Create additional spans

markwon-ext-spans/.gitignore

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+/build

markwon-ext-spans/build.gradle

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+plugins {
+    id 'com.android.library'
+}
+
+android {
+    compileSdkVersion 31
+
+    defaultConfig {
+        minSdkVersion 21
+        targetSdkVersion 31
+        versionCode 1
+        versionName "1.0"
+
+        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
+        consumerProguardFiles "consumer-rules.pro"
+    }
+
+    buildTypes {
+        release {
+            minifyEnabled false
+            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
+        }
+    }
+    compileOptions {
+        sourceCompatibility JavaVersion.VERSION_1_8
+        targetCompatibility JavaVersion.VERSION_1_8
+    }
+}
+
+dependencies {
+
+    implementation 'androidx.appcompat:appcompat:1.3.1'
+    implementation 'com.google.android.material:material:1.4.0'
+    testImplementation 'junit:junit:4.+'
+    androidTestImplementation 'androidx.test.ext:junit:1.1.3'
+    androidTestImplementation 'androidx.test.espresso:espresso-core:3.4.0'
+}

markwon-ext-spans/proguard-rules.pro

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+# Add project specific ProGuard rules here.
+# You can control the set of applied configuration files using the
+# proguardFiles setting in build.gradle.
+#
+# For more details, see
+#   http://developer.android.com/guide/developing/tools/proguard.html
+
+# If your project uses WebView with JS, uncomment the following
+# and specify the fully qualified class name to the JavaScript interface
+# class:
+#-keepclassmembers class fqcn.of.javascript.interface.for.webview {
+#   public *;
+#}
+
+# Uncomment this to preserve the line number information for
+# debugging stack traces.
+#-keepattributes SourceFile,LineNumberTable
+
+# If you keep the line number information, uncomment this to
+# hide the original source file name.
+#-renamesourcefileattribute SourceFile

markwon-ext-spans/src/androidTest/java/io/noties/markwon/ext/ExampleInstrumentedTest.java

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+package io.noties.markwon.ext;
+
+import android.content.Context;
+
+import androidx.test.platform.app.InstrumentationRegistry;
+import androidx.test.ext.junit.runners.AndroidJUnit4;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import static org.junit.Assert.*;
+
+/**
+ * Instrumented test, which will execute on an Android device.
+ *
+ * @see <a href="http://d.android.com/tools/testing">Testing documentation</a>
+ */
+@RunWith(AndroidJUnit4.class)
+public class ExampleInstrumentedTest {
+    @Test
+    public void useAppContext() {
+        // Context of the app under test.
+        Context appContext = InstrumentationRegistry.getInstrumentation().getTargetContext();
+        assertEquals("io.noties.markwon.ext.test", appContext.getPackageName());
+    }
+}

markwon-ext-spans/src/main/AndroidManifest.xml

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+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="io.noties.markwon.ext">
+
+</manifest>

markwon-ext-spans/src/main/java/io/noties/markwon/ext/BlockQuoteSpan.java

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+package io.noties.markwon.;
+
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.Paint;
+import android.graphics.Rect;
+import android.text.Layout;
+import android.text.Spanned;
+import android.text.style.LeadingMarginSpan;
+import android.text.style.LineHeightSpan;
+import io.noties.markwon.utils.ColorUtils;
+
+public class BlockQuoteSpan implements LeadingMarginSpan, LineHeightSpan {
+    protected int BLOCK_QUOTE_DEF_COLOR_ALPHA = 100;
+    protected static final int BLOCK_QUOTE_WIDTH = 10;
+    public static int BLOCK_QUOTE_MARGIN = 100;
+    protected int BLOCK_COLOR = Color.LTGRAY;
+    private final int VERTICAL_SPACING = 20;
+    private final Rect rect = ObjectsPool.rect();
+    private final Paint paint = ObjectsPool.paint();
+
+    public BlockQuoteSpan() {
+
+    }
+
+    @Override
+    public int getLeadingMargin(boolean first) {
+        return BLOCK_QUOTE_MARGIN;
+    }
+
+    @Override
+    public void drawLeadingMargin(
+            Canvas c,
+            Paint p,
+            int x,
+            int dir,
+            int top,
+            int baseline,
+            int bottom,
+            CharSequence text,
+            int start,
+            int end,
+            boolean first,
+            Layout layout) {
+
+        final int width = BLOCK_QUOTE_WIDTH;
+
+        paint.set(p);
+
+        applyBlockQuoteStyle(paint);
+
+        rect.set(x, top, x + dir * width, bottom);
+
+        c.drawRect(rect, paint);
+    }
+
+    public void applyBlockQuoteStyle(Paint paint) {
+        final int color = ColorUtils.applyAlpha(BLOCK_COLOR, BLOCK_QUOTE_DEF_COLOR_ALPHA);
+        paint.setStyle(Paint.Style.FILL);
+        paint.setColor(color);
+    }
+
+    @Override
+    public void chooseHeight(CharSequence text, int start, int end, int spanstartv, int lineHeight, Paint.FontMetricsInt fm) {
+        final Spanned txt = (Spanned)text;
+        final int spanEnd = txt.getSpanEnd(this);
+        final int spanStart = txt.getSpanStart(this);
+
+        // add top spacing to first line
+        if (start == spanStart) {
+            fm.ascent -= VERTICAL_SPACING;
+            fm.top -= VERTICAL_SPACING;
+        }
+
+        // add bottom spacing to last line
+        if (Math.abs(spanEnd - end) <= 1) {
+            fm.descent += VERTICAL_SPACING;
+            fm.bottom += VERTICAL_SPACING;
+        }
+    }
+}
+

markwon-ext-spans/src/main/java/io/noties/markwon/ext/BulletSpan.java

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+package io.noties.markwon.span.ext;
+
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.Paint;
+import android.graphics.Path;
+import android.graphics.Rect;
+import android.graphics.Typeface;
+import android.os.Parcel;
+import android.text.Layout;
+import android.text.ParcelableSpan;
+import android.text.Spanned;
+import android.text.TextPaint;
+import android.text.TextUtils;
+import android.text.style.LeadingMarginSpan;
+import android.text.style.MetricAffectingSpan;
+
+import androidx.annotation.ColorInt;
+import androidx.annotation.IntRange;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import androidx.annotation.Px;
+
+import com.campuswire.android.messenger.model.THEMETYPE;
+
+
+public class BulletSpan implements LeadingMarginSpan, ParcelableSpan {
+    // Bullet is slightly bigger to avoid aliasing artifacts on mdpi devices.
+    private static final int STANDARD_BULLET_RADIUS = 6;
+    public static final int STANDARD_GAP_WIDTH = 2;
+    private static final int STANDARD_COLOR = 0;
+    public static final int BULLET_SPAN = 8;
+    @Px
+    private final int mGapWidth;
+    @Px
+    private final int mBulletRadius;
+    private Path mBulletPath = null;
+    @ColorInt
+    private final int mColor;
+    private final boolean mWantColor;
+
+    /**
+     * Creates a {@link android.text.style.BulletSpan} with the default values.
+     */
+    public BulletSpan() {
+        this(STANDARD_GAP_WIDTH, STANDARD_COLOR, false, STANDARD_BULLET_RADIUS);
+    }
+
+    /**
+     * Creates a {@link android.text.style.BulletSpan} based on a gap width
+     *
+     * @param gapWidth the distance, in pixels, between the bullet point and the paragraph.
+     */
+    public BulletSpan(int gapWidth) {
+        this(gapWidth, STANDARD_COLOR, false, STANDARD_BULLET_RADIUS);
+    }
+
+    public BulletSpan(int gapWidth, @ColorInt int color) {
+        this(gapWidth, color, true, STANDARD_BULLET_RADIUS);
+    }
+
+    public BulletSpan(int gapWidth, @ColorInt int color, @IntRange(from = 0) int bulletRadius) {
+        this(gapWidth, color, true, bulletRadius);
+    }
+
+    private BulletSpan(int gapWidth, @ColorInt int color, boolean wantColor,
+                       @IntRange(from = 0) int bulletRadius) {
+        mGapWidth = gapWidth;
+        mBulletRadius = bulletRadius;
+        mColor = color;
+        mWantColor = wantColor;
+    }
+
+    public BulletSpan(@NonNull Parcel src) {
+        mGapWidth = src.readInt();
+        mWantColor = src.readInt() != 0;
+        mColor = src.readInt();
+        mBulletRadius = src.readInt();
+    }
+
+    @Override
+    public int getSpanTypeId() {
+        return getSpanTypeIdInternal();
+    }
+
+
+    public int getSpanTypeIdInternal() {
+        return BULLET_SPAN;
+    }
+
+
+    @Override
+    public int describeContents() {
+        return 0;
+    }
+
+    @Override
+    public void writeToParcel(@NonNull Parcel dest, int flags) {
+        writeToParcelInternal(dest, flags);
+    }
+
+    public void writeToParcelInternal(@NonNull Parcel dest, int flags) {
+        dest.writeInt(mGapWidth);
+        dest.writeInt(mWantColor ? 1 : 0);
+        dest.writeInt(mColor);
+        dest.writeInt(mBulletRadius);
+    }
+
+    @Override
+    public int getLeadingMargin(boolean first) {
+        return 2 * mBulletRadius + mGapWidth;
+    }
+
+    /**
+     * Get the distance, in pixels, between the bullet point and the paragraph.
+     *
+     * @return the distance, in pixels, between the bullet point and the paragraph.
+     */
+    public int getGapWidth() {
+        return mGapWidth;
+    }
+
+    /**
+     * Get the radius, in pixels, of the bullet point.
+     *
+     * @return the radius, in pixels, of the bullet point.
+     */
+    public int getBulletRadius() {
+        return mBulletRadius;
+    }
+
+    /**
+     * Get the bullet point color.
+     *
+     * @return the bullet point color
+     */
+    public int getColor() {
+        return mColor;
+    }
+
+    @Override
+    public void drawLeadingMargin(@NonNull Canvas canvas, @NonNull Paint paint, int x, int dir,
+                                  int top, int baseline, int bottom,
+                                  @NonNull CharSequence text, int start, int end,
+                                  boolean first, @Nullable Layout layout) {
+        if (((Spanned) text).getSpanStart(this) == start) {
+            Paint.Style style = paint.getStyle();
+            int oldcolor = 0;
+
+            if (mWantColor) {
+                oldcolor = paint.getColor();
+                paint.setColor(mColor);
+            }
+
+            paint.setStyle(Paint.Style.FILL);
+
+            if (layout != null) {
+                // "bottom" position might include extra space as a result of line spacing
+                // configuration. Subtract extra space in order to show bullet in the vertical
+                // center of characters.
+                final int line = layout.getLineForOffset(start);
+
+                bottom = bottom - 0;//layout.getLineExtra(line);
+            }
+
+            final float yPosition = (top + bottom) / 2f;
+            final float xPosition = x + dir * mBulletRadius;
+
+            if (canvas.isHardwareAccelerated()) {
+                if (mBulletPath == null) {
+                    mBulletPath = new Path();
+                    mBulletPath.addCircle(0.0f, 0.0f, mBulletRadius, Path.Direction.CW);
+                }
+
+                canvas.save();
+                canvas.translate(xPosition, yPosition);
+                canvas.drawPath(mBulletPath, paint);
+                canvas.restore();
+            } else {
+                canvas.drawCircle(xPosition, yPosition, mBulletRadius, paint);
+            }
+
+            if (mWantColor) {
+                paint.setColor(oldcolor);
+            }
+
+            paint.setStyle(style);
+        }
+    }
+}

markwon-ext-spans/src/main/java/io/noties/markwon/ext/CWClickableSpan.java

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+package io.noties.markwon.span.ext;
+
+import android.text.TextPaint;
+import android.text.style.ClickableSpan;
+import android.view.View;
+
+import androidx.annotation.NonNull;
+
+import com.campuswire.android.messenger.interfaces.MessageItemTapListener;
+
+public class CWClickableSpan extends ClickableSpan {
+    String userId;
+    MessageItemTapListener messageItemTapListener;
+    public CWClickableSpan(String text, MessageItemTapListener listener) {
+        super();
+        userId = text;
+        messageItemTapListener = listener;
+    }
+    @Override
+    public void onClick(@NonNull View view) {
+        messageItemTapListener.onClickUser(userId);
+    }
+
+    @Override
+    public void updateDrawState(@NonNull TextPaint ds) {
+        ds.setUnderlineText(false);
+    }
+}

markwon-ext-spans/src/main/java/io/noties/markwon/ext/CWDrawableSpan.java

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+package io.noties.markwon.span.ext;
+
+import android.graphics.drawable.Drawable;
+import android.text.style.DynamicDrawableSpan;
+
+public class CWDrawableSpan extends DynamicDrawableSpan {
+    private Drawable drawable;
+    private int requiredWidth = 0;
+    private int requiredHeight = 0;
+
+    public CWDrawableSpan(Drawable drawable){
+        this.drawable = drawable;
+    }
+
+    public CWDrawableSpan(Drawable drawable, int requiredWidth, int requiredHeight){
+        this.requiredWidth = requiredWidth;
+        this.requiredHeight = requiredHeight;
+        this.drawable = drawable;
+    }
+
+    @Override
+    public Drawable getDrawable() {
+//        drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
+        if (requiredHeight != 0 && requiredWidth != 0) {
+            drawable.setBounds(0, 0, requiredWidth, requiredHeight);
+        } else {
+            drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
+        }
+        return drawable;
+    }
+}

markwon-ext-spans/src/main/java/io/noties/markwon/ext/CenteredImageSpan.java

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+package io.noties.markwon.span.ext;
+
+import android.content.Context;
+import android.graphics.Canvas;
+import android.graphics.Paint;
+import android.graphics.Rect;
+import android.graphics.drawable.Drawable;
+import androidx.annotation.NonNull;
+import android.text.style.DynamicDrawableSpan;
+import android.text.style.ImageSpan;
+
+import java.lang.ref.WeakReference;
+
+public class CenteredImageSpan extends ImageSpan {
+    private WeakReference<Drawable> mDrawableRef;
+
+    public CenteredImageSpan(Context context, final int drawableRes) {
+        super(context, drawableRes);
+    }
+
+    public CenteredImageSpan(Drawable drawable) {
+        super(drawable);
+    }
+
+    @Override
+    public int getSize(Paint paint, CharSequence text, int start, int end,
+                       Paint.FontMetricsInt fontMetricsInt) {
+        Drawable drawable = getDrawable();
+        Rect rect = drawable.getBounds();
+        if (fontMetricsInt != null) {
+            Paint.FontMetricsInt fmPaint = paint.getFontMetricsInt();
+            int fontHeight = fmPaint.descent - fmPaint.ascent;
+            int drHeight = rect.bottom - rect.top;
+            int centerY = fmPaint.ascent + fontHeight / 2;
+
+            fontMetricsInt.ascent = centerY - drHeight / 2;
+            fontMetricsInt.top = fontMetricsInt.ascent;
+            fontMetricsInt.bottom = centerY + drHeight / 2;
+            fontMetricsInt.descent = fontMetricsInt.bottom;
+        }
+        return rect.right;
+    }
+    @Override
+    public void draw(Canvas canvas, CharSequence text, int start, int end,
+                     float x, int top, int y, int bottom, Paint paint) {
+
+        Drawable drawable = getDrawable();
+        canvas.save();
+        Paint.FontMetricsInt fmPaint = paint.getFontMetricsInt();
+        int fontHeight = fmPaint.descent - fmPaint.ascent;
+        int centerY = y + fmPaint.descent - fontHeight / 2;
+        int transY = centerY - (drawable.getBounds().bottom - drawable.getBounds().top) / 2;
+        canvas.translate(x, transY);
+        drawable.draw(canvas);
+        canvas.restore();
+    }
+}

markwon-ext-spans/src/main/java/io/noties/markwon/ext/CodeBlockSpan.java

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+package io.noties.markwon.span.ext;
+
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.Paint;
+import android.graphics.Rect;
+import android.graphics.RectF;
+import android.graphics.Typeface;
+import android.text.Layout;
+import android.text.Spanned;
+import android.text.TextPaint;
+import android.text.style.LeadingMarginSpan;
+import android.text.style.LineHeightSpan;
+import android.text.style.MetricAffectingSpan;
+
+import androidx.annotation.NonNull;
+
+import com.campuswire.android.messenger.model.THEMETYPE;
+
+import io.noties.markwon.core.MarkwonTheme;
+
+
+public class CodeBlockSpan extends MetricAffectingSpan implements LeadingMarginSpan, LineHeightSpan {
+    protected static final float CODE_DEF_TEXT_SIZE_RATIO = 1.0F;
+    protected static final int DEFAULT_LEADING_MARGIN = 20;
+    protected int BACKGROUND_COLOR;
+    protected int TEXT_COLOR;
+
+    protected static final int CORNER_RADIUS = 15;
+    private final int VERTICAL_SPACING = 40;
+
+    private final Rect rect = ObjectsPool.rect();
+    private final Paint paint = ObjectsPool.paint();
+
+    public CodeBlockSpan(String theme) {
+        if(theme.equalsIgnoreCase(THEMETYPE.DARK.toString())){
+            BACKGROUND_COLOR = Color.argb(255, 25, 26, 27);
+            TEXT_COLOR = Color.WHITE;
+        }else{
+            BACKGROUND_COLOR = Color.argb(255, 246, 246, 246);
+            TEXT_COLOR = Color.BLACK;
+        }
+    }
+
+    @Override
+    public void updateMeasureState(TextPaint p) {
+        apply(p);
+    }
+
+    @Override
+    public void updateDrawState(TextPaint ds) {
+        apply(ds);
+    }
+
+    private void apply(TextPaint p) {
+        final int textColor = TEXT_COLOR;
+
+        if (textColor != 0) {
+            paint.setColor(textColor);
+        }
+
+        paint.setTypeface(Typeface.MONOSPACE);
+
+        final int textSize = 0;
+
+        if (textSize > 0) {
+            paint.setTextSize(textSize);
+        } else {
+            // calculate default value
+            paint.setTextSize(paint.getTextSize() * CODE_DEF_TEXT_SIZE_RATIO);
+        }
+    }
+
+    @Override
+    public int getLeadingMargin(boolean first) {
+        return DEFAULT_LEADING_MARGIN;
+    }
+
+    @Override
+    public void drawLeadingMargin(Canvas c, Paint p, int x, int dir, int top, int baseline, int bottom, CharSequence text, int start, int end, boolean first, Layout layout) {
+
+        paint.setStyle(Paint.Style.FILL);
+        paint.setColor(BACKGROUND_COLOR);
+
+        final int left;
+        final int right;
+        if (dir > 0) {
+            left = x;
+            right = c.getWidth();
+        } else {
+            left = x - c.getWidth();
+            right = x;
+        }
+
+        rect.set(left, top, right, bottom);
+
+        final Spanned txt = (Spanned)text;
+        final int spanEnd = txt.getSpanEnd(this);
+        final int spanStart = txt.getSpanStart(this);
+
+        // draw rounded corner background
+        if (start == spanStart) {
+            c.drawRoundRect(new RectF(rect), CORNER_RADIUS, CORNER_RADIUS, paint);
+            c.drawRect(new Rect(left, top + CORNER_RADIUS, right, bottom), paint);
+        }
+        else if (Math.abs(spanEnd - end) <= 1) {
+            c.drawRoundRect(new RectF(rect), CORNER_RADIUS, CORNER_RADIUS, paint);
+            c.drawRect(new Rect(left, top, right, bottom - CORNER_RADIUS), paint);
+        }
+        else {
+            c.drawRect(rect, paint);
+        }
+    }
+
+    @Override
+    public void chooseHeight(CharSequence text, int start, int end, int spanstartv, int lineHeight, Paint.FontMetricsInt fm) {
+        final Spanned txt = (Spanned)text;
+        final int spanEnd = txt.getSpanEnd(this);
+        final int spanStart = txt.getSpanStart(this);
+
+        // add top spacing to first line
+        if (start == spanStart) {
+            fm.ascent -= VERTICAL_SPACING;
+            fm.top -= VERTICAL_SPACING;
+        }
+
+        // add bottom spacing to last line
+        if (Math.abs(spanEnd - end) <= 1) {
+            fm.descent += VERTICAL_SPACING;
+            fm.bottom += VERTICAL_SPACING;
+        }
+    }
+}

markwon-ext-spans/src/main/java/io/noties/markwon/ext/GifDrawableSpan.java

@@ -0,0 +1,33 @@
+package io.noties.markwon.span.ext;
+
+import android.graphics.drawable.Drawable;
+import android.text.style.DynamicDrawableSpan;
+
+import com.bumptech.glide.load.resource.gif.GifDrawable;
+
+public class GifDrawableSpan extends DynamicDrawableSpan {
+    private GifDrawable drawable;
+    private int requiredWidth = 0;
+    private int requiredHeight = 0;
+
+    public GifDrawableSpan(GifDrawable drawable){
+        this.drawable = drawable;
+    }
+
+    public GifDrawableSpan(GifDrawable drawable, int requiredWidth, int requiredHeight){
+        this.requiredWidth = requiredWidth;
+        this.requiredHeight = requiredHeight;
+        this.drawable = drawable;
+    }
+
+    @Override
+    public Drawable getDrawable() {
+//        drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
+        if (requiredHeight != 0 && requiredWidth != 0) {
+            drawable.setBounds(0, 0, requiredWidth, requiredHeight);
+        } else {
+            drawable.setBounds(0, 0, drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight());
+        }
+        return drawable;
+    }
+}

markwon-ext-spans/src/main/java/io/noties/markwon/ext/HashtagSpan.java

@@ -0,0 +1,48 @@
+package io.noties.markwon.span.ext;
+
+import android.text.TextPaint;
+import android.text.style.URLSpan;
+import android.view.View;
+
+import androidx.annotation.NonNull;
+
+import io.noties.markwon.LinkResolver;
+
+public class HashtagSpan extends URLSpan {
+    private final String link;
+    private final LinkResolver resolver;
+    private final int linkColor;
+
+    public HashtagSpan(
+            @NonNull String link,
+            @NonNull int linkColor,
+            @NonNull LinkResolver resolver) {
+        super(link);
+        this.link = link;
+        this.linkColor = linkColor;
+        this.resolver = resolver;
+    }
+
+    @Override
+    public void onClick(View widget) {
+        resolver.resolve(widget, link);
+    }
+
+    @Override
+    public void updateDrawState(@NonNull TextPaint ds) {
+        applyLinkStyle(ds);
+    }
+
+    private void applyLinkStyle(TextPaint paint){
+        paint.setUnderlineText(true);
+        paint.setColor(linkColor);
+    }
+
+    /**
+     * @since 4.2.0
+     */
+    @NonNull
+    public String getLink() {
+        return link;
+    }
+}

markwon-ext-spans/src/main/java/io/noties/markwon/ext/NumberedSpan.java

@@ -0,0 +1,60 @@
+package io.noties.markwon.span.ext;
+
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.Paint;
+import android.graphics.Rect;
+import android.text.Layout;
+import android.text.Spanned;
+import android.text.style.LeadingMarginSpan;
+
+import com.campuswire.android.messenger.model.THEMETYPE;
+
+class NumberedSpan implements LeadingMarginSpan {
+    private final int NUMBER_GAP = 14;
+    private final int mIndex;
+    private final String mTheme;
+    private final Paint paint = ObjectsPool.paint();
+
+    NumberedSpan(int index, String  theme) {
+        mIndex = index;
+        mTheme = theme;
+    }
+
+    @Override
+    public int getLeadingMargin(boolean first) {
+        final String numText = mIndex + ".";
+        final Rect textBounds = new Rect();
+        paint.getTextBounds(numText, 0, numText.length(), textBounds);
+        return textBounds.width() + NUMBER_GAP;
+    }
+
+    @Override
+    public void drawLeadingMargin(Canvas canvas, Paint paint, int x, int dir, int top, int baseline,
+                                  int bottom, CharSequence text, int start, int end, boolean first,
+                                  Layout layout) {
+        // add number to first line
+        if (((Spanned)text).getSpanStart(this) == start) {
+            // save previous paint values
+            final Paint.Style prevStyle = paint.getStyle();
+            final int prevColor = paint.getColor();
+
+            // draw number
+            paint.setStyle(Paint.Style.FILL);
+            if(mTheme.equalsIgnoreCase(THEMETYPE.DARK.toString())){
+                paint.setColor(Color.WHITE);
+            }else{
+                paint.setColor(Color.BLACK);
+            }
+            final String numText = mIndex + ".";
+            final Rect textBounds = new Rect();
+            paint.getTextBounds(numText, 0, numText.length(), textBounds);
+            final float yVal = (top + bottom + textBounds.height()) / 2f;
+            canvas.drawText(numText, 0, numText.length(), x, yVal, paint);
+
+            // reset modified paint values
+            paint.setStyle(prevStyle);
+            paint.setColor(prevColor);
+        }
+    }
+}

markwon-ext-spans/src/main/java/io/noties/markwon/ext/ObjectsPool.java

@@ -0,0 +1,33 @@
+package io.noties.markwon.span.ext;
+
+import android.graphics.Paint;
+import android.graphics.Rect;
+import android.graphics.RectF;
+
+abstract class ObjectsPool {
+
+    // maybe it's premature optimization, but as all the drawing is done in one thread
+    // and we apply needed values before actual drawing it's (I assume) safe to reuse some frequently used objects
+
+    // if one of the spans need some really specific handling for Paint object (like colorFilters, masks, etc)
+    // it should instantiate own instance of it
+
+    private static final Rect RECT = new Rect();
+    private static final RectF RECT_F = new RectF();
+    private static final Paint PAINT = new Paint(Paint.ANTI_ALIAS_FLAG);
+
+    static Rect rect() {
+        return RECT;
+    }
+
+    static RectF rectF() {
+        return RECT_F;
+    }
+
+    static Paint paint() {
+        return PAINT;
+    }
+
+    private ObjectsPool() {
+    }
+}

markwon-ext-spans/src/test/java/io/noties/markwon/ext/ExampleUnitTest.java

@@ -0,0 +1,17 @@
+package io.noties.markwon.ext;
+
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+/**
+ * Example local unit test, which will execute on the development machine (host).
+ *
+ * @see <a href="http://d.android.com/tools/testing">Testing documentation</a>
+ */
+public class ExampleUnitTest {
+    @Test
+    public void addition_isCorrect() {
+        assertEquals(4, 2 + 2);
+    }
+}