I modify from tutorial Android Upload Image to Server using Volley Tutorial
in this tutorial, when user select an image, the script directly upload to server. so I modify that when the user select an image, the image display first on imageview, and then, when user click "sendtoserver" button, that image will send to server with the other EditText.
first, I have finish with choose image button, and the image that I choose is showing on imageview.
second, when I click the "sendtoserver" button, I got error about getContentResolver(), here my MainActivity Code
package com.example.celmira.uploadgambar;
import android.Manifest;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.provider.MediaStore;
import android.provider.Settings;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.View;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;
import com.android.volley.AuthFailureError;
import com.android.volley.NetworkResponse;
import com.android.volley.Request;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.Volley;
import com.squareup.picasso.Picasso;
import org.json.JSONException;
import org.json.JSONObject;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
public class MainActivity extends AppCompatActivity {
//ImageView to display image selected
ImageView imageView;
//edittext for getting the tags input
EditText editTextTags;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
//initializing views
imageView = (ImageView) findViewById(R.id.imageView);
editTextTags = (EditText) findViewById(R.id.editTextTags);
//mengecek permission, jika blm diijinkan, maka buka setting atau keluar apps
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && ContextCompat.checkSelfPermission(this,
Manifest.permission.READ_EXTERNAL_STORAGE)
!= PackageManager.PERMISSION_GRANTED) {
Intent intent = new Intent(Settings.ACTION_APPLICATION_DETAILS_SETTINGS, Uri.parse("package:" + getPackageName()));
finish();
startActivity(intent);
return;
}
//get image from gallery when clicked
findViewById(R.id.buttonUploadImage).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//if the tags edittext is empty
//we will throw input error
if (editTextTags.getText().toString().trim().isEmpty()) {
editTextTags.setError("Enter tags first");
editTextTags.requestFocus();
return;
}
//if everything is ok we will open image chooser
Intent i = new Intent(Intent.ACTION_PICK, MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(i, 100);
}
});
// SENDING IMAGE AND TAG TO SERVER WHEN BUTTON sendtoserver clicked
findViewById(R.id.sendtoserver).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Uri imageUri = getIntent().getData();
try {
//getting bitmap object from uri
Bitmap bitmap = MediaStore.Images.Media.getBitmap(getContentResolver(), imageUri);
Log.d("eek",bitmap.toString());
//function to send to server
uploadBitmap(bitmap);
} catch (IOException e) {
e.printStackTrace();
}
}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == 100 && resultCode == RESULT_OK && data != null) {
//getting the image Uri
Uri imageUri = data.getData();
try {
//getting bitmap object from uri
Bitmap bitmap = MediaStore.Images.Media.getBitmap(this.getContentResolver(), imageUri);
//displaying selected image to imageview
Picasso.get().load(imageUri).into(imageView);
} catch (IOException e) {
e.printStackTrace();
}
}
}
/*
* The method is taking Bitmap as an argument
* then it will return the byte[] array for the given bitmap
* and we will send this array to the server
* here we are using PNG Compression with 80% quality
* you can give quality between 0 to 100
* 0 means worse quality
* 100 means best quality
* */
public byte[] getFileDataFromDrawable(Bitmap bitmap) {
ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.PNG, 80, byteArrayOutputStream);
return byteArrayOutputStream.toByteArray();
}
private void uploadBitmap(final Bitmap bitmap) {
//getting the tag from the edittext
final String tags = editTextTags.getText().toString().trim();
//our custom volley request
VolleyMultipartRequest volleyMultipartRequest = new VolleyMultipartRequest(Request.Method.POST, "http://192.168.166.2/MyApi/Api.php?apicall=uploadpic",
new Response.Listener<NetworkResponse>() {
@Override
public void onResponse(NetworkResponse response) {
try {
JSONObject obj = new JSONObject(new String(response.data));
Toast.makeText(getApplicationContext(), obj.getString("message"), Toast.LENGTH_SHORT).show();
} catch (JSONException e) {
e.printStackTrace();
}
}
},
new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(getApplicationContext(), error.getMessage(), Toast.LENGTH_SHORT).show();
}
}) {
/*
* If you want to add more parameters with the image
* you can do it here
* here we have only one parameter with the image
* which is tags
* */
@Override
protected Map<String, String> getParams() throws AuthFailureError {
Map<String, String> params = new HashMap<>();
params.put("tags", tags);
return params;
}
/*
* Here we are passing image by renaming it with a unique name
* */
@Override
protected Map<String, DataPart> getByteData() {
Map<String, DataPart> params = new HashMap<>();
long imagename = System.currentTimeMillis();
params.put("pic", new DataPart(imagename + ".png", getFileDataFromDrawable(bitmap)));
return params;
}
};
//adding the request to volley
Volley.newRequestQueue(this).add(volleyMultipartRequest);
}
}
and here the script that causing error
Bitmap bitmap = MediaStore.Images.Media.getBitmap(getContentResolver(), imageUri);
and this is what error message
FATAL EXCEPTION: main
java.lang.NullPointerException
at android.content.ContentResolver.openInputStream(ContentResolver.java:481)
at android.provider.MediaStore$Images$Media.getBitmap(MediaStore.java:792)
at com.example.celmira.uploadgambar.MainActivity$2.onClick(MainActivity.java:94)
how to getContentResolver() that I can pass to MediaStore.Images.Media.getBitmap()
For upload after select iamge:
Move uploadBitmap(bitmap); to onActivityResult()
For upload after click button:
First create global image url
private Uri imageUri;
In above of your code
Fill it in onActivityResult like you do
imageUri = data.getData();
And send it when call button
findViewById(R.id.sendtoserver).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//THIS LINE REMOVED
//Uri imageUri = getIntent().getData();
try {
//getting bitmap object from uri
Bitmap bitmap = MediaStore.Images.Media.getBitmap(getContentResolver(), imageUri);
Log.d("eek",bitmap.toString());
//function to send to server
uploadBitmap(bitmap);
} catch (IOException e) {
e.printStackTrace();
}
}
});