Question

我在我的应用程序中创建了一个从相机拍照的课程。该课程将用相机拍照并将其存储在具有唯一名称的文件夹中。但是，当我想在onActivityResult方法中获取图片路径时，我始终会data为空！

这是我的班级相机：

public class Camera{

  private Activity activity;
  private SystemTools systemTools;


  public Camera(Context context) {

    this.activity = (Activity) context;
    systemTools = new SystemTools();
  }

  /**
   * This Method will take a picture with camera for us
   */

  public void takePicture() {

    boolean cameraAvailable = systemTools.device_isHardwareFeatureAvailable(activity, PackageManager.FEATURE_CAMERA);

    if (cameraAvailable &&
      systemTools.system_isIntentAvailable(activity, MediaStore.ACTION_IMAGE_CAPTURE)) {

      Intent takePicIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

      //We prepare the intent to store the taken picture
      try {

        File outputDir = systemTools.storage_getExternalPublicFolder("ReportsAttachments", true);
        File outFile = systemTools.storage_createUniqueFileName("cameraPic", ".jpg", outputDir);

        takePicIntent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(outFile));

      } catch (Exception e) {
        Toast.makeText(activity, "در دریافت تصویر اشکالی رخ داده است ، لطفا دوباره تلاش کنید.", Toast.LENGTH_SHORT).show();
      }

      activity.startActivityForResult(takePicIntent, App.REQUEST_IMAGE_CAPTURE);


    } else {
      if (cameraAvailable) {
        Toast.makeText(activity, "برنامه ی دوربین دستگاه خراب است.", Toast.LENGTH_SHORT).show();

      } else {
        Toast.makeText(activity, "دسترسی به دوربین سیستم امکان پذیر نمی باشد.", Toast.LENGTH_SHORT).show();
      }
    }
  }
}

在我使用相机的Activity中设置onActivityResult()方法。像这样：

 @Override
  public void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    try {
      if (requestCode == App.REQUEST_IMAGE_CAPTURE) {
        if (resultCode == Activity.RESULT_OK && data != null) {
          Log.i("ATTACH", "In Result");

          Bitmap bmp = (Bitmap) data.getExtras().get("data");
          ByteArrayOutputStream stream = new ByteArrayOutputStream();

          // CALL THIS METHOD TO GET THE URI FROM THE BITMAP
          Uri selectedImage = getImageUri(this, bmp);
          String realPath = getRealPathFromURI(selectedImage);
          selectedImage = Uri.parse(realPath);
          presenter.onNewAttachmentRequest(selectedImage.getPath());


        }
      }
    } catch (Exception e) {
      Log.i("ATTACH", e + "  Something went wrong");
    }
  }

这个工作正常并且在SD_Card上可以使用pictre但是当我想获得图片的路径时我不能因为onActivityResult中的“数据”始终为空！这段代码的问题在哪里？

谢谢。

Answer 1

takePicIntent.putExtra（MediaStore.EXTRA_OUTPUT，Uri.fromFile（outFile））;

如您所见，您已将File Uri传递给intent，即Camera应用程序将在此路径上写入拍摄的图像，并且不会返回Bitmap。只需将此路径保存为类中的全局路径，并在onActivityResult（）中使用它。您还需要添加此选项，因为相机应用程序取决于设备。

takePicIntent.putExtra（＆＃34; return-data＆＃34;，false）;

Answer 2

当我想要获得图片路径时

你已经拥有了图片的路径。它是outFile。将其保存在字段中，并在配置更改中保留它。另外，由于Uri.fromFile()无法在Android 7.0+上运行，因此请考虑切换到FileProvider，就像我在this sample project的以下活动中一样：

/***
 Copyright (c) 2008-2017 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.

 Covered in detail in the book _The Busy Coder's Guide to Android Development_
 https://commonsware.com/Android
 */

package com.commonsware.android.camcon;

import android.Manifest;
import android.app.Activity;
import android.content.ActivityNotFoundException;
import android.content.ClipData;
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 android.widget.Toast;
import java.io.File;
import java.util.List;

public class MainActivity 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;

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

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

      if (output.exists()) {
        output.delete();
      }
      else {
        output.getParentFile().mkdirs();
      }

      Intent i=new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
      Uri outputUri=FileProvider.getUriForFile(this, AUTHORITY, output);

      i.putExtra(MediaStore.EXTRA_OUTPUT, outputUri);

      if (Build.VERSION.SDK_INT>=Build.VERSION_CODES.LOLLIPOP) {
        i.addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
      }
      else if (Build.VERSION.SDK_INT>=Build.VERSION_CODES.JELLY_BEAN) {
        ClipData clip=
          ClipData.newUri(getContentResolver(), "A photo", outputUri);

        i.setClipData(clip);
        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);
        }
      }

      try {
        startActivityForResult(i, CONTENT_REQUEST);
      }
      catch (ActivityNotFoundException e) {
        Toast.makeText(this, R.string.msg_no_camera, Toast.LENGTH_LONG).show();
        finish();
      }
    }
    else {
      output=(File)savedInstanceState.getSerializable(EXTRA_FILENAME);
    }
  }

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

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

        try {
          startActivity(i);
        }
        catch (ActivityNotFoundException e) {
          Toast.makeText(this, R.string.msg_no_viewer, Toast.LENGTH_LONG).show();
        }

        finish();
      }
    }
  }
}

通过从相机

2 个答案: