在android中从图库和摄像头抓取图像

Question

首先，我知道这是一个重复的问题，但我在从画廊或相机捕捉图像时没有问题。我创建了虚拟项目来检查我的代码，在这里它工作得很好，但是当我在我的项目中使用相同的代码时，它不工作，即使我一开始活动结果就没有得到任何错误，它被取消了，但是我仍然可以看到图库中的图像&我可以从相机中捕捉图像。

当我检查logcat时，我发现了以下警告，不知道它为什么会出现，以及我如何解决这个问题

 W/NetworkConnectivityListener(2399): onReceived() called with CONNECTED and Intent { act=android.net.conn.CONNECTIVITY_CHANGE flg=0x10000000 (has extras) }

编辑：--添加代码

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        case R.id.camera:
            //define the file-name to save photo taken by Camera activity
            String fileName = "new-photo-name.jpg";
            //create parameters for Intent with filename
            ContentValues values = new ContentValues();
            values.put(MediaStore.Images.Media.TITLE, fileName);
            values.put(MediaStore.Images.Media.DESCRIPTION,"Image capture by camera");
            //imageUri is the current activity attribute, define and save it for later usage (also in onSaveInstanceState)
            imageUri = getContentResolver().insert(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, values);
            //create new Intent
            Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
            intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
            intent.putExtra(MediaStore.EXTRA_VIDEO_QUALITY, 1);
            startActivityForResult(intent, PICK_Camera_IMAGE);
            return true;

        case R.id.gallery:
            try {
                Intent gintent = new Intent();
                gintent.setType("image/*");
                gintent.setAction(Intent.ACTION_GET_CONTENT);
                startActivityForResult(
                        Intent.createChooser(gintent, "Select Picture"),
                        PICK_IMAGE);
            } catch (Exception e) {
                Toast.makeText(getApplicationContext(),
                        e.getMessage(),
                        Toast.LENGTH_LONG).show();
                Log.e(e.getClass().getName(), e.getMessage(), e);
            }
            return true;
    }
    return false;
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    switch (requestCode) {
            case PICK_IMAGE:
                if (resultCode == Activity.RESULT_OK) {
                    Uri selectedImageUri = data.getData();
                    String filePath = null;

                    try {
                        // OI FILE Manager
                        String filemanagerstring = selectedImageUri.getPath();

                        // MEDIA GALLERY
                        String selectedImagePath = getPath(selectedImageUri);

                        if (selectedImagePath != null) {
                            filePath = selectedImagePath;
                        } else if (filemanagerstring != null) {
                            filePath = filemanagerstring;
                        } else {
                            Toast.makeText(getApplicationContext(), "Unknown path",
                                    Toast.LENGTH_LONG).show();
                            Log.e("Bitmap", "Unknown path");
                        }

                        if (filePath != null) {
                            decodeFile(filePath);
                        } else {
                            bitmap = null;
                        }
                    } catch (Exception e) {
                        Toast.makeText(getApplicationContext(), "Internal error",
                                Toast.LENGTH_LONG).show();
                        Log.e(e.getClass().getName(), e.getMessage(), e);
                    }
                }
                break;
            case PICK_Camera_IMAGE:
                 if (resultCode == RESULT_OK) {
                    //use imageUri here to access the image
                    Toast.makeText(this, "Picture was taken", Toast.LENGTH_SHORT).show();
                    Uri selectedImageUri = imageUri;
                    String filePath = null;

                    try {
                        // OI FILE Manager
                        String filemanagerstring = selectedImageUri.getPath();

                        // MEDIA GALLERY
                        String selectedImagePath = getPath(selectedImageUri);

                        if (selectedImagePath != null) {
                            filePath = selectedImagePath;
                        } else if (filemanagerstring != null) {
                            filePath = filemanagerstring;
                        } else {
                            Toast.makeText(getApplicationContext(), "Unknown path",
                                    Toast.LENGTH_LONG).show();
                            Log.e("Bitmap", "Unknown path");
                        }

                        if (filePath != null) {
                            decodeFile(filePath);
                        } else {
                            bitmap = null;
                        }
                    } catch (Exception e) {
                        Toast.makeText(getApplicationContext(), "Internal error",
                                Toast.LENGTH_LONG).show();
                        Log.e(e.getClass().getName(), e.getMessage(), e);
                    }
                } else if (resultCode == RESULT_CANCELED) {
                    Toast.makeText(this, "Picture was not taken", Toast.LENGTH_SHORT).show();
                } else {
                    Toast.makeText(this, "Picture was not taken", Toast.LENGTH_SHORT).show();
                }
                 break;
        }
}

谢谢

Answer 1

看看我的项目Linderdaum Engine中的LinderdaumEngineActivity.java

从摄像头获取图像：

public void CapturePhoto( String FileName )
{
    try
    {
        File f = new File(FileName);

        if ( f.exists() && f.canWrite() ) f.delete();

        Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        intent.putExtra(android.provider.MediaStore.EXTRA_OUTPUT,Uri.fromFile(f));
        intent.putExtra(MediaStore.EXTRA_VIDEO_QUALITY, 1);

        startActivityForResult(intent, CAPTURE_IMAGE_CALLBACK);
    }
    catch ( ActivityNotFoundException e )
    {
        Log.e( TAG, "No camera: " + e );
    }
    catch ( Exception e )
    {
        Log.e( TAG, "Cannot make photo: " + e );
    }
}

打开图库中的图像：

public static void OpenImage()
{
    try
    {
        Intent intent = new Intent( Intent.ACTION_GET_CONTENT );
        intent.setType( "image/*" );
        startActivityForResult( intent, SELECT_PICTURE_CALLBACK );
    }
    catch ( ActivityNotFoundException e )
    {
        Log.e( TAG, "No gallery: " + e );
    }
}

此外，不要忘记向您的清单添加权限：

<uses-feature android:name="android.hardware.camera" android:required="false"/>
<uses-permission android:name="android.permission.CAMERA" android:required="false"/>

Answer 2

请检查您的AndroidManifest，确保您拥有所有正确的权限。

Answer 3

请参阅android 7以上版本的文件提供程序的官方文档

getUriForFile(Context, String, File) which returns a content:// URI. For 
more recent apps targeting Android 7.0 (API level 24) and higher, passing a 
file:// URI across a package boundary causes a FileUriExposedException. 
Therefore, we now present a more generic way of storing images using a 
FileProvider.



 <application>
 ...
 <provider
    android:name="android.support.v4.content.FileProvider"
    android:authorities="com.example.android.fileprovider"
    android:exported="false"
    android:grantUriPermissions="true">
    <meta-data
        android:name="android.support.FILE_PROVIDER_PATHS"
        android:resource="@xml/file_paths"></meta-data>
 </provider>
...

Official doc