Question

我尝试做的是使用相机意图拍摄照片，记下URI（稍后我将使用此功能通过Firebase存储上传图像），旋转图像如果需要，然后在ImageView中显示图像。这就是我现在这样做的方式，它可以在AVD和Sony Xperia Z2运行Marshmallow 6.0.1上正常运行。但是，在Samsung Galaxy S4正在运行的Lollipop 5.0.1上进行测试时，我遇到了问题。代码无法在指定的文件路径中找到图像。我还尝试使用photoURI设置ImageView，我也尝试在创建相机意图时注释掉额外的内容，并通过data.getData()获取数据 - 这些方法都不起作用。我只是需要一种方法来从这个设备获取此图像，而不会崩溃，理想情况下不会影响设备兼容性。

编辑：导致相机意图接管，两个photoFilepath 和photoURI有价值。我一到onActivityResult，两者都返回null。

@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
    BitmapFactory.Options opt = new BitmapFactory.Options();
    opt.inSampleSize = 8;
    if (resultCode == RESULT_OK) {
        if (requestCode == CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE){
            try {
                Bitmap bit = BitmapFactory.decodeFile(photoFilepath, opt);
                Bitmap rotated = rotateImg(bit, photoFilepath);
                userPhoto.setImageBitmap(rotated);
                contentsOfImageView = rotated;
            } catch (Exception e) {
                e.printStackTrace();
                Toast.makeText(this, "Error retrieving photo, please try again", Toast.LENGTH_LONG).show();
                contentsOfImageView = null;
            }
        } // else if here for handling getting images from gallery
        addBtn.setVisibility(View.INVISIBLE);
        clearBtn.setVisibility(View.VISIBLE);
    } else { // Result was a failure
        //Toast.makeText(this, "Picture wasn't taken!", Toast.LENGTH_SHORT).show();
    }

}

private void dispatchTakePictureIntent() {
    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) {
            // Error occurred while creating the File
            Log.d(TAG, ex.toString());
        }
        // Continue only if the File was successfully created
        if (photoFile != null) {
            photoURI = FileProvider.getUriForFile(this,
                    "com.example.intheactualcodethisismypackagename",
                    photoFile);
            takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, photoURI);
            startActivityForResult(takePictureIntent, CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE);
        }
    }
}

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
    photoFilepath = image.getAbsolutePath();
    return image;
}

private Bitmap rotateImg(Bitmap before, String path) {
    ExifInterface exif = null;
    try {
        exif = new ExifInterface(path);
    } catch (IOException e) {
        e.printStackTrace();
    }
    int orientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, ExifInterface.ORIENTATION_UNDEFINED);
    Matrix matrix = new Matrix();
    switch (orientation) {
        case ExifInterface.ORIENTATION_ROTATE_90:
            matrix.setRotate(90);
            break;
        case ExifInterface.ORIENTATION_ROTATE_180:
            matrix.setRotate(180);
            break;
        case ExifInterface.ORIENTATION_ROTATE_270:
            matrix.setRotate(270);
            break;
        default:
            break;

    }
    return Bitmap.createBitmap(before, 0, 0, before.getWidth(), before.getHeight(), matrix, true);
}

Answer 1

一旦到达onActivityResult，两者都返回null。

最有可能的是，当您的应用处于后台且相机应用处于前台时，您的流程已终止。这是完全正常的，但是在任何给定的ACTION_IMAGE_CAPTURE请求中是否会发生这种情况会有所不同。

确保您在保存的实例状态Uri中保留相关内容，例如File和/或Bundle，例如this sample app：

/***
 Copyright (c) 2008-2016 CommonsWare, LLC
 Licensed under the Apache License, Version 2.0 (the "License"); you may not
 use this file except in compliance with the License. You may obtain a copy
 of the License at http://www.apache.org/licenses/LICENSE-2.0. Unless required
 by applicable law or agreed to in writing, software distributed under the
 License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS
 OF ANY KIND, either express or implied. See the License for the specific
 language governing permissions and limitations under the License.

 From _The Busy Coder's Guide to Android Development_
 https://commonsware.com/Android
 */

package com.commonsware.android.camcon;

import android.app.Activity;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.provider.MediaStore;
import android.support.v4.content.FileProvider;
import java.io.File;
import java.util.List;

public class CameraContentDemoActivity extends Activity {
  private static final String EXTRA_FILENAME=
    "com.commonsware.android.camcon.EXTRA_FILENAME";
  private static final String FILENAME="CameraContentDemo.jpeg";
  private static final int CONTENT_REQUEST=1337;
  private static final String AUTHORITY=
    BuildConfig.APPLICATION_ID+".provider";
  private static final String PHOTOS="photos";
  private File output=null;
  private Uri outputUri=null;

  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    Intent i=new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

    if (savedInstanceState==null) {
      output=new File(new File(getFilesDir(), PHOTOS), FILENAME);

      if (output.exists()) {
        output.delete();
      }
      else {
        output.getParentFile().mkdirs();
      }
    }
    else {
      output=(File)savedInstanceState.getSerializable(EXTRA_FILENAME);
    }

    outputUri=FileProvider.getUriForFile(this, AUTHORITY, output);

    if (savedInstanceState==null) {
      i.putExtra(MediaStore.EXTRA_OUTPUT, outputUri);

      if (Build.VERSION.SDK_INT>=Build.VERSION_CODES.LOLLIPOP) {
        i.addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
      }
      else {
        List<ResolveInfo> resInfoList=
          getPackageManager()
            .queryIntentActivities(i, PackageManager.MATCH_DEFAULT_ONLY);

        for (ResolveInfo resolveInfo : resInfoList) {
          String packageName = resolveInfo.activityInfo.packageName;
          grantUriPermission(packageName, outputUri,
            Intent.FLAG_GRANT_WRITE_URI_PERMISSION |
              Intent.FLAG_GRANT_READ_URI_PERMISSION);
        }
      }

      startActivityForResult(i, CONTENT_REQUEST);
    }
  }

  @Override
  protected void onSaveInstanceState(Bundle outState) {
    super.onSaveInstanceState(outState);

    outState.putSerializable(EXTRA_FILENAME, output);
  }

  @Override
  protected void onActivityResult(int requestCode, int resultCode,
                                  Intent data) {
    if (requestCode == CONTENT_REQUEST) {
      if (resultCode == RESULT_OK) {
        Intent i=new Intent(Intent.ACTION_VIEW);

        i.setDataAndType(outputUri, "image/jpeg");
        i.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
        startActivity(i);
        finish();
      }
    }
  }
}

某些设备的Android相机意图问题

1 个答案: