Add Curved Slices to Pie Chart

Finally added support for rounded slices, and somewhat improved the code
for the PieChartRenderer class.

Author: almic

MPChartExample/src/main/java/com/xxmassdeveloper/mpchartexample/PieChartActivity.java

@@ -210,6 +210,18 @@ public boolean onOptionsItemSelected(MenuItem item) {
                 chart.invalidate();
                 break;
             }
+            case R.id.actionToggleCurvedSlices: {
+                boolean toSet = !chart.isDrawRoundedSlicesEnabled() || !chart.isDrawHoleEnabled();
+                chart.setDrawRoundedSlices(toSet);
+                if (toSet && !chart.isDrawHoleEnabled()) {
+                    chart.setDrawHoleEnabled(true);
+                }
+                if (toSet && chart.isDrawSlicesUnderHoleEnabled()) {
+                    chart.setDrawSlicesUnderHole(false);
+                }
+                chart.invalidate();
+                break;
+            }
             case R.id.actionDrawCenter: {
                 if (chart.isDrawCenterTextEnabled())
                     chart.setDrawCenterText(false);

MPChartExample/src/main/java/com/xxmassdeveloper/mpchartexample/PiePolylineChartActivity.java

@@ -205,6 +205,18 @@ public boolean onOptionsItemSelected(MenuItem item) {
                 chart.invalidate();
                 break;
             }
+            case R.id.actionToggleCurvedSlices: {
+                boolean toSet = !chart.isDrawRoundedSlicesEnabled() || !chart.isDrawHoleEnabled();
+                chart.setDrawRoundedSlices(toSet);
+                if (toSet && !chart.isDrawHoleEnabled()) {
+                    chart.setDrawHoleEnabled(true);
+                }
+                if (toSet && chart.isDrawSlicesUnderHoleEnabled()) {
+                    chart.setDrawSlicesUnderHole(false);
+                }
+                chart.invalidate();
+                break;
+            }
             case R.id.actionDrawCenter: {
                 if (chart.isDrawCenterTextEnabled())
                     chart.setDrawCenterText(false);

MPChartExample/src/main/res/menu/pie.xml

@@ -25,6 +25,10 @@
         android:id="@+id/actionToggleHole"
         android:title="@string/actionToggleHole">
     </item>
+    <item
+        android:id="@+id/actionToggleCurvedSlices"
+        android:title="@string/actionToggleCurvedSlices">
+    </item>
     <item
         android:id="@+id/actionDrawCenter"
         android:title="@string/actionDrawCenterText">

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

@@ -41,6 +41,7 @@
 
     <string name="actionTogglePercent">Toggle Percent</string>
     <string name="actionToggleHole">Toggle Hole</string>
+    <string name="actionToggleCurvedSlices">Toggle Curved Slices</string>
     <string name="actionDrawCenterText">Draw Center Text</string>
     <string name="actionToggleHighlightCircle">Toggle Highlight Circle</string>
     <string name="actionToggleRotation">Toggle Rotation</string>

MPChartLib/src/main/java/com/github/mikephil/charting/charts/PieChart.java

@@ -650,6 +650,16 @@ public void setEntryLabelTextSize(float size) {
         ((PieChartRenderer) mRenderer).getPaintEntryLabels().setTextSize(Utils.convertDpToPixel(size));
     }
 
+    /**
+     * Sets whether to draw slices in a curved fashion, only works if drawing the hole is enabled
+     * and if the slices are not drawn under the hole.
+     *
+     * @param enabled draw curved ends of slices
+     */
+    public void setDrawRoundedSlices(boolean enabled) {
+        mDrawRoundedSlices = enabled;
+    }
+
     /**
      * Returns true if the chart is set to draw each end of a pie-slice
      * "rounded".