feat: add dialog to handle WiFi Credential QR code scan errors

app/src/main/java/com/geeksville/mesh/ui/components/SimpleAlertDialog.kt

@@ -0,0 +1,75 @@
+package com.geeksville.mesh.ui.components
+
+import androidx.annotation.StringRes
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.shape.RoundedCornerShape
+import androidx.compose.material.AlertDialog
+import androidx.compose.material.ButtonDefaults
+import androidx.compose.material.MaterialTheme
+import androidx.compose.material.Text
+import androidx.compose.material.TextButton
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.tooling.preview.PreviewLightDark
+import androidx.compose.ui.unit.dp
+import com.geeksville.mesh.R
+import com.geeksville.mesh.ui.theme.AppTheme
+
+@Composable
+fun SimpleAlertDialog(
+    @StringRes title: Int,
+    text: @Composable (() -> Unit)? = null,
+    onDismiss: () -> Unit = {},
+) = AlertDialog(
+    onDismissRequest = onDismiss,
+    confirmButton = {
+        TextButton(
+            onClick = onDismiss,
+            modifier = Modifier
+                .padding(horizontal = 16.dp),
+            colors =  ButtonDefaults.textButtonColors(
+                contentColor = MaterialTheme.colors.onSurface,
+            ),
+        ) { Text(text = stringResource(id = R.string.close)) }
+    },
+    title = {
+        Text(
+            text = stringResource(id = title),
+            modifier = Modifier.fillMaxWidth(),
+            textAlign = TextAlign.Center,
+        )
+    },
+    text = text,
+    shape = RoundedCornerShape(16.dp),
+)
+
+@Composable
+fun SimpleAlertDialog(
+    @StringRes title: Int,
+    @StringRes text: Int,
+    onDismiss: () -> Unit = {},
+) = SimpleAlertDialog(
+    onDismiss = onDismiss,
+    title = title,
+    text = {
+        Text(
+            text = stringResource(id = text),
+            modifier = Modifier.fillMaxWidth(),
+            textAlign = TextAlign.Center,
+        )
+    },
+)
+
+@PreviewLightDark
+@Composable
+private fun SimpleAlertDialogPreview() {
+    AppTheme {
+        SimpleAlertDialog(
+            title = R.string.message,
+            text = R.string.sample_message,
+        )
+    }
+}

app/src/main/java/com/geeksville/mesh/ui/components/config/NetworkConfigItemList.kt

@@ -23,6 +23,7 @@ import androidx.compose.ui.text.input.KeyboardType
 import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import com.geeksville.mesh.ConfigProtos.Config.NetworkConfig
+import com.geeksville.mesh.R
 import com.geeksville.mesh.copy
 import com.geeksville.mesh.ui.components.DropDownPreference
 import com.geeksville.mesh.ui.components.EditIPv4Preference
@@ -30,10 +31,20 @@ import com.geeksville.mesh.ui.components.EditPasswordPreference
 import com.geeksville.mesh.ui.components.EditTextPreference
 import com.geeksville.mesh.ui.components.PreferenceCategory
 import com.geeksville.mesh.ui.components.PreferenceFooter
+import com.geeksville.mesh.ui.components.SimpleAlertDialog
 import com.geeksville.mesh.ui.components.SwitchPreference
 import com.journeyapps.barcodescanner.ScanContract
 import com.journeyapps.barcodescanner.ScanOptions
 
+@Composable
+private fun ScanErrorDialog(
+    onDismiss: () -> Unit = {}
+) = SimpleAlertDialog(
+    title = R.string.error,
+    text = R.string.wifi_qr_code_error,
+    onDismiss = onDismiss,
+)
+
 @Composable
 fun NetworkConfigItemList(
     networkConfig: NetworkConfig,
@@ -43,6 +54,11 @@ fun NetworkConfigItemList(
     val focusManager = LocalFocusManager.current
     var networkInput by rememberSaveable { mutableStateOf(networkConfig) }
 
+    var showScanErrorDialog: Boolean by rememberSaveable { mutableStateOf(false) }
+    if (showScanErrorDialog) {
+        ScanErrorDialog { showScanErrorDialog = false }
+    }
+
     fun extractWifiCredentials(qrCode: String) = Regex("""WIFI:S:(.*?);.*?P:(.*?);""")
         .find(qrCode)?.destructured
         ?.let { (ssid, password) -> ssid to password }
@@ -55,7 +71,7 @@ fun NetworkConfigItemList(
                 networkInput = networkInput.copy { wifiSsid = ssid }
                 networkInput = networkInput.copy { wifiPsk = psk }
             } else {
-                // TODO show: "Invalid WiFi Credential QR code format"
+                showScanErrorDialog = true
             }
         }
     }
@@ -237,3 +253,9 @@ private fun NetworkConfigPreview() {
         onSaveClicked = { },
     )
 }
+
+@Preview(showBackground = true)
+@Composable
+private fun QrCodeErrorDialogPreview() {
+    ScanErrorDialog()
+}

app/src/main/res/values/strings.xml

@@ -212,4 +212,6 @@
         <item quantity="other">Do you want to add %d new channels?</item>
     </plurals>
     <string name="replace">Replace</string>
+    <string name="wifi_qr_code_scan">Scan WiFi QR code</string>
+    <string name="wifi_qr_code_error">Invalid WiFi Credential QR code format</string>
 </resources>