From 0a05674f2ff497d49c9fe13383221fe3047bb903 Mon Sep 17 00:00:00 2001
From: f321x <f@f321x.com>
Date: Tue, 24 Jun 2025 17:38:03 +0200
Subject: [PATCH] android: replace qr code scanning library

Replaces the unmaintained and unreliable
`me.dm7.barcodescanner:zxing:1.9.8` qr code scanning library used only
on android with the `com.github.markusfisch:BarcodeScannerView:1.6.0`
(https://github.com/markusfisch/BarcodeScannerView) library which seems
more actively maintained.
The `BarcodeScannerView` library is incredibly fast and scanning qr
codes is now fun again :)

wip: still looking into ways to pin the library.
---
 contrib/android/buildozer_qml.spec            |  6 +++-
 .../electrum/qr/SimpleScannerActivity.java    | 30 +++++++++----------
 2 files changed, 19 insertions(+), 17 deletions(-)

diff --git a/contrib/android/buildozer_qml.spec b/contrib/android/buildozer_qml.spec
index 7e0d32330..59da3d80e 100644
--- a/contrib/android/buildozer_qml.spec
+++ b/contrib/android/buildozer_qml.spec
@@ -160,9 +160,13 @@ android.add_jars = .buildozer/android/platform/*/build/libs_collections/Electrum
 # directory containing the files)
 android.add_src = electrum/gui/qml/java_classes/
 
+# (list) Gradle repositories to add {can be necessary for some android.gradle_dependencies}
+# e.g. android.gradle_repositories = maven { url "https://repo.spring.io/release" }
+android.add_gradle_repositories = maven { url "https://jitpack.io" }
+
 android.gradle_dependencies =
     com.android.support:support-compat:28.0.0,
-    me.dm7.barcodescanner:zxing:1.9.8
+    com.github.markusfisch:BarcodeScannerView:1.6.0
 
 android.add_activities = org.electrum.qr.SimpleScannerActivity
 
diff --git a/electrum/gui/qml/java_classes/org/electrum/qr/SimpleScannerActivity.java b/electrum/gui/qml/java_classes/org/electrum/qr/SimpleScannerActivity.java
index 0f356719f..71e2785c0 100644
--- a/electrum/gui/qml/java_classes/org/electrum/qr/SimpleScannerActivity.java
+++ b/electrum/gui/qml/java_classes/org/electrum/qr/SimpleScannerActivity.java
@@ -20,17 +20,15 @@ import androidx.core.app.ActivityCompat;
 
 import java.util.Arrays;
 
-import me.dm7.barcodescanner.zxing.ZXingScannerView;
+import de.markusfisch.android.barcodescannerview.widget.BarcodeScannerView;
 
-import com.google.zxing.Result;
-import com.google.zxing.BarcodeFormat;
 
 import org.electrum.electrum.res.R; // package set in build.gradle
 
-public class SimpleScannerActivity extends Activity implements ZXingScannerView.ResultHandler {
+public class SimpleScannerActivity extends Activity {
     private static final int MY_PERMISSIONS_CAMERA = 1002;
 
-    private ZXingScannerView mScannerView = null;
+    private BarcodeScannerView mScannerView = null;
     final String TAG = "org.electrum.SimpleScannerActivity";
 
     private boolean mAlreadyRequestedPermissions = false;
@@ -85,23 +83,23 @@ public class SimpleScannerActivity extends Activity implements ZXingScannerView.
     public void onPause() {
         super.onPause();
         if (null != mScannerView) {
-            mScannerView.stopCamera();           // Stop camera on pause
+            mScannerView.close();  // Stop camera on pause
         }
     }
 
     private void startCamera() {
-        mScannerView = new ZXingScannerView(this);
-        mScannerView.setFormats(Arrays.asList(BarcodeFormat.QR_CODE));
+        mScannerView = new BarcodeScannerView(this);
+        mScannerView.setCropRatio(0.75f); // Set crop ratio to 75% (this defines the square area shown in the scanner view)
+        // by default only Format.QR_CODE is set
         ViewGroup contentFrame = (ViewGroup) findViewById(R.id.content_frame);
         contentFrame.addView(mScannerView);
-        mScannerView.setResultHandler(this);         // Register ourselves as a handler for scan results.
-        mScannerView.startCamera();                  // Start camera on resume
-    }
-
-    @Override
-    public void handleResult(Result rawResult) {
-        //resultIntent.putExtra("format", rawResult.getBarcodeFormat().toString());
-        this.setResultAndClose(rawResult.getText());
+        mScannerView.setOnBarcodeListener(result -> {
+            // Handle the scan result
+            this.setResultAndClose(result.getText());
+            // Return false to stop scanning after first result
+            return false;
+        });
+        mScannerView.openAsync();  // Start camera on resume
     }
 
     private void setResultAndClose(String resultText) {