Add clickable spans for #stream-name.

Author: Sam1301

app/src/main/java/com/zulip/android/activities/ZulipActivity.java

@@ -21,7 +21,6 @@
 import android.database.MergeCursor;
 import android.graphics.Bitmap;
 import android.graphics.PorterDuff;
-import android.graphics.Rect;
 import android.graphics.drawable.Drawable;
 import android.net.Uri;
 import android.os.Build;
@@ -52,13 +51,11 @@
 import android.text.TextWatcher;
 import android.util.Log;
 import android.util.TypedValue;
-import android.view.Gravity;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.View;
 import android.view.ViewPropertyAnimator;
 import android.view.WindowManager;
-import android.view.Window;
 import android.view.animation.Interpolator;
 import android.view.inputmethod.InputMethodManager;
 import android.widget.AdapterView;
@@ -1301,7 +1298,7 @@ public void onClick(View v) {
      *
      * @param streamName stream name
      */
-    private void doNarrowToLastRead(String streamName) {
+    public void doNarrowToLastRead(String streamName) {
         // get last message read in stream
         Message message = Stream.getLastMessageRead(app, streamName);
         if (message != null) {

app/src/main/java/com/zulip/android/util/CustomHtmlToSpannedConverter.java

@@ -54,6 +54,7 @@
 import com.zulip.android.R;
 import com.zulip.android.ZulipApp;
 import com.zulip.android.models.Person;
+import com.zulip.android.models.Stream;
 
 import org.ccil.cowan.tagsoup.Parser;
 import org.xml.sax.Attributes;
@@ -87,6 +88,7 @@ public class CustomHtmlToSpannedConverter implements ContentHandler {
     private Html.ImageGetter mEmojiGetter;
     private String mBaseUri;
     private boolean isCode;
+    private boolean isStreamLink;
 
     public CustomHtmlToSpannedConverter(String source,
                                         Html.ImageGetter imageGetter, Html.TagHandler tagHandler,
@@ -271,6 +273,30 @@ private static void endSpan(SpannableStringBuilder text) {
         }
     }
 
+    private static void startStreamA(SpannableStringBuilder text, Attributes attributes) {
+        /**
+         example: <a class="stream" data-stream-id="4" href="/#narrow/stream/android">#android</a>
+         */
+        String streamId = attributes.getValue("data-stream-id");
+
+        int len = text.length();
+        text.setSpan(new Href(streamId), len, len, Spannable.SPAN_MARK_MARK);
+    }
+
+    private static void endStreamA(SpannableStringBuilder text) {
+        int len = text.length();
+        Object obj = getLast(text, Href.class);
+        int where = text.getSpanStart(obj);
+        text.removeSpan(obj);
+        if (where != len) {
+            Href h = (Href) obj;
+            if (h != null && h.mHref != null) {
+                text.setSpan(new StreamSpan(h.mHref, 0xFF0088cc), where, len,
+                        Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
+            }
+        }
+    }
+
     private static void startA(SpannableStringBuilder text,
                                Attributes attributes, String baseUri) {
         String href = attributes.getValue("", "href");
@@ -515,7 +541,12 @@ private void handleStartTag(String tag, Attributes attributes) {
         } else if (tag.equalsIgnoreCase("tt")) {
             start(mSpannableStringBuilder, new Monospace());
         } else if (tag.equalsIgnoreCase("a")) {
-            startA(mSpannableStringBuilder, attributes, mBaseUri);
+            if ("stream".equalsIgnoreCase(attributes.getValue("class"))) {
+                startStreamA(mSpannableStringBuilder, attributes);
+                isStreamLink = true;
+            } else {
+                startA(mSpannableStringBuilder, attributes, mBaseUri);
+            }
         } else if (tag.equalsIgnoreCase("span")
                 && "user-mention".equals(attributes.getValue("class"))) {
             startSpan(mSpannableStringBuilder, attributes);
@@ -594,7 +625,12 @@ private void handleEndTag(String tag) {
             end(mSpannableStringBuilder, Monospace.class, new TypefaceSpan(
                     MONOSPACE));
         } else if (tag.equalsIgnoreCase("a")) {
-            endA(mSpannableStringBuilder);
+            if (isStreamLink) {
+                endStreamA(mSpannableStringBuilder);
+                isStreamLink = true;
+            } else {
+                endA(mSpannableStringBuilder);
+            }
         } else if (tag.equalsIgnoreCase("span")) {
             endSpan(mSpannableStringBuilder);
         } else if (tag.equalsIgnoreCase("u")) {

app/src/main/java/com/zulip/android/util/StreamSpan.java

@@ -0,0 +1,53 @@
+package com.zulip.android.util;
+
+import android.content.Context;
+import android.text.TextPaint;
+import android.text.style.ClickableSpan;
+import android.view.View;
+
+import com.zulip.android.ZulipApp;
+import com.zulip.android.models.Stream;
+
+/**
+ * Custom ClickableSpan to support #stream-name click. The user is taken to the last message read
+ * in the stream.
+ */
+
+public class StreamSpan extends ClickableSpan {
+    private String streamId;
+    private int color;
+
+    public StreamSpan(String streamId, int color) {
+        this.streamId = streamId;
+        this.color = color;
+    }
+
+    /**
+     * Performs the click action associated with this span.
+     */
+    @Override
+    public void onClick(View widget) {
+        Context context = widget.getContext().getApplicationContext();
+
+        // get stream name from streamId string
+        String streamName = null;
+        if (streamId != null) {
+            Stream stream = Stream.getById(ZulipApp.get(), Integer.parseInt(streamId));
+            if (stream != null) {
+                streamName = stream.getName();
+            }
+        }
+
+        // go to last message read in the stream
+        (((ZulipApp) context).getZulipActivity()).doNarrowToLastRead(streamName);
+    }
+
+    /**
+     * Makes the text underlined and in the link color.
+     */
+    @Override
+    public void updateDrawState(TextPaint ds) {
+        ds.setColor(this.color);
+        ds.setUnderlineText(false);
+    }
+}