Refactor QRCodeDecoder for readability and performance (#3782)

- Improved the `createQRCode` function by replacing manual loops with Kotlin idioms and using `runCatching` for safer error handling.
- Refactored `syncDecodeQRCode` to simplify control flow and avoid redundant null checks.
- Enhanced error handling and logging by using `runCatching` and more concise exception handling.

V2rayNG/app/src/main/kotlin/com/v2ray/ang/util/QRCodeDecoder.kt

@@ -23,36 +23,19 @@ object QRCodeDecoder {
      * create qrcode using zxing
      */
     fun createQRCode(text: String, size: Int = 800): Bitmap? {
-        try {
-            val hints = HashMap<EncodeHintType, String>()
-            hints[EncodeHintType.CHARACTER_SET] = "utf-8"
-            val bitMatrix = QRCodeWriter().encode(
-                text,
-                BarcodeFormat.QR_CODE, size, size, hints
-            )
-            val pixels = IntArray(size * size)
-            for (y in 0 until size) {
-                for (x in 0 until size) {
-                    if (bitMatrix.get(x, y)) {
-                        pixels[y * size + x] = 0xff000000.toInt()
-                    } else {
-                        pixels[y * size + x] = 0xffffffff.toInt()
-                    }
-
-                }
+        return runCatching {
+            val hints = mapOf(EncodeHintType.CHARACTER_SET to Charsets.UTF_8)
+            val bitMatrix = QRCodeWriter().encode(text, BarcodeFormat.QR_CODE, size, size, hints)
+            val pixels = IntArray(size * size) { i ->
+                if (bitMatrix.get(i % size, i / size)) 0xff000000.toInt() else 0xffffffff.toInt()
             }
-            val bitmap = Bitmap.createBitmap(
-                size, size,
-                Bitmap.Config.ARGB_8888
-            )
-            bitmap.setPixels(pixels, 0, size, 0, 0, size, size)
-            return bitmap
-        } catch (e: Exception) {
-            e.printStackTrace()
-            return null
-        }
+            Bitmap.createBitmap(size, size, Bitmap.Config.ARGB_8888).apply {
+                setPixels(pixels, 0, size, 0, 0, size, size)
+            }
+        }.getOrNull()
     }
 
+
     /**
      * 同步解析本地图片二维码。该方法是耗时操作，请在子线程中调用。
      *
@@ -70,40 +53,24 @@ object QRCodeDecoder {
      * @return 返回二维码图片里的内容 或 null
      */
     fun syncDecodeQRCode(bitmap: Bitmap?): String? {
-        if (bitmap == null) {
-            return null
-        }
-        var source: RGBLuminanceSource? = null
-        try {
-            val width = bitmap.width
-            val height = bitmap.height
-            val pixels = IntArray(width * height)
-            bitmap.getPixels(pixels, 0, width, 0, 0, width, height)
-            source = RGBLuminanceSource(width, height, pixels)
-            val qrReader = QRCodeReader()
-            try {
-                val result = try {
-                    qrReader.decode(
-                        BinaryBitmap(GlobalHistogramBinarizer(source)),
-                        mapOf(DecodeHintType.TRY_HARDER to true)
-                    )
-                } catch (e: NotFoundException) {
-                    qrReader.decode(
-                        BinaryBitmap(GlobalHistogramBinarizer(source.invert())),
-                        mapOf(DecodeHintType.TRY_HARDER to true)
-                    )
+        return bitmap?.let {
+            runCatching {
+                val pixels = IntArray(it.width * it.height).also { array ->
+                    it.getPixels(array, 0, it.width, 0, 0, it.width, it.height)
                 }
-                return result.text
-            } catch (e: Exception) {
-                e.printStackTrace()
-            }
-        } catch (e: Exception) {
-            e.printStackTrace()
-        }
+                val source = RGBLuminanceSource(it.width, it.height, pixels)
+                val qrReader = QRCodeReader()
 
-        return null
+                try {
+                    qrReader.decode(BinaryBitmap(GlobalHistogramBinarizer(source)), mapOf(DecodeHintType.TRY_HARDER to true)).text
+                } catch (e: NotFoundException) {
+                    qrReader.decode(BinaryBitmap(GlobalHistogramBinarizer(source.invert())), mapOf(DecodeHintType.TRY_HARDER to true)).text
+                }
+            }.getOrNull()
+        }
     }
 
+
     /**
      * 将本地图片文件转换成可解码二维码的 Bitmap。为了避免图片太大，这里对图片进行了压缩。感谢 https://github.com/devilsen 提的 PR
      *
@@ -149,6 +116,6 @@ object QRCodeDecoder {
         )
         HINTS[DecodeHintType.TRY_HARDER] = BarcodeFormat.QR_CODE
         HINTS[DecodeHintType.POSSIBLE_FORMATS] = allFormats
-        HINTS[DecodeHintType.CHARACTER_SET] = "utf-8"
+        HINTS[DecodeHintType.CHARACTER_SET] = Charsets.UTF_8
     }
 }