UI changes: can go back in edition view

composeApp/src/desktopMain/kotlin/com/jaytux/grader/ui/Assignments.kt

@@ -20,8 +20,6 @@ import com.mohamedrejeb.richeditor.ui.material3.OutlinedRichTextEditor
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
 fun GroupAssignmentView(state: GroupAssignmentState) {
-    val (course, edition) = state.editionCourse
-    val name by state.name
     val task by state.task
     val deadline by state.deadline
     val allFeedback by state.feedback.entities
@@ -29,7 +27,6 @@ fun GroupAssignmentView(state: GroupAssignmentState) {
     var idx by remember(state) { mutableStateOf(0) }
 
     Column(Modifier.padding(10.dp)) {
-        PaneHeader(name, "group assignment", course, edition)
         if(allFeedback.any { it.second.feedback == null }) {
             Text("Groups in bold have no feedback yet.", fontStyle = FontStyle.Italic)
         }
@@ -150,8 +147,6 @@ fun groupFeedback(state: GroupAssignmentState, fdbk: GroupAssignmentState.LocalG
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
 fun SoloAssignmentView(state: SoloAssignmentState) {
-    val name by state.name
-    val (course, edition) = state.editionCourse
     val task by state.task
     val deadline by state.deadline
     val suggestions by state.autofill.entities
@@ -160,7 +155,6 @@ fun SoloAssignmentView(state: SoloAssignmentState) {
     var idx by remember(state) { mutableStateOf(0) }
 
     Column(Modifier.padding(10.dp)) {
-        PaneHeader(name, "individual assignment", course, edition)
         Row {
             Surface(Modifier.weight(0.25f), tonalElevation = 10.dp) {
                 LazyColumn(Modifier.fillMaxHeight().padding(10.dp)) {

composeApp/src/desktopMain/kotlin/com/jaytux/grader/ui/Editions.kt

@@ -15,10 +15,6 @@ import androidx.compose.ui.window.*
 import com.jaytux.grader.data.*
 import com.jaytux.grader.viewmodel.*
 
-enum class OpenPanel(val tabName: String) {
-    Student("Students"), Group("Groups"), Assignment("Assignments")
-}
-
 data class Navigators(
     val student: (Student) -> Unit,
     val group: (Group) -> Unit,
@@ -36,41 +32,41 @@ fun EditionView(state: EditionState) = Row(Modifier.padding(0.dp)) {
     val mergedAssignments by remember(solo, groupAs) {
         mutableStateOf(Assignment.merge(groupAs, solo))
     }
-    var selected by remember { mutableStateOf(-1) }
-    var tab by remember { mutableStateOf(OpenPanel.Assignment) }
+    val hist by state.history
 
     val navs = Navigators(
-        student = { tab = OpenPanel.Student; selected = students.indexOfFirst { s -> s.id == it.id } },
-        group = { tab = OpenPanel.Group; selected = groups.indexOfFirst { g -> g.id == it.id } },
-        assignment = { tab = OpenPanel.Assignment; selected = mergedAssignments.indexOfFirst { a -> a.id() == it.id() } }
+        student = { state.navTo(OpenPanel.Student, students.indexOfFirst{ s -> s.id == it.id }) },
+        group = { state.navTo(OpenPanel.Group, groups.indexOfFirst { g -> g.id == it.id }) },
+        assignment = { state.navTo(OpenPanel.Assignment, mergedAssignments.indexOfFirst { a -> a.id() == it.id() }) }
     )
 
+    val (id, tab) = hist.last()
     Surface(Modifier.weight(0.25f), tonalElevation = 5.dp) {
         TabLayout(
             OpenPanel.entries,
             tab.ordinal,
-            { tab = OpenPanel.entries[it]; selected = -1 },
+            { state.navTo(OpenPanel.entries[it]) },
             { Text(it.tabName) }
         ) {
             when(tab) {
                 OpenPanel.Student -> StudentPanel(
-                    course, edition, students, availableStudents, selected,
-                    { selected = it },
+                    course, edition, students, availableStudents, id,
+                    { state.navTo(it) },
                     { name, note, contact, add -> state.newStudent(name, contact, note, add) },
                     { students -> state.addToCourse(students) },
                     { s, name -> state.setStudentName(s, name) }
                 ) { s -> state.delete(s) }
 
                 OpenPanel.Group -> GroupPanel(
-                    course, edition, groups, selected,
-                    { selected = it },
+                    course, edition, groups, id,
+                    { state.navTo(it) },
                     { name -> state.newGroup(name) },
                     { g, name -> state.setGroupName(g, name) }
                 ) { g -> state.delete(g) }
 
                 OpenPanel.Assignment -> AssignmentPanel(
-                    course, edition, mergedAssignments, selected,
-                    { selected = it },
+                    course, edition, mergedAssignments, id,
+                    { state.navTo(it) },
                     { type, name -> state.newAssignment(type, name) },
                     { a, name -> state.setAssignmentTitle(a, name) }
                 ) { a -> state.delete(a) }
@@ -78,13 +74,33 @@ fun EditionView(state: EditionState) = Row(Modifier.padding(0.dp)) {
         }
     }
 
-    Box(Modifier.weight(0.75f)) {
-        if(selected != -1) {
+    Column(Modifier.weight(0.75f)) {
+        Row {
+            IconButton({ state.back() }, enabled = hist.size >= 2) {
+                Icon(ChevronLeft, "Back", Modifier.size(MaterialTheme.typography.headlineMedium.fontSize.toDp()).align(Alignment.CenterVertically))
+            }
             when(tab) {
-                OpenPanel.Student -> StudentView(StudentState(students[selected], edition), navs)
-                OpenPanel.Group -> GroupView(GroupState(groups[selected]), navs)
+                OpenPanel.Student -> {
+                    if(id == -1) PaneHeader("Nothing selected", "students", course, edition)
+                    else PaneHeader(students[id].name, "student", course, edition)
+                }
+                OpenPanel.Group -> {
+                    if(id == -1) PaneHeader("Nothing selected", "groups", course, edition)
+                    else PaneHeader(groups[id].name, "group", course, edition)
+                }
                 OpenPanel.Assignment -> {
-                    when(val a = mergedAssignments[selected]) {
+                    if(id == -1) PaneHeader("Nothing selected", "assignments", course, edition)
+                    else PaneHeader(mergedAssignments[id].name(), "assignment", course, edition)
+                }
+            }
+        }
+        Box(Modifier.weight(1f)) {
+            if (id != -1) {
+                when (tab) {
+                    OpenPanel.Student -> StudentView(StudentState(students[id], edition), navs)
+                    OpenPanel.Group -> GroupView(GroupState(groups[id]), navs)
+                    OpenPanel.Assignment -> {
+                        when (val a = mergedAssignments[id]) {
                             is Assignment.SAssignment -> SoloAssignmentView(SoloAssignmentState(a.assignment))
                             is Assignment.GAssignment -> GroupAssignmentView(GroupAssignmentState(a.assignment))
                         }
@@ -93,6 +109,7 @@ fun EditionView(state: EditionState) = Row(Modifier.padding(0.dp)) {
             }
         }
     }
+}
 
 @Composable
 fun StudentPanel(

composeApp/src/desktopMain/kotlin/com/jaytux/grader/ui/Views.kt

@@ -17,8 +17,6 @@ import androidx.compose.ui.unit.dp
 import androidx.compose.ui.window.DialogWindow
 import androidx.compose.ui.window.WindowPosition
 import androidx.compose.ui.window.rememberDialogState
-import com.jaytux.grader.data.Group
-import com.jaytux.grader.data.Student
 import com.jaytux.grader.maxN
 import com.jaytux.grader.viewmodel.GroupState
 import com.jaytux.grader.viewmodel.StudentState
@@ -31,7 +29,6 @@ fun StudentView(state: StudentState, nav: Navigators) {
     val soloGrades by state.soloGrades.entities
 
     Column(Modifier.padding(10.dp)) {
-        PaneHeader(state.student.name, "student", state.editionCourse)
         Row {
             Column(Modifier.weight(0.45f)) {
                 Column(Modifier.padding(10.dp).weight(0.35f)) {
@@ -150,12 +147,10 @@ fun GroupView(state: GroupState, nav: Navigators) {
     val members by state.members.entities
     val available by state.availableStudents.entities
     val allRoles by state.roles.entities
-    val (course, edition) = state.course
 
     var pickRole: Pair<String?, (String?) -> Unit>? by remember { mutableStateOf(null) }
 
     Column(Modifier.padding(10.dp)) {
-        PaneHeader(state.group.name, "group", course, edition)
         Row {
             Column(Modifier.weight(0.5f)) {
                 Text("Students", style = MaterialTheme.typography.headlineSmall)

composeApp/src/desktopMain/kotlin/com/jaytux/grader/viewmodel/DbState.kt

@@ -87,12 +87,18 @@ class EditionListState(val course: Course) {
     }
 }
 
+enum class OpenPanel(val tabName: String) {
+    Student("Students"), Group("Groups"), Assignment("Assignments")
+}
+
 class EditionState(val edition: Edition) {
     val course = transaction { edition.course }
     val students = RawDbState { edition.soloStudents.sortAsc(Students.name).toList() }
     val groups = RawDbState { edition.groups.sortAsc(Groups.name).toList() }
     val solo = RawDbState { edition.soloAssignments.sortAsc(SoloAssignments.name).toList() }
     val groupAs = RawDbState { edition.groupAssignments.sortAsc(GroupAssignments.name).toList() }
+    private val _history = mutableStateOf(listOf(-1 to OpenPanel.Assignment))
+    val history = _history.immutable()
 
     val availableStudents = RawDbState {
         Student.find {
@@ -217,6 +223,16 @@ class EditionState(val edition: Edition) {
         is Assignment.GAssignment -> delete(assignment.assignment)
         is Assignment.SAssignment -> delete(assignment.assignment)
     }
+
+    fun navTo(panel: OpenPanel, id: Int = -1) {
+        _history.value += (id to panel)
+    }
+    fun navTo(id: Int) = navTo(_history.value.last().second, id)
+    fun back() {
+        var temp = _history.value.dropLast(1)
+        while(temp.last().first == -1 && temp.size >= 2) temp = temp.dropLast(1)
+        _history.value = temp
+    }
 }
 
 class StudentState(val student: Student, edition: Edition) {