fix channel image scaling with new compose

app/src/main/java/com/geeksville/mesh/ui/Channel.kt

@@ -3,20 +3,21 @@ package com.geeksville.mesh.ui
 import android.content.Intent
 import android.graphics.Bitmap
 import androidx.compose.Composable
-import androidx.ui.core.ContextAmbient
-import androidx.ui.core.Text
-import androidx.ui.foundation.SimpleImage
-import androidx.ui.graphics.Image
-import androidx.ui.graphics.ImageConfig
-import androidx.ui.graphics.NativeImage
+import androidx.ui.core.*
+import androidx.ui.foundation.Box
+import androidx.ui.graphics.*
 import androidx.ui.graphics.colorspace.ColorSpace
 import androidx.ui.graphics.colorspace.ColorSpaces
+import androidx.ui.graphics.painter.ImagePainter
 import androidx.ui.layout.*
 import androidx.ui.material.MaterialTheme
 import androidx.ui.material.OutlinedButton
 import androidx.ui.material.ripple.Ripple
 import androidx.ui.tooling.preview.Preview
+import androidx.ui.unit.Density
+import androidx.ui.unit.PxSize
 import androidx.ui.unit.dp
+import androidx.ui.unit.toRect
 import com.geeksville.analytics.DataPair
 import com.geeksville.android.GeeksvilleApplication
 import com.geeksville.android.Logging
@@ -71,6 +72,35 @@ class AndroidImage(val bitmap: Bitmap) : Image {
     }
 }
 
+
+/// Stolen from the Compose SimpleImage, replace with their real Image component someday
+// TODO(mount, malkov) : remove when RepaintBoundary is a modifier: b/149982905
+// This is class and not val because if b/149985596
+private object ClipModifier : DrawModifier {
+    override fun draw(density: Density, drawContent: () -> Unit, canvas: Canvas, size: PxSize) {
+        canvas.save()
+        canvas.clipRect(size.toRect())
+        drawContent()
+        canvas.restore()
+    }
+}
+
+/// Stolen from the Compose SimpleImage, replace with their real Image component someday
+@Composable
+fun ScaledImage(
+    image: Image,
+    modifier: Modifier = Modifier.None,
+    tint: Color? = null
+) {
+    with(DensityAmbient.current) {
+        val imageModifier = ImagePainter(image).toModifier(
+            scaleFit = ScaleFit.FillMaxDimension,
+            colorFilter = tint?.let { ColorFilter(it, BlendMode.srcIn) }
+        )
+        Box(modifier + ClipModifier + imageModifier)
+    }
+}
+
 @Composable
 fun ChannelContent(channel: Channel = Channel("Default", 7)) {
     analyticsScreen(name = "channel")
@@ -90,9 +120,10 @@ fun ChannelContent(channel: Channel = Channel("Default", 7)) {
             // val image = imageResource(id = R.drawable.qrcode)
             val image = AndroidImage(UIState.getChannelQR(context))
 
-            //Container(modifier = LayoutGravity.Center + LayoutSize.Min(200.dp, 200.dp)) {
-            SimpleImage(image = image)
-            //}
+            ScaledImage(
+                image = image,
+                modifier = LayoutGravity.Center + LayoutSize.Min(200.dp, 200.dp)
+            )
 
             Ripple(bounded = false) {
                 OutlinedButton(modifier = LayoutGravity.Center + LayoutPadding(start = 24.dp),