Fix cursor movement, fixes #1024

Also fix a crash in case an action view is not shown and linkification
of the last link of a line.

opentasks/src/main/java/org/dmfs/tasks/linkify/ActionModeLinkify.java

@@ -70,24 +70,26 @@ public static void linkify(TextView textView, ActionModeListener listener)
         Matcher m = LINK_PATTERN.matcher(text);
         SpannableString s = new SpannableString(text);
         new ForEach<>(new Seq<>(s.getSpans(0, s.length(), ClickableSpan.class))).process(s::removeSpan);
-        while (m.find())
+        int pos = 0;
+        while (m.find(pos))
         {
             int start = m.start(1);
             int end = m.end(1);
+            pos = end;
             Uri uri = null;
             if (m.group(2) != null)
             {
                 uri = Uri.parse("tel:" + PhoneNumberUtils.normalizeNumber(m.group(2)));
             }
-            if (m.group(3) != null)
+            else if (m.group(3) != null)
             {
                 uri = Uri.parse(m.group(3));
                 if (uri.getScheme() == null)
                 {
                     uri = uri.buildUpon().scheme("https").build();
                 }
             }
-            if (m.group(4) != null)
+            else if (m.group(4) != null)
             {
                 uri = Uri.parse("mailto:" + m.group(4));
             }
@@ -158,7 +160,10 @@ public void onGetContentRect(ActionMode mode, View view, Rect outRect)
                                   };
 
                                   ActionMode am = textView.startActionMode(actionMode, android.view.ActionMode.TYPE_FLOATING);
-                                  closeActionTrigger.subscribe(am::finish);
+                                  if (am != null)
+                                  {
+                                      closeActionTrigger.subscribe(am::finish);
+                                  }
                               }
                           }
                       },

opentasks/src/main/java/org/dmfs/tasks/utils/DescriptionMovementMethod.java

@@ -0,0 +1,87 @@
+package org.dmfs.tasks.utils;
+
+import android.text.Layout;
+import android.text.Selection;
+import android.text.Spannable;
+import android.text.method.ArrowKeyMovementMethod;
+import android.text.method.MovementMethod;
+import android.text.style.ClickableSpan;
+import android.view.MotionEvent;
+import android.widget.TextView;
+
+
+/**
+ * A movement method which allows moving the cursor with the arrow keys while still providing clickable links.
+ * <p>
+ * TODO: provide a way to act on entering or leaving a Clickable span with the cursor.
+ */
+public class DescriptionMovementMethod extends ArrowKeyMovementMethod
+{
+    @Override
+    public boolean canSelectArbitrarily()
+    {
+        return true;
+    }
+
+
+    @Override
+    public boolean onTouchEvent(TextView widget, Spannable spannable, MotionEvent event)
+    {
+        int action = event.getAction();
+
+        if (action == MotionEvent.ACTION_UP || action == MotionEvent.ACTION_DOWN)
+        {
+            int x = (int) event.getX();
+            int y = (int) event.getY();
+
+            x -= widget.getTotalPaddingLeft();
+            y -= widget.getTotalPaddingTop();
+
+            x += widget.getScrollX();
+            y += widget.getScrollY();
+
+            Layout layout = widget.getLayout();
+            int line = layout.getLineForVertical(y);
+            int off = layout.getOffsetForHorizontal(line, x);
+
+            ClickableSpan[] links = spannable.getSpans(off, off, ClickableSpan.class);
+
+            if (links.length != 0)
+            {
+                ClickableSpan link = links[0];
+                if (action == MotionEvent.ACTION_UP)
+                {
+                    if (link instanceof ClickableSpan)
+                    {
+                        link.onClick(widget);
+                    }
+                }
+                else if (action == MotionEvent.ACTION_DOWN)
+                {
+                    Selection.setSelection(spannable, spannable.getSpanStart(link), spannable.getSpanEnd(link));
+                }
+                return true;
+            }
+            else
+            {
+                Selection.removeSelection(spannable);
+            }
+        }
+
+        return super.onTouchEvent(widget, spannable, event);
+    }
+
+
+    public static MovementMethod getInstance()
+    {
+        if (sInstance == null)
+        {
+            sInstance = new DescriptionMovementMethod();
+        }
+
+        return sInstance;
+    }
+
+
+    private static DescriptionMovementMethod sInstance;
+}

opentasks/src/main/java/org/dmfs/tasks/widget/DescriptionFieldView.java

@@ -25,7 +25,6 @@
 import android.net.Uri;
 import android.text.Editable;
 import android.text.TextWatcher;
-import android.text.method.LinkMovementMethod;
 import android.util.AttributeSet;
 import android.view.KeyEvent;
 import android.view.LayoutInflater;
@@ -59,6 +58,7 @@
 import org.dmfs.tasks.model.FieldDescriptor;
 import org.dmfs.tasks.model.adapters.DescriptionFieldAdapter;
 import org.dmfs.tasks.model.layout.LayoutOptions;
+import org.dmfs.tasks.utils.DescriptionMovementMethod;
 
 import java.util.List;
 
@@ -242,7 +242,7 @@ private View createItemView()
         transition.disableTransitionType(LayoutTransition.CHANGING);
         transition.disableTransitionType(LayoutTransition.APPEARING);
         transition.disableTransitionType(LayoutTransition.DISAPPEARING);
-        ((TextView) item.findViewById(android.R.id.title)).setMovementMethod(LinkMovementMethod.getInstance());
+        ((TextView) item.findViewById(android.R.id.title)).setMovementMethod(DescriptionMovementMethod.getInstance());
         return item;
     }