android/ui: improve dev QOL by adding support for compose previews

Updates corp#19117

This adds @Previews for many of the primary views.  We can expand upon this
over time to include different data sets, states, etc.

Signed-off-by: Jonathan Nobels <jonathan@tailscale.com>

android/build.gradle

@@ -126,6 +126,9 @@ dependencies {
     // Authentication only for tests
     androidTestImplementation 'dev.turingcomplete:kotlin-onetimepassword:2.4.0'
     androidTestImplementation 'commons-codec:commons-codec:1.16.1'
+    
+    debugImplementation("androidx.compose.ui:ui-tooling")
+    implementation("androidx.compose.ui:ui-tooling-preview")
 }
 
 def getLocalProperty(key) {

android/src/main/java/com/tailscale/ipn/ui/view/AboutView.kt

@@ -24,6 +24,7 @@ import androidx.compose.ui.draw.clip
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import com.tailscale.ipn.BuildConfig
 import com.tailscale.ipn.R
@@ -80,3 +81,9 @@ fun AboutView(backToSettings: BackNavigation) {
         }
   }
 }
+
+@Preview
+@Composable
+fun AboutPreview() {
+  AboutView({})
+}

android/src/main/java/com/tailscale/ipn/ui/view/BugReportView.kt

@@ -22,6 +22,7 @@ import androidx.compose.ui.text.SpanStyle
 import androidx.compose.ui.text.buildAnnotatedString
 import androidx.compose.ui.text.style.TextDecoration
 import androidx.compose.ui.text.withStyle
+import androidx.compose.ui.tooling.preview.Preview
 import androidx.lifecycle.viewmodel.compose.viewModel
 import com.tailscale.ipn.R
 import com.tailscale.ipn.ui.Links
@@ -29,6 +30,7 @@ import com.tailscale.ipn.ui.theme.defaultTextColor
 import com.tailscale.ipn.ui.theme.link
 import com.tailscale.ipn.ui.util.ClipboardValueView
 import com.tailscale.ipn.ui.util.Lists
+import com.tailscale.ipn.ui.util.set
 import com.tailscale.ipn.ui.viewModel.BugReportViewModel
 
 @Composable
@@ -81,3 +83,11 @@ fun contactText(): AnnotatedString {
   }
   return annotatedString
 }
+
+@Preview
+@Composable
+fun BugReportPreview() {
+  val vm = BugReportViewModel()
+  vm.bugReportID.set("12345678ABCDEF-12345678ABCDEF")
+  BugReportView({}, vm)
+}

android/src/main/java/com/tailscale/ipn/ui/view/DNSSettingsView.kt

@@ -17,6 +17,7 @@ import androidx.compose.runtime.collectAsState
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import androidx.lifecycle.viewmodel.compose.viewModel
 import com.tailscale.ipn.R
@@ -26,6 +27,7 @@ import com.tailscale.ipn.ui.util.ClipboardValueView
 import com.tailscale.ipn.ui.util.Lists
 import com.tailscale.ipn.ui.util.LoadingIndicator
 import com.tailscale.ipn.ui.util.itemsWithDividers
+import com.tailscale.ipn.ui.util.set
 import com.tailscale.ipn.ui.viewModel.DNSEnablementState
 import com.tailscale.ipn.ui.viewModel.DNSSettingsViewModel
 import com.tailscale.ipn.ui.viewModel.DNSSettingsViewModelFactory
@@ -99,3 +101,11 @@ fun DNSSettingsView(
     }
   }
 }
+
+@Preview
+@Composable
+fun DNSSettingsViewPreview() {
+  val vm = DNSSettingsViewModel()
+  vm.enablementState.set(DNSEnablementState.ENABLED)
+  DNSSettingsView(backToSettings = { }, vm)
+}

android/src/main/java/com/tailscale/ipn/ui/view/ErrorDialog.kt

@@ -8,7 +8,9 @@ import androidx.compose.material3.AlertDialog
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.tooling.preview.Preview
 import com.tailscale.ipn.R
+import com.tailscale.ipn.ui.theme.AppTheme
 
 
 enum class ErrorDialogType {
@@ -59,11 +61,19 @@ fun ErrorDialog(
     @StringRes buttonText: Int = R.string.ok,
     onDismiss: () -> Unit = {}
 ) {
-  AlertDialog(
+  AppTheme {
+    AlertDialog(
       onDismissRequest = onDismiss,
       title = { Text(text = stringResource(id = title)) },
       text = { Text(text = stringResource(id = message)) },
       confirmButton = {
         PrimaryActionButton(onClick = onDismiss) { Text(text = stringResource(id = buttonText)) }
       })
+  }
+}
+
+@Preview
+@Composable
+fun ErrorDialogPreview() {
+  ErrorDialog(ErrorDialogType.LOGOUT_FAILED)
 }

android/src/main/java/com/tailscale/ipn/ui/view/IntroView.kt

@@ -16,14 +16,17 @@ import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.verticalScroll
 import androidx.compose.material3.Button
 import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Surface
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import com.tailscale.ipn.R
+import com.tailscale.ipn.ui.theme.AppTheme
 
 @Composable
 fun IntroView(onContinue: () -> Unit) {
@@ -57,3 +60,9 @@ fun IntroView(onContinue: () -> Unit) {
             }
       }
 }
+
+@Composable
+@Preview
+fun IntroViewPreview() {
+  AppTheme { Surface { IntroView({}) } }
+}

android/src/main/java/com/tailscale/ipn/ui/view/LoginQRView.kt

@@ -24,10 +24,13 @@ import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.clip
 import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.window.Dialog
 import androidx.lifecycle.viewmodel.compose.viewModel
 import com.tailscale.ipn.R
+import com.tailscale.ipn.ui.theme.AppTheme
+import com.tailscale.ipn.ui.util.set
 import com.tailscale.ipn.ui.viewModel.LoginQRViewModel
 
 @OptIn(ExperimentalMaterial3Api::class)
@@ -66,3 +69,11 @@ fun LoginQRView(onDismiss: () -> Unit = {}, model: LoginQRViewModel = viewModel(
     }
   }
 }
+
+@Composable
+@Preview
+fun LoginQRViewPreview() {
+  val vm = LoginQRViewModel()
+  vm.qrCode.set(vm.generateQRCode("https://tailscale.com", 200, 0))
+  AppTheme { LoginQRView({}, vm) }
+}

android/src/main/java/com/tailscale/ipn/ui/view/MainView.kt

@@ -59,6 +59,7 @@ import androidx.compose.ui.text.buildAnnotatedString
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.text.style.TextAlign
 import androidx.compose.ui.text.style.TextOverflow
+import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import androidx.lifecycle.viewmodel.compose.viewModel
 import com.google.accompanist.permissions.ExperimentalPermissionsApi
@@ -509,3 +510,16 @@ fun PromptPermissionsIfNecessary() {
         }
   }
 }
+
+@Preview
+@Composable
+fun MainViewPreview() {
+  val vm = MainViewModel()
+  MainView(
+      {},
+      MainViewNavigation(
+          onNavigateToSettings = {},
+          onNavigateToPeerDetails = {},
+          onNavigateToExitNodes = {}),
+      vm)
+}

android/src/main/java/com/tailscale/ipn/ui/view/ManagedByView.kt

@@ -16,6 +16,7 @@ import androidx.compose.runtime.collectAsState
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import androidx.lifecycle.viewmodel.compose.viewModel
 import com.tailscale.ipn.R
@@ -46,3 +47,10 @@ fun ManagedByView(backToSettings: BackNavigation, model: IpnViewModel = viewMode
         }
   }
 }
+
+@Preview
+@Composable
+fun ManagedByViewPreview() {
+  val vm = IpnViewModel()
+  ManagedByView(backToSettings = {}, vm)
+}

android/src/main/java/com/tailscale/ipn/ui/view/SettingsView.kt

@@ -22,6 +22,7 @@ import androidx.compose.ui.text.SpanStyle
 import androidx.compose.ui.text.buildAnnotatedString
 import androidx.compose.ui.text.style.TextDecoration
 import androidx.compose.ui.text.withStyle
+import androidx.compose.ui.tooling.preview.Preview
 import androidx.lifecycle.viewmodel.compose.viewModel
 import com.tailscale.ipn.BuildConfig
 import com.tailscale.ipn.R
@@ -29,6 +30,7 @@ import com.tailscale.ipn.ui.Links
 import com.tailscale.ipn.ui.theme.link
 import com.tailscale.ipn.ui.theme.listItem
 import com.tailscale.ipn.ui.util.Lists
+import com.tailscale.ipn.ui.util.set
 import com.tailscale.ipn.ui.viewModel.SettingsNav
 import com.tailscale.ipn.ui.viewModel.SettingsViewModel
 
@@ -177,3 +179,14 @@ fun AdminTextView(onNavigateToAdminConsole: () -> Unit) {
 
   Lists.InfoItem(adminStr, onClick = onNavigateToAdminConsole)
 }
+
+@Preview
+@Composable
+fun SettingsPreview() {
+  val vm = SettingsViewModel()
+  vm.corpDNSEnabled.set(true)
+  vm.tailNetLockEnabled.set(true)
+  vm.isAdmin.set(true)
+  vm.managedByOrganization.set("Tails and Scales Inc.")
+  SettingsView(SettingsNav({}, {}, {}, {}, {}, {}, {}, {}, {}, {}), vm)
+}

android/src/main/java/com/tailscale/ipn/ui/view/TailnetLockSetupView.kt

@@ -23,6 +23,7 @@ import androidx.compose.ui.text.SpanStyle
 import androidx.compose.ui.text.buildAnnotatedString
 import androidx.compose.ui.text.style.TextDecoration
 import androidx.compose.ui.text.withStyle
+import androidx.compose.ui.tooling.preview.Preview
 import androidx.lifecycle.viewmodel.compose.viewModel
 import com.tailscale.ipn.R
 import com.tailscale.ipn.ui.Links
@@ -31,6 +32,7 @@ import com.tailscale.ipn.ui.theme.link
 import com.tailscale.ipn.ui.util.ClipboardValueView
 import com.tailscale.ipn.ui.util.Lists
 import com.tailscale.ipn.ui.util.LoadingIndicator
+import com.tailscale.ipn.ui.util.set
 import com.tailscale.ipn.ui.viewModel.TailnetLockSetupViewModel
 import com.tailscale.ipn.ui.viewModel.TailnetLockSetupViewModelFactory
 
@@ -115,3 +117,12 @@ fun explainerText(): AnnotatedString {
   }
   return annotatedString
 }
+
+@Composable
+@Preview
+fun TailnetLockSetupViewPreview() {
+  val vm = TailnetLockSetupViewModel()
+  vm.nodeKey.set("8BADF00D-EA7-1337-DEAD-BEEF")
+  vm.tailnetLockKey.set("C0FFEE-CAFE-50DA")
+  TailnetLockSetupView(backToSettings = {}, vm)
+}

android/src/main/java/com/tailscale/ipn/ui/view/UserSwitcherView.kt

@@ -32,6 +32,7 @@ import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import androidx.lifecycle.viewmodel.compose.viewModel
 import com.tailscale.ipn.R
@@ -189,3 +190,10 @@ fun FusMenu(viewModel: UserSwitcherViewModel) {
             })
       }
 }
+
+@Composable
+@Preview
+fun UserSwitcherViewPreview() {
+  val vm = UserSwitcherViewModel()
+  UserSwitcherView(backToSettings = {}, onNavigateHome = {}, vm)
+}