Added copy button to device IDs (fixes #559).

src/main/java/com/nutomic/syncthingandroid/fragments/DeviceFragment.java

@@ -3,8 +3,10 @@ package com.nutomic.syncthingandroid.fragments;
 import android.app.Fragment;
 import android.content.DialogInterface;
 import android.content.Intent;
+import android.graphics.drawable.Drawable;
 import android.os.Bundle;
 import android.support.annotation.Nullable;
+import android.support.v4.content.ContextCompat;
 import android.support.v7.app.AlertDialog;
 import android.support.v7.widget.SwitchCompat;
 import android.text.Editable;
@@ -378,6 +380,8 @@ public class DeviceFragment extends Fragment implements
     private void prepareEditMode() {
         getActivity().getWindow().setSoftInputMode(SOFT_INPUT_STATE_ALWAYS_HIDDEN);
 
+        Drawable dr = ContextCompat.getDrawable(getActivity(), R.drawable.ic_content_copy_black_24dp);
+        mIdView.setCompoundDrawablesWithIntrinsicBounds(null, null, dr, null);
         mIdView.setEnabled(false);
         mQrButton.setVisibility(GONE);
 

src/main/java/com/nutomic/syncthingandroid/fragments/DrawerFragment.java

@@ -154,7 +154,6 @@ public class DrawerFragment extends Fragment implements RestApi.OnReceiveSystemI
             return;
 
         mDeviceId.setText(info.myID);
-        mDeviceId.setVisibility(View.VISIBLE);
         mDeviceId.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {

src/main/res/layout/fragment_drawer.xml

@@ -61,7 +61,8 @@
                     android:layout_height="wrap_content"
                     android:fontFamily="monospace"
                     android:textAppearance="@style/TextAppearance.AppCompat.Caption"
-                    android:visibility="invisible" />
+                    android:drawableRight="@drawable/ic_content_copy_black_24dp"
+                    android:drawableEnd="@drawable/ic_content_copy_black_24dp" />
             </LinearLayout>
 
             <View