QRCode/app/src/main/java/me/yoqi/qrcode/CaptureActivity.java

package me.yoqi.qrcode;

import android.Manifest;
import android.app.Activity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.os.Build;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.KeyEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.Window;
import android.view.WindowManager;
import android.widget.ImageView;
import android.widget.Toast;

import com.google.zxing.BarcodeFormat;
import com.google.zxing.Result;
import com.google.zxing.ResultPoint;
import com.google.zxing.client.android.camera.CameraManager;
import com.google.zxing.client.android.decode.BeepManager;
import com.google.zxing.client.android.decode.CaptureActivityHandler;
import com.google.zxing.client.android.decode.InactivityTimer;
import com.google.zxing.client.android.decode.ViewfinderView;
import com.google.zxing.client.android.result.ResultHandler;
import com.google.zxing.client.android.result.ResultHandlerFactory;

import java.io.IOException;
import java.util.Collection;

/**
 * 识别二维码 CaptureActivity
 *
 * @author liuyuqi
 *
 */
public final class CaptureActivity extends Activity implements SurfaceHolder.Callback {

	private static final String TAG = CaptureActivity.class.getSimpleName();

	private CameraManager cameraManager;
	private CaptureActivityHandler handler;
	private Result savedResultToShow;
	private ViewfinderView viewfinderView;
	private boolean hasSurface;
	private Collection<BarcodeFormat> decodeFormats;
	private InactivityTimer inactivityTimer;
	private String characterSet;
	private BeepManager beepManager;

	ImageView opreateView;

	ViewfinderView getViewfinderView() {
		return viewfinderView;
	}

	public Handler getHandler() {
		return handler;
	}

	public CameraManager getCameraManager() {
		return cameraManager;
	}

	@Override
	public void onCreate(Bundle icicle) {
		super.onCreate(icicle);

		Window window = getWindow();
		window.addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
		setContentView(R.layout.capture);

		hasSurface = false;
		inactivityTimer = new InactivityTimer(this);
		beepManager = new BeepManager(this);
		opreateView = (ImageView) findViewById(R.id.button_openorcloseClick);

		opreateView.setOnClickListener(new OnClickListener() {

			@Override
			public void onClick(View v) {
				if (cameraManager != null) {
					Config.KEY_FRONT_LIGHT = !Config.KEY_FRONT_LIGHT;
					if (Config.KEY_FRONT_LIGHT == true) {
						opreateView
								.setImageResource(R.drawable.mzw_camera_close);
					} else {
						opreateView
								.setImageResource(R.drawable.mzw_camera_open);
					}
					cameraManager.getConfigManager().initializeTorch(
							cameraManager.getCamera().getParameters(), false);
					onPause();
					onResume();
				}
			}
		});
	}

	@Override
	protected void onResume() {
		super.onResume();

		// CameraManager must be initialized here, not in onCreate(). This is
		// necessary because we don't
		// want to open the camera driver and measure the screen size if we're
		// going to show the help on
		// first launch. That led to bugs where the scanning rectangle was the
		// wrong size and partially
		// off screen.
		cameraManager = new CameraManager(getApplication());

		viewfinderView = (ViewfinderView) findViewById(R.id.viewfinder_view);
		viewfinderView.setCameraManager(cameraManager);

		handler = null;
		SurfaceView surfaceView = (SurfaceView) findViewById(R.id.preview_view);
		SurfaceHolder surfaceHolder = surfaceView.getHolder();
		if (hasSurface) {
			// The activity was paused but not stopped, so the surface still
			// exists. Therefore
			// surfaceCreated() won't be called, so init the camera here.
			initCamera(surfaceHolder);
		} else {
			// Install the callback and wait for surfaceCreated() to init the
			// camera.
			surfaceHolder.addCallback(this);
			surfaceHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
		}

		beepManager.updatePrefs();

		inactivityTimer.onResume();
	}

	@Override
	protected void onPause() {
		if (handler != null) {
			handler.quitSynchronously();
			handler = null;
		}
		inactivityTimer.onPause();
		cameraManager.closeDriver();
		if (!hasSurface) {
			SurfaceView surfaceView = findViewById(R.id.preview_view);
			SurfaceHolder surfaceHolder = surfaceView.getHolder();
			surfaceHolder.removeCallback(this);
		}
		super.onPause();
	}

    @Override
    protected void onStop() {
        if (handler != null) {
            handler.quitSynchronously();
            handler = null;
        }
        cameraManager.closeDriver();
        if (!hasSurface) {
            SurfaceView surfaceView = findViewById(R.id.preview_view);
            SurfaceHolder surfaceHolder = surfaceView.getHolder();
            surfaceHolder.removeCallback(this);
        }
        super.onStop();
    }

    @Override
	protected void onDestroy() {
		inactivityTimer.shutdown();
		super.onDestroy();
	}

	@Override
	public boolean onKeyDown(int keyCode, KeyEvent event) {
		switch (keyCode) {
		case KeyEvent.KEYCODE_BACK:
			// restartPreviewAfterDelay(0L);
			return super.onKeyDown(keyCode, event);
		case KeyEvent.KEYCODE_FOCUS:
		case KeyEvent.KEYCODE_CAMERA:
			// Handle these events so they don't launch the Camera app
			return true;
			// Use volume up/down to turn on light
		case KeyEvent.KEYCODE_VOLUME_DOWN:
			cameraManager.setTorch(false);
			return true;
		case KeyEvent.KEYCODE_VOLUME_UP:
			cameraManager.setTorch(true);
			return true;
		}
		return super.onKeyDown(keyCode, event);
	}

	private void decodeOrStoreSavedBitmap(Bitmap bitmap, Result result) {
		// Bitmap isn't used yet -- will be used soon
		if (handler == null) {
			savedResultToShow = result;
		} else {
			if (result != null) {
				savedResultToShow = result;
			}
			if (savedResultToShow != null) {
				Message message = Message.obtain(handler,
						R.id.decode_succeeded, savedResultToShow);
				handler.sendMessage(message);
			}
			savedResultToShow = null;
		}
	}

	@Override
	public void surfaceCreated(SurfaceHolder holder) {
		if (holder == null) {
			Log.e(TAG,
					"*** WARNING *** surfaceCreated() gave us a null surface!");
		}
		if (!hasSurface) {
			hasSurface = true;
			initCamera(holder);
		}
	}

	@Override
	public void surfaceDestroyed(SurfaceHolder holder) {
		hasSurface = false;
	}

	@Override
	public void surfaceChanged(SurfaceHolder holder, int format, int width,
			int height) {

	}

	/**
	 * A valid barcode has been found, so give an indication of success and show
	 * the results.
	 *
	 * @param rawResult
	 *            The contents of the barcode.
	 * @param barcode
	 *            A greyscale bitmap of the camera data which was decoded.
	 */
	public void handleDecode(Result rawResult, Bitmap barcode) {
		inactivityTimer.onActivity();
		ResultHandler resultHandler = ResultHandlerFactory.makeResultHandler(
				this, rawResult);

		boolean fromLiveScan = barcode != null;
		if (fromLiveScan) {
			// Then not from history, so beep/vibrate and we have an image to
			// draw on
			beepManager.playBeepSoundAndVibrate();
			// drawResultPoints(barcode, rawResult);
			viewfinderView.drawResultBitmap(barcode);
		}

		String text = rawResult.getText();
		Intent intent = new Intent(this, ResultActivity.class);
		intent.putExtra("text", text);
		startActivity(intent);
        cameraManager.closeDriver();
	}

	/**
	 * Superimpose a line for 1D or dots for 2D to highlight the key features of
	 * the barcode.
	 *
	 * @param barcode
	 *            A bitmap of the captured image.
	 * @param rawResult
	 *            The decoded results which contains the points to draw.
	 */
	private void drawResultPoints(Bitmap barcode, Result rawResult) {
		ResultPoint[] points = rawResult.getResultPoints();
		if (points != null && points.length > 0) {
			Canvas canvas = new Canvas(barcode);
			Paint paint = new Paint();
			paint.setColor(getResources().getColor(R.color.result_points));
			if (points.length == 2) {
				paint.setStrokeWidth(4.0f);
				drawLine(canvas, paint, points[0], points[1]);
			} else if (points.length == 4
					&& (rawResult.getBarcodeFormat() == BarcodeFormat.UPC_A || rawResult
							.getBarcodeFormat() == BarcodeFormat.EAN_13)) {
				// Hacky special case -- draw two lines, for the barcode and
				// metadata
				drawLine(canvas, paint, points[0], points[1]);
				drawLine(canvas, paint, points[2], points[3]);
			} else {
				paint.setStrokeWidth(10.0f);
				for (ResultPoint point : points) {
					canvas.drawPoint(point.getX(), point.getY(), paint);
				}
			}
		}
	}

	private static void drawLine(Canvas canvas, Paint paint, ResultPoint a,
			ResultPoint b) {
		canvas.drawLine(a.getX(), a.getY(), b.getX(), b.getY(), paint);
	}

	private void initCamera(SurfaceHolder surfaceHolder) {
		//		权限检测
		if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
			if (checkSelfPermission(Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
				requestPermissions(new String[]{Manifest.permission.CAMERA}, 1);
			}
		}
		if (surfaceHolder == null) {
			throw new IllegalStateException("No SurfaceHolder provided");
		}
		if (cameraManager.isOpen()) {
			Log.w(TAG,
					"initCamera() while already open -- late SurfaceView callback?");
			return;
		}
		try {
			cameraManager.openDriver(surfaceHolder);
			// Creating the handler starts the preview, which can also throw a
			// RuntimeException.
			if (handler == null) {
				handler = new CaptureActivityHandler(this, viewfinderView,
						decodeFormats, characterSet, cameraManager);
			}
			decodeOrStoreSavedBitmap(null, null);
		} catch (IOException ioe) {
			Log.w(TAG, ioe);
			Toast.makeText(this, R.string.camera_problem, Toast.LENGTH_SHORT)
					.show();
			finish();
		} catch (RuntimeException e) {
			// Barcode Scanner has seen crashes in the wild of this variety:
			// java.?lang.?RuntimeException: Fail to connect to camera service
			Log.w(TAG, "Unexpected error initializing camera", e);
			Toast.makeText(this, R.string.framwork_problem, Toast.LENGTH_SHORT)
					.show();
		}
	}

	public void restartPreviewAfterDelay(long delayMS) {
		if (handler != null) {
			handler.sendEmptyMessageDelayed(R.id.restart_preview, delayMS);
		}
	}

	public void drawViewfinder() {
		viewfinderView.drawViewfinder();
	}
}