Fix transparency on widgets

app/src/androidTest/java/org/isoron/uhabits/unit/views/HabitScoreViewTest.java

@@ -62,7 +62,7 @@ public class HabitScoreViewTest extends ViewTest
     @Test
     public void testRender_withTransparentBackground() throws Throwable
     {
-        view.setIsBackgroundTransparent(true);
+        view.setIsTransparencyEnabled(true);
         assertRenders(view, "HabitScoreView/renderTransparent.png");
     }
 

app/src/main/java/org/isoron/uhabits/views/CheckmarkWidgetView.java

@@ -62,6 +62,8 @@ public class CheckmarkWidgetView extends HabitWidgetView implements HabitDataVie
         ring = (RingView) findViewById(R.id.scoreRing);
         label = (TextView) findViewById(R.id.label);
 
+        if(ring != null) ring.setIsTransparencyEnabled(true);
+
         if(isInEditMode())
         {
             percentage = 0.75f;

app/src/main/java/org/isoron/uhabits/views/HabitScoreView.java

@@ -20,7 +20,9 @@
 package org.isoron.uhabits.views;
 
 import android.content.Context;
+import android.graphics.Bitmap;
 import android.graphics.Canvas;
+import android.graphics.Color;
 import android.graphics.Paint;
 import android.graphics.PorterDuff;
 import android.graphics.PorterDuffXfermode;
@@ -71,11 +73,14 @@ public class HabitScoreView extends ScrollableDataView implements HabitDataView
     private int[] scores;
 
     private int primaryColor;
-    private boolean isBackgroundTransparent;
     private int bucketSize = 7;
     private int footerHeight;
     private int backgroundColor;
 
+    private Bitmap drawingCache;
+    private Canvas cacheCanvas;
+    private boolean isTransparencyEnabled;
+
     public HabitScoreView(Context context)
     {
         super(context);
@@ -168,6 +173,13 @@ public class HabitScoreView extends ScrollableDataView implements HabitDataView
         pGraph.setTextSize(baseSize * 0.5f);
         pGraph.setStrokeWidth(baseSize * 0.1f);
         pGrid.setStrokeWidth(baseSize * 0.025f);
+
+        if(isTransparencyEnabled)
+        {
+            if (drawingCache != null) drawingCache.recycle();
+            drawingCache = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
+            cacheCanvas = new Canvas(drawingCache);
+        }
     }
 
     public void refreshData()
@@ -206,12 +218,24 @@ public class HabitScoreView extends ScrollableDataView implements HabitDataView
     protected void onDraw(Canvas canvas)
     {
         super.onDraw(canvas);
+        Canvas activeCanvas;
+
+        if(isTransparencyEnabled)
+        {
+            activeCanvas = cacheCanvas;
+            drawingCache.eraseColor(Color.TRANSPARENT);
+        }
+        else
+        {
+            activeCanvas = canvas;
+        }
+
         if (habit == null || scores == null) return;
 
         rect.set(0, 0, nColumns * columnWidth, columnHeight);
         rect.offset(0, paddingTop);
 
-        drawGrid(canvas, rect);
+        drawGrid(activeCanvas, rect);
 
         pText.setColor(textColor);
         pGraph.setColor(primaryColor);
@@ -241,20 +265,23 @@ public class HabitScoreView extends ScrollableDataView implements HabitDataView
 
             if (!prevRect.isEmpty())
             {
-                drawLine(canvas, prevRect, rect);
+                drawLine(activeCanvas, prevRect, rect);
-                drawMarker(canvas, prevRect);
+                drawMarker(activeCanvas, prevRect);
             }
 
-            if (k == nColumns - 1) drawMarker(canvas, rect);
+            if (k == nColumns - 1) drawMarker(activeCanvas, rect);
 
             prevRect.set(rect);
             rect.set(0, 0, columnWidth, columnHeight);
             rect.offset(k * columnWidth, paddingTop);
 
-            drawFooter(canvas, rect, currentDate);
+            drawFooter(activeCanvas, rect, currentDate);
 
             currentDate += bucketSize * DateHelper.millisecondsInOneDay;
         }
+
+        if(activeCanvas != canvas)
+            canvas.drawBitmap(drawingCache, 0, 0, null);
     }
 
     private int skipYear = 0;
@@ -352,19 +379,19 @@ public class HabitScoreView extends ScrollableDataView implements HabitDataView
         setModeOrColor(pGraph, XFERMODE_CLEAR, backgroundColor);
         canvas.drawOval(rect, pGraph);
 
-        if(isBackgroundTransparent)
+        if(isTransparencyEnabled)
             pGraph.setXfermode(XFERMODE_SRC);
     }
 
-    public void setIsBackgroundTransparent(boolean isBackgroundTransparent)
+    public void setIsTransparencyEnabled(boolean enabled)
     {
-        this.isBackgroundTransparent = isBackgroundTransparent;
+        this.isTransparencyEnabled = enabled;
         createColors();
     }
 
     private void setModeOrColor(Paint p, PorterDuffXfermode mode, int color)
     {
-        if(isBackgroundTransparent)
+        if(isTransparencyEnabled)
             p.setXfermode(mode);
         else
             p.setColor(color);

app/src/main/java/org/isoron/uhabits/views/RingView.java

@@ -21,8 +21,12 @@ package org.isoron.uhabits.views;
 
 import android.annotation.SuppressLint;
 import android.content.Context;
+import android.graphics.Bitmap;
 import android.graphics.Canvas;
+import android.graphics.Color;
 import android.graphics.Paint;
+import android.graphics.PorterDuff;
+import android.graphics.PorterDuffXfermode;
 import android.graphics.RectF;
 import android.text.TextPaint;
 import android.util.AttributeSet;
@@ -34,6 +38,9 @@ import org.isoron.uhabits.helpers.UIHelper;
 
 public class RingView extends View
 {
+    public static final PorterDuffXfermode XFERMODE_CLEAR =
+            new PorterDuffXfermode(PorterDuff.Mode.CLEAR);
+
     private float precision;
     private boolean enableFontAwesome;
 
@@ -43,9 +50,7 @@ public class RingView extends View
     private RectF rect;
 
     private int diameter;
-
     private float textSize;
-
     private float thickness;
 
     private Integer backgroundColor;
@@ -53,6 +58,10 @@ public class RingView extends View
     private float em;
     private String text;
 
+    private Bitmap drawingCache;
+    private Canvas cacheCanvas;
+    private boolean isTransparencyEnabled;
+
     public RingView(Context context)
     {
         super(context);
@@ -155,31 +164,68 @@ public class RingView extends View
         setMeasuredDimension(diameter, diameter);
     }
 
+    @Override
+    protected void onSizeChanged(int w, int h, int oldw, int oldh)
+    {
+        super.onSizeChanged(w, h, oldw, oldh);
+
+        if(isTransparencyEnabled)
+        {
+            if (drawingCache != null) drawingCache.recycle();
+            drawingCache = Bitmap.createBitmap(diameter, diameter, Bitmap.Config.ARGB_8888);
+            cacheCanvas = new Canvas(drawingCache);
+        }
+    }
+
     @Override
     protected void onDraw(Canvas canvas)
     {
         super.onDraw(canvas);
+        Canvas activeCanvas;
+
+        if(isTransparencyEnabled)
+        {
+            activeCanvas = cacheCanvas;
+            drawingCache.eraseColor(Color.TRANSPARENT);
+        }
+        else
+        {
+            activeCanvas = canvas;
+        }
 
         pRing.setColor(color);
         rect.set(0, 0, diameter, diameter);
 
         float angle = 360 * Math.round(percentage / precision) * precision;
 
-        canvas.drawArc(rect, -90, angle, true, pRing);
+        activeCanvas.drawArc(rect, -90, angle, true, pRing);
 
         pRing.setColor(inactiveColor);
-        canvas.drawArc(rect, angle - 90, 360 - angle, true, pRing);
+        activeCanvas.drawArc(rect, angle - 90, 360 - angle, true, pRing);
 
         if(thickness > 0)
         {
-            pRing.setColor(backgroundColor);
+            if(isTransparencyEnabled)
+                pRing.setXfermode(XFERMODE_CLEAR);
+            else
+                pRing.setColor(backgroundColor);
+
             rect.inset(thickness, thickness);
-            canvas.drawArc(rect, 0, 360, true, pRing);
+            activeCanvas.drawArc(rect, 0, 360, true, pRing);
+            pRing.setXfermode(null);
 
             pRing.setColor(color);
             pRing.setTextSize(textSize);
             if(enableFontAwesome) pRing.setTypeface(UIHelper.getFontAwesome(getContext()));
-            canvas.drawText(text, rect.centerX(), rect.centerY() + 0.4f * em, pRing);
+            activeCanvas.drawText(text, rect.centerX(), rect.centerY() + 0.4f * em, pRing);
         }
+
+        if(activeCanvas != canvas)
+            canvas.drawBitmap(drawingCache, 0, 0, null);
+    }
+
+    public void setIsTransparencyEnabled(boolean isTransparencyEnabled)
+    {
+        this.isTransparencyEnabled = isTransparencyEnabled;
     }
 }

app/src/main/java/org/isoron/uhabits/widgets/ScoreWidgetProvider.java

@@ -35,7 +35,7 @@ public class ScoreWidgetProvider extends BaseWidgetProvider
     protected View buildCustomView(Context context, Habit habit)
     {
         HabitScoreView dataView = new HabitScoreView(context);
-        dataView.setIsBackgroundTransparent(true);
+        dataView.setIsTransparencyEnabled(true);
         GraphWidgetView view = new GraphWidgetView(context, dataView);
         view.setHabit(habit);
         return view;