Added links to scanning settings

Bug: 19918721
Change-Id: Ifb1508807d34b675e9ea1522f86a9310ed6b663f

src/com/android/settings/LinkifyUtils.java

@@ -0,0 +1,84 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.settings;
+
+import android.text.Spannable;
+import android.text.TextPaint;
+import android.text.method.LinkMovementMethod;
+import android.text.style.ClickableSpan;
+import android.view.View;
+import android.widget.TextView;
+import android.widget.TextView.BufferType;
+
+/**
+ * Utility class to create clickable links inside {@link TextView TextViews}.
+ */
+public class LinkifyUtils {
+    private static final String PLACE_HOLDER_LINK_BEGIN = "LINK_BEGIN";
+    private static final String PLACE_HOLDER_LINK_END = "LINK_END";
+
+    private LinkifyUtils() {
+    }
+
+    /** Interface that handles the click event of the link */
+    public interface OnClickListener {
+        void onClick();
+    }
+
+    /**
+     * Applies the text into the {@link TextView} and part of it a clickable link.
+     * The text surrounded with "LINK_BEGIN" and "LINK_END" will become a clickable link. Only
+     * supports at most one link.
+     * @return true if the link has been successfully applied, or false if the original text
+     *         contains no link place holders.
+     */
+    public static boolean linkify(TextView textView, StringBuilder text,
+            final OnClickListener listener) {
+        // Remove place-holders from the string and record their positions
+        final int beginIndex = text.indexOf(PLACE_HOLDER_LINK_BEGIN);
+        if (beginIndex == -1) {
+            textView.setText(text);
+            return false;
+        }
+        text.delete(beginIndex, beginIndex + PLACE_HOLDER_LINK_BEGIN.length());
+        final int endIndex = text.indexOf(PLACE_HOLDER_LINK_END);
+        if (endIndex == -1) {
+            textView.setText(text);
+            return false;
+        }
+        text.delete(endIndex, endIndex + PLACE_HOLDER_LINK_END.length());
+
+        textView.setText(text.toString(), BufferType.SPANNABLE);
+        textView.setMovementMethod(LinkMovementMethod.getInstance());
+        Spannable spannableContent = (Spannable) textView.getText();
+        ClickableSpan spannableLink = new ClickableSpan() {
+            @Override
+            public void onClick(View widget) {
+                listener.onClick();
+            }
+
+            @Override
+            public void updateDrawState(TextPaint ds) {
+                super.updateDrawState(ds);
+                ds.setUnderlineText(false);
+            }
+        };
+        spannableContent.setSpan(spannableLink, beginIndex, endIndex,
+                Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
+        return true;
+    }
+}