Add E-Ink mode

app/src/main/java/com/hippo/easyrecyclerview/HandlerDrawable.java

@@ -0,0 +1,84 @@
+/*
+ * Copyright 2015 Hippo Seven
+ *
+ * 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.hippo.easyrecyclerview;
+
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.ColorFilter;
+import android.graphics.Paint;
+import android.graphics.PixelFormat;
+import android.graphics.RectF;
+import android.graphics.drawable.Drawable;
+
+public class HandlerDrawable extends Drawable {
+
+    private int mColor = Color.BLACK;
+    private final Paint mPaint;
+    private final RectF mTemp = new RectF();
+
+    public HandlerDrawable() {
+        mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
+        mPaint.setColor(mColor);
+        mPaint.setStyle(Paint.Style.FILL);
+    }
+
+    @Override
+    public void draw(Canvas canvas) {
+        int width = getBounds().width();
+        int height = getBounds().height();
+
+        if (width > height) {
+            canvas.drawRect(0, 0, width, height, mPaint);
+        } else {
+            mTemp.set(0, 0, width, width);
+            canvas.drawArc(mTemp, -180, 180, true, mPaint);
+            mTemp.set(0, height - width, width, height);
+            canvas.drawArc(mTemp, 0, 180, true, mPaint);
+            float halfWidth = (float) width / 2.0f;
+            canvas.drawRect(0, halfWidth, width, height - halfWidth, mPaint);
+        }
+    }
+
+    public void setColor(int color) {
+        if (mColor != color) {
+            mColor = color;
+            mPaint.setColor(color);
+        }
+    }
+
+    @Override
+    public void setAlpha(int alpha) {
+        mPaint.setAlpha(alpha);
+    }
+
+    @Override
+    public void setColorFilter(ColorFilter colorFilter) {
+        mPaint.setColorFilter(colorFilter);
+    }
+
+    @Override
+    public int getOpacity() {
+        int alpha = Color.alpha(mColor);
+        if (alpha == 0xff) {
+            return PixelFormat.OPAQUE;
+        } else if (alpha == 0x00) {
+            return PixelFormat.TRANSPARENT;
+        } else {
+            return PixelFormat.TRANSLUCENT;
+        }
+    }
+}