add gradient rotation demo

app/src/main/java/com/smarttoolfactory/composecolorsextended/MainActivity.kt

@@ -17,6 +17,7 @@ import com.google.accompanist.pager.HorizontalPager
 import com.google.accompanist.pager.PagerState
 import com.google.accompanist.pager.rememberPagerState
 import com.google.accompanist.systemuicontroller.rememberSystemUiController
+import com.smarttoolfactory.composecolorsextended.demo.GradientAngleDemo
 import com.smarttoolfactory.composecolorsextended.demo.MD2ColorSelectionDemo
 import com.smarttoolfactory.composecolorsextended.demo.MD3ColorShadeSelectionDemo
 import com.smarttoolfactory.composecolorsextended.ui.theme.ComposeColorsExtendedTheme
@@ -94,9 +95,10 @@ private fun HomeContent() {
  0 -> MD2ColorSelectionDemo {
  backgroundColor = it
  }
- else -> MD3ColorShadeSelectionDemo {
+ 1 -> MD3ColorShadeSelectionDemo {
  backgroundColor = it
  }
+ else -> GradientAngleDemo()
  }
  }
 }

app/src/main/java/com/smarttoolfactory/composecolorsextended/demo/GradientAngleDemo.kt

@@ -0,0 +1,138 @@
+package com.smarttoolfactory.composecolorsextended.demo
+
+import androidx.compose.foundation.Canvas
+import androidx.compose.foundation.layout.*
+import androidx.compose.material.Slider
+import androidx.compose.material.Text
+import androidx.compose.runtime.*
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Brush
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.drawscope.DrawScope
+import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.sp
+import com.smarttoolfactory.extendedcolors.GradientAngle
+import com.smarttoolfactory.extendedcolors.GradientOffset
+import com.smarttoolfactory.extendedcolors.MaterialColor.Blue400
+import kotlin.math.roundToInt
+
+/**
+ * Demo for creating gradients for different type of pickers or sliders
+ */
+@Composable
+fun GradientAngleDemo() {
+
+ val canvasModifier = Modifier.size(300.dp)
+
+ // Offsets for gradients based on selected angle
+ var gradientOffset by remember {
+ mutableStateOf(GradientOffset(GradientAngle.CW0))
+ }
+
+ var angleSelection by remember { mutableStateOf(0f) }
+ var angleText by remember { mutableStateOf("0 Degrees") }
+
+
+
+ Column(
+ modifier = Modifier
+ .fillMaxSize()
+ .padding(8.dp),
+ horizontalAlignment = Alignment.CenterHorizontally
+ ) {
+
+ Text(
+ text = angleText,
+ color = Blue400,
+ modifier = Modifier
+ .padding(8.dp),
+ fontSize = 18.sp,
+ fontWeight = FontWeight.Bold
+ )
+
+ Slider(
+ modifier = Modifier.height(50.dp),
+ value = angleSelection,
+ onValueChange = {
+ angleSelection = it
+
+ gradientOffset = when (angleSelection.roundToInt()) {
+ 0 -> {
+ angleText = "0 Degrees"
+ GradientOffset(GradientAngle.CW0)
+ }
+ 1 -> {
+ angleText = "45 Degrees"
+ GradientOffset(GradientAngle.CW45)
+ }
+ 2 -> {
+ angleText = "90 Degrees"
+ GradientOffset(GradientAngle.CW90)
+ }
+ 3 -> {
+ angleText = "135 Degrees"
+ GradientOffset(GradientAngle.CW135)
+ }
+ 4 -> {
+ angleText = "180 Degrees"
+ GradientOffset(GradientAngle.CW180)
+ }
+
+ 5 -> {
+ angleText = "225 Degrees"
+ GradientOffset(GradientAngle.CW225)
+ }
+ 6 -> {
+ angleText = "270 Degrees"
+ GradientOffset(GradientAngle.CW270)
+ }
+ else -> {
+ angleText = "315 Degrees"
+ GradientOffset(GradientAngle.CW315)
+ }
+ }
+ },
+ steps = 6,
+ valueRange = 0f..7f
+ )
+
+ CanvasWithTitle(
+ modifier = canvasModifier,
+ text = "Gradient Angle"
+ ) {
+ val redGreenGradient = Brush.linearGradient(
+ colors = listOf(Color.Red, Color.Green, Color.Blue),
+ start = gradientOffset.start,
+ end = gradientOffset.end
+ )
+ drawRect(redGreenGradient)
+ }
+
+ }
+}
+
+@Composable
+private fun CanvasWithTitle(
+ modifier: Modifier = Modifier,
+ text: String,
+ onDraw: DrawScope.() -> Unit
+) {
+ Column(
+ modifier = Modifier
+ .wrapContentWidth()
+ ) {
+
+ Text(
+ text = text,
+ color = Blue400,
+ modifier = Modifier
+ .padding(8.dp),
+ fontSize = 18.sp,
+ fontWeight = FontWeight.Bold
+ )
+
+ Canvas(modifier = modifier, onDraw = onDraw)
+ }
+}