正在编写一个 body 测量应用程序。我已经能够创建相机并存储图像。我想在另一个 Activity 中使用捕获的图像，我在其中调用方法“bodyMeasurement” 我真的需要帮助才能实现这一目标。也欢迎进一步指正。谢谢
这是我的相机 Activity ；
CameraDevice.StateCallback stateCallback = new CameraDevice.StateCallback() {
@Override
public void onOpened(@NonNull CameraDevice camera) {
cameraDevice = camera;
createCameraPreview();
}
@Override
public void onDisconnected(@NonNull CameraDevice cameraDevice) {
cameraDevice.close();
}
@Override
public void onError(@NonNull CameraDevice cameraDevice, int i) {
cameraDevice.close();
cameraDevice=null;
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
textureView = (TextureView)findViewById(R.id.textureView);
//From Java 1.4 , you can use keyword 'assert' to check expression true or false
assert textureView != null;
textureView.setSurfaceTextureListener(textureListener);
btnCapture = (ImageButton)findViewById(R.id.btnCapture);
/* Dexter.withActivity(this)
.withPermissions(Manifest.permission.WRITE_EXTERNAL_STORAGE, Manifest.permission.READ_EXTERNAL_STORAGE, Manifest.permission.CAMERA)
.withListener(new MultiplePermissionsListener() {
@Override
public void onPermissionsChecked(MultiplePermissionsReport report) {
if (!report.areAllPermissionsGranted()) {
Toast.makeText(MainActivity.this, "You need to grant all permission to use this app features", Toast.LENGTH_SHORT).show();
}
}
@Override
public void onPermissionRationaleShouldBeShown(List<PermissionRequest> permissions, PermissionToken token) {
}
})
.check();*/
btnCapture.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
takePicture();
}
});
}
private void takePicture() {
if(cameraDevice == null)
return;
CameraManager manager = (CameraManager)getSystemService(Context.CAMERA_SERVICE);
try{
CameraCharacteristics characteristics = manager.getCameraCharacteristics(cameraDevice.getId());
Size[] jpegSizes = null;
if(characteristics != null)
jpegSizes = characteristics.get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP)
.getOutputSizes(ImageFormat.JPEG);
//Capture image with custom size
int width = 4608;
int height = 3456;
if(jpegSizes != null && jpegSizes.length > 0)
{
width = jpegSizes[0].getWidth();
height = jpegSizes[0].getHeight();
}
final ImageReader reader = ImageReader.newInstance(width,height,ImageFormat.JPEG,1);
List<Surface> outputSurface = new ArrayList<>(2);
outputSurface.add(reader.getSurface());
outputSurface.add(new Surface(textureView.getSurfaceTexture()));
final CaptureRequest.Builder captureBuilder = cameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_STILL_CAPTURE);
captureBuilder.addTarget(reader.getSurface());
captureBuilder.set(CaptureRequest.CONTROL_MODE, CameraMetadata.CONTROL_MODE_AUTO);
//Check orientation base on device
int rotation = getWindowManager().getDefaultDisplay().getRotation();
captureBuilder.set(CaptureRequest.JPEG_ORIENTATION,ORIENTATIONS.get(rotation));
file = new File(Environment.getExternalStorageDirectory()+"/"+ ".CnatraSamp"+".jpg");
ImageReader.OnImageAvailableListener readerListener = new ImageReader.OnImageAvailableListener() {
@Override
public void onImageAvailable(ImageReader imageReader) {
Image image = null;
try{
image = reader.acquireLatestImage();
ByteBuffer buffer = image.getPlanes()[0].getBuffer();
byte[] bytes = new byte[buffer.capacity()];
buffer.get(bytes);
save(bytes);
}
catch (FileNotFoundException e)
{
e.printStackTrace();
}
catch (IOException e)
{
e.printStackTrace();
}
finally {
{
if(image != null)
image.close();
}
}
}
private void save(byte[] bytes) throws IOException {
OutputStream outputStream = null;
try{
outputStream = new FileOutputStream(file);
outputStream.write(bytes);
}finally {
if(outputStream != null)
outputStream.close();
}
}
};
reader.setOnImageAvailableListener(readerListener,mBackgroundHandler);
final CameraCaptureSession.CaptureCallback captureListener = new CameraCaptureSession.CaptureCallback() {
@Override
public void onCaptureCompleted(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull TotalCaptureResult result) {
super.onCaptureCompleted(session, request, result);
Toast.makeText(MainActivity.this, "Saved "+file, Toast.LENGTH_SHORT).show();
finish();
Intent i = new Intent(MainActivity.this,BlankActivity.class);
startActivity(i);
finish();
}
};
cameraDevice.createCaptureSession(outputSurface, new CameraCaptureSession.StateCallback() {
@Override
public void onConfigured(@NonNull CameraCaptureSession cameraCaptureSession) {
try{
cameraCaptureSession.capture(captureBuilder.build(),captureListener,mBackgroundHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
@Override
public void onConfigureFailed(@NonNull CameraCaptureSession cameraCaptureSession) {
}
},mBackgroundHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
private void createCameraPreview() {
try{
SurfaceTexture texture = textureView.getSurfaceTexture();
assert texture != null;
texture.setDefaultBufferSize(imageDimension.getWidth(),imageDimension.getHeight());
Surface surface = new Surface(texture);
captureRequestBuilder = cameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
captureRequestBuilder.addTarget(surface);
cameraDevice.createCaptureSession(Arrays.asList(surface), new CameraCaptureSession.StateCallback() {
@Override
public void onConfigured(@NonNull CameraCaptureSession cameraCaptureSession) {
if(cameraDevice == null)
return;
cameraCaptureSessions = cameraCaptureSession;
updatePreview();
}
@Override
public void onConfigureFailed(@NonNull CameraCaptureSession cameraCaptureSession) {
Toast.makeText(MainActivity.this, "Changed", Toast.LENGTH_SHORT).show();
}
},null);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
private void updatePreview() {
if(cameraDevice == null)
Toast.makeText(this, "Error", Toast.LENGTH_SHORT).show();
captureRequestBuilder.set(CaptureRequest.CONTROL_MODE,CaptureRequest.CONTROL_MODE_AUTO);
try{
cameraCaptureSessions.setRepeatingRequest(captureRequestBuilder.build(),null,mBackgroundHandler);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
private void openCamera() {
CameraManager manager = (CameraManager)getSystemService(Context.CAMERA_SERVICE);
try{
cameraId = manager.getCameraIdList()[1];
CameraCharacteristics characteristics = manager.getCameraCharacteristics(cameraId);
StreamConfigurationMap map = characteristics.get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP);
assert map != null;
imageDimension = map.getOutputSizes(SurfaceTexture.class)[1];
//Check realtime permission if run higher API 23
if(ActivityCompat.checkSelfPermission(this, Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED)
{
ActivityCompat.requestPermissions(this,new String[]{
Manifest.permission.CAMERA,
Manifest.permission.WRITE_EXTERNAL_STORAGE
},REQUEST_CAMERA_PERMISSION);
return;
}
manager.openCamera(cameraId,stateCallback,null);
} catch (CameraAccessException e) {
e.printStackTrace();
}
}
TextureView.SurfaceTextureListener textureListener = new TextureView.SurfaceTextureListener() {
@Override
public void onSurfaceTextureAvailable(SurfaceTexture surfaceTexture, int i, int i1) {
openCamera();
}
@Override
public void onSurfaceTextureSizeChanged(SurfaceTexture surfaceTexture, int i, int i1) {
}
@Override
public boolean onSurfaceTextureDestroyed(SurfaceTexture surfaceTexture) {
return false;
}
@Override
public void onSurfaceTextureUpdated(SurfaceTexture surfaceTexture) {
}
};
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
if(requestCode == REQUEST_CAMERA_PERMISSION)
{
if(grantResults[0] != PackageManager.PERMISSION_GRANTED)
{
Toast.makeText(this, "You can't use camera without permission", Toast.LENGTH_SHORT).show();
finish();
}
}
}
@Override
protected void onResume() {
super.onResume();
startBackgroundThread();
if(textureView.isAvailable())
openCamera();
else
textureView.setSurfaceTextureListener(textureListener);
}
@Override
protected void onPause() {
stopBackgroundThread();
super.onPause();
}
private void stopBackgroundThread() {
mBackgroundThread.quitSafely();
try{
mBackgroundThread.join();
mBackgroundThread= null;
mBackgroundHandler = null;
} catch (InterruptedException e) {
e.printStackTrace();
}
}
private void startBackgroundThread() {
mBackgroundThread = new HandlerThread("Camera Background");
mBackgroundThread.start();
mBackgroundHandler = new Handler(mBackgroundThread.getLooper());
}
我需要图像的 Activity ；
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_blank);
height = findViewById(R.id.height);
cancel = findViewById(R.id.cancel);
btnctn = findViewById(R.id.continuebtn);
cmIn = findViewById(R.id.cmIn);
height.setInputType(InputType.TYPE_CLASS_NUMBER |
InputType.TYPE_NUMBER_FLAG_DECIMAL |
InputType.TYPE_NUMBER_FLAG_SIGNED);
btnctn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (height.getText().toString().trim().isEmpty()){
Toast.makeText(BlankActivity.this,"Please input your height..",Toast.LENGTH_LONG).show();
}else {
final ProgressDialog progressDialog = new ProgressDialog(BlankActivity.this);
progressDialog.setMessage("Getting Your Measurement");
progressDialog.setTitle("Please wait!");
progressDialog.setProgressStyle(ProgressDialog.STYLE_SPINNER);
progressDialog.show(); // Display Progress Dialog
progressDialog.setCancelable(false);
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
Intent i = new Intent(BlankActivity.this, SettingsActivity.class);
startActivity(i);
progressDialog.dismiss();
}
},5000);
}
//place measurement object
bodyMeasurement();
}
});
cancel.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
BlankActivity.this.finish();
Intent i = new Intent(BlankActivity.this, HomeActivity.class);
startActivity(i);
finish();
}
});
cmIn.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if(isChecked){
num = Double.parseDouble(String.valueOf(height.getText()));
in = 0.3937 * num;
String r = String.valueOf(in);
height.setText(r);
}else {
num = Double.parseDouble(String.valueOf(height.getText()));
cm = num / 0.3937;
String r = String.valueOf(cm);
height.setText(r);
}
}
});
}
private void bodyMeasurement() {
}
}
最佳答案
正如评论中提到的，您可以从保存的图像中获取绝对路径，并将其通过 Intent 传递给需要它的 Activity。 要实现此目的，您可能需要首先将图像文件转换为 BitMap，这将为您提供图像的实际路径(有时 .getAbsolutePath() 方法返回错误的文件路径，因此转换图像是更好的解决方案首先到位图)。
这可以实现:
String filePath = file.getPath();
Bitmap imgBitmap = BitmapFactory.decodeFile(filePath);
然后要获取您保存的图像的真实路径，您需要
1)获取创建的Bitmap的Uri:
public Uri getUri(Context context, Bitmap imgBitmap) {
ByteArrayOutputStream bOutputStream = new ByteArrayOutputStream();
String path = MediaStore.Images.Media.insertImage(context.getContentResolver(),
imgBitmap, "Title", null);
return Uri.parse(path);
}
2)从Uri中获取真实路径:
public String getRealPath(Uri uri) {
String [] proj={MediaStore.Images.Media.DATA};
Cursor cursor = getContentResolver().query(uri, proj, null, null, null);
int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
String path = cursor.getString(column_index);
cursor.close();
return path;
}
在您的第一个 Activity 中，您可以通过 Intent 将图像的路径传递给另一个 Activity ，然后获取它并显示它/等等。
Intent intent = new Intent(context,OtherActivity.class);
intent.putExtra("PATH",path);
startActivity(intent);
接收你传递的数据:
Intent intent = getIntent();
String path = intent.getStringExtra("PATH");
//convert the path to image/bitmap and display the image
您还可以将整个 Bitmap 传递给您需要的 Activity，但我强烈建议您不要这样做，因为它会使用大量内存。
关于java - 如何在另一个activity中调用捕获的图像{不需要显示}，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/59604533/