-Improved email sanity verifications when adding emails when creating a new Key

-fixed a few NFC crashes
-fixed a few instances when showing the keyboard would crash the Activity
-fixed a case where adding new emails would crash the app if the user went back and forth between the Add Email fragment and the Add Name fragment.

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/CreateKeyEmailFragment.java

@@ -18,7 +18,6 @@
 package org.sufficientlysecure.keychain.ui;
 
 import android.app.Activity;
-import android.content.Context;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.Message;
@@ -27,6 +26,7 @@ import android.support.v4.app.Fragment;
 import android.support.v7.widget.DefaultItemAnimator;
 import android.support.v7.widget.LinearLayoutManager;
 import android.support.v7.widget.RecyclerView;
+import android.util.Patterns;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
@@ -44,6 +44,7 @@ import org.sufficientlysecure.keychain.ui.widget.EmailEditText;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.regex.Pattern;
 
 public class CreateKeyEmailFragment extends Fragment {
 
@@ -73,14 +74,13 @@ public class CreateKeyEmailFragment extends Fragment {
      * Checks if text of given EditText is not empty. If it is empty an error is
      * set and the EditText gets the focus.
      *
-     * @param context
      * @param editText
      * @return true if EditText is not empty
      */
-    private static boolean isEditTextNotEmpty(Context context, EditText editText) {
+    private boolean isMainEmailValid(EditText editText) {
         boolean output = true;
-        if (editText.getText().length() == 0) {
+        if (!checkEmail(editText.getText().toString(), false)) {
-            editText.setError(context.getString(R.string.create_key_empty));
+            editText.setError(getString(R.string.create_key_empty));
             editText.requestFocus();
             output = false;
         } else {
@@ -125,7 +125,7 @@ public class CreateKeyEmailFragment extends Fragment {
         // initial values
         if (mAdditionalEmailModels == null) {
             mAdditionalEmailModels = new ArrayList<>();
-            if (mCreateKeyActivity.mAdditionalEmails != null) {
+            if (mCreateKeyActivity.mAdditionalEmails != null && mEmailAdapter != null) {
                 mEmailAdapter.addAll(mCreateKeyActivity.mAdditionalEmails);
             }
         }
@@ -144,6 +144,65 @@ public class CreateKeyEmailFragment extends Fragment {
         return view;
     }
 
+    /**
+     * Checks if a given email is valid
+     *
+     * @param email
+     * @param additionalEmail
+     * @return
+     */
+    private boolean checkEmail(String email, boolean additionalEmail) {
+        //check for email format or if the user did any input
+        if (!isEmailFormatValid(email)) {
+            Notify.create(getActivity(),
+                    getString(R.string.create_key_email_invalid_email),
+                    Notify.LENGTH_LONG, Notify.Style.ERROR).show();
+            return false;
+        }
+
+        //check for duplicated emails
+        if (!additionalEmail && isEmailDuplicatedInsideAdapter(email) || additionalEmail &&
+                mEmailEdit.getText().length() > 0 && email.equals(mEmailEdit.getText().toString())) {
+            Notify.create(getActivity(),
+                    getString(R.string.create_key_email_already_exists_text),
+                    Notify.LENGTH_LONG, Notify.Style.ERROR).show();
+            return false;
+        }
+
+        return true;
+    }
+
+    /**
+     * Checks the email format
+     * Uses the default Android Email Pattern
+     *
+     * @param email
+     * @return
+     */
+    private boolean isEmailFormatValid(String email) {
+        Pattern emailPattern = Patterns.EMAIL_ADDRESS;
+
+        //check for email format or if the user did any input
+        return !(email.length() == 0 || !emailPattern.matcher(email).matches());
+    }
+
+    /**
+     * Checks for duplicated emails inside the additional email adapter.
+     *
+     * @param email
+     * @return
+     */
+    private boolean isEmailDuplicatedInsideAdapter(String email) {
+        //check for duplicated emails inside the adapter
+        for (EmailAdapter.ViewModel model : mAdditionalEmailModels) {
+            if (email.equals(model.email)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
     private void addEmail() {
         Handler returnHandler = new Handler() {
             @Override
@@ -152,26 +211,10 @@ public class CreateKeyEmailFragment extends Fragment {
                     Bundle data = message.getData();
 
                     String email = data.getString(AddEmailDialogFragment.MESSAGE_DATA_EMAIL);
-
+                    if (checkEmail(email, true)) {
-                    if (email.length() > 0 && mEmailEdit.getText().length() > 0 &&
+                        // add new user id
-                            email.equals(mEmailEdit.getText().toString())) {
+                        mEmailAdapter.add(email);
-                        Notify.create(getActivity(),
-                                getString(R.string.create_key_email_already_exists_text),
-                                Notify.LENGTH_LONG, Notify.Style.ERROR).show();
-                        return;
                     }
-                    //check for duplicated emails inside the adapter
-                    for (EmailAdapter.ViewModel model : mAdditionalEmailModels) {
-                        if (email.equals(model.email)) {
-                            Notify.create(getActivity(),
-                                    getString(R.string.create_key_email_already_exists_text),
-                                    Notify.LENGTH_LONG, Notify.Style.ERROR).show();
-                            return;
-                        }
-                    }
-
-                    // add new user id
-                    mEmailAdapter.add(email);
                 }
             }
         };
@@ -191,7 +234,7 @@ public class CreateKeyEmailFragment extends Fragment {
     }
 
     private void nextClicked() {
-        if (isEditTextNotEmpty(getActivity(), mEmailEdit)) {
+        if (isMainEmailValid(mEmailEdit)) {
             // save state
             mCreateKeyActivity.mEmail = mEmailEdit.getText().toString();
             mCreateKeyActivity.mAdditionalEmails = getAdditionalEmails();

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/base/BaseNfcActivity.java

@@ -451,6 +451,8 @@ public abstract class BaseNfcActivity extends BaseActivity {
      */
     public void enableNfcForegroundDispatch() {
         mNfcAdapter = NfcAdapter.getDefaultAdapter(this);
+        if(mNfcAdapter == null) return;
+
         Intent nfcI = new Intent(this, getClass())
                 .addFlags(Intent.FLAG_ACTIVITY_SINGLE_TOP | Intent.FLAG_ACTIVITY_CLEAR_TOP);
         PendingIntent nfcPendingIntent = PendingIntent.getActivity(this, 0, nfcI, PendingIntent.FLAG_CANCEL_CURRENT);
@@ -472,7 +474,9 @@ public abstract class BaseNfcActivity extends BaseActivity {
      * Disable foreground dispatch in onPause!
      */
     public void disableNfcForegroundDispatch() {
-        mNfcAdapter.disableForegroundDispatch(this);
+        if(mNfcAdapter != null) {
+            mNfcAdapter.disableForegroundDispatch(this);
+        }
         Log.d(Constants.TAG, "NfcForegroundDispatch has been disabled!");
     }
 

OpenKeychain/src/main/java/org/sufficientlysecure/keychain/ui/dialog/AddEmailDialogFragment.java

@@ -112,9 +112,11 @@ public class AddEmailDialogFragment extends DialogFragment implements OnEditorAc
                 mEmail.post(new Runnable() {
                     @Override
                     public void run() {
-                        InputMethodManager imm = (InputMethodManager) getActivity()
+                        if(getActivity() != null) {
-                                .getSystemService(Context.INPUT_METHOD_SERVICE);
+                            InputMethodManager imm = (InputMethodManager) getActivity()
-                        imm.showSoftInput(mEmail, InputMethodManager.SHOW_IMPLICIT);
+                                    .getSystemService(Context.INPUT_METHOD_SERVICE);
+                            imm.showSoftInput(mEmail, InputMethodManager.SHOW_IMPLICIT);
+                        }
                     }
                 });
             }

OpenKeychain/src/main/res/layout/add_email_dialog.xml

@@ -21,6 +21,7 @@
         android:layout_marginTop="16dp"
         android:hint="@string/label_email"
         android:imeOptions="actionNext"
+        android:inputType="textEmailAddress"
         android:textAppearance="?android:attr/textAppearanceMedium" />
 
 </LinearLayout>

OpenKeychain/src/main/res/layout/create_key_email_fragment.xml

@@ -32,6 +32,7 @@
                 android:layout_marginTop="16dp"
                 android:layout_marginBottom="8dp"
                 android:imeOptions="actionNext"
+                android:inputType="textEmailAddress"
                 android:hint="@string/label_email"
                 android:ems="10" />
 

OpenKeychain/src/main/res/values/strings.xml

@@ -631,6 +631,7 @@
     <string name="create_key_add_email">"Add email address"</string>
     <string name="create_key_add_email_text">"Additional email addresses are also associated to this key and can be used for secure communication."</string>
     <string name="create_key_email_already_exists_text">"Email address has already been added"</string>
+    <string name="create_key_email_invalid_email">"Email address format is invalid"</string>
 
     <!-- View key -->
     <string name="view_key_revoked">"Revoked: Key must not be used anymore!"</string>