我想写一个模块,在点击一个按钮,相机打开,我可以点击和捕捉图像。如果我不喜欢图像,我可以删除它,然后点击另一个图像,然后选择图像,它应该返回并在活动中显示该图像。


当前回答

拍摄照片+从图库中选择:

        a = (ImageButton)findViewById(R.id.imageButton1);

        a.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View v) {

                selectImage();

            }

        });
    }
    private File savebitmap(Bitmap bmp) {
      String extStorageDirectory = Environment.getExternalStorageDirectory().toString();
      OutputStream outStream = null;
     // String temp = null;
        File file = new File(extStorageDirectory, "temp.png");
      if (file.exists()) {
       file.delete();
       file = new File(extStorageDirectory, "temp.png");

      }

      try {
       outStream = new FileOutputStream(file);
       bmp.compress(Bitmap.CompressFormat.PNG, 100, outStream);
       outStream.flush();
       outStream.close();

      } catch (Exception e) {
       e.printStackTrace();
       return null;
      }
      return file;
     }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }
     private void selectImage() {



            final CharSequence[] options = { "Take Photo", "Choose from Gallery","Cancel" };



            AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);

            builder.setTitle("Add Photo!");

            builder.setItems(options, new DialogInterface.OnClickListener() {

                @Override

                public void onClick(DialogInterface dialog, int item) {

                    if (options[item].equals("Take Photo"))

                    {

                        Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

                        File f = new File(android.os.Environment.getExternalStorageDirectory(), "temp.jpg");

                        intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(f));
                        //pic = f;

                        startActivityForResult(intent, 1);


                    }

                    else if (options[item].equals("Choose from Gallery"))

                    {

                        Intent intent = new   Intent(Intent.ACTION_PICK,android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);

                        startActivityForResult(intent, 2);



                    }

                    else if (options[item].equals("Cancel")) {

                        dialog.dismiss();

                    }

                }

            });

            builder.show();

        }



        @Override

        protected void onActivityResult(int requestCode, int resultCode, Intent data) {

            super.onActivityResult(requestCode, resultCode, data);

            if (resultCode == RESULT_OK) {

                if (requestCode == 1) {
                    //h=0;
                    File f = new File(Environment.getExternalStorageDirectory().toString());

                    for (File temp : f.listFiles()) {

                        if (temp.getName().equals("temp.jpg")) {

                            f = temp;
                            File photo = new File(Environment.getExternalStorageDirectory(), "temp.jpg");
                           //pic = photo;
                            break;

                        }

                    }

                    try {

                        Bitmap bitmap;

                        BitmapFactory.Options bitmapOptions = new BitmapFactory.Options();



                        bitmap = BitmapFactory.decodeFile(f.getAbsolutePath(),

                                bitmapOptions); 



                        a.setImageBitmap(bitmap);




                        String path = android.os.Environment

                                .getExternalStorageDirectory()

                                + File.separator

                                + "Phoenix" + File.separator + "default";
                        //p = path;

                        f.delete();

                        OutputStream outFile = null;

                        File file = new File(path, String.valueOf(System.currentTimeMillis()) + ".jpg");

                        try {

                            outFile = new FileOutputStream(file);

                            bitmap.compress(Bitmap.CompressFormat.JPEG, 85, outFile);
    //pic=file;
                            outFile.flush();

                            outFile.close();


                        } catch (FileNotFoundException e) {

                            e.printStackTrace();

                        } catch (IOException e) {

                            e.printStackTrace();

                        } catch (Exception e) {

                            e.printStackTrace();

                        }

                    } catch (Exception e) {

                        e.printStackTrace();

                    }

                } else if (requestCode == 2) {



                    Uri selectedImage = data.getData();
                   // h=1;
    //imgui = selectedImage;
                    String[] filePath = { MediaStore.Images.Media.DATA };

                    Cursor c = getContentResolver().query(selectedImage,filePath, null, null, null);

                    c.moveToFirst();

                    int columnIndex = c.getColumnIndex(filePath[0]);

                    String picturePath = c.getString(columnIndex);

                    c.close();

                    Bitmap thumbnail = (BitmapFactory.decodeFile(picturePath));


                    Log.w("path of image from gallery......******************.........", picturePath+"");


                    a.setImageBitmap(thumbnail);

                }

            }

其他回答

更新(2020)

谷歌已经添加了一个新的ActivityResultRegistry API,“让你处理startActivityForResult() + onActivityResult()以及requestPermissions() + onRequestPermissionsResult()流,而无需覆盖你的活动或片段中的方法,通过ActivityResultContract带来了增加的类型安全性,并为测试这些流提供了钩子”。

该API是在androidx中添加的。和androidx.fragment 1.3.0-alpha02。

所以你现在可以这样做:

val takePicture = registerForActivityResult(ActivityResultContracts.TakePicture()) { success: Boolean ->
    if (success) {
        // The image was saved into the given Uri -> do something with it
    }
}

val imageUri: Uri = ...
button.setOnClickListener {
    takePicture.launch(imageUri)
}

查看文档了解如何使用新的Activity结果API: https://developer.android.com/training/basics/intents/result#kotlin

有许多内置的activityresultcontract,允许您做不同的事情,如选择联系人,请求权限,拍照或拍摄视频。您可能对ActivityResultContracts感兴趣。拍摄上图。

注意androidx.fragment 1.3.0-alpha04弃用了Fragment上的startActivityForResult() + onActivityResult()和requestPermissions() + onRequestPermissionsResult() api。因此,从现在开始ActivityResultContracts似乎是一种新的做事方式。


原答案(2015)

我花了好几个小时才把它修好。代码几乎是从developer.android.com复制粘贴而来的,只有细微的区别。

在AndroidManifest.xml上请求此权限:

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

在你的Activity中,首先定义这个:

static final int REQUEST_IMAGE_CAPTURE = 1;
private Bitmap mImageBitmap;
private String mCurrentPhotoPath;
private ImageView mImageView;

然后在onClick中触发这个Intent:

Intent cameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
if (cameraIntent.resolveActivity(getPackageManager()) != null) {
    // Create the File where the photo should go
    File photoFile = null;
    try {
        photoFile = createImageFile();
    } catch (IOException ex) {
        // Error occurred while creating the File
        Log.i(TAG, "IOException");
    }
    // Continue only if the File was successfully created
    if (photoFile != null) {
        cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(photoFile));
        startActivityForResult(cameraIntent, REQUEST_IMAGE_CAPTURE);
    }
}

添加以下支持方法:

private File createImageFile() throws IOException {
    // Create an image file name
    String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
    String imageFileName = "JPEG_" + timeStamp + "_";
    File storageDir = Environment.getExternalStoragePublicDirectory(
            Environment.DIRECTORY_PICTURES);
    File image = File.createTempFile(
            imageFileName,  // prefix
            ".jpg",         // suffix
            storageDir      // directory
    );

    // Save a file: path for use with ACTION_VIEW intents
    mCurrentPhotoPath = "file:" + image.getAbsolutePath();
    return image;
}

然后接收结果:

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK) {
        try {
            mImageBitmap = MediaStore.Images.Media.getBitmap(this.getContentResolver(), Uri.parse(mCurrentPhotoPath));
            mImageView.setImageBitmap(mImageBitmap);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

使它工作的是MediaStore.Images.Media.getBitmap(this.getContentResolver(), Uri.parse(mCurrentPhotoPath)),这与developer.android.com的代码不同。原始代码给了我一个FileNotFoundException。

使用下面的代码捕捉图片使用您的移动相机。 如果你使用的android版本高于棒棒糖,你也应该添加权限请求。

private void cameraIntent()
    {
          Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
          startActivityForResult(intent, REQUEST_CAMERA);
    }

@override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {  
     if (requestCode == CAMERA_REQUEST && resultCode == Activity.RESULT_OK) {  
            Bitmap photo = (Bitmap) data.getExtras().get("data"); 
            imageView.setImageBitmap(photo);
     }  
} 

你得好好研究一下相机。(我认为要做到你想要的,你必须保存当前的图像到你的应用程序,在那里做选择/删除,然后召回相机再试一次,而不是直接在相机内部重试。)

正如其他人所讨论的,使用data. getextras ().get("data")只会得到低质量的缩略图。

解决方案是通过ACTION_IMAGE_CAPTURE意图传递一个位置,告诉相机在哪里存储全质量图像。

代码是Kotlin,不需要任何权限。


val f = File("${getExternalFilesDir(null)}/imgShot")
val photoURI = FileProvider.getUriForFile(this, "${packageName}.fileprovider", f)
val intent = Intent(MediaStore.ACTION_IMAGE_CAPTURE)
        .apply { putExtra(MediaStore.EXTRA_OUTPUT, photoURI) }
startActivityForResult(intent, 1234)

然后对拍摄后的结果进行处理:

override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
    if (requestCode == 1234 && resultCode == Activity.RESULT_OK) {
        val bitmap = BitmapFactory.decodeFile(
                File("${getExternalFilesDir(null)}/imgShot").toString()
        )
        // use imageView.setImageBitmap(bitmap) or whatever
    }
}

您还需要像这里描述的那样添加一个外部FileProvider。AndroidManifest.xml:

<manifest>
    <application>

        <provider
            android:name="androidx.core.content.FileProvider"
            android:authorities="${applicationId}.fileprovider"
            android:exported="false"
            android:grantUriPermissions="true">
            <meta-data
                android:name="android.support.FILE_PROVIDER_PATHS"
                android:resource="@xml/provide_paths" />
        </provider>

    </application>
</manifest>

添加一个新文件app/src/main/res/xml/provide_paths.xml:

<?xml version="1.0" encoding="utf-8"?>
<paths>
    <external-path name="external_files" path="." />
</paths>

最后,你应该用你自己的逻辑替换1234来跟踪请求代码(通常是一个包含RequestCode.CAPTURE_IMAGE等成员的枚举)

我创建了一个对话框,可以从图库或相机中选择图像。 回调函数为

Uri,如果图像来自图库 字符串作为文件路径,如果图像是从相机捕获。 从相机中选择的图像需要作为多部分文件数据上传到互联网上

首先,我们要在AndroidManifest中定义权限,因为我们需要在创建文件和从画廊读取图像时写入外部存储

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

中创建file_paths xml文件 应用程序/ src / main / res / xml / file_paths.xml

与路径

<?xml version="1.0" encoding="utf-8"?>
<paths xmlns:android="http://schemas.android.com/apk/res/android">
    <external-path name="external_files" path="."/>
</paths>

然后我们需要定义文件提供者来生成Content uri来访问存储在外部存储器中的文件

<provider
    android:name="androidx.core.content.FileProvider"
    android:authorities="${applicationId}.provider"
    android:exported="false"
    android:grantUriPermissions="true">
    <meta-data
        android:name="android.support.FILE_PROVIDER_PATHS"
        android:resource="@xml/file_paths" />
</provider>

河流布局

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <androidx.constraintlayout.widget.Guideline
        android:id="@+id/guideline2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        app:layout_constraintGuide_percent="0.50" />

    <ImageView
        android:id="@+id/gallery"
        android:layout_width="48dp"
        android:layout_height="48dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="32dp"
        android:layout_marginEnd="8dp"
        android:layout_marginBottom="32dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="@+id/guideline2"
        app:layout_constraintTop_toTopOf="parent"
        app:srcCompat="@drawable/ic_menu_gallery" />

    <ImageView
        android:id="@+id/camera"
        android:layout_width="48dp"
        android:layout_height="0dp"
        android:layout_marginStart="8dp"
        android:layout_marginTop="32dp"
        android:layout_marginEnd="8dp"
        android:layout_marginBottom="32dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toStartOf="@+id/guideline2"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:srcCompat="@drawable/ic_menu_camera" />
</androidx.constraintlayout.widget.ConstraintLayout>

ImagePicker Dailog

public class ImagePicker extends BottomSheetDialogFragment {
ImagePicker.GetImage getImage;
public ImagePicker(ImagePicker.GetImage getImage, boolean allowMultiple) {
    this.getImage = getImage;
}
File cameraImage;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View view = inflater.inflate(R.layout.bottom_sheet_imagepicker, container, false);
    view.findViewById(R.id.camera).setOnClickListener(new View.OnClickListener() {@
        Override
        public void onClick(View view) {
            if(ActivityCompat.checkSelfPermission(getActivity(), Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
                requestPermissions(new String[] {
                    Manifest.permission.READ_EXTERNAL_STORAGE, Manifest.permission.WRITE_EXTERNAL_STORAGE
                }, 2000);
            } else {
                captureFromCamera();
            }
        }
    });
    view.findViewById(R.id.gallery).setOnClickListener(new View.OnClickListener() {@
        Override
        public void onClick(View view) {
            if(ActivityCompat.checkSelfPermission(getActivity(), Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
                requestPermissions(new String[] {
                    Manifest.permission.READ_EXTERNAL_STORAGE
                }, 2000);
            } else {
                startGallery();
            }
        }
    });
    return view;
}
public interface GetImage {
    void setGalleryImage(Uri imageUri);
    void setCameraImage(String filePath);
    void setImageFile(File file);
}@
Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if(resultCode == Activity.RESULT_OK) {
        if(requestCode == 1000) {
            Uri returnUri = data.getData();
            getImage.setGalleryImage(returnUri);
            Bitmap bitmapImage = null;
        }
        if(requestCode == 1002) {
            if(cameraImage != null) {
                getImage.setImageFile(cameraImage);
            }
            getImage.setCameraImage(cameraFilePath);
        }
    }
}
private void startGallery() {
    Intent cameraIntent = new Intent(Intent.ACTION_PICK, MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
    cameraIntent.setType("image/*");
    if(cameraIntent.resolveActivity(getActivity().getPackageManager()) != null) {
        startActivityForResult(cameraIntent, 1000);
    }
}
private String cameraFilePath;
private File createImageFile() throws IOException {
    String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
    String imageFileName = "JPEG_" + timeStamp + "_";
    File storageDir = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM), "Camera");
    File image = File.createTempFile(imageFileName, /* prefix */ ".jpg", /* suffix */ storageDir /* directory */ );
    cameraFilePath = "file://" + image.getAbsolutePath();
    cameraImage = image;
    return image;
}
private void captureFromCamera() {
    try {
        Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        intent.putExtra(MediaStore.EXTRA_OUTPUT, FileProvider.getUriForFile(getContext(), BuildConfig.APPLICATION_ID + ".provider", createImageFile()));
        startActivityForResult(intent, 1002);
    } catch(IOException ex) {
        ex.printStackTrace();
    }
}

}

像这样调用Activity或fragment 在Fragment/Activity中定义ImagePicker

ImagePicker imagePicker;

然后在点击按钮时调用dailog

      imagePicker = new ImagePicker(new ImagePicker.GetImage() {
            @Override
            public void setGalleryImage(Uri imageUri) {

                Log.i("ImageURI", imageUri + "");

                String[] filePathColumn = {MediaStore.Images.Media.DATA};

                Cursor cursor = getContext().getContentResolver().query(imageUri, filePathColumn, null, null, null);
                assert cursor != null;
                cursor.moveToFirst();

                int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
                mediaPath = cursor.getString(columnIndex);
                // Set the Image in ImageView for Previewing the Media
                imagePreview.setImageBitmap(BitmapFactory.decodeFile(mediaPath));
                cursor.close();

            }

            @Override
            public void setCameraImage(String filePath) {

                mediaPath =filePath;
                Glide.with(getContext()).load(filePath).into(imagePreview);

            }

            @Override
            public void setImageFile(File file) {

                cameraImage = file;

            }
        }, true);
        imagePicker.show(getActivity().getSupportFragmentManager(), imagePicker.getTag());