Switching Instant layers on Android

android/src/main/java/com/pspdfkit/flutter/pspdfkit/FlutterInstantPdfActivity.kt

@@ -9,23 +9,58 @@ package com.pspdfkit.flutter.pspdfkit
 ///
 
 import android.os.Bundle
+import android.view.View
+import android.widget.AdapterView
+import android.widget.ArrayAdapter
+import android.widget.FrameLayout
+import android.widget.Spinner
 import com.pspdfkit.document.PdfDocument
 import com.pspdfkit.instant.document.InstantPdfDocument
 import com.pspdfkit.instant.exceptions.InstantException
 import com.pspdfkit.instant.ui.InstantPdfActivity
 import io.flutter.plugin.common.MethodChannel
 import java.util.concurrent.atomic.AtomicReference
 
+
 /**
  * For communication with the PSPDFKit plugin, we keep a static reference to the current
  * activity.
  */
 class FlutterInstantPdfActivity : InstantPdfActivity() {
+
+
     override fun onCreate(bundle: Bundle?) {
         super.onCreate(bundle)
         bindActivity()
+        var tokens = intent.getStringArrayExtra("tokens")?.toList()
+        var layers = intent.getStringArrayExtra("layers")?.toList()
+        var serverUrl = intent.getStringExtra("serverUrl")
+
+        //Add a dropdown for switching between layers
+        val layerSelector = Spinner(this)
+        val params = FrameLayout.LayoutParams(
+            FrameLayout.LayoutParams.WRAP_CONTENT,
+            FrameLayout.LayoutParams.WRAP_CONTENT
+        )
+        params.setMargins(0, 0, 0, 0)
+        layerSelector.layoutParams = params
+        val spinnerArrayAdapter: ArrayAdapter<String> =
+            ArrayAdapter<String>(this, android.R.layout.simple_spinner_dropdown_item, layers!!)
+        layerSelector.adapter = spinnerArrayAdapter
+        layerSelector.setSelection(0)
+        layerSelector.onItemSelectedListener = object : AdapterView.OnItemSelectedListener {
+            override fun onItemSelected(p0: AdapterView<*>?, p1: View?, p2: Int, p3: Long) {
+                setDocument(serverUrl!!, tokens!![p2])
+            }
+
+            override fun onNothingSelected(p0: AdapterView<*>?) {
+            }
+        }
+        val layout = findViewById<FrameLayout>(R.id.pspdf__activity_content)
+        layout.addView(layerSelector)
     }
 
+
     override fun onPause() {
         // Notify the Flutter PSPDFKit plugin that the activity is going to enter the onPause state.
         EventDispatcher.getInstance().notifyActivityOnPause()
@@ -36,7 +71,7 @@ class FlutterInstantPdfActivity : InstantPdfActivity() {
         super.onDestroy()
         releaseActivity()
     }
-    
+
     override fun onDocumentLoaded(pdfDocument: PdfDocument) {
         super.onDocumentLoaded(pdfDocument)
         val result = loadedDocumentResult.getAndSet(null)
@@ -48,7 +83,7 @@ class FlutterInstantPdfActivity : InstantPdfActivity() {
         val result = loadedDocumentResult.getAndSet(null)
         result?.success(false)
     }
-    
+
     override fun onSyncStarted(instantDocument: InstantPdfDocument) {
         super.onSyncStarted(instantDocument)
         EventDispatcher.getInstance()

android/src/main/java/com/pspdfkit/flutter/pspdfkit/PspdfkitPlugin.java

@@ -241,6 +241,9 @@ public void onMethodCall(@NonNull MethodCall call, @NonNull Result result) {
                 String documentUrl = call.argument("serverUrl");
                 String jwt = call.argument("jwt");
 
+                List<String> tokens= call.argument("tokens");
+                List<String> layers= call.argument("layers");
+
                 requireNotNullNotEmpty(documentUrl, "Document path");
                 requireNotNullNotEmpty(jwt, "JWT");
 
@@ -265,6 +268,10 @@ public void onMethodCall(@NonNull MethodCall call, @NonNull Result result) {
                                 .configuration(configurationAdapterInstant.build())
                                 .build();
 
+                intentInstant.putExtra("tokens", tokens.toArray(new String[tokens.size()]));
+                intentInstant.putExtra("layers", layers.toArray(new String[layers.size()]));
+                intentInstant.putExtra("serverUrl", documentUrl);
+
                 activity.startActivity(intentInstant);
 
                 break;

example/android/app/build.gradle

@@ -51,6 +51,7 @@ dependencies {
     androidTestImplementation 'androidx.test:runner:1.5.2'
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.5.1'
     implementation 'androidx.lifecycle:lifecycle-viewmodel-ktx:2.6.1'
+    implementation 'com.squareup.okhttp3:okhttp:4.2.1'
 
     constraints {
         implementation("org.jetbrains.kotlin:kotlin-stdlib-jdk7:1.8.0") {

example/lib/pspdfkit_instant_collaboration_example.dart

@@ -156,6 +156,16 @@ class _PspdfkitInstantCollaborationExampleState
                       child: const Text('Enter Document URL'),
                     ),
                   ),
+
+                  const Padding(
+                    padding: EdgeInsets.all(16.0),
+                  ),
+                  ElevatedButton(
+                      onPressed: () {
+                        _loadDocumentJson(
+                            context, 'http://192.168.0.111:3000/api/documents');
+                      },
+                      child: const Text('Load Instant Layers')),
                   // Delay for syncing local changes
                   const Padding(
                     padding: EdgeInsets.all(4.0),
@@ -250,6 +260,45 @@ class _PspdfkitInstantCollaborationExampleState
     }
   }
 
+  void _loadDocumentJson(BuildContext context, String? url) {
+    if (url != null) {
+      showDialog<dynamic>(
+          context: context,
+          barrierDismissible: false,
+          builder: (BuildContext context) {
+            return const Center(
+              child: CircularProgressIndicator(),
+            );
+          });
+
+      _getDocumentJson(url).then((data) async {
+        var doc = data['documents'][0] as Map<String, dynamic>;
+        var tokes = doc['tokens'] as List<dynamic>;
+        var layers = doc['layers'] as List<dynamic>;
+        await Pspdfkit.presentInstant(
+          'http://192.168.0.111:8080',
+          tokes[0],
+          {
+            enableInstantComments: enableComments,
+          },
+          tokes.map((e) => e as String).toList(),
+          layers.map((e) => e as String).toList(),
+        );
+        await Pspdfkit.setDelayForSyncingLocalChanges(delayTime);
+        await Pspdfkit.setListenToServerChanges(enableListenToServerChanges);
+      }).catchError((dynamic onError) {
+        ScaffoldMessenger.of(context).showSnackBar(SnackBar(
+          content: Text(onError.toString()),
+        ));
+        Navigator.of(context).pop();
+      });
+    } else {
+      if (kDebugMode) {
+        print('No URL');
+      }
+    }
+  }
+
   /// Fetches the document from the instant demo server.
   /// The server returns a JWT token that is used to authenticate the user.
   Future<InstantDocumentDescriptor> _getDocument(String url) async {
@@ -260,6 +309,21 @@ class _PspdfkitInstantCollaborationExampleState
     final document = InstantDocumentDescriptor.fromJson(data);
     return document;
   }
+
+  Future<Map<String, dynamic>> _getDocumentJson(String url) async {
+    // The header is necessary to receive valid json response.
+    try {
+      http.Response response = await client.get(Uri.parse(url), headers: {
+        'Authorization': 'Basic ${base64.encode(utf8.encode('cato:secret'))}'
+      });
+
+      final data = json.decode(response.body) as Map<String, dynamic>;
+      return data;
+    } catch (e) {
+      print(e);
+      rethrow;
+    }
+  }
 }
 
 class InstantBarcodeScanner extends StatefulWidget {

lib/pspdfkit.dart

@@ -92,11 +92,15 @@ class Pspdfkit {
   /// Returns false if the document could not be opened.
   ///
   static Future<bool?> presentInstant(String serverUrl, String jwt,
-          [dynamic configuration]) async =>
+          [dynamic configuration,
+          List<String>? tokens,
+          List<String>? layers]) async =>
       await _channel.invokeMethod('presentInstant', <String, dynamic>{
         'serverUrl': serverUrl,
         'jwt': jwt,
-        'configuration': configuration
+        'configuration': configuration,
+        'tokens': tokens,
+        'layers': layers,
       });
 
   /// Sets the value of a form field by specifying its fully qualified field name.