paint.setColor(resultBitmap != null ? resultColor : maskColor);canvas.drawRect(0, 0, width, frame.top, paint);canvas.drawRect(0, frame.top, frame.left, frame.bottom + 1, paint);canvas.drawRect(frame.right + 1, frame.top, width, frame.bottom + 1, paint);canvas.drawRect(0, frame.bottom + 1, width, height, paint);

paint.setColor(frameColor);
canvas.drawRect(frame.left, frame.top, frame.right + 1, frame.top + 2, paint);
canvas.drawRect(frame.left, frame.top + 2, frame.left + 2, frame.bottom - 1, paint);
canvas.drawRect(frame.right - 1, frame.top, frame.right + 1, frame.bottom - 1, paint);
canvas.drawRect(frame.left, frame.bottom - 1, frame.right + 1, frame.bottom + 1, paint);

postInvalidateDelayed(ANIMATION_DELAY, frame.left, frame.top, frame.right, frame.bottom);

public void foundPossibleResultPoint(ResultPoint point) {viewfinderView.addPossibleResultPoint(point);}

public void addPossibleResultPoint(ResultPoint point) {List<ResultPoint> points = possibleResultPoints;synchronized (point) {points.add(point);int size = points.size();if (size > MAX_RESULT_POINTS) {// trim itpoints.subList(0, size - MAX_RESULT_POINTS / 2).clear();}}}

如果想深入的查看view刷新的过程，具体实现，查看下面这个链接，这个系列文章写的很详细。

   AndroidBluetooth博客：View编程(2): invalidate()再探

android入门：zxing学习笔记（三）

<uses-permission android:name="android.permission.CAMERA"/>
<uses-feature android:name="android.hardware.camera"/>

import java.io.IOException;
import android.app.Activity;
import android.hardware.Camera;
import android.os.Bundle;
import android.view.SurfaceHolder;
import android.view.SurfaceView;public class CameraTestActivity extends Activity implements SurfaceHolder.Callback {private SurfaceHolder surfaceHolder;private Camera camera;/** Called when the activity is first created. */@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.main);SurfaceView surfaceView = (SurfaceView) findViewById(R.id.preview_view);surfaceHolder = surfaceView.getHolder();surfaceHolder.addCallback(this);surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);}@Overridepublic void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {// TODO Auto-generated method stub}@Overridepublic void surfaceCreated(SurfaceHolder arg0) {// TODO Auto-generated method stubcamera = Camera.open();Camera.Parameters parameters = camera.getParameters();parameters.setPreviewSize(480, 320); // 设置camera.setParameters(parameters);try {camera.setPreviewDisplay(surfaceHolder);} catch (IOException e) {System.out.println(e.getMessage());}camera.startPreview();}@Overridepublic void surfaceDestroyed(SurfaceHolder arg0) {// TODO Auto-generated method stubif (camera != null) {camera.stopPreview();}camera.release();camera = null;}
}

<SurfaceViewandroid:id="@+id/preview_view"android:layout_width="fill_parent"android:layout_height="fill_parent" />

android:screenOrientation="landscape"

camera.setDisplayOrientation(90);

android入门：zxing学习笔记（四）

<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" />
<uses-feature android:name="android.hardware.camera.autofocus" />

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.Timer;
import java.util.TimerTask;import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.ImageFormat;
import android.graphics.Rect;
import android.graphics.YuvImage;
import android.hardware.Camera;
import android.os.Bundle;
import android.util.Log;
import android.view.Display;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.WindowManager;
import android.widget.ImageView;public class CameraTestActivity extends Activity implements SurfaceHolder.Callback {private static String TAG = CameraTestActivity.class.getSimpleName();private SurfaceHolder surfaceHolder;private Camera camera;private ImageView imageView;private Timer mTimer;private TimerTask mTimerTask;private Camera.AutoFocusCallback mAutoFocusCallBack;private Camera.PreviewCallback previewCallback;/** Called when the activity is first created. */@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.main);SurfaceView surfaceView = (SurfaceView) findViewById(R.id.preview_view);imageView = (ImageView) findViewById(R.id.image_view);surfaceHolder = surfaceView.getHolder();surfaceHolder.addCallback(this);surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);mAutoFocusCallBack = new Camera.AutoFocusCallback() {@Overridepublic void onAutoFocus(boolean success, Camera camera) {if (success) {// isAutoFocus = true;camera.setOneShotPreviewCallback(previewCallback);Log.d(TAG, "onAutoFocus success");}}};previewCallback = new Camera.PreviewCallback() {@Overridepublic void onPreviewFrame(byte[] data, Camera arg1) {if (data != null){Camera.Parameters parameters = camera.getParameters();int imageFormat = parameters.getPreviewFormat();Log.i("map", "Image Format: " + imageFormat);Log.i("CameraPreviewCallback", "data length:" + data.length);if (imageFormat == ImageFormat.NV21){// get full pictureBitmap image = null;int w = parameters.getPreviewSize().width;int h = parameters.getPreviewSize().height;Rect rect = new Rect(0, 0, w, h); YuvImage img = new YuvImage(data, ImageFormat.NV21, w, h, null);ByteArrayOutputStream baos = new ByteArrayOutputStream();if (img.compressToJpeg(rect, 100, baos)) { image =  BitmapFactory.decodeByteArray(baos.toByteArray(), 0, baos.size());imageView.setImageBitmap(image);}}}}};mTimer = new Timer();mTimerTask = new CameraTimerTask();mTimer.schedule(mTimerTask, 0, 500);}@Overridepublic void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2, int arg3) {// TODO Auto-generated method stub}@Overridepublic void surfaceCreated(SurfaceHolder arg0) {// TODO Auto-generated method stubinitCamera();}@Overridepublic void surfaceDestroyed(SurfaceHolder arg0) {// TODO Auto-generated method stubif (camera != null) {camera.stopPreview();camera.release();camera = null;}previewCallback = null;mAutoFocusCallBack = null;}public void initCamera() {camera = Camera.open();Camera.Parameters parameters = camera.getParameters();WindowManager wm = (WindowManager) getSystemService(Context.WINDOW_SERVICE); // 获取当前屏幕管理器对象Display display = wm.getDefaultDisplay(); // 获取屏幕信息的描述类parameters.setPreviewSize(display.getWidth(), display.getHeight());camera.setParameters(parameters);try {camera.setPreviewDisplay(surfaceHolder);} catch (IOException e) {System.out.println(e.getMessage());}camera.startPreview();}class CameraTimerTask extends TimerTask {@Overridepublic void run() {if (camera != null) {camera.autoFocus(mAutoFocusCallBack);}}}
}

Bitmap bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);

CameraManager.get().requestPreviewFrame(decodeThread.getHandler(), R.id.decode);//实现拍照
CameraManager.get().requestAutoFocus(this, R.id.auto_focus);//实现聚焦

public void onAutoFocus(boolean success, Camera camera) {if (autoFocusHandler != null) {Message message = autoFocusHandler.obtainMessage(autoFocusMessage, success);// Simulate continuous autofocus by sending a focus request every
// AUTOFOCUS_INTERVAL_MS milliseconds.
//Log.d(TAG, "Got auto-focus callback; requesting another");autoFocusHandler.sendMessageDelayed(message, AUTOFOCUS_INTERVAL_MS);autoFocusHandler = null;} else {Log.d(TAG, "Got auto-focus callback, but no handler for it");}}

private final Button.OnClickListener addCardListener = new TextView.OnClickListener() {@Overridepublic void onClick(View v) {//在此实现button点击后的操作}};

android入门：zxing学习笔记（五）

System.out.println(TAG + "The worker thread id = " +   Thread.currentThread().getId()); //判断线程ID

01-12 02:41:12.594: I/System.out(655): CaptureActivity The main thread id = 1
01-12 02:41:14.605: I/System.out(655): CaptureActivityHandler The handler thread id = 1
01-12 02:41:12.946: I/System.out(655): DecodeThread The worker thread id = 13
01-12 02:41:13.094: I/System.out(655): DecodeHandler The handler thread id = 13

// For now, merely tries to distinguish ISO-8859-1, UTF-8 and Shift_JIS,
// which should be by far the most common encodings. ISO-8859-1
// should not have bytes in the 0x80 - 0x9F range, while Shift_JIS
// uses this as a first byte of a two-byte character. If we see this
// followed by a valid second byte in Shift_JIS, assume it is Shift_JIS.
// If we see something else in that second byte, we'll make the risky guess
// that it's UTF-8.

for (int i = 0; i < length; i++) {int value = bytes[i] & 0xFF;if (value > 0x7F)// 如果大于127，则可能是GB2312，就开始判断该字节，和下一个字节{if (value > 0xB0 && value <= 0xF7)// 第一个字节再此范围内，则开始判断第二个自己{int value2 = bytes[i + 1] & 0xFF;if (value2 > 0xA0 && value2 <= 0xF7) {return true;}}}
}

byte[] rotatedData = new byte[data.length];for (int y = 0; y < height; y++) {for (int x = 0; x < width; x++)rotatedData[x * height + height - y - 1] = data[x + y * width];}