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

坏的质量

根据我的经验,如果我们使用

Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(intent, RESULT_ADD_PHOTO);

和处理onActivityResult()

Bitmap thumbnail= (Bitmap) data.getExtras().get("data");

它只会给你一个缩略图,当然有一个坏的质量。

不错的质量

您可以显示相机和保存您的图像文件在公共目录,例如在文档目录

在onClick()中使用这个

String imagePath = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOCUMENTS) +
                File.separator + "your_image_name.jpeg";
Intent i =new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
imageFile = new File(imagePath );
i.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(imageFile));
startActivityForResult(i, RESULT_ADD_PHOTO);

在onActivityResult()中

Bitmap imageBitmap1 = BitmapFactory.decodeFile(imageFile.getAbsolutePath());
Matrix matrix = new Matrix();
matrix.postRotate(90);
Bitmap imageBitmap = Bitmap.createBitmap(imageBitmap1, 0, 0, imageBitmap1.getWidth(), imageBitmap1.getHeight(), matrix, true);
binding.imageView.setImageBitmap(imageBitmap);

我使用postRotate(),因为在我的代码中,图像结果向左旋转,所以我需要将其旋转90

其他回答

从相机捕获照片+从图库中选择图像,并将其设置为布局或imageview的背景。下面是示例代码。

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;

    import android.provider.MediaStore;
    import android.util.Log;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.widget.AdapterView;
    import android.widget.AdapterView.OnItemClickListener;
    import android.widget.GridView;
    import android.widget.ImageView;
    import android.widget.LinearLayout;

    public class Post_activity extends Activity
    {
        final int TAKE_PICTURE = 1;
        final int ACTIVITY_SELECT_IMAGE = 2;

        ImageView openCameraOrGalleryBtn,cancelBtn;
        LinearLayout backGroundImageLinearLayout;

        public void onCreate(Bundle savedBundleInstance) {
            super.onCreate(savedBundleInstance);
            overridePendingTransition(R.anim.slide_up,0);
            setContentView(R.layout.post_activity);

            backGroundImageLinearLayout=(LinearLayout)findViewById(R.id.background_image_linear_layout);
            cancelBtn=(ImageView)findViewById(R.id.cancel_icon);

            openCameraOrGalleryBtn=(ImageView)findViewById(R.id.camera_icon);



            openCameraOrGalleryBtn.setOnClickListener(new OnClickListener() {

                @Override
                public void onClick(View v) {
                    // TODO Auto-generated method stub

                    selectImage();
                }
            });
            cancelBtn.setOnClickListener(new OnClickListener() {

                @Override
                public void onClick(View v) {
                    // TODO Auto-generated method stub
                overridePendingTransition(R.anim.slide_down,0);
                finish();
                }
            });

        }

    public void selectImage()
        {
             final CharSequence[] options = { "Take Photo", "Choose from Gallery","Cancel" };
             AlertDialog.Builder builder = new AlertDialog.Builder(Post_activity.this);
                builder.setTitle("Add Photo!");
                builder.setItems(options,new DialogInterface.OnClickListener() {

                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        // TODO Auto-generated method stub
                        if(options[which].equals("Take Photo"))
                        {
                            Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE); 
                            startActivityForResult(cameraIntent, TAKE_PICTURE);
                        }
                        else if(options[which].equals("Choose from Gallery"))
                        {
                            Intent intent=new Intent(Intent.ACTION_PICK,android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
                            startActivityForResult(intent, ACTIVITY_SELECT_IMAGE);
                        }
                        else if(options[which].equals("Cancel"))
                        {
                            dialog.dismiss();
                        }

                    }
                });
                builder.show();
        }
        public void onActivityResult(int requestcode,int resultcode,Intent intent)
        {
            super.onActivityResult(requestcode, resultcode, intent);
            if(resultcode==RESULT_OK)
            {
                if(requestcode==TAKE_PICTURE)
                {
                    Bitmap photo = (Bitmap)intent.getExtras().get("data"); 
                    Drawable drawable=new BitmapDrawable(photo);
                    backGroundImageLinearLayout.setBackgroundDrawable(drawable);

                }
                else if(requestcode==ACTIVITY_SELECT_IMAGE)
                {
                    Uri selectedImage = intent.getData();
                    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));
                    Drawable drawable=new BitmapDrawable(thumbnail);
                    backGroundImageLinearLayout.setBackgroundDrawable(drawable);


                }
            }
        }

        public void onBackPressed() {
            super.onBackPressed();
            //overridePendingTransition(R.anim.slide_down,0);
        }
    }

Add these permission in Androidmenifest.xml file

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

您可以使用自定义相机与缩略图图像。 你可以看看我的项目。

2021年5月,爪哇

在处理了本文旁边所述的必要权限后, 在manifest中添加:

<uses-permission 
    android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission 
    android:name="android.permission.WRITE_EXTERNAL_STORAGE"
    android:maxSdkVersion="18"  />
<uses-permission android:name="android.permission.CAMERA" />
<uses-feature
    android:name="android.hardware.camera"
    android:required="true" />
....

    <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/provider_paths" />
    </provider>
....

其中${applicationId}是应用程序的包名,例如my.app.com。

在res - > xml > provider_paths.xml

<?xml version="1.0" encoding="utf-8"?>
 <paths>
  <external-files-path name="my_images" path="Pictures" />
  <external-path name="external_files" path="."/>
    <files-path
    name="files"   path="." />
    <external-cache-path
      name="images" path="." />
 </paths>

在活动:

private void onClickCaptureButton(View view) {
    Intent takePictureIntent_ = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
    // Ensure that there's a camera activity to handle the intent
    if (takePictureIntent_.resolveActivity(getPackageManager()) != null) {
        // Create the File where the photo should go
        File photoFile_ = null;
        try {
            photoFile_ = createImageFile();
        } catch (IOException ex) {
        }
        if(photoFile_!=null){
            picturePath=photoFile_.getAbsolutePath();
        }
        // Continue only if the File was successfully created
        if (photoFile_ != null) {
            Uri photoURI_ = FileProvider.getUriForFile(this,
               "my.app.com.fileprovider", photoFile_);
            takePictureIntent_.putExtra(MediaStore.EXTRA_OUTPUT, photoURI_);
            startActivityForResult(takePictureIntent_, REQUEST_IMAGE_CAPTURE);
        }
    }
}

还有三招:

...
private static String picturePath;
private static final int REQUEST_IMAGE_CAPTURE = 2;
...
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_ = getExternalFilesDir(Environment.DIRECTORY_PICTURES);
    File image_ = File.createTempFile(
            imageFileName_,  /* prefix */
            ".jpg",         /* suffix */
            storageDir_      /* directory */
    );

    // Save a file: path for use with ACTION_VIEW intents
    picturePath= image_.getAbsolutePath();
    return image_;
}

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
   if(requestCode == REQUEST_IMAGE_CAPTURE && resultCode == Activity.RESULT_OK 
   ){

        try {
            File file_ = new File(picturePath);
            Uri uri_ = FileProvider.getUriForFile(this,
                    "my.app.com.fileprovider", file_);
            rasm.setImageURI(uri_);
        } catch (/*IO*/Exception e) {
            e.printStackTrace();
        }
    }
}

and

@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
    savedInstanceState.putString("safar", picturePath);
    // Always call the superclass so it can save the view hierarchy state
    super.onSaveInstanceState(savedInstanceState);
}

and:

 @Override
 protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    if (savedInstanceState != null) {
        picturePath = savedInstanceState.getString("safar");
    }
 ....
}

在活动:

@Override
    protected void onCreate(Bundle savedInstanceState) {
                 image = (ImageView) findViewById(R.id.imageButton);
        image.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                try {
                SimpleDateFormat sdfPic = new SimpleDateFormat(DATE_FORMAT);
                currentDateandTime = sdfPic.format(new Date()).replace(" ", "");
                File imagesFolder = new File(IMAGE_PATH, currentDateandTime);
                imagesFolder.mkdirs();
                Random generator = new Random();
                int n = 10000;
                n = generator.nextInt(n);
                String fname = IMAGE_NAME + n + IMAGE_FORMAT;
                File file = new File(imagesFolder, fname);
                outputFileUri = Uri.fromFile(file);
                cameraIntent= new Intent(
                        android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
                cameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, outputFileUri);
                                startActivityForResult(cameraIntent, CAMERA_DATA);
                }catch(Exception e) {
                    e.printStackTrace();
                }

            }
        });
           @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        switch(requestCode) {
        case CAMERA_DATA :
                final int IMAGE_MAX_SIZE = 300;
                try {
                    // Bitmap bitmap;
                    File file = null;
                    FileInputStream fis;
                    BitmapFactory.Options opts;
                    int resizeScale;
                    Bitmap bmp;
                    file = new File(outputFileUri.getPath());
                    // This bit determines only the width/height of the
                    // bitmap
                    // without loading the contents
                    opts = new BitmapFactory.Options();
                    opts.inJustDecodeBounds = true;
                    fis = new FileInputStream(file);
                    BitmapFactory.decodeStream(fis, null, opts);
                    fis.close();

                    // Find the correct scale value. It should be a power of
                    // 2
                    resizeScale = 1;

                    if (opts.outHeight > IMAGE_MAX_SIZE
                            || opts.outWidth > IMAGE_MAX_SIZE) {
                        resizeScale = (int) Math.pow(2, (int) Math.round(Math.log(IMAGE_MAX_SIZE/ (double) Math.max(opts.outHeight, opts.outWidth)) / Math.log(0.5)));
                    }

                    // Load pre-scaled bitmap
                    opts = new BitmapFactory.Options();
                    opts.inSampleSize = resizeScale;
                    fis = new FileInputStream(file);
                    bmp = BitmapFactory.decodeStream(fis, null, opts);
                    Bitmap getBitmapSize = BitmapFactory.decodeResource(
                            getResources(), R.drawable.male);
                    image.setLayoutParams(new RelativeLayout.LayoutParams(
                            200,200));//(width,height);
                    image.setImageBitmap(bmp);
                    image.setRotation(90);
                    fis.close();

                    ByteArrayOutputStream baos = new ByteArrayOutputStream();
                    bmp.compress(Bitmap.CompressFormat.JPEG, 70, baos);
                    imageByte = baos.toByteArray();
                    break;
                } catch (FileNotFoundException e) {

                    e.printStackTrace();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        }

在layout.xml:

enter code here
<RelativeLayout
        android:id="@+id/relativeLayout2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content">


        <ImageView
            android:id="@+id/imageButton"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"

                            android:src="@drawable/XXXXXXX"
            android:textAppearance="?android:attr/textAppearanceSmall" />

在manifest.xml:

< uses-permission android: name = " android.permission。CAMERA" /> <uses-feature android:name="android.硬件。相机" / >

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());