KaTeX rendering

app/src/main/assets/katex/LICENSE

@@ -0,0 +1,21 @@
+The MIT License (MIT)
+
+Copyright (c) 2013-2020 Khan Academy and other contributors
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

app/src/main/java/fr/gaulupeau/apps/Poche/data/Settings.java

@@ -11,6 +11,12 @@
 import android.util.Log;
 import android.view.KeyEvent;
 
+import androidx.core.util.Supplier;
+
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.Set;
+
 import fr.gaulupeau.apps.InThePoche.R;
 import fr.gaulupeau.apps.Poche.App;
 import fr.gaulupeau.apps.Poche.network.ConnectivityChangeReceiver;
@@ -217,6 +223,27 @@ public void setFloat(int keyResourceID, float value) {
         setFloat(context.getString(keyResourceID), value);
     }
 
+    public Set<String> getStringSet(String key, Set<String> defValues) {
+        return pref.getStringSet(key, defValues);
+    }
+
+    public Set<String> getStringSet(int keyResourceID, Set<String> defValues) {
+        return pref.getStringSet(context.getString(keyResourceID), defValues);
+    }
+
+    public Set<String> getStringSet(int keyResourceID, Supplier<Set<String>> defValueSupplier) {
+        Set<String> set = getStringSet(keyResourceID, (Set<String>) null);
+        return set != null ? set : defValueSupplier.get();
+    }
+
+    public void setStringSet(String key, Set<String> values) {
+        pref.edit().putStringSet(key, values).apply();
+    }
+
+    public void setStringSet(int keyResourceID, Set<String> values) {
+        setStringSet(context.getString(keyResourceID), values);
+    }
+
     public String getUrl() {
         return getString(R.string.pref_key_connection_url);
     }
@@ -458,6 +485,24 @@ public void setOnyxWorkaroundEnabled(boolean value) {
         setBoolean(R.string.pref_key_ui_onyxworkaround_enabled, value);
     }
 
+    public boolean isMathRenderingEnabled() {
+        return getBoolean(R.string.pref_key_ui_mathRendering_enabled, false);
+    }
+
+    public void setMathRenderingEnabled(boolean value) {
+        setBoolean(R.string.pref_key_ui_mathRendering_enabled, value);
+    }
+
+    public Set<String> getMathRenderingDelimiters() {
+        return getStringSet(R.string.pref_key_ui_mathRendering_delimiters, () ->
+                new HashSet<>(Arrays.asList(context.getResources().getStringArray(
+                        R.array.pref_option_mathRendering_delimiters_defaultValues))));
+    }
+
+    public void setMathRenderingDelimiters(Set<String> values) {
+        setStringSet(R.string.pref_key_ui_mathRendering_delimiters, values);
+    }
+
     public boolean isTapToScrollEnabled() {
         return getBoolean(R.string.pref_key_ui_tapToScroll_enabled, false);
     }

app/src/main/java/fr/gaulupeau/apps/Poche/ui/ReadArticleActivity.java

@@ -923,6 +923,11 @@ private String getExtraHead() {
                     "\t\t<script src=\"onyx-style-workaround.js\"></script>";
         }
 
+        if (settings.isMathRenderingEnabled()) {
+            String delimiters = TextUtils.join(",", settings.getMathRenderingDelimiters());
+            extra += String.format(StorageHelper.readRawString(R.raw.katex_part), delimiters);
+        }
+
         return extra;
     }
 

app/src/main/res/raw/katex_part.html

@@ -0,0 +1,8 @@
+<link rel="stylesheet" href="katex/katex.min.css">
+<script defer src="katex/katex.min.js"></script>
+<script defer src="katex/contrib/auto-render.min.js"></script>
+<script>
+    document.addEventListener("DOMContentLoaded", function() {
+        renderMathInElement(document.body, {delimiters: [%1$s]});
+    });
+</script>

app/src/main/res/raw/webview_htmlbase.html

@@ -1,3 +1,4 @@
+<!DOCTYPE html>
 <html>
 	<head>
 		<meta name="viewport" content="initial-scale=1.0, maximum-scale=1.0, user-scalable=no" />

app/src/main/res/values/arrays.xml

@@ -27,4 +27,21 @@
         <item>XML</item>
         <item>CSV</item>
     </string-array>
+    <string-array name="pref_option_mathRendering_delimiters" translatable="false">
+        <item>\\[ … \\]</item>
+        <item>$$ … $$</item>
+        <item>\\( … \\)</item>
+        <item>$ … $</item>
+    </string-array>
+    <string-array name="pref_option_mathRendering_delimiters_values" translatable="false">
+        <item>{left: \"\\\\[\", right: \"\\\\]\", display: true}</item>
+        <item>{left: \"$$\", right: \"$$\", display: true}</item>
+        <item>{left: \"\\\\(\", right: \"\\\\)\", display: false}</item>
+        <item>{left: \"$\", right: \"$\", display: false}</item>
+    </string-array>
+    <string-array name="pref_option_mathRendering_delimiters_defaultValues" translatable="false">
+        <item>{left: \"\\\\[\", right: \"\\\\]\", display: true}</item>
+        <item>{left: \"$$\", right: \"$$\", display: true}</item>
+        <item>{left: \"\\\\(\", right: \"\\\\)\", display: false}</item>
+    </string-array>
 </resources>

app/src/main/res/values/strings-preference-keys.xml

@@ -44,6 +44,8 @@
     <string name="pref_key_ui_previewImage_enabled" translatable="false">ui.previewImage.enabled</string>
     <string name="pref_key_ui_annotations_enabled" translatable="false">ui.annotations.enabled</string>
     <string name="pref_key_ui_onyxworkaround_enabled" translatable="false">ui.onyxworkaround.enabled</string>
+    <string name="pref_key_ui_mathRendering_enabled" translatable="false">ui.mathRendering.enabled</string>
+    <string name="pref_key_ui_mathRendering_delimiters" translatable="false">ui.mathRendering.delimiters</string>
 
     <string name="pref_key_tts" translatable="false">tts</string>
     <string name="pref_key_tts_category" translatable="false">tts.category</string>

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

@@ -241,6 +241,10 @@
     <string name="pref_desc_ui_previewImage_enabled">Display the preview image before the article</string>
     <string name="pref_name_ui_annotations_enabled">Annotations support</string>
     <string name="pref_desc_ui_annotations_enabled">Experimental feature! See, edit and create annotations</string>
+    <string name="pref_name_ui_mathRendering_enabled">Math rendering</string>
+    <string name="pref_desc_ui_mathRendering_enabled">Enable LaTeX-math rendering via KaTeX</string>
+    <string name="pref_name_ui_mathRendering_delimiters">Math delimiters</string>
+    <string name="pref_desc_ui_mathRendering_delimiters">Select the environment delimiters that KaTeX should process</string>
 
     <string name="pref_categoryName_tts">Text-to-speech</string>
     <string name="pref_name_tts_fastForwardTime">Fast-forward skip time</string>

app/src/main/res/xml/preferences.xml

@@ -189,6 +189,19 @@
                 android:key="@string/pref_key_ui_annotations_enabled"
                 android:summary="@string/pref_desc_ui_annotations_enabled"
                 android:title="@string/pref_name_ui_annotations_enabled" />
+            <CheckBoxPreference
+                android:key="@string/pref_key_ui_mathRendering_enabled"
+                android:title="@string/pref_name_ui_mathRendering_enabled"
+                android:summary="@string/pref_desc_ui_mathRendering_enabled"
+                android:defaultValue="false"/>
+            <MultiSelectListPreference
+                android:key="@string/pref_key_ui_mathRendering_delimiters"
+                android:title="@string/pref_name_ui_mathRendering_delimiters"
+                android:summary="@string/pref_desc_ui_mathRendering_delimiters"
+                android:dialogTitle="@string/pref_name_ui_mathRendering_delimiters"
+                android:entries="@array/pref_option_mathRendering_delimiters"
+                android:entryValues="@array/pref_option_mathRendering_delimiters_values"
+                android:defaultValue="@array/pref_option_mathRendering_delimiters_defaultValues"/>
         </PreferenceCategory>
     </PreferenceScreen>
     <PreferenceScreen