我正在创建一个应用程序，其中用户可以将图像和视频上传到服务器 它在活动上运作良好，但现在我想在一个片段中使用它。我尝试有效，高效地编码，我在编译期间没有收到任何错误，我的应用程序运行成功但是当我点击片段时它显示＆＃34;不幸的是应用程序停止了＃34;并在log cat中我收到此错误：
java.lang.NullPointerException：尝试调用虚拟方法＆android; .and.ar。在空对象引用上
并指出这一行：
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
this line ➦ fileUri = savedInstanceState.getParcelable("file_uri");
}
我不知道什么是错的
我的代码：
public class TabFragment4 extends Fragment implements View.OnClickListener{
View parentHolder;
private static final String TAG = MainActivity.class.getSimpleName();
int req_code = 100;
int video_code = 20;
String path;
Uri selectedImageUri;
// Camera activity request codes
private static final int CAMERA_CAPTURE_IMAGE_REQUEST_CODE = 10;
private static final int CAMERA_CAPTURE_VIDEO_REQUEST_CODE = 200;
public static final int MEDIA_TYPE_IMAGE = 1;
public static final int MEDIA_TYPE_VIDEO = 2;
Context mContext;
private Uri fileUri; // file url to store image/video
private ImageButton btnCapturePicture, btnRecordVideo,gallerybtn , videobtn,b1,location;
public TabFragment4() {
// Required empty public constructor
}
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
parentHolder = inflater.inflate(R.layout.fragment_tab_fragment4, container, false);
final LocationManager manager = (LocationManager) getActivity().getSystemService(Context.LOCATION_SERVICE);
if ( !manager.isProviderEnabled( LocationManager.GPS_PROVIDER ) ) {
AlertDialog.Builder mAlertDialog = new AlertDialog.Builder(getActivity());
// Setting Dialog Title
mAlertDialog.setTitle("Location not available, Open GPS?")
.setMessage("Activate GPS to use Location Service ?")
.setPositiveButton("Open Settings", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
startActivity(intent);
}
})
.setNegativeButton("Cancel",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.cancel();
}
}).show();
// Call your Alert message
}
btnCapturePicture = (ImageButton)parentHolder.findViewById(R.id.btnCapturePicture);
btnRecordVideo = (ImageButton)parentHolder. findViewById(R.id.btnRecordVideo);
gallerybtn=(ImageButton)parentHolder.findViewById(R.id.imagegallery);
videobtn = (ImageButton)parentHolder.findViewById(R.id.videogallery);
location=(ImageButton)parentHolder.findViewById(R.id.location);
videobtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
video();
}
});
gallerybtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// record video
galleryimage();
}
});
btnCapturePicture.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// record video
captureImage();
}
});
/**
* Capture image button click event
*/
btnRecordVideo.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// record video
recordVideo();
}
});
/**
* Record video button click event
*/
btnRecordVideo.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// record video
recordVideo();
}
});
return parentHolder;
}
public void video(){
Intent intent = new Intent();
intent.setType("video/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent,
"Select file to upload "), video_code);
}
public void galleryimage(){
Intent intent = new Intent();
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent,
"Select file to upload "), req_code);
}
public String getPath(Uri uri) {
String[] projection = { MediaStore.Images.Media.DATA };
Cursor cursor = getActivity().managedQuery(uri, projection, null, null, null);
int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
return cursor.getString(column_index);
}
private void captureImage() {
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
fileUri = getOutputMediaFileUri(MEDIA_TYPE_IMAGE);
intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);
// start the image capture Intent
startActivityForResult(intent, CAMERA_CAPTURE_IMAGE_REQUEST_CODE);
}
/**
* Launching camera app to record video
*/
private void recordVideo() {
Intent intent = new Intent(MediaStore.ACTION_VIDEO_CAPTURE);
fileUri = getOutputMediaFileUri(MEDIA_TYPE_VIDEO);
// set video quality
intent.putExtra(MediaStore.EXTRA_VIDEO_QUALITY, 1);
intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri); // set the image file
// name
// start the video capture Intent
startActivityForResult(intent, CAMERA_CAPTURE_VIDEO_REQUEST_CODE);
}
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
// save file url in bundle as it will be null on screen orientation
// changes
outState.putParcelable("file_uri", fileUri);
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
fileUri = savedInstanceState.getParcelable("file_uri");
}
public void onActivityResult(int requestCode, int resultCode, Intent data) {
// if the result is capturing Image
if (requestCode == req_code) {
selectedImageUri = data.getData();
if (resultCode ==Activity. RESULT_OK) {
path = getPath(selectedImageUri);
launchUpload(true);
System.out.println("selectedPath1 : " + path);
}
}
if (requestCode == video_code) {
selectedImageUri = data.getData();
if (resultCode == Activity. RESULT_OK) {
path = getPath(selectedImageUri);
launchUpload(false);
System.out.println("selectedPath1 : " + path);
}
}
if (requestCode == CAMERA_CAPTURE_IMAGE_REQUEST_CODE) {
if (resultCode == Activity.RESULT_OK) {
//successfully captured the image
// launching upload activity
launchUploadActivity(true);
//Intent intent = new Intent(this,UploadActivity.class);
//startActivity(intent);
} else if (resultCode ==Activity. RESULT_CANCELED) {
// user cancelled Image capture
Toast.makeText(getActivity(),
"User cancelled image capture", Toast.LENGTH_SHORT)
.show();
} else {
// failed to capture image
Toast.makeText(getActivity(),
"Sorry! Failed to capture image", Toast.LENGTH_SHORT)
.show();
}
} else if (requestCode == CAMERA_CAPTURE_VIDEO_REQUEST_CODE) {
if (resultCode == Activity.RESULT_OK) {
// video successfully recorded
// launching upload activity
launchUploadActivity(false);
} else if (resultCode == Activity.RESULT_CANCELED) {
// user cancelled recording
Toast.makeText(getActivity(),
"User cancelled video recording", Toast.LENGTH_SHORT)
.show();
} else {
// failed to record video
Toast.makeText(getActivity(),
"Sorry! Failed to record video", Toast.LENGTH_SHORT)
.show();
}
}
}
private void launchUploadActivity(boolean isImage) {
Intent i = new Intent(getActivity(), UploadActivity.class);
i.putExtra("filePath", fileUri.getPath());
i.putExtra("isImage", isImage);
startActivity(i);
}
private void launchUpload(boolean isImage) {
Intent i = new Intent(getActivity(), UploadActivity.class);
i.putExtra("filePath", path);
i.putExtra("isImage", isImage);
startActivity(i);
}
/**
* ------------ Helper Methods ----------------------
* */
/**
* Creating file uri to store image/video
*/
public Uri getOutputMediaFileUri(int type) {
return Uri.fromFile(getOutputMediaFile(type));
}
/**
* returning image / video
*/
private static File getOutputMediaFile(int type) {
// External sdcard location
File mediaStorageDir = new File(
Environment
.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES),
Config.IMAGE_DIRECTORY_NAME);
// Create the storage directory if it does not exist
if (!mediaStorageDir.exists()) {
if (!mediaStorageDir.mkdirs()) {
Log.d(TAG, "Oops! Failed create "
+ Config.IMAGE_DIRECTORY_NAME + " directory");
return null;
}
}
// Create a media file name
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss",
Locale.getDefault()).format(new Date());
File mediaFile;
if (type == MEDIA_TYPE_IMAGE) {
mediaFile = new File(mediaStorageDir.getPath() + File.separator
+ "IMG_" + timeStamp + ".jpg");
} else if (type == MEDIA_TYPE_VIDEO) {
mediaFile = new File(mediaStorageDir.getPath() + File.separator
+ "VID_" + timeStamp + ".mp4");
} else {
return null;
}
return mediaFile;
}
@Override
public void onClick(View v) {
}
}
答案 0 :(得分：2)
Uri imageUri = data.getData();
Bitmap bitmap= null;
try {
bitmap = MediaStore.Images.Media.getBitmap(getContext().getContentResolver(), imageUri);
} catch (IOException e) {
e.printStackTrace();
}
答案 1 :(得分：1)
似乎savedInstanceState == null所以请使用以下内容：
if (savedInstanceState != null) {
fileUri = savedInstanceState.getParcelable("file_uri");
} else {
fileUri = ??? - what You want do to in else case;
}