Add radar layer custom color support

MPChartExample/build.gradle

@@ -6,7 +6,7 @@ android {
     compileSdkVersion 31
     defaultConfig {
         applicationId "com.xxmassdeveloper.mpchartexample"
-        minSdkVersion 16
+        minSdkVersion 19
         targetSdkVersion 31
         versionCode 57
         versionName '3.1.0'

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

@@ -29,6 +29,7 @@
 import com.xxmassdeveloper.mpchartexample.notimportant.DemoBase;
 
 import java.util.ArrayList;
+import java.util.List;
 
 public class RadarChartActivity extends DemoBase {
 
@@ -147,6 +148,13 @@ private void setData() {
         data.setValueTextColor(Color.WHITE);
 
         chart.setData(data);
+        List<Integer> colorList = new ArrayList<>();
+        colorList.add(Color.rgb(222, 166, 111));
+        colorList.add(Color.rgb(220, 206, 138));
+        colorList.add(Color.rgb(243, 255, 192));
+        colorList.add(Color.rgb(240, 255, 240));
+        colorList.add(Color.rgb(250, 255, 250));
+        chart.setLayerColorList(colorList);
         chart.invalidate();
     }
 

MPChartLib/build.gradle

@@ -6,7 +6,7 @@ plugins {
 android {
     compileSdkVersion 31
     defaultConfig {
-        minSdkVersion 14
+        minSdkVersion 19
         targetSdkVersion 31
 
         consumerProguardFiles 'proguard-project.txt'

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

@@ -16,6 +16,8 @@
 import com.github.mikephil.charting.renderer.YAxisRendererRadarChart;
 import com.github.mikephil.charting.utils.Utils;
 
+import java.util.List;
+
 /**
  * Implementation of the RadarChart, a "spidernet"-like chart. It works best
  * when displaying 5-10 entries per DataSet.
@@ -64,6 +66,8 @@ public class RadarChart extends PieRadarChartBase<RadarData> {
      */
     private YAxis mYAxis;
 
+    private List<Integer> colorList;
+
     protected YAxisRendererRadarChart mYAxisRenderer;
     protected XAxisRendererRadarChart mXAxisRenderer;
 
@@ -179,6 +183,25 @@ public float getSliceAngle() {
         return 360f / (float) mData.getMaxEntryCountSet().getEntryCount();
     }
 
+
+    public void setLayerColorList(List<Integer> colorList) {
+        if (colorList == null || colorList.size() == 0) {
+            return;
+        }
+        this.colorList = colorList;
+    }
+
+    public boolean isCustomLayerColorEnable() {
+        if (mData == null) {
+            return false;
+        }
+        return colorList != null && colorList.size() == getYAxis().mEntryCount;
+    }
+
+    public List<Integer> getLayerColorList() {
+        return colorList;
+    }
+
     @Override
     public int getIndexForAngle(float angle) {
 

MPChartLib/src/main/java/com/github/mikephil/charting/renderer/RadarChartRenderer.java

@@ -28,6 +28,12 @@ public class RadarChartRenderer extends LineRadarRenderer {
     protected Paint mWebPaint;
     protected Paint mHighlightCirclePaint;
 
+    private Paint paint = new Paint(Paint.ANTI_ALIAS_FLAG);
+    private Path previousPath = new Path();
+    private Path innerArea = new Path();
+    private Path temp = new Path();
+
+
     public RadarChartRenderer(RadarChart chart, ChartAnimator animator,
                               ViewPortHandler viewPortHandler) {
         super(animator, viewPortHandler);
@@ -38,6 +44,10 @@ public RadarChartRenderer(RadarChart chart, ChartAnimator animator,
         mHighlightPaint.setStrokeWidth(2f);
         mHighlightPaint.setColor(Color.rgb(255, 187, 115));
 
+        paint.setStyle(Paint.Style.FILL);
+        paint.setStrokeWidth(2f);
+        paint.setColor(Color.RED);
+
         mWebPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
         mWebPaint.setStyle(Paint.Style.STROKE);
 
@@ -282,18 +292,40 @@ protected void drawWeb(Canvas c) {
         MPPointF p1out = MPPointF.getInstance(0, 0);
         MPPointF p2out = MPPointF.getInstance(0, 0);
         for (int j = 0; j < labelCount; j++) {
-
+            if (mChart.isCustomLayerColorEnable()) {
+                innerArea.rewind();
+                paint.setColor(mChart.getLayerColorList().get(j));
+            }
             for (int i = 0; i < mChart.getData().getEntryCount(); i++) {
-
                 float r = (mChart.getYAxis().mEntries[j] - mChart.getYChartMin()) * factor;
 
                 Utils.getPosition(center, r, sliceangle * i + rotationangle, p1out);
                 Utils.getPosition(center, r, sliceangle * (i + 1) + rotationangle, p2out);
 
                 c.drawLine(p1out.x, p1out.y, p2out.x, p2out.y, mWebPaint);
+                if (mChart.isCustomLayerColorEnable()) {
+                    if (p1out.x != p2out.x) {
+                        if (i == 0) {
+                            innerArea.moveTo(p1out.x, p1out.y);
+                        } else {
+                            innerArea.lineTo(p1out.x, p1out.y);
+                        }
+                        innerArea.lineTo(p2out.x, p2out.y);
+                    }
+                }
 
 
             }
+            if (mChart.isCustomLayerColorEnable()) {
+                temp.set(innerArea);
+                if (!innerArea.isEmpty()) {
+                    boolean result = innerArea.op(previousPath, Path.Op.DIFFERENCE);
+                    if (result) {
+                        c.drawPath(innerArea, paint);
+                    }
+                }
+                previousPath.set(temp);
+            }
         }
         MPPointF.recycleInstance(p1out);
         MPPointF.recycleInstance(p2out);