performClick(View.java:5242)
at android.widget.TextView.performClick(TextView.java:10530)
at android.view.View$PerformClick.run(View.java:21185)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6872)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1404)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1199)
Caused by: android.os.NetworkOnMainThreadException
at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1147)
at java.net.InetAddress.lookupHostByName(InetAddress.java:418)
at java.net.InetAddress.getAllByNameImpl(InetAddress.java:252)
at java.net.InetAddress.getAllByName(InetAddress.java:215)
at com.android.okhttp.HostResolver$1.getAllByName(HostResolver.java:29)
at com.android.okhttp.internal.http.RouteSelector.resetNextInetSocketAddress(RouteSelector.java:232)
at com.android.okhttp.internal.http.RouteSelector.next(RouteSelector.java:124)
at com.android.okhttp.internal.http.HttpEngine.connect(HttpEngine.java:370)
at com.android.okhttp.internal.http.HttpEngine.sendRequest(HttpEngine.java:298)
at com.android.okhttp.internal.http.HttpURLConnectionImpl.execute(HttpURLConnectionImpl.java:399)
at com.android.okhttp.internal.http.HttpURLConnectionImpl.connect(HttpURLConnectionImpl.java:110)
at com.android.okhttp.internal.http.HttpURLConnectionImpl.getOutputStream(HttpURLConnectionImpl.java:221)
at com.example.android.loginexample.LoginActivity.login(LoginActivity.java:68)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:288)
at android.view.View.performClick(View.java:5242)
at android.widget.TextView.performClick(TextView.java:10530)
at android.view.View$PerformClick.run(View.java:21185)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:145)
at android.app.ActivityThread.main(ActivityThread.java:6872)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1404)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1199)
Any help will be appreciated! Thanks in advance :)
