From 55004531ebe15d5219b01d7949ee6fa7f2d340b1 Mon Sep 17 00:00:00 2001
From: serso <se.solovyev@gmail.com>
Date: Wed, 11 May 2016 23:30:30 +0200
Subject: [PATCH] Don't show shadow for text with light color

---
 .../views/dragbutton/DirectionDragButton.java |  2 +-
 .../views/dragbutton/DirectionTextView.java   | 27 +++++++++++++++----
 2 files changed, 23 insertions(+), 6 deletions(-)

diff --git a/app/src/main/java/org/solovyev/android/views/dragbutton/DirectionDragButton.java b/app/src/main/java/org/solovyev/android/views/dragbutton/DirectionDragButton.java
index 3d44f3e2..0d3c69ad 100644
--- a/app/src/main/java/org/solovyev/android/views/dragbutton/DirectionDragButton.java
+++ b/app/src/main/java/org/solovyev/android/views/dragbutton/DirectionDragButton.java
@@ -100,7 +100,7 @@ public class DirectionDragButton extends DragButton implements DirectionDragView
         }
         this.highContrast = highContrast;
         this.textView.setHighContrast(highContrast);
-        if (highContrast) {
+        if (highContrast && DirectionTextView.needsShadow(getCurrentTextColor())) {
             setShadowLayer(applyDimension(COMPLEX_UNIT_DIP, SHADOW_RADIUS_DPS, getResources().getDisplayMetrics()), 0, 0, BLACK);
         } else {
             setShadowLayer(0, 0, 0, BLACK);
diff --git a/app/src/main/java/org/solovyev/android/views/dragbutton/DirectionTextView.java b/app/src/main/java/org/solovyev/android/views/dragbutton/DirectionTextView.java
index f268318c..3af01572 100644
--- a/app/src/main/java/org/solovyev/android/views/dragbutton/DirectionTextView.java
+++ b/app/src/main/java/org/solovyev/android/views/dragbutton/DirectionTextView.java
@@ -3,20 +3,20 @@ package org.solovyev.android.views.dragbutton;
 import android.content.Context;
 import android.content.res.TypedArray;
 import android.graphics.Canvas;
-import android.graphics.Color;
 import android.graphics.PointF;
 import android.graphics.Rect;
 import android.graphics.Typeface;
+import android.support.annotation.ColorInt;
 import android.support.annotation.NonNull;
 import android.support.annotation.Nullable;
+import android.support.v4.content.ContextCompat;
+import android.support.v4.graphics.ColorUtils;
 import android.text.TextPaint;
 import android.text.TextUtils;
 import android.util.AttributeSet;
 import android.view.View;
 import android.widget.TextView;
-
 import com.google.common.base.Strings;
-
 import org.solovyev.android.Check;
 import org.solovyev.android.calculator.R;
 
@@ -111,6 +111,7 @@ public class DirectionTextView {
         private String value = "";
         private float scale;
         private int color;
+        private int contrastColor;
         private float alpha;
         private boolean visible = true;
         private boolean highContrast;
@@ -136,9 +137,15 @@ public class DirectionTextView {
             }
             alpha = defAlpha;
             color = defColor;
+            contrastColor = makeContrastColor(color);
             initPaint(base);
         }
 
+        private int makeContrastColor(int color) {
+            final int colorRes = isLightColor(color) ? R.color.cpp_button_text : R.color.cpp_text_inverse;
+            return ContextCompat.getColor(view.getContext(), colorRes);
+        }
+
         public void initPaint(@NonNull TextPaint base) {
             paint.set(base);
             paint.setColor(color);
@@ -161,7 +168,7 @@ public class DirectionTextView {
         }
 
         private void initPaintShadow() {
-            if (highContrast) {
+            if (highContrast && needsShadow(color)) {
                 paint.setShadowLayer(applyDimension(COMPLEX_UNIT_DIP, SHADOW_RADIUS_DPS, view.getResources().getDisplayMetrics()), 0, 0, BLACK);
             } else {
                 paint.setShadowLayer(0, 0, 0, BLACK);
@@ -202,9 +209,11 @@ public class DirectionTextView {
                 return;
             }
             this.color = color;
+            this.contrastColor = makeContrastColor(color);
             this.alpha = alpha;
             paint.setColor(color);
             paint.setAlpha(intAlpha());
+            initPaintShadow();
             invalidate(false);
         }
 
@@ -224,7 +233,7 @@ public class DirectionTextView {
                 calculatePosition();
             }
             if (highContrast) {
-                paint.setColor(Color.WHITE);
+                paint.setColor(contrastColor);
                 paint.setAlpha(255);
             }
             final int width = view.getWidth();
@@ -296,4 +305,12 @@ public class DirectionTextView {
             return visible && !TextUtils.isEmpty(value);
         }
     }
+
+    private static boolean isLightColor(@ColorInt int color) {
+        return ColorUtils.calculateLuminance(color) > 0.5f;
+    }
+
+    public static boolean needsShadow(@ColorInt int color) {
+        return isLightColor(color);
+    }
 }