Add DSB Zoom

Minor changes PSE

app/src/main/java/com/schoolapp/cleverclass/DSBDayViewActivity.kt

@@ -5,6 +5,7 @@ import android.os.Bundle
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
 import androidx.compose.foundation.Image
+import androidx.compose.foundation.gestures.detectTransformGestures
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.fillMaxSize
@@ -12,8 +13,7 @@ import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
-import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.lazy.LazyColumn
-import androidx.compose.foundation.verticalScroll
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.ArrowBack
 import androidx.compose.material3.ExperimentalMaterial3Api
@@ -25,13 +25,22 @@ import androidx.compose.material3.Text
 import androidx.compose.material3.TopAppBar
 import androidx.compose.material3.TopAppBarDefaults
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.graphics.asImageBitmap
+import androidx.compose.ui.graphics.graphicsLayer
+import androidx.compose.ui.input.pointer.pointerInput
 import androidx.compose.ui.layout.ContentScale
 import androidx.compose.ui.unit.dp
+import androidx.compose.ui.zIndex
 import com.schoolapp.cleverclass.ui.theme.CleverClassTheme
 import org.json.JSONObject
 import java.io.File
+import java.lang.Float.max
+import java.lang.Float.min
 
 private lateinit var folder : File
 private lateinit var information : JSONObject
@@ -64,6 +73,10 @@ class DSBDayViewActivity : ComponentActivity() {
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
 fun DSBDayViewContent(activity: ComponentActivity){
+    var scale by remember { mutableStateOf(1f) }
+    var XOffset by remember { mutableStateOf(0f) }
+    var YOffset by remember { mutableStateOf(0f) }
+
     Column{
         TopAppBar(
             colors = TopAppBarDefaults.centerAlignedTopAppBarColors(MaterialTheme.colorScheme.primaryContainer),
@@ -83,17 +96,35 @@ fun DSBDayViewContent(activity: ComponentActivity){
                     )
                 }
             },
-            modifier = Modifier.fillMaxWidth()
+            modifier = Modifier
+                .fillMaxWidth()
+                .zIndex(1f)
         )
 
         val imageFiles = folder.listFiles { file -> file.extension == "jpg" }?.toList()
 
-        Column(
+        LazyColumn(
+            userScrollEnabled = true,
             modifier = Modifier
                 .padding(8.dp)
-                .verticalScroll(rememberScrollState())
+                .pointerInput(Unit) {
+                    detectTransformGestures { _, move, zoom, _ ->
+                        scale = max(min(zoom * scale, 2f), 1f)
+                        val maxXOffset = 520 * (scale - 1)
+                        val maxYOffset = 992 * (scale - 1)
+                        XOffset = max(min(XOffset + move.x, maxXOffset), -maxXOffset)
+                        YOffset = max(min(YOffset + move.y, maxYOffset), -maxYOffset)
+                    }
+                }
+                .graphicsLayer(
+                    scaleX = scale,
+                    scaleY = scale,
+                    translationX = XOffset,
+                    translationY = YOffset
+                )
         ) {
             imageFiles?.forEach {
+                item {
                     Image(
                         bitmap = BitmapFactory.decodeFile(it.absolutePath).asImageBitmap(),
                         contentDescription = null,
@@ -104,4 +135,5 @@ fun DSBDayViewContent(activity: ComponentActivity){
                 }
             }
         }
+    }
 }

app/src/main/java/com/schoolapp/cleverclass/PSEActivity.kt

@@ -79,6 +79,7 @@ fun PSEContent(activity: ComponentActivity){
     }
 }
 
+private lateinit var rootObj : JSONObject
 
 private val colors = listOf(
     Color(0xFFBCA76D),
@@ -117,7 +118,7 @@ private val elementButtonColors = listOf(
 @Composable
 fun PSEMainContent(activity: ComponentActivity) {
     val inputStream = activity.assets.open("elements_data.json")
-    val rootObj = JSONObject(InputStreamReader(inputStream).readText())
+    rootObj = JSONObject(InputStreamReader(inputStream).readText())
 
     var showInfo by remember {
         mutableStateOf(false)
@@ -204,7 +205,7 @@ fun PSEMainContent(activity: ComponentActivity) {
                     modifier = Modifier
                         .verticalScroll(rememberScrollState())
                         .horizontalScroll(rememberScrollState()),
-                    text = readElementData(rootObj, dcValue),
+                    text = readElementData(dcValue),
                     color = MaterialTheme.colorScheme.onPrimaryContainer,
                     style = MaterialTheme.typography.labelMedium
                 )
@@ -293,8 +294,8 @@ fun InformationBox(text: String, color: Color){
     }
 }
 
-private fun readElementData(jsonObject: JSONObject, int: Int): String {
+private fun readElementData(int: Int): String {
-    val elementData = jsonObject.getJSONArray("elements").getJSONObject(int)
+    val elementData = rootObj.getJSONArray("elements").getJSONObject(int)
     return "Name:\n${elementData.get("Name")}\n\n" +
             "Ordnungszahl:\n${elementData.get("Ordnungszahl")}\n\n" +
             "Gruppe:\n${elementData.get("Gruppe")}\n\n" +