Optional hatch fill

Author: hannesa2

app/src/main/kotlin/info/appdev/chartexample/TimeIntervalChartActivity.kt

@@ -29,7 +29,7 @@ class TimeIntervalChartActivity : DemoBase(), OnChartValueSelectedListener {
         // Add sample project tasks
         ganttData.addTask(GanttTask("Design", 0f, 50f, Color.rgb(255, 107, 107))) // Red: 0-50
         ganttData.addTask(GanttTask("Dev", 40f, 100f, Color.rgb(66, 165, 245))) // Blue: 40-140
-        ganttData.addTask(GanttTask("Testing", 120f, 40f, Color.rgb(76, 175, 80))) // Green: 120-160
+        ganttData.addTask(GanttTask("Testing", 120f, 40f, Color.rgb(76, 175, 80), hatched = true)) // Green: 120-160
         ganttData.addTask(GanttTask("Launch", 150f, 20f, Color.rgb(255, 193, 7))) // Yellow: 150-170
 
         // Set data and render

chartLib/src/main/kotlin/info/appdev/charting/charts/GanttChart.kt

@@ -8,10 +8,12 @@ import android.util.AttributeSet
 import android.view.View
 import info.appdev.charting.data.GanttChartData
 import java.util.Locale
+import androidx.core.graphics.withClip
 
 class GanttChart : View {
     private var data: GanttChartData? = null
     private var taskPaint: Paint? = null
+    private var hatchPaint: Paint? = null
     private var gridPaint: Paint? = null
     private var textPaint: Paint? = null
 
@@ -40,6 +42,12 @@ class GanttChart : View {
         taskPaint = Paint().apply {
             isAntiAlias = true
         }
+        hatchPaint = Paint().apply {
+            color = 0x7DFFFFFF   // more transparent (0x7D ≈ 66 % opacity vs previous 0x55 ≈ 33 %)
+            strokeWidth = 20f     // thicker lines (was 2f)
+            isAntiAlias = true
+            style = Paint.Style.STROKE
+        }
         gridPaint = Paint().apply {
             color = -0x333334
             strokeWidth = 1f
@@ -179,6 +187,18 @@ class GanttChart : View {
             val rect = RectF(startX, taskY, endX, taskY + taskHeight)
             taskPaint!!.color = task.color
             canvas.drawRect(rect, taskPaint!!)
+
+            if (task.hatched) {
+                // Hatch lines (45° diagonal, bottom-left → top-right)
+                canvas.withClip(rect) {
+                    val hatchSpacing = 10f
+                    var hx = startX - taskHeight
+                    while (hx < endX + taskHeight) {
+                        drawLine(hx, taskY + taskHeight, hx + taskHeight, taskY, hatchPaint!!)
+                        hx += hatchSpacing
+                    }
+                }
+            }
             canvas.drawRect(rect, borderPaint)
         }
     }

chartLib/src/main/kotlin/info/appdev/charting/data/GanttTask.kt

@@ -9,7 +9,7 @@ package info.appdev.charting.data
  * @param duration How long the task lasts
  * @param color Display color (Android color int)
  */
-class GanttTask(val name: String?, val startTime: Float, val duration: Float, val color: Int) {
+class GanttTask(val name: String?, val startTime: Float, val duration: Float, val color: Int, val hatched: Boolean = false) {
     val endTime: Float
         get() = startTime + duration
 }