android 二维码扫描的逻辑
用的是ZXing库
依赖有
//二维码依赖（ZXing库） implementation 'com.journeyapps:zxing-android-embedded:4.3.0' implementation 'androidx.appcompat:appcompat:1.4.2'
1.建立一个二维码扫描的工具类（QrCodeScanner）
里面的逻辑有
- 可以根据不同的标识符处理不同的扫描出来的结果
- 权限的处理
public class QrCodeScanner { private static final int CAMERA_REQUEST_CODE = 100; // 相机权限请求码 private static final String TAG = "QrCodeScanner"; // 日志标签 private final Fragment fragment; // 用于启动扫描的Fragment private final String identifier; // 标识符，用于区分不同的扫描请求 private final ScanResultCallback callback; // 扫描结果回调接口 // 扫描结果回调接口，用于处理扫描结果 public interface ScanResultCallback { void onScanResult(String msg); } // 构造函数，初始化Fragment、标识符和回调接口 public QrCodeScanner(Fragment fragment, String identifier, ScanResultCallback callback) { this.fragment = fragment; this.identifier = identifier; this.callback = callback; } // 启动二维码扫描 public void startScan() { Log.d(TAG, "startScan: Initiating scan"); // 检查相机权限 if (ContextCompat.checkSelfPermission(fragment.requireContext(), android.Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) { Log.d(TAG, "startScan: Camera permission not granted, requesting permission"); // 如果没有权限，请求相机权限 fragment.requestPermissions(new String[]{android.Manifest.permission.CAMERA}, CAMERA_REQUEST_CODE); } else { // 已有权限，启动二维码扫描 Log.d(TAG, "startScan: Camera permission granted, starting scan"); initiateScan(); } } // 实际启动扫描的方法 private void initiateScan() { Log.d(TAG, "initiateScan: Starting QR code scan"); Intent intent = new Intent(fragment.getActivity(), CustomCaptureActivity.class); fragment.startActivityForResult(intent, CAMERA_REQUEST_CODE); } // 处理权限请求结果 public void handlePermissionsResult(int requestCode, @NonNull int[] grantResults) { if (requestCode == CAMERA_REQUEST_CODE) { if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) { Log.d(TAG, "handlePermissionsResult: Camera permission granted, starting scan"); initiateScan(); // 如果权限被授予，启动扫描 } else { Log.d(TAG, "handlePermissionsResult: Camera permission denied"); Toast.makeText(fragment.getContext(), "相机权限被拒绝，无法进行二维码扫描", Toast.LENGTH_SHORT).show(); } } } // 处理扫描结果 public void handleScanResult(int requestCode, int resultCode, Intent data) { if (requestCode == CAMERA_REQUEST_CODE && resultCode == Activity.RESULT_OK && data != null) { String scannedText = data.getStringExtra("SCANNED_TEXT"); Log.d(TAG, "handleScanResult: Scanned text = " + scannedText); handleScannedResult(scannedText); } else { Log.d(TAG, "handleScanResult: Scan failed or cancelled"); Toast.makeText(fragment.getContext(), "扫描失败或已取消", Toast.LENGTH_SHORT).show(); } } // 根据不同的标识符处理扫描结果 private void handleScannedResult(String scannedText) { if ("com/example/bighealth/mine/family".equals(identifier)) { Log.d(TAG, "handleScannedResult: Processing result for family identifier"); // 将扫描结果传递给 FamilyActivity Intent intent = new Intent(fragment.getActivity(), FamilyActivity.class); intent.putExtra("scannedContent", scannedText); fragment.getActivity().startActivity(intent); } else { Log.d(TAG, "handleScannedResult: Unhandled identifier: " + identifier); if (callback != null) { callback.onScanResult(scannedText); } } } }
2.建立一个CustomCaptureActivity（用来自定义扫描界面和解码）
这里我搞了个扫描线，和四角的框。
扫描的线我的逻辑是搞了一个正方形的框，扫描的线就在这个正方形里面移动，因为我还能获取到实际扫描框的大小，只能这样曲线救国了
public class CustomCaptureActivity extends Activity { private static final String TAG = "CustomCaptureActivity"; // 日志标签 private CaptureManager capture; private CustomDecoratedBarcodeView barcodeScannerView; private ImageView scannerLine; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.zxing_custom_capture); // 使用自定义的布局 // 初始化BarcodeScannerView和扫描线 barcodeScannerView = findViewById(R.id.zxing_barcode_scanner); // 使用自定义的DecoratedBarcodeView scannerLine = findViewById(R.id.scanner_line); // 启动扫描线动画 startScannerAnimation(); // 初始化CaptureManager Log.d(TAG, "Initializing CaptureManager..."); capture = new CaptureManager(this, barcodeScannerView); // 从Intent中初始化并启动解码 Log.d(TAG, "Initializing from intent..."); capture.initializeFromIntent(getIntent(), savedInstanceState); Log.d(TAG, "Starting QR code decode..."); capture.decode(); // 设置解码回调 barcodeScannerView.decodeContinuous(new BarcodeCallback() { @Override public void barcodeResult(BarcodeResult result) { if (result != null) { String scannedText = result.getText(); Log.d(TAG, "Scanned text: " + scannedText); // 返回扫描结果 Intent resultIntent = new Intent(); resultIntent.putExtra("SCANNED_TEXT", scannedText); setResult(Activity.RESULT_OK, resultIntent); finish(); // 关闭活动 } } @Override public void possibleResultPoints(List<ResultPoint> resultPoints) { // 可以处理可能的结果点 } }); } private void startScannerAnimation() { if (scannerLine != null) { View scannerFrame = findViewById(R.id.scanner_frame); int frameHeight = scannerFrame.getLayoutParams().height; TranslateAnimation animation = new TranslateAnimation( 0, 0, // x从0到0 0, frameHeight); // y从0到frameHeight animation.setDuration(2000); // 动画持续时间2秒 animation.setRepeatCount(Animation.INFINITE); // 无限循环 animation.setRepeatMode(Animation.REVERSE); // 动画反向播放 scannerLine.startAnimation(animation); // 启动动画 } } @Override protected void onResume() { super.onResume(); Log.d(TAG, "Resuming CaptureManager..."); capture.onResume(); } @Override protected void onPause() { super.onPause(); Log.d(TAG, "Pausing CaptureManager..."); capture.onPause(); } @Override protected void onDestroy() { super.onDestroy(); Log.d(TAG, "Destroying CaptureManager..."); capture.onDestroy(); } @Override public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) { Log.d(TAG, "Handling permissions result..."); capture.onRequestPermissionsResult(requestCode, permissions, grantResults); } @Override public boolean onKeyDown(int keyCode, KeyEvent event) { Log.d(TAG, "Handling key down event: " + keyCode); return barcodeScannerView.onKeyDown(keyCode, event) || super.onKeyDown(keyCode, event); } }
上面的代码用的是下面这个自定义布局
<?xml version="1.0" encoding="utf-8"?> <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent"> <!-- 使用自定义的 CustomDecoratedBarcodeView --> <com.example.bighealth.customView.CustomDecoratedBarcodeView android:id="@+id/zxing_barcode_scanner" android:layout_width="match_parent" android:layout_height="match_parent"/> <!-- 自定义扫描框 (正方形) --> <RelativeLayout android:id="@+id/scanner_frame" android:layout_width="310dp" android:layout_height="250dp" android:layout_gravity="center" android:background="@android:color/transparent"> <!-- 自定义扫描线 --> <ImageView android:id="@+id/scanner_line" android:layout_width="match_parent" android:layout_height="4dp" android:background="#E8B66C" android:layout_alignParentTop="true" /> </RelativeLayout> </FrameLayout>
3.工具都做好了，接下来就是怎么用
// 初始化二维码扫描器，传入标识符"family" qrCodeScanner = new QrCodeScanner(this, "com/example/bighealth/mine/family", new QrCodeScanner.ScanResultCallback() { @Override public void onScanResult(String msg) { // 将服务器返回的msg内容打印到日志中 Log.d(TAG, "服务器返回的消息: " + msg); scannedQrCodeContent = msg; fetchUserData(scannedQrCodeContent); Log.d(TAG, "fetchUserData 方法被调用"); } });