Develop Reference

How to start gallery app from an android app?

I am trying to open the gallery app from my android application. I want to just open the gallery app and not other apps with like fotos.
I have tried
intent.setAction(Intent.ACTION_GET_CONTENT);
intent.setType("image/*");
and
intent.setAction(android.content.Intent.ACTION_VIEW);
intent.setType("image/*");
and
intent = new Intent(
Intent.ACTION_PICK,
android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
The problem is that all this show a dialog where I can pick again from all apps that have images. So it shows a dialog with "Gallery", "Fotos", etc....
Is there a possibility to open just one app, without having to chose again?

EDIT: If you want to use the gallery API, which does show photos from all photo apps on the phone and which is not a standalone user-accessible app itself, you could use this code:
private static final int PICK_IMAGE = 100;
private ImageView imageView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_image_picker);
imageView = (ImageView) findViewById(R.id.image_view);
Button pickImageButton = (Button) findViewById(R.id.pick_button);
pickImageButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
openGallery();
}
});
}
private void openGallery() {
Intent gallery =
new Intent(Intent.ACTION_PICK,
android.provider.MediaStore.Images.Media.INTERNAL_CONTENT_URI);
startActivityForResult(gallery, PICK_IMAGE);
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_OK && requestCode == PICK_IMAGE) {
Uri imageUri = data.getData();
imageView.setImageURI(imageUri);
}
}
}
Unfortunately, I don't believe choosing photos from a specific app is possible, as "the gallery app" that comes installed on devices varies by manufacturer and OS skin. For example, the default gallery on Pixel devices is actually Google Photos.
If I misunderstood, and you do want to simply launch the Gallery app, you can include the following code in your /src/[ActivityName].java file:
package com.example.andy.myapplication;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.LinearLayout;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
int view = R.layout.activity_main;
TextView textView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(view);
final LinearLayout parent = findViewById(R.id.parent);
textView = findViewById(R.id.text);
textView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent launchIntent = getPackageManager().getLaunchIntentForPackage("com.sec.android.gallery3d");
if (launchIntent != null) {
startActivity(launchIntent);
} else {
Toast.makeText(MainActivity.this, "There is no package available in android", Toast.LENGTH_LONG).show();
}
}
});
}
}
Notice that the app being opened is Gallery, the default Samsung photo gallery app. If you want to replace this with Google Photos, you would replace com.sec.android.gallery3d with com.google.android.apps.photos.

SAF - listening to events from a folder in the cloud

I am experimenting with Storage Access Framework, because I would like to improve my app, that has migrated to SAF already (although I had to surrender some features because of some SAF design flaws or maybe bugs).
Now I want that my app is notified when the user does something in a SAF folder in the cloud.
At present time it is purely experimental because it is by hack that it is possible to have the uri of a cloud folder by GDrive.
(the other cloud providers seem not to be SAF ready, please correct me if I am wrong)
I am just working in advance before they release the full feature (there is a bugfix request about that) to be able to select a folder on a cloud storage root in the system picker.
I created a simple application for creating a SAF folder on the cloud (selection is not possible at present time on cloud storage) and listening to events.
package com.example.safevents;
import android.app.Activity;
import android.content.Intent;
import android.database.ContentObserver;
import android.net.Uri;
import android.os.Bundle;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
import com.google.android.material.snackbar.Snackbar;
import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.Toolbar;
import android.os.Handler;
import android.util.Log;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
public class MainActivity extends AppCompatActivity {
Activity activity;
Handler handler;
Observer observer;
class Observer extends ContentObserver {
public Observer(Handler handler) {
super(handler);
}
#Override
public void onChange(boolean selfChange) {
this.onChange(selfChange, null);
Log.d("SAF","event fired; selfchange="+selfChange);
}
#Override
public void onChange(boolean selfChange, Uri uri) {
Log.d("SAF","event fired on uri="+uri.toString()+"; selfchange="+selfChange);
}
}
public void openPickerForFolderCreation(Activity activity, int requestCode) {
Intent intent = new Intent(Intent.ACTION_CREATE_DOCUMENT);
intent.setType("vnd.android.document/directory");
intent.addFlags(Intent.FLAG_GRANT_PERSISTABLE_URI_PERMISSION);
intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
intent.addFlags(Intent.FLAG_GRANT_WRITE_URI_PERMISSION);
activity.startActivityForResult(intent, requestCode);
}
public Uri takePermanentReadWritePermissions(Activity activity, Uri uri, int flags) {
int takeFlags = flags
&
(Intent.FLAG_GRANT_READ_URI_PERMISSION | Intent.FLAG_GRANT_WRITE_URI_PERMISSION
);
;
ContentResolver resolver = activity.getContentResolver();
resolver.takePersistableUriPermission(uri, takeFlags);
return uri;
}
public boolean arePermissionsGranted(Activity activity, String uriString) {
Uri uri = Uri.parse(uriString);
ContentResolver resolver = activity.getContentResolver();
List<UriPermission> list = resolver.getPersistedUriPermissions();
for (int i = 0; i < list.size(); i++) {
if (((Uri.decode(list.get(i).getUri().toString())).equals(Uri.decode(uriString))) && list.get(i).isWritePermission() && list.get(i).isReadPermission()) {
return true;
}
}
return false;
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
activity=this;
FloatingActionButton fab = findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
SAFUtils.openPickerForFolderCreation(activity,0);
}
});
}
#Override
protected void onDestroy()
{
super.onDestroy();
//important
getContentResolver().unregisterContentObserver(observer);
}
#Override
protected void onActivityResult(int requestCode, int resultCode,Intent returnedIntent)
{
Log.d("SAF","picker returned "+resultCode+" "+requestCode);
if (returnedIntent!=null) Log.d("SAF","intent="+returnedIntent.toString());
if (returnedIntent.getData()!=null) Log.d("SAF","uri="+returnedIntent.getData().toString());
//resultCode is -1
if (resultCode==-1)
if (requestCode==0)
{
Uri uri=SAFUtils.takePermanentReadWritePermissions(activity,returnedIntent.getData(),returnedIntent.getFlags());
Log.d("SAF","read/write permissions="+SAFUtils.arePermissionsGranted(activity,uri.toString()));
handler=new Handler(){};
observer=new Observer(handler);
getContentResolver().
registerContentObserver(
uri,
true,
observer);
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
I get this log lines:
com.example.safevents D/SAF: picker returned -1 0
com.example.safevents D/SAF: intent=Intent { dat=content://com.google.android.apps.docs.storage/document/acc=3;doc=encoded=randomalphanumericsequence= flg=0x43 }
com.example.safevents D/SAF: uri=content://com.google.android.apps.docs.storage/document/acc%3D3%3Bdoc%3Dencoded%3Dthesamealphanumericsequence%3D
com.example.safevents D/SAF: read/write permissions=true
but I do not receive any event notifications after some simple file operations inside the created folder.
Note that resultCode= -1.
Also note that omitting the call to the takePersistentPermissions method leads to no permissions, resulting from the utility function that check them not finding the uri in the list.
Is there something wrong in the code above?
Is the creation of SAF cloud folder such a hack that it does not work?
Is a further hack possible to force this to work so to be tested roughly in advance?
Is that SAF functionality not available at present time?

FileObserver not working with intent

I need to use camera intent and keep track of the new images taken by the intent. As I need to take multiple photos at a time, I used the intent MediaStore.INTENT_ACTION_STILL_IMAGE_CAMERA. Here is my code:
package com.arko.cameraintent;
import android.content.Intent;
import android.os.Environment;
import android.provider.MediaStore;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Toast;
import java.io.File;
public class CameraMainActivity extends AppCompatActivity {
private static final int REQ_CODE = 0;
AppCompatActivity main_activity = this; // save it for future use
DirectoryFileObserver directoryFileObserver;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_camera_main);
}
public void takePhoto(View view) // fired when a button in the main application is clicked. This starts the camera application.
{
Intent callCamAppIntent = new Intent();
callCamAppIntent.setAction(MediaStore.INTENT_ACTION_STILL_IMAGE_CAMERA);
String dir = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM).getAbsolutePath();
Toast.makeText(this, dir, Toast.LENGTH_SHORT).show();
directoryFileObserver = new DirectoryFileObserver(dir);
directoryFileObserver.startWatching();
startActivityForResult(callCamAppIntent, REQ_CODE);
}
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if(requestCode == REQ_CODE){
Toast.makeText(this, "picture taken successfully", Toast.LENGTH_SHORT).show();
directoryFileObserver.stopWatching();
}
}
}
The code of DirectoryFileObserver class:
package com.arko.cameraintent;
import android.os.AsyncTask;
import android.os.Environment;
import android.os.FileObserver;
import android.support.annotation.Nullable;
import java.io.File;
public class DirectoryFileObserver extends FileObserver {
String rootDir;
static final int mask = (FileObserver.CREATE | FileObserver.MODIFY | FileObserver.DELETE);
public final String DIRECTORY_NAME = "Simplified Intent";
public DirectoryFileObserver(String path) {
super(path, mask);
rootDir = path;
}
#Override
public void onEvent(int event, #Nullable String path) {
switch(event){
case FileObserver.CREATE:
String outputDir = Environment.getExternalStorageDirectory().getAbsolutePath() + File.separator +
Environment.DIRECTORY_PICTURES +
File.separator + DIRECTORY_NAME;
// do something here
break;
case FileObserver.MODIFY:
// will be implemented later
break;
case FileObserver.DELETE:
// will be implemented later
break;
}
}
}
But the onEvent function never gets executed, as suggested by Debug. What is the reason behind it? I have even changed the default save location of the camera application to Internal Storage (initially it was set to SD card) and ran my app again, but nothing changed. I have mentioned both READ_EXTERNAL_STORAGE and WRITE_EXTERNAL_STORAGE permissions in the manifest file.

How to record and save a video using Google Glass

I am fairly new to android studio and developing with android. I have been trying this for months now, I need to record and save a video using Google Glass. The code that I currently have follows. This is code inspired from https://developers.google.com/glass/develop/gdk/camera#images
When I run this process, the video will start recording and then when the recording is stopped, it will give me the option "tap to accept" When I tap, nothing happens. I understand this is because my method "processVideoWhenReady" does absolutely nothing.
I would like to know if anyone could help me with what I should include in that method to save the video and allow it to be viewed by the user within my application.
Any literature or websites that have useful information about developing for Google Glass would also be a huge help if possible. Google's documentation doesn't seem very helpful to me and very limited.
import android.app.Activity;
import android.graphics.Camera;
import android.media.CamcorderProfile;
import android.media.MediaRecorder;
import android.net.Uri;
import android.os.Bundle;
import android.content.Intent;
import android.os.FileObserver;
import android.provider.MediaStore;
import android.util.Log;
import android.widget.VideoView;
import com.google.android.glass.content.Intents;
import com.google.android.glass.widget.CardBuilder;
import java.io.File;
import java.io.IOException;
public class RecordActivity extends Activity {
private static final int CAMERA_VID_REQUEST = 1337;
static final int REQUEST_VIDEO_CAPTURE = 1;
public VideoView mVideoView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//setContentView(R.layout.activity_record);
takeVideo();
}
private void takeVideo(){
Intent startVideo = new Intent(MediaStore.ACTION_VIDEO_CAPTURE);
if (startVideo.resolveActivity(getPackageManager()) != null){
startActivityForResult(startVideo, REQUEST_VIDEO_CAPTURE);
}
//RecordActivity.this.startActivityForResult(startVideo, CAMERA_VID_REQUEST);
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data){
//System.out.println("Entered onActivityResult() method");
String a = getIntent().getStringExtra("record");
System.out.println(a);
if(requestCode == CAMERA_VID_REQUEST && resultCode == RESULT_OK) {
//System.out.println("Result Okay");
Uri videoUri = data.getData();
mVideoView.setVideoURI(videoUri);
String videoPath = data.getStringExtra(Intents.EXTRA_VIDEO_FILE_PATH);
processVideoWhenReady(videoPath);
}
super.onActivityResult(requestCode, resultCode, data);
}
protected void processVideoWhenReady(final String videoPath){
final File videoFile = new File(videoPath);
if (videoFile.exists()){
//Process Video
}
else {
final File parentDirectory = videoFile.getParentFile();
FileObserver observer = new FileObserver(parentDirectory.getPath(), FileObserver.CLOSE_WRITE | FileObserver.MOVED_TO) {
private boolean isFileWritten;
#Override
public void onEvent(int event, String path) {
if (!isFileWritten) {
//make sure file was created in directory expected
File affectedFile = new File(parentDirectory, path);
isFileWritten = affectedFile.equals(videoFile);
if (isFileWritten) {
stopWatching();
runOnUiThread(new Runnable() {
#Override
public void run() {
processVideoWhenReady(videoPath);
}
});
}
}
}
};
observer.startWatching();
}
}
}

Android ImageView content disapearing after showing

My application does this: takes a photo, then show the photo in an ImageView. The weird thing is that the photo is displayed for about a second (after taking it with the camera), and then the ImageView is empty again.
This is my code:
publish.xml
<ImageView
android:id="#+id/itemImage"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>
PublishActivity.java
package ar.com.guiagratis;
import java.io.File;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.BitmapDrawable;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.view.View;
import android.widget.ImageView;
import android.widget.Toast;
public class PublishActivity extends Activity {
final int TAKE_PICTURE_REQUEST_CODE = 115;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.publish);
}
public void btnNextClick(View v) {
// TODO: disable all buttons
//Intent intent=new Intent(getApplicationContext(), TakePhotoActivity.class);
// startActivityForResult(intent, TAKE_PICTURE_RESULT_CODE);
Toast.makeText(getApplicationContext(), "Sacate una foto viteh", Toast.LENGTH_SHORT).show();
Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
File photoFile = new File(Environment.getExternalStorageDirectory(), "Photo.png");
Uri imageUri = Uri.fromFile(photoFile);
intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
startActivityForResult(intent, TAKE_PICTURE_REQUEST_CODE);
}
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
switch (requestCode) {
case TAKE_PICTURE_REQUEST_CODE:
if (resultCode == Activity.RESULT_OK) {
File photoFile = new File(Environment.getExternalStorageDirectory(), "Photo.png");
Uri imageUri = Uri.fromFile(photoFile);
// Image captured and saved to fileUri specified in the Intent
Toast.makeText(this, "Image saved to:\n" +
imageUri, Toast.LENGTH_LONG).show();
Bitmap myBitmap = BitmapFactory.decodeFile(imageUri.getPath());
BitmapDrawable ob = new BitmapDrawable(myBitmap);
ImageView myImage = (ImageView) findViewById(R.id.itemImage);
myImage.setBackgroundDrawable(ob);
Toast.makeText(getApplicationContext(), "Qué linda foto! ", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(getApplicationContext(), "Hubo un problema al subir la imágen... ", Toast.LENGTH_SHORT).show();
}
}
}
}
Any help will be appreciated.

You're using setBackgroundDrawable(Drawable drawable) which sets the View's background.
If you want to change the ImageView's content you need to use
setImageDrawable(Drawable drawable)
or
setImageBitmap(Bitmap bm)

Ok, I finally found the problem. I was not aware that I need to use onSaveInstanceState and onRestoreInstanceState to store the values I don't want to loose from an Activity when I'm doing certain things, like initiating the Camera and taking a photo.
So I added this code:
#Override
public void onSaveInstanceState(Bundle savedInstanceState) {
super.onSaveInstanceState(savedInstanceState);
// Save UI state changes to the savedInstanceState.
// This bundle will be passed to onCreate if the process is
// killed and restarted.
savedInstanceState.putBoolean("photoUploaded", photoUploaded);
}
#Override
public void onRestoreInstanceState(Bundle savedInstanceState) {
super.onRestoreInstanceState(savedInstanceState);
// Restore UI state from the savedInstanceState.
// This bundle has also been passed to onCreate.
photoUploaded = savedInstanceState.getBoolean("photoUploaded");
if (photoUploaded) {
File photoFile = new File(Environment.getExternalStorageDirectory(), "Photo.png");
Uri imageUri = Uri.fromFile(photoFile);
Bitmap myBitmap = BitmapFactory.decodeFile(imageUri.getPath());
BitmapDrawable ob = new BitmapDrawable(myBitmap);
ImageView myImage = (ImageView) findViewById(R.id.uploadedImage);
myImage.setBackgroundDrawable(ob);
}
}
and now is working.
Not sure how to do to make this question as solved.