channel qrs are now sharable and real

TODO.md

@@ -9,8 +9,6 @@ Work items for soon alpha builds
 * fix app icon in title bar
 * show direction on the nodeinfo cards
 * take video of the app
-* make channel button look like a button
-* generate real channel QR codes
 * register app link for our URLs https://developer.android.com/studio/write/app-link-indexing.html
 * let users change & share channels (but no saving them yet)
 * treat macaddrs as the unique id, not the app layer user id
@@ -160,3 +158,5 @@ Don't leave device discoverable.  Don't let unpaired users do things with device
 * have notification (individually maskable) notifications for received texts - use file:///home/kevinh/packages/android-sdk-linux/docs/reference/android/support/v4/app/NotificationCompat.BigTextStyle.html
 * startforegroundservice only if we have a valid radio
 * when we select a new radio, restart the service
+* make channel button look like a button
+* generate real channel QR codes

app/src/main/java/com/geeksville/mesh/MainActivity.kt

@@ -179,7 +179,7 @@ class MainActivity : AppCompatActivity(), Logging,
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
 
-        val prefs = getSharedPreferences("ui-prefs", Context.MODE_PRIVATE)
+        val prefs = UIState.getPreferences(this)
         UIState.ownerName = prefs.getString("owner", "")!!
         UIState.meshService = null
 
@@ -276,9 +276,9 @@ class MainActivity : AppCompatActivity(), Logging,
         val bytes = UIState.meshService!!.radioConfig
 
         val config = MeshProtos.RadioConfig.parseFrom(bytes)
-        UIState.radioConfig.value = config
+        UIState.setRadioConfig(this, config)
 
-        debug("Read config from radio, channel URL ${UIState.channelUrl}")
+        debug("Read config from radio")
     }
 
     /// Called when we gain/lose a connection to our mesh radio

app/src/main/java/com/geeksville/mesh/model/UIState.kt

@@ -1,6 +1,7 @@
 package com.geeksville.mesh.model
 
 import android.content.Context
+import android.content.SharedPreferences
 import android.graphics.Bitmap
 import android.os.RemoteException
 import android.util.Base64
@@ -26,7 +27,7 @@ object UIState : Logging {
     val isConnected = mutableStateOf(false)
 
     /// various radio settings (including the channel)
-    val radioConfig = mutableStateOf(MeshProtos.RadioConfig.getDefaultInstance())
+    private val radioConfig = mutableStateOf<MeshProtos.RadioConfig?>(null)
 
     /// our name in hte radio
     /// Note, we generate owner initials automatically for now
@@ -34,22 +35,44 @@ object UIState : Logging {
     var ownerName: String = "MrInIDE Ownername"
 
     /// Return an URL that represents the current channel values
-    val channelUrl
-        get(): String {
-            val channelBytes = radioConfig.value.channelSettings.toByteArray()
+    fun getChannelUrl(context: Context): String {
+        // If we have a valid radio config use it, othterwise use whatever we have saved in the prefs
+        val radio = radioConfig.value
+        if (radio != null) {
+            val settings = radio.channelSettings
+            val channelBytes = settings.toByteArray()
             val enc = Base64.encodeToString(channelBytes, Base64.URL_SAFE + Base64.NO_WRAP)
 
             return "https://www.meshtastic.org/c/$enc"
+        } else {
+            return getPreferences(context).getString(
+                "owner",
+                "https://www.meshtastic.org/c/unset"
+            )!!
         }
+    }
 
-    val channelQR
-        get(): Bitmap {
-            val multiFormatWriter = MultiFormatWriter()
+    fun getChannelQR(context: Context): Bitmap
+    {
+        val multiFormatWriter = MultiFormatWriter()
 
-            val bitMatrix = multiFormatWriter.encode(channelUrl, BarcodeFormat.QR_CODE, 192, 192);
-            val barcodeEncoder = BarcodeEncoder()
-            return barcodeEncoder.createBitmap(bitMatrix)
+        val bitMatrix =
+            multiFormatWriter.encode(getChannelUrl(context), BarcodeFormat.QR_CODE, 192, 192);
+        val barcodeEncoder = BarcodeEncoder()
+        return barcodeEncoder.createBitmap(bitMatrix)
+    }
+
+    fun getPreferences(context: Context): SharedPreferences =
+        context.getSharedPreferences("ui-prefs", Context.MODE_PRIVATE)
+
+    /// Set the radio config (also updates our saved copy in preferences)
+    fun setRadioConfig(context: Context, c: MeshProtos.RadioConfig) {
+        radioConfig.value = c
+
+        getPreferences(context).edit(commit = true) {
+            this.putString("channel-url", getChannelUrl(context))
         }
+    }
 
     // clean up all this nasty owner state management FIXME
     fun setOwner(context: Context, s: String? = null) {
@@ -58,8 +81,7 @@ object UIState : Logging {
             ownerName = s
 
             // note: we allow an empty userstring to be written to prefs
-            val prefs = context.getSharedPreferences("ui-prefs", Context.MODE_PRIVATE)
-            prefs.edit(commit = true) {
+            getPreferences(context).edit(commit = true) {
                 putString("owner", s)
             }
         }

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

@@ -1,27 +1,24 @@
 package com.geeksville.mesh.ui
 
+import android.content.Intent
 import android.graphics.Bitmap
-import android.os.Build
 import androidx.compose.Composable
-import androidx.compose.ambient
 import androidx.ui.core.ContextAmbient
 import androidx.ui.core.Text
-import androidx.ui.foundation.Clickable
 import androidx.ui.foundation.DrawImage
-import androidx.ui.graphics.*
+import androidx.ui.graphics.Image
+import androidx.ui.graphics.ImageConfig
+import androidx.ui.graphics.NativeImage
 import androidx.ui.graphics.colorspace.ColorSpace
 import androidx.ui.graphics.colorspace.ColorSpaces
 import androidx.ui.layout.*
-import androidx.ui.material.Button
 import androidx.ui.material.MaterialTheme
 import androidx.ui.material.OutlinedButton
 import androidx.ui.material.ripple.Ripple
-import androidx.ui.res.imageResource
 import androidx.ui.tooling.preview.Preview
 import androidx.ui.unit.dp
 import com.geeksville.android.GeeksvilleApplication
 import com.geeksville.android.Logging
-import com.geeksville.android.toast
 import com.geeksville.mesh.R
 import com.geeksville.mesh.model.UIState
 
@@ -88,7 +85,7 @@ fun ChannelContent(channel: Channel = Channel("Default", 7)) {
         Row(modifier = LayoutGravity.Center) {
             // simulated qr code
             // val image = imageResource(id = R.drawable.qrcode)
-            val image = AndroidImage(UIState.channelQR)
+            val image = AndroidImage(UIState.getChannelQR(context))
 
             Container(modifier = LayoutGravity.Center + LayoutSize.Min(200.dp, 200.dp)) {
                 DrawImage(image = image)
@@ -97,9 +94,18 @@ fun ChannelContent(channel: Channel = Channel("Default", 7)) {
             Ripple(bounded = false) {
                 OutlinedButton(modifier = LayoutGravity.Center + LayoutPadding(left = 24.dp),
                     onClick = {
-                    GeeksvilleApplication.analytics.track("channel_share") // track how many times users share channels
-                    context.toast("Channel sharing is not yet implemented")
-                }) {
+                        GeeksvilleApplication.analytics.track("channel_share") // track how many times users share channels
+
+                        val sendIntent: Intent = Intent().apply {
+                            action = Intent.ACTION_SEND
+                            putExtra(Intent.EXTRA_TEXT, UIState.getChannelUrl(context))
+                            putExtra(Intent.EXTRA_TITLE, "A URL for joining a Meshtastic mesh")
+                            type = "text/plain"
+                        }
+
+                        val shareIntent = Intent.createChooser(sendIntent, null)
+                        context.startActivity(shareIntent)
+                    }) {
                     VectorImage(
                         id = R.drawable.ic_twotone_share_24,
                         tint = palette.onBackground