when ever i am not selecting any image after opening the gallery and goin back my app crashes. plz help me out guys. this is a program to upload image to server selecting from a gallery
public class FragmentAskFitindya extends Fragment {
private AskJSON obj;
private EditText subject,question;
private Spinner category;
private TextView messageText,tv;
private CheckBox privacyBox;
private Button uploadButton, btnselectpic,uploadButton2;
private ImageView imageview;
private int serverResponseCode = 0;
private ProgressDialog dialog = null;
public String user_id,sub,quest,cat_id,privacy;
private String upLoadServerUri = null;
private String imagepath=null;
public static final String IMAGE_RESOURCE_ID = "iconResourceID";
public static final String ITEM_NAME = "itemName";
public static String getUrlData= new Sql_connect().url();
public FragmentAskFitindya()
{
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view=inflater.inflate(R.layout.fragment_layout_askfitindya,container, false);
category=(Spinner)view.findViewById(R.id.spinner1);
privacyBox=(CheckBox) view.findViewById(R.id.item_check);
subject=(EditText) view.findViewById(R.id.subject_text);
question=(EditText) view.findViewById(R.id.your_question_text);
uploadButton = (Button)view.findViewById(R.id.uploadButton);
uploadButton2=(Button) view.findViewById(R.id.uploadButton2);
privacyBox=(CheckBox) view.findViewById(R.id.item_check);
btnselectpic = (Button)view.findViewById(R.id.button_selectpic);
imageview = (ImageView)view.findViewById(R.id.imageView_pic);
uploadButton.setVisibility(View.GONE);
btnselectpic.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent();
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent, "Complete action using"), 1);
}
});
uploadButton.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
dialog = ProgressDialog.show(getActivity(), "", "Uploading file...", true);
// messageText.setText("uploading started.....");
new Thread(new Runnable() {
public void run() {
if(privacyBox.isChecked()){
privacy="1";
}
if(privacyBox.isChecked()){
}else{
privacy="0";
}
cat_id=category.getSelectedItem().toString();
if(cat_id.equals("Weight Loss")){
cat_id="1";
}
if(cat_id.equals("Muscle Gain")){
cat_id="2";
}
sub=subject.getText().toString();
quest=question.getText().toString();
upLoadServerUri = getUrlData+"windex.php?itfpage=addquestion" +
"&user_id=3" +
"&subject=" +sub+
"&quest="+quest+
"&cat_id="+cat_id+
"&privacy="+privacy;
uploadFile(imagepath);
}
}).start();
}
});
}
});
return view;
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
//&& resultCode == RESULT_OK
if (requestCode == 1 ) {
//Bitmap photo = (Bitmap) data.getData().getPath();
Uri selectedImageUri = data.getData();
imagepath = getPath(selectedImageUri);
Bitmap bitmap=BitmapFactory.decodeFile(imagepath);
imageview.setImageBitmap(bitmap);
// messageText.setText("Uploading file path:" +imagepath);
}
}
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);
}
public int uploadFile(String sourceFileUri) {
String fileName = sourceFileUri;
HttpURLConnection conn = null;
DataOutputStream dos = null;
String lineEnd = "\r\n";
String twoHyphens = "--";
String boundary = "*****";
int bytesRead, bytesAvailable, bufferSize;
byte[] buffer;
int maxBufferSize = 1 * 1024 * 1024;
File sourceFile = new File(sourceFileUri);
if (!sourceFile.isFile()) {
dialog.dismiss();
Log.e("uploadFile", "Source File not exist :"+imagepath);
getActivity().runOnUiThread(new Runnable() {
public void run() {
// messageText.setText("Source File not exist :"+ imagepath);
Log.v("img path", ""+imagepath);
}
});
return 0;
}
else
{
try {
// open a URL connection to the Servlet
FileInputStream fileInputStream = new FileInputStream(sourceFile);
URL url = new URL(upLoadServerUri);
// Open a HTTP connection to the URL
conn = (HttpURLConnection) url.openConnection();
conn.setDoInput(true); // Allow Inputs
conn.setDoOutput(true); // Allow Outputs
conn.setUseCaches(false); // Don't use a Cached Copy
conn.setRequestMethod("POST");
conn.setRequestProperty("Connection", "Keep-Alive");
conn.setRequestProperty("ENCTYPE", "multipart/form-data");
conn.setRequestProperty("Content-Type", "multipart/form-data;boundary=" + boundary);
conn.setRequestProperty("askimage", fileName);
dos = new DataOutputStream(conn.getOutputStream());
dos.writeBytes(twoHyphens + boundary + lineEnd);
dos.writeBytes("Content-Disposition: form-data; name=\"askimage\";filename=\""
+ fileName + "\"" + lineEnd);
dos.writeBytes(lineEnd);
// create a buffer of maximum size
bytesAvailable = fileInputStream.available();
bufferSize = Math.min(bytesAvailable, maxBufferSize);
buffer = new byte[bufferSize];
// read file and write it into form...
bytesRead = fileInputStream.read(buffer, 0, bufferSize);
while (bytesRead > 0) {
dos.write(buffer, 0, bufferSize);
bytesAvailable = fileInputStream.available();
bufferSize = Math.min(bytesAvailable, maxBufferSize);
bytesRead = fileInputStream.read(buffer, 0, bufferSize);
}
// send multipart form data necesssary after file data...
dos.writeBytes(lineEnd);
dos.writeBytes(twoHyphens + boundary + twoHyphens + lineEnd);
// Responses from the server (code and message)
serverResponseCode = conn.getResponseCode();
String serverResponseMessage = conn.getResponseMessage();
Log.i("uploadFile", "HTTP Response is : "
+ serverResponseMessage + ": " + serverResponseCode);
if(serverResponseCode == 200){
getActivity().runOnUiThread(new Runnable() {
public void run() {
dialog.dismiss();
Toast.makeText(getActivity(), "File Upload Complete.", Toast.LENGTH_SHORT).show();
}
});
}
//close the streams //
fileInputStream.close();
dos.flush();
dos.close();
} catch (MalformedURLException ex) {
dialog.dismiss();
ex.printStackTrace();
getActivity().runOnUiThread(new Runnable() {
public void run() {
messageText.setText("MalformedURLException Exception : check script url.");
Toast.makeText(getActivity(), "MalformedURLException", Toast.LENGTH_SHORT).show();
}
});
Log.e("Upload file to server", "error: " + ex.getMessage(), ex);
} catch (Exception e) {
dialog.dismiss();
e.printStackTrace();
getActivity().runOnUiThread(new Runnable() {
public void run() {
messageText.setText("Got Exception : see logcat ");
// Toast.makeText(getActivity(), "Got Exception : see logcat ", Toast.LENGTH_SHORT).show();
}
});
Log.e("Upload file to server Exception", "Exception : " + e.getMessage(), e);
}
// dialog.dismiss();
return serverResponseCode;
} // End else block
}
}
You can handle it this way:
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == 1 && resultCode == RESULT_OK && data != null) {
//your code
}
else {
//alert of "No image was selected"
}
}
Don't perform any operation on data if its null. So it won't give a crash.
Hope it helps.
Add below line in your code. If the operation is cancelled, you will not get RESULT_OK
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (resultCode != RESULT_OK)
return;
Try this, add if(resultCode == RESULT_OK) :
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if(resultCode == RESULT_OK){ //<-- Add this
if (requestCode == 1 ) {
//Bitmap photo = (Bitmap) data.getData().getPath();
Uri selectedImageUri = data.getData();
imagepath = getPath(selectedImageUri);
Bitmap bitmap=BitmapFactory.decodeFile(imagepath);
imageview.setImageBitmap(bitmap);
// messageText.setText("Uploading file path:" +imagepath);
}
}
}
In your current code , even if the result code is not OK its executing data.getData() which is null
来源：https://stackoverflow.com/questions/26115623/app-crashes-when-going-back-from-gallery-without-selecting-any-image