/*
* Copyright (C) The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.ekreutz.barcodescanner.camera;
import android.Manifest;
import android.content.Context;
import android.content.res.Configuration;
import android.support.annotation.RequiresPermission;
import android.util.AttributeSet;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.ViewGroup;
import com.google.android.gms.common.images.Size;
import com.google.android.gms.vision.Detector;
import java.io.IOException;
public class CameraSourcePreview extends ViewGroup {
private static final String TAG = "CameraSourcePreview";
public static final int FILL_MODE_COVER = 0;
public static final int FILL_MODE_FIT = 1;
private Context mContext;
private SurfaceView mSurfaceView;
private boolean mStartRequested;
private boolean mSurfaceAvailable;
private CameraSource mCameraSource;
private int mWidth = 0, mHeight = 0;
private int fillMode = FILL_MODE_COVER;
public CameraSourcePreview(Context context, AttributeSet attrs) {
super(context, attrs);
mContext = context;
mStartRequested = false;
mSurfaceAvailable = false;
mSurfaceView = new SurfaceView(context);
mSurfaceView.getHolder().addCallback(new SurfaceCallback());
addView(mSurfaceView);
}
@RequiresPermission(Manifest.permission.CAMERA)
public void start(CameraSource cameraSource) throws IOException, SecurityException {
if (cameraSource == null) {
stop();
}
mCameraSource = cameraSource;
if (mCameraSource != null) {
mStartRequested = true;
startIfReady();
}
}
public void stop() {
if (mCameraSource != null) {
mCameraSource.stop();
}
}
public void release() {
if (mCameraSource != null) {
mCameraSource.release();
mCameraSource = null;
}
}
@RequiresPermission(Manifest.permission.CAMERA)
private void startIfReady() throws IOException, SecurityException {
if (mStartRequested && mSurfaceAvailable && mCameraSource != null) {
mCameraSource.start(mSurfaceView.getHolder());
mStartRequested = false;
}
}
// Can be quite heavy, since it stops and restarts the camera
@RequiresPermission(Manifest.permission.CAMERA)
public void replaceBarcodeDetector(Detector<?> detector, boolean shouldResume) throws IOException, SecurityException {
if (mCameraSource != null) {
mCameraSource.release();
mCameraSource.setDetector(detector);
if (shouldResume && mSurfaceAvailable) {
start(mCameraSource);
}
}
}
// Set the camera stream fill mode
public void setFillMode(int fillMode) {
if (fillMode != FILL_MODE_COVER && fillMode != FILL_MODE_FIT) return;
this.fillMode = fillMode;
previewLayout();
}
private class SurfaceCallback implements SurfaceHolder.Callback {
@Override
public void surfaceCreated(SurfaceHolder surface) {
mSurfaceAvailable = true;
try {
startIfReady();
} catch (SecurityException se) {
Log.e(TAG,"Do not have permission to start the camera", se);
} catch (IOException e) {
Log.e(TAG, "Could not start camera source.", e);
}
}
@Override
public void surfaceDestroyed(SurfaceHolder surface) {
mSurfaceAvailable = false;
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
previewLayout();
}
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
mWidth = r - l;
mHeight = b - t;
previewLayout();
}
/* layout the surface that we draw the camera stream on */
private void previewLayout() {
if (mWidth == 0 || mHeight == 0) return;
// Step 1: determine the size of the camera stream
// --------------------------------
int previewWidth = 800;
int previewHeight = 480;
if (mCameraSource != null) {
mCameraSource.setRotation();
Size size = mCameraSource.getPreviewSize();
if (size != null) {
previewWidth = size.getWidth();
previewHeight = size.getHeight();
}
}
// Swap width and height sizes when in portrait, since it will be rotated 90 degrees
if (isPortraitMode()) {
int tmp = previewWidth;
previewWidth = previewHeight;
previewHeight = tmp;
}
// Step 2. Determine how to scale the stream so that it fits snugly in this view
// --------------------------------
double scaleRatio = Math.min(mWidth / (double) previewWidth, mHeight / (double) previewHeight);
int childLeft = (int) Math.round((mWidth - scaleRatio * previewWidth) / 2) + 1;
int childRight = (int) Math.round((mWidth + scaleRatio * previewWidth) / 2) - 1;
int childTop = (int) Math.round((mHeight - scaleRatio * previewHeight) / 2) + 1;
int childBottom = (int) Math.round((mHeight + scaleRatio * previewHeight) / 2) - 1;
// apply the layout to the surface
for (int i = 0; i < getChildCount(); ++i) {
getChildAt(i).layout(childLeft, childTop, childRight, childBottom);
}
// Step 3: Either fill this view, or barely touch the edges
// --------------------------------
float r = 1.0f;
if (fillMode == FILL_MODE_COVER) {
r = Math.max((float) mWidth / (childRight - childLeft), (float) mHeight / (childBottom - childTop));
} else if (fillMode == FILL_MODE_FIT) {
r = Math.min((float) mWidth / (childRight - childLeft), (float) mHeight / (childBottom - childTop));
}
setScaleX(r);
setScaleY(r);
// Step 4: try starting the stream again (if needed) after our modifications
// --------------------------------
try {
startIfReady();
} catch (SecurityException se) {
Log.e(TAG,"Do not have permission to start the camera", se);
} catch (IOException e) {
Log.e(TAG, "Could not start camera source.", e);
}
}
private boolean isPortraitMode() {
int orientation = mContext.getResources().getConfiguration().orientation;
return orientation == Configuration.ORIENTATION_PORTRAIT;
}
}
