android从相册选择图片和拍照选择图片

在android开发中选择图片的方式大致可以分类两种,一种是从手机相册获取,另外一种则是通过调用手机拍照获得

  • 手机相册中获取,这种方式需要读取存储卡的权限
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
  • 相机拍照获取,需要存储卡写入权限以及摄像头权限,并且调用系统相机还涉及到一个android 7.0应用间文件共享的问题,可根据之前的适配Android7.0应用间文件共享FileProvider 方式解决,此处不做多余解释
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.CAMERA"/>

一.手机相册中获取,在android6.0以上需要处理权限动态申请的问题

if (ContextCompat.checkSelfPermission(this, Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
                    //未授权,申请授权(从相册选择图片需要读取存储卡的权限)
                    ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE}, RC_CHOOSE_PHOTO);
                } else {
                    //已授权,获取照片
                    choosePhoto();
                }

/**
权限申请结果回调
*/
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
        switch (requestCode) {
            case RC_TAKE_PHOTO:   //拍照权限申请返回
                if (grantResults.length == 2 && grantResults[0] == PackageManager.PERMISSION_GRANTED && grantResults[1] == PackageManager.PERMISSION_GRANTED) {
                    takePhoto();
                }
                break;
            case RC_CHOOSE_PHOTO:   //相册选择照片权限申请返回
                choosePhoto();
                break;
        }
    }
1.跳转系统相册获取图片的代码:
public static final int RC_CHOOSE_PHOTO = 2;

private void choosePhoto() {
        Intent intentToPickPic = new Intent(Intent.ACTION_PICK, null);
        intentToPickPic.setDataAndType(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, "image/*");
        startActivityForResult(intentToPickPic, RC_CHOOSE_PHOTO);
    }
2. 系统相册获取图片结果返回,这里使用Glide来显示图片
@Override
    protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        switch (requestCode) {
            case RC_CHOOSE_PHOTO:
                Uri uri = data.getData();
                String filePath = FileUtil.getFilePathByUri(this, uri);

                if (!TextUtils.isEmpty(filePath)) {
                    RequestOptions requestOptions1 = new RequestOptions().skipMemoryCache(true).diskCacheStrategy(DiskCacheStrategy.NONE);
                    //将照片显示在 ivImage上
                   Glide.with(this).load(filePath).apply(requestOptions1).into(ivImage);
                }
                break;
        }
    }

二.拍照选择图片,也同样需要处理权限动态申请问题,与上面一样,不多加解释,下面是调用相机拍照的代码

    public static final int RC_TAKE_PHOTO = 1;

    private String mTempPhotoPath;
    private Uri imageUri;

    private void takePhoto() {
        Intent intentToTakePhoto = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        File fileDir = new File(Environment.getExternalStorageDirectory() + File.separator + "photoTest" + File.separator);
        if (!fileDir.exists()) {
            fileDir.mkdirs();
        }

        File photoFile = new File(fileDir, "photo.jpeg");
        mTempPhotoPath = photoFile.getAbsolutePath();
        imageUri = FileProvider7.getUriForFile(this, photoFile);
        intentToTakePhoto.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
        startActivityForResult(intentToTakePhoto, RC_TAKE_PHOTO);
    }

相机拍照返回结果:

@Override
    protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        switch (requestCode) {
            case RC_TAKE_PHOTO:
                RequestOptions requestOptions = new RequestOptions().skipMemoryCache(true).diskCacheStrategy(DiskCacheStrategy.NONE);
                //将图片显示在ivImage上
                Glide.with(this).load(mTempPhotoPath).apply(requestOptions).into(ivImage);
                break;
        }
    }

三.以上两步完成了从相机拍照选择图片以及从相册选择图片两种方式,但是在从相册选择照片的返回结果处理中还涉及到了从URI获取图片真实路径的方法 String filePath = FileUtil.getFilePathByUri(this, uri); 没有解释,从URI中获取图片的真实路径,不同机型的方式不同,下面是我自己使用过很多次,在多种手机的机型上面都可以正确获取真实路径的工具类

public class FileUtil {
    /**
     * 根据URI获取文件真实路径(兼容多张机型)
     * @param context
     * @param uri
     * @return
     */
    public static String getFilePathByUri(Context context, Uri uri) {
        if ("content".equalsIgnoreCase(uri.getScheme())) {

            int sdkVersion = Build.VERSION.SDK_INT;
            if (sdkVersion >= 19) { // api >= 19
                return getRealPathFromUriAboveApi19(context, uri);
            } else { // api < 19
                return getRealPathFromUriBelowAPI19(context, uri);
            }
        } else if ("file".equalsIgnoreCase(uri.getScheme())) {
            return uri.getPath();
        }
        return null;
    }

    /**
     * 适配api19及以上,根据uri获取图片的绝对路径
     *
     * @param context 上下文对象
     * @param uri     图片的Uri
     * @return 如果Uri对应的图片存在, 那么返回该图片的绝对路径, 否则返回null
     */
    @SuppressLint("NewApi")
    private static String getRealPathFromUriAboveApi19(Context context, Uri uri) {
        String filePath = null;
        if (DocumentsContract.isDocumentUri(context, uri)) {
            // 如果是document类型的 uri, 则通过document id来进行处理
            String documentId = DocumentsContract.getDocumentId(uri);
            if (isMediaDocument(uri)) { // MediaProvider
                // 使用':'分割
                String type = documentId.split(":")[0];
                String id = documentId.split(":")[1];

                String selection = MediaStore.Images.Media._ID + "=?";
                String[] selectionArgs = {id};

                //
                Uri contentUri = null;
                if ("image".equals(type)) {
                    contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
                } else if ("video".equals(type)) {
                    contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
                } else if ("audio".equals(type)) {
                    contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
                }

                filePath = getDataColumn(context, contentUri, selection, selectionArgs);
            } else if (isDownloadsDocument(uri)) { // DownloadsProvider
                Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads/public_downloads"), Long.valueOf(documentId));
                filePath = getDataColumn(context, contentUri, null, null);
            }else if (isExternalStorageDocument(uri)) {
                // ExternalStorageProvider
                final String docId = DocumentsContract.getDocumentId(uri);
                final String[] split = docId.split(":");
                final String type = split[0];
                if ("primary".equalsIgnoreCase(type)) {
                    filePath = Environment.getExternalStorageDirectory() + "/" + split[1];
                }
            }else {
                //Log.e("路径错误");
            }
        } else if ("content".equalsIgnoreCase(uri.getScheme())) {
            // 如果是 content 类型的 Uri
            filePath = getDataColumn(context, uri, null, null);
        } else if ("file".equals(uri.getScheme())) {
            // 如果是 file 类型的 Uri,直接获取图片对应的路径
            filePath = uri.getPath();
        }
        return filePath;
    }

    /**
     * 适配api19以下(不包括api19),根据uri获取图片的绝对路径
     *
     * @param context 上下文对象
     * @param uri     图片的Uri
     * @return 如果Uri对应的图片存在, 那么返回该图片的绝对路径, 否则返回null
     */
    private static String getRealPathFromUriBelowAPI19(Context context, Uri uri) {
        return getDataColumn(context, uri, null, null);
    }

    /**
     * 获取数据库表中的 _data 列,即返回Uri对应的文件路径
     *
     * @return
     */
    private static String getDataColumn(Context context, Uri uri, String selection, String[] selectionArgs) {
        String path = null;

        String[] projection = new String[]{MediaStore.Images.Media.DATA};
        Cursor cursor = null;
        try {
            cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs, null);
            if (cursor != null && cursor.moveToFirst()) {
                int columnIndex = cursor.getColumnIndexOrThrow(projection[0]);
                path = cursor.getString(columnIndex);
            }
        } catch (Exception e) {
            if (cursor != null) {
                cursor.close();
            }
        }
        return path;
    }

    /**
     * @param uri the Uri to check
     * @return Whether the Uri authority is MediaProvider
     */
    private static boolean isMediaDocument(Uri uri) {
        return "com.android.providers.media.documents".equals(uri.getAuthority());
    }

    private static boolean isExternalStorageDocument(Uri uri) {
        return "com.android.externalstorage.documents".equals(uri.getAuthority());
    }

    /**
     * @param uri the Uri to check
     * @return Whether the Uri authority is DownloadsProvider
     */
    private static boolean isDownloadsDocument(Uri uri) {
        return "com.android.providers.downloads.documents".equals(uri.getAuthority());
    }
}

猜你喜欢

转载自blog.csdn.net/weixin_44247225/article/details/85262097