我从代码https://github.com/josnidhin/Android-Camera-Example获得了帮助
但面临一些问题,如:
- 如何添加自动对焦和闪光灯功能。-在最后编辑的代码中解决
- 当屏幕方向为 270 时,实际视图显示旋转 180 度。
- 捕获视图显示拉伸。
我调用自定义相机类的代码
Camera cam = Camera.open();
if (null == cam)
{
// no camera exists
Intent i = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(i, RESULT_LOAD_IMAGE);
}
else
{
cam.release();
Intent intent = new Intent(CreateList.this, CamTestActivity.class);
startActivityForResult(intent, TAKE_PICTURE);
}
自定义相机类CamTestActivity.class
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.hardware.Camera;
import android.hardware.Camera.AutoFocusCallback;
import android.hardware.Camera.PictureCallback;
import android.hardware.Camera.ShutterCallback;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.SurfaceView;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnLongClickListener;
import android.view.ViewGroup.LayoutParams;
import android.view.Window;
import android.view.WindowManager;
import android.widget.Button;
import android.widget.FrameLayout;
import com.example.R;
public class CamTestActivity extends Activity {
private static final String TAG = "CamTestActivity";
Preview preview;
Button buttonClick, buttonCancel;
Camera camera;
String fileName;
Activity act;
Context ctx;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ctx = this;
act = this;
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.take_picture);
preview = new Preview(this, (SurfaceView) findViewById(R.id.surfaceView));
preview.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.FILL_PARENT));
((FrameLayout) findViewById(R.id.preview)).addView(preview);
preview.setKeepScreenOn(true);
buttonClick = (Button) findViewById(R.id.buttonClick);
buttonCancel = (Button) findViewById(R.id.buttonCancel);
buttonClick.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
camera.takePicture(shutterCallback, rawCallback, jpegCallback);
}
});
buttonClick.setOnLongClickListener(new OnLongClickListener() {
@Override
public boolean onLongClick(View arg0) {
camera.autoFocus(new AutoFocusCallback() {
@Override
public void onAutoFocus(boolean focus_flag, Camera cam) {
if (focus_flag)
cam.takePicture(shutterCallback, rawCallback, jpegCallback);
}
});
return true;
}
});
buttonCancel.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
finish();
}
});
}
@Override
protected void onResume() {
super.onResume();
// preview.camera = Camera.open();
camera = Camera.open(0);
camera.startPreview();
preview.setCamera(camera);
}
@Override
protected void onPause() {
if (camera != null) {
camera.stopPreview();
preview.setCamera(null);
camera.release();
camera = null;
}
super.onPause();
}
private void resetCam() {
camera.startPreview();
preview.setCamera(camera);
Intent i = new Intent();
i.putExtra("captured_img", fileName);
setResult(RESULT_OK, i);
finish();
}
ShutterCallback shutterCallback = new ShutterCallback() {
public void onShutter() {
// Log.d(TAG, "onShutter'd");
}
};
PictureCallback rawCallback = new PictureCallback() {
public void onPictureTaken(byte[] data, Camera camera) {
// Log.d(TAG, "onPictureTaken - raw");
}
};
PictureCallback jpegCallback = new PictureCallback() {
public void onPictureTaken(byte[] data, Camera camera) {
FileOutputStream outStream = null;
try {
// Write to SD Card
fileName = String.format(Environment.getExternalStorageDirectory() + "/FansRave_UploadDeal_Pic.jpg");
outStream = new FileOutputStream(fileName);
outStream.write(data);
outStream.close();
Log.d(TAG, "onPictureTaken - wrote bytes: " + data.length);
resetCam();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
Log.d(TAG, "onPictureTaken - jpeg");
}
};
}
预览.class
import java.io.IOException;
import java.util.List;
import android.content.Context;
import android.content.pm.PackageManager;
import android.content.res.Configuration;
import android.hardware.Camera;
import android.hardware.Camera.Parameters;
import android.hardware.Camera.Size;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.ViewGroup;
class Preview extends ViewGroup implements SurfaceHolder.Callback {
private final String TAG = "Preview";
SurfaceView mSurfaceView;
SurfaceHolder mHolder;
Size mPreviewSize;
List<Size> mSupportedPreviewSizes;
Camera mCamera;
Context mContext;
Preview(Context context, SurfaceView sv) {
super(context);
mContext = context;
mSurfaceView = sv;
mHolder = mSurfaceView.getHolder();
mHolder.addCallback(this);
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
}
public void setCamera(Camera camera) {
mCamera = camera;
if (mCamera != null) {
mSupportedPreviewSizes = mCamera.getParameters().getSupportedPreviewSizes();
requestLayout();
// get Camera parameters
Camera.Parameters params = mCamera.getParameters();
List<String> focusModes = params.getSupportedFocusModes();
if (focusModes.contains(Camera.Parameters.FOCUS_MODE_AUTO)) {
// set the focus mode
params.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO);
// set Camera parameters
mCamera.setParameters(params);
}
}
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
// We purposely disregard child measurements because act as a
// wrapper to a SurfaceView that center the camera preview instead
// of stretching it.
final int width = resolveSize(getSuggestedMinimumWidth(), widthMeasureSpec);
final int height = resolveSize(getSuggestedMinimumHeight(), heightMeasureSpec);
setMeasuredDimension(width, height);
if (mSupportedPreviewSizes != null) {
mPreviewSize = getOptimalPreviewSize(mSupportedPreviewSizes, width, height);
}
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
if (changed && getChildCount() > 0) {
final View child = getChildAt(0);
final int width = r - l;
final int height = b - t;
int previewWidth = width;
int previewHeight = height;
if (mPreviewSize != null) {
previewWidth = mPreviewSize.width;
previewHeight = mPreviewSize.height;
}
// Center the child SurfaceView within the parent.
if (width * previewHeight > height * previewWidth) {
final int scaledChildWidth = previewWidth * height / previewHeight;
child.layout((width - scaledChildWidth) / 2, 0, (width + scaledChildWidth) / 2, height);
} else {
final int scaledChildHeight = previewHeight * width / previewWidth;
child.layout(0, (height - scaledChildHeight) / 2, width, (height + scaledChildHeight) / 2);
}
}
}
public void surfaceCreated(SurfaceHolder holder) {
// The Surface has been created, acquire the camera and tell it where to draw.
try {
if (mCamera != null) {
if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_LANDSCAPE) {
Global.orientation = "LANDSCAPE";
Log.e("Orientation mode", "" + Global.orientation);
} else if (getResources().getConfiguration().orientation == Configuration.ORIENTATION_PORTRAIT) {
mCamera.stopPreview();
mCamera.setDisplayOrientation(90);
mCamera.startPreview();
Global.orientation = "PORTRAIT";
Log.e("Orientation mode", "" + Global.orientation);
}
mCamera.setPreviewDisplay(holder);
}
} catch (IOException exception) {
Log.e(TAG, "IOException caused by setPreviewDisplay()", exception);
mCamera.release();
mCamera = null;
}
}
public void surfaceDestroyed(SurfaceHolder holder) {
// Surface will be destroyed when we return, so stop the preview.
if (mCamera != null) {
mCamera.stopPreview();
mCamera.setPreviewCallback(null);
mCamera.release();
mCamera = null;
}
}
private Size getOptimalPreviewSize(List<Size> sizes, int w, int h) {
final double ASPECT_TOLERANCE = 0.2;
double targetRatio = (double) w / h;
if (sizes == null) return null;
Size optimalSize = null;
double minDiff = Double.MAX_VALUE;
int targetHeight = h;
// Try to find an size match aspect ratio and size
for (Size size : sizes) {
double ratio = (double) size.width / size.height;
if (Math.abs(ratio - targetRatio) > ASPECT_TOLERANCE) continue;
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
// Cannot find the one match the aspect ratio, ignore the requirement
if (optimalSize == null) {
minDiff = Double.MAX_VALUE;
for (Size size : sizes) {
if (Math.abs(size.height - targetHeight) < minDiff) {
optimalSize = size;
minDiff = Math.abs(size.height - targetHeight);
}
}
}
return optimalSize;
}
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
if (mCamera != null) {
Camera.Parameters parameters = mCamera.getParameters();
parameters.setPreviewSize(mPreviewSize.width, mPreviewSize.height);
// for flash
if (mContext.getPackageManager().hasSystemFeature(PackageManager.FEATURE_CAMERA_FLASH))
parameters.setFlashMode(Parameters.FLASH_MODE_AUTO);
requestLayout();
mCamera.setParameters(parameters);
mCamera.startPreview();
mCamera.autoFocus(null);
}
}
}
XML 文件take_picture.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/layout"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<FrameLayout
android:id="@+id/preview"
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="1" >
<SurfaceView
android:id="@+id/surfaceView"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:orientation="vertical" >
<Button
android:id="@+id/buttonClick"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:background="@drawable/button_gradient" />
<Button
android:id="@+id/buttonCancel"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:text="Cancel" />
</RelativeLayout>
</FrameLayout>
</LinearLayout>