Back to previous activity in android - java

I have Activity A, B and C. In Activity C, it has an image and caption. The image and caption will be return to B when ok button is clicked. In activity b, it will return both to activity A.
Activity C
ok.setOnClickListener(new View.OnClickListener() // ok button to return image and caption to B
{
public void onClick(View arg0)
{
Intent returnIntent=new Intent();
text=t.getText().toString();
b.setDrawingCacheEnabled(true);
b.measure(View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED),
View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));
b.layout(0, 0, b.getMeasuredWidth(), b.getMeasuredHeight());
b.buildDrawingCache(true);
returnIntent.putExtra("text", text);
if (b.getDrawingCache() != null) {
Bitmap bitmap = Bitmap.createBitmap(b.getDrawingCache());
if (bitmap == null) {
Log.e("TAG", "getDrawingCache() == null");
}
Global.img = bitmap;
}
setResult(Activity.RESULT_OK, returnIntent);
finish();
}
});
Activity B
public void onActivityResult(int requestCode,int resultCode, Intent data)
{
if(requestCode==PROJECT_REQUEST_CODE) {
if(data!=null&&data.hasExtra("text")) {
c = data.getStringExtra("text");
txt1.setText(c); // caption can show in txt1
viewImage.setImageBitmap(Global.img); // image from C can show in viewImage
}
}
else if (requestCode==CAMERA_REQUEST_CODE)
{
}
}
b.setOnClickListener(new View.OnClickListener() { // button to return image and caption to A
public void onClick(View arg0) {
Intent returnIntent = new Intent();
returnIntent.putExtra("c",c); // return caption
returnIntent.putExtra("globalImg",Global.img);
setResult(Activity.RESULT_OK, returnIntent);
finish();
}
});
Activity A
public void onActivityResult(int requestCode, int resultCode, Intent data) {
Bitmap b = Global.img
if (requestCode==1) {
caption = data.getStringExtra("c"); // caption from A
v.setImageBitmap(Global.img) // image from C
}else if {.....}
}
Global.java
public class Global {
static Bitmap img;
}
When I click button b in Activity B, I get this
11-05 17:26:47.114 6031-6031/com.example.project.project
E/JavaBinder﹕ !!! FAILED BINDER TRANSACTION !!!

Provided what you are trying to do is simply to pass along the data returned from C->B on to A, why don't you just get the string again in your onClick and put it into your intent?
You could store the text in a String member, or, as the code looks now, even get it back from the TextView:
Intent returnIntent = new Intent();
returnIntent.putExtra("text", txt1.getText().toString);
setResult(Activity.RESULT_OK, returnIntent);
The image is being stored as a static in a global object, which honestly is horrible, but you could of course access that as well from your onClickListener. You should however seriously consider returning the bitmap data in some other way, the most straightforward probably being utilizing that Bitmaps implement the Parcelable interface, and Intents can hold Parcelables as extras, so in theory you can just do putExtra("img", bitmap) and on the receiving end do intent.getParcelableExtra("img").
However, if the bitmap is large this might fail, and it might be better to store the bitmap to a resource such as a file, and pass the location of the file instead. You may also get a way with something like what you did with your static member in the Global class, but 1) you must be careful to remove the object after passing it back or the static reference will waste memory and 2) make sure you don't use this reference incorrectly, e.g. from multiple places simulatenously. A more robust solution is to make sure you create a unique ID for each bitmap and store it in a cache (for example a HashMap with the Bitmaps hashCode() as the key) and identify it by id.
public class BitmapStore {
private static final HashMap<Integer, Bitmap> BITMAPS= new HashMap<>();
public static Bitmap getBitmap(int id) {
return BITMAPS.remove(id);
}
public static int putBitmap(Bitmap b) {
int id = b.hashCode();
BITMAPS.put(id, b);
return id;
}
}
Using this, you could put the ID of your bitmap in your intent:
intent.putExtra("imageId", BitmapStore.putBitmap(bitmap));
setResult(RESULT_OK, intent);
and in onActivityResult:
Bitmap b = BitmapStore.getBitmap(intent.getIntExtra("imageId", 0));
This bitmap store is not persistant but it should be pretty safe to use as an intermediate store in the transition between two activities. It's also possible to generalize to any kind of object implementing a valid hashCode/equals contract.

try comment this line:
//returnIntent.putExtra("globalImg",Global.img);
in your Activity B
You can use Global.img for all Activity and not use intent
Added:
v.setImageBitmap(Global.img); -> nullPointerExeption becouse v is not initialize
Added:
BitmapFactory.Options bitmapOptions = new BitmapFactory.Options();
bitmapOptions.inJustDecodeBounds = false;
bitmapOptions.inPreferredConfig = Config.RGB_565;
bitmapOptions.inDither = true;
For "Out of memory" error.

Related

How do I know/get notified that my activity (android) has ended? [duplicate]

In my activity, I'm calling a second activity from the main activity by startActivityForResult. In my second activity, there are some methods that finish this activity (maybe without a result), however, just one of them returns a result.
For example, from the main activity, I call a second one. In this activity, I'm checking some features of a handset, such as does it have a camera. If it doesn't have then I'll close this activity. Also, during the preparation of MediaRecorder or MediaPlayer if a problem happens then I'll close this activity.
If its device has a camera and recording is done completely, then after recording a video if a user clicks on the done button then I'll send the result (address of the recorded video) back to the main activity.
How do I check the result from the main activity?
From your FirstActivity, call the SecondActivity using the startActivityForResult() method.
For example:
int LAUNCH_SECOND_ACTIVITY = 1
Intent i = new Intent(this, SecondActivity.class);
startActivityForResult(i, LAUNCH_SECOND_ACTIVITY);
In your SecondActivity, set the data which you want to return back to FirstActivity. If you don't want to return back, don't set any.
For example: In SecondActivity if you want to send back data:
Intent returnIntent = new Intent();
returnIntent.putExtra("result",result);
setResult(Activity.RESULT_OK,returnIntent);
finish();
If you don't want to return data:
Intent returnIntent = new Intent();
setResult(Activity.RESULT_CANCELED, returnIntent);
finish();
Now in your FirstActivity class, write the following code for the onActivityResult() method.
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == LAUNCH_SECOND_ACTIVITY) {
if(resultCode == Activity.RESULT_OK){
String result=data.getStringExtra("result");
}
if (resultCode == Activity.RESULT_CANCELED) {
// Write your code if there's no result
}
}
} //onActivityResult
To implement passing data between two activities in a much better way in Kotlin, please go through 'A better way to pass data between Activities'.
How to check the result from the main activity?
You need to override Activity.onActivityResult() and then check its parameters:
requestCode identifies which app returned these results. This is defined by you when you call startActivityForResult().
resultCode informs you whether this app succeeded, failed, or something different
data holds any information returned by this app. This may be null.
Example
To see the entire process in context, here is a supplemental answer. See my fuller answer for more explanation.
MainActivity.java
public class MainActivity extends AppCompatActivity {
// Add a different request code for every activity you are starting from here
private static final int SECOND_ACTIVITY_REQUEST_CODE = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
// "Go to Second Activity" button click
public void onButtonClick(View view) {
// Start the SecondActivity
Intent intent = new Intent(this, SecondActivity.class);
startActivityForResult(intent, SECOND_ACTIVITY_REQUEST_CODE);
}
// This method is called when the second activity finishes
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
// check that it is the SecondActivity with an OK result
if (requestCode == SECOND_ACTIVITY_REQUEST_CODE) {
if (resultCode == RESULT_OK) { // Activity.RESULT_OK
// get String data from Intent
String returnString = data.getStringExtra("keyName");
// set text view with string
TextView textView = (TextView) findViewById(R.id.textView);
textView.setText(returnString);
}
}
}
}
SecondActivity.java
public class SecondActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_second);
}
// "Send text back" button click
public void onButtonClick(View view) {
// get the text from the EditText
EditText editText = (EditText) findViewById(R.id.editText);
String stringToPassBack = editText.getText().toString();
// put the String to pass back into an Intent and close this activity
Intent intent = new Intent();
intent.putExtra("keyName", stringToPassBack);
setResult(RESULT_OK, intent);
finish();
}
}
Complementing the answer from Nishant, the best way to return the activity result is:
Intent returnIntent = getIntent();
returnIntent.putExtra("result",result);
setResult(RESULT_OK,returnIntent);
finish();
I was having a problem with
new Intent();
Then I found out that the correct way is using
getIntent();
to get the current intent.
startActivityForResult: Deprecated in Android X
For the new way we have registerForActivityResult.
In Java :
// You need to create a launcher variable inside onAttach or onCreate or global, i.e, before the activity is displayed
ActivityResultLauncher<Intent> launchSomeActivity = registerForActivityResult(
new ActivityResultContracts.StartActivityForResult(),
new ActivityResultCallback<ActivityResult>() {
#Override
public void onActivityResult(ActivityResult result) {
if (result.getResultCode() == Activity.RESULT_OK) {
Intent data = result.getData();
// your operation....
}
}
});
public void openYourActivity() {
Intent intent = new Intent(this, SomeActivity.class);
launchSomeActivity.launch(intent);
}
In Kotlin :
var resultLauncher = registerForActivityResult(StartActivityForResult()) { result ->
if (result.resultCode == Activity.RESULT_OK) {
val data: Intent? = result.data
// your operation...
}
}
fun openYourActivity() {
val intent = Intent(this, SomeActivity::class.java)
resultLauncher.launch(intent)
}
Advantage:
The new way is reduce complexity which we faced when we call the activity from a fragment or from another activity
Easily ask for any permission and get callback
For those who have problem with wrong requestCode in onActivityResult
If you are calling startActivityForResult() from your Fragment, the requestCode is changed by the Activity that owns the Fragment.
If you want to get the correct resultCode in your activity try this:
Change:
startActivityForResult(intent, 1); To:
getActivity().startActivityForResult(intent, 1);
The ActivityResultRegistry is the recommended approach
ComponentActivity now provides an ActivityResultRegistry that lets you handle the startActivityForResult()+onActivityResult() as well as requestPermissions()+onRequestPermissionsResult() flows without overriding methods in your Activity or Fragment, brings increased type safety via ActivityResultContract, and provides hooks for testing these flows.
It is strongly recommended to use the Activity Result APIs introduced in Android 10 Activity 1.2.0-alpha02 and Fragment 1.3.0-alpha02.
Add this to your build.gradle
def activity_version = "1.2.0-beta01"
// Java language implementation
implementation "androidx.activity:activity:$activity_version"
// Kotlin
implementation "androidx.activity:activity-ktx:$activity_version"
How to use the pre-built contract
This new API has the following pre-built functionalities
TakeVideo
PickContact
GetContent
GetContents
OpenDocument
OpenDocuments
OpenDocumentTree
CreateDocument
Dial
TakePicture
RequestPermission
RequestPermissions
An example that uses the takePicture contract:
private val takePicture = prepareCall(ActivityResultContracts.TakePicture()) { bitmap: Bitmap? ->
// Do something with the Bitmap, if present
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
button.setOnClickListener { takePicture() }
}
So what’s going on here? Let’s break it down slightly. takePicture is just a callback which returns a nullable Bitmap - whether or not it’s null depends on whether or not the onActivityResult process was successful. prepareCall then registers this call into a new feature on ComponentActivity called the ActivityResultRegistry - we’ll come back to this later. ActivityResultContracts.TakePicture() is one of the built-in helpers which Google have created for us, and finally invoking takePicture actually triggers the Intent in the same way that you would previously with Activity.startActivityForResult(intent, REQUEST_CODE).
How to write a custom contract
A simple contract that takes an Int as an input and returns a string that the requested Activity returns in the result Intent.
class MyContract : ActivityResultContract<Int, String>() {
companion object {
const val ACTION = "com.myapp.action.MY_ACTION"
const val INPUT_INT = "input_int"
const val OUTPUT_STRING = "output_string"
}
override fun createIntent(input: Int): Intent {
return Intent(ACTION)
.apply { putExtra(INPUT_INT, input) }
}
override fun parseResult(resultCode: Int, intent: Intent?): String? {
return when (resultCode) {
Activity.RESULT_OK -> intent?.getStringExtra(OUTPUT_STRING)
else -> null
}
}
}
class MyActivity : AppCompatActivity() {
private val myActionCall = prepareCall(MyContract()) { result ->
Log.i("MyActivity", "Obtained result: $result")
}
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
...
button.setOnClickListener {
myActionCall(500)
}
}
}
Check this official documentation for more information.
If you want to update the user interface with the activity result, you can't to use this.runOnUiThread(new Runnable() {}. Doing this, the UI won't refresh with the new value. Instead, you can do this:
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_CANCELED) {
return;
}
global_lat = data.getDoubleExtra("LATITUDE", 0);
global_lng = data.getDoubleExtra("LONGITUDE", 0);
new_latlng = true;
}
#Override
protected void onResume() {
super.onResume();
if(new_latlng)
{
PhysicalTagProperties.this.setLocation(global_lat, global_lng);
new_latlng=false;
}
}
This seems silly, but it works pretty well.
In Kotlin
Suppose A & B are activities the navigation is from A -> B
We need the result back from A <- B
in A
// calling the Activity B
resultLauncher.launch(Intent(requireContext(), B::class.java))
// we get data in here from B
private var resultLauncher =
registerForActivityResult(ActivityResultContracts.StartActivityForResult()) { result ->
when (result.resultCode) {
Activity.RESULT_OK -> {
result.data?.getStringExtra("VALUE")?.let {
// data received here
}
}
Activity.RESULT_CANCELED -> {
// cancel or failure
}
}
}
In B
// Sending result value back to A
if (success) {
setResult(RESULT_OK, Intent().putExtra("VALUE", value))
} else {
setResult(RESULT_CANCELED)
}
It is a very common problem on Android
It can be broken down into three pieces
Start Activity B (happens in Activity A)
Set requested data (happens in activity B)
Receive requested data (happens in activity A)
startActivity B
Intent i = new Intent(A.this, B.class);
startActivity(i);
Set requested data
In this part, you decide whether you want to send data back or not when a particular event occurs.
E.g.: In activity B there is an EditText and two buttons b1, b2.
Clicking on Button b1 sends data back to activity A.
Clicking on Button b2 does not send any data.
Sending data
b1......clickListener
{
Intent resultIntent = new Intent();
resultIntent.putExtra("Your_key", "Your_value");
setResult(RES_CODE_A, resultIntent);
finish();
}
Not sending data
b2......clickListener
{
setResult(RES_CODE_B, new Intent());
finish();
}
The user clicks the back button
By default, the result is set with Activity.RESULT_CANCEL response code
Retrieve result
For that override onActivityResult method
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RES_CODE_A) {
// b1 was clicked
String x = data.getStringExtra("RES_CODE_A");
}
else if(resultCode == RES_CODE_B){
// b2 was clicked
}
else{
// The back button was clicked
}
}
I will post the new "way" with Android X in a short answer (because in some case you does not need custom registry or contract). If you want more information, see: Getting a result from an activity
Important: there is actually a bug with the backward compatibility of Android X so you have to add fragment_version in your Gradle file. Otherwise you will get an exception "New result API error : Can only use lower 16 bits for requestCode".
dependencies {
def activity_version = "1.2.0-beta01"
// Java language implementation
implementation "androidx.activity:activity:$activity_version"
// Kotlin
implementation "androidx.activity:activity-ktx:$activity_version"
def fragment_version = "1.3.0-beta02"
// Java language implementation
implementation "androidx.fragment:fragment:$fragment_version"
// Kotlin
implementation "androidx.fragment:fragment-ktx:$fragment_version"
// Testing Fragments in Isolation
debugImplementation "androidx.fragment:fragment-testing:$fragment_version"
}
Now you just have to add this member variable of your activity. This use a predefined registry and generic contract.
public class MyActivity extends AppCompatActivity{
...
/**
* Activity callback API.
*/
// https://developer.android.com/training/basics/intents/result
private ActivityResultLauncher<Intent> mStartForResult = registerForActivityResult(new ActivityResultContracts.StartActivityForResult(),
new ActivityResultCallback<ActivityResult>() {
#Override
public void onActivityResult(ActivityResult result) {
switch (result.getResultCode()) {
case Activity.RESULT_OK:
Intent intent = result.getData();
// Handle the Intent
Toast.makeText(MyActivity.this, "Activity returned ok", Toast.LENGTH_SHORT).show();
break;
case Activity.RESULT_CANCELED:
Toast.makeText(MyActivity.this, "Activity canceled", Toast.LENGTH_SHORT).show();
break;
}
}
});
Before new API you had :
btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MyActivity .this, EditActivity.class);
startActivityForResult(intent, Constants.INTENT_EDIT_REQUEST_CODE);
}
});
You may notice that the request code is now generated (and hold) by the Google framework.
Your code becomes:
btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MyActivity .this, EditActivity.class);
mStartForResult.launch(intent);
}
});
First you use startActivityForResult() with parameters in the first Activity and if you want to send data from the second Activity to first Activity then pass the value using Intent with the setResult() method and get that data inside the onActivityResult() method in the first Activity.
In your Main Activity
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
findViewById(R.id.takeCam).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent=new Intent(getApplicationContext(),TakePhotoActivity.class);
intent.putExtra("Mode","Take");
startActivity(intent);
}
});
findViewById(R.id.selectGal).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent=new Intent(getApplicationContext(),TakePhotoActivity.class);
intent.putExtra("Mode","Gallery");
startActivity(intent);
}
});
}
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
}
In Second Activity to Display
private static final int CAMERA_REQUEST = 1888;
private ImageView imageView;
private static final int MY_CAMERA_PERMISSION_CODE = 100;
private static final int PICK_PHOTO_FOR_AVATAR = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_take_photo);
imageView=findViewById(R.id.imageView);
if(getIntent().getStringExtra("Mode").equals("Gallery"))
{
pickImage();
}
else {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (checkSelfPermission(Manifest.permission.CAMERA) != PackageManager.PERMISSION_GRANTED) {
requestPermissions(new String[]{Manifest.permission.CAMERA}, MY_CAMERA_PERMISSION_CODE);
} else {
Intent cameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(cameraIntent, CAMERA_REQUEST);
}
}
}
}
public void pickImage() {
Intent intent = new Intent(Intent.ACTION_PICK);
intent.setType("image/*");
startActivityForResult(intent, PICK_PHOTO_FOR_AVATAR);
}
#Override
public void onRequestPermissionsResult(int requestCode, #NonNull String[] permissions, #NonNull int[] grantResults)
{
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
if (requestCode == MY_CAMERA_PERMISSION_CODE)
{
if (grantResults[0] == PackageManager.PERMISSION_GRANTED)
{
Intent cameraIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(cameraIntent, CAMERA_REQUEST);
}
else
{
Toast.makeText(this, "Camera Permission Denied..", Toast.LENGTH_LONG).show();
}
}
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == CAMERA_REQUEST && resultCode == Activity.RESULT_OK) {
Bitmap photo = (Bitmap) data.getExtras().get("data");
imageView.setImageBitmap(photo);
}
if (requestCode == PICK_PHOTO_FOR_AVATAR && resultCode == Activity.RESULT_OK) {
if (data == null) {
Log.d("ABC","No Such Image Selected");
return;
}
try {
Uri selectedData=data.getData();
Log.d("ABC","Image Pick-Up");
imageView.setImageURI(selectedData);
InputStream inputStream = getApplicationContext().getContentResolver().openInputStream(selectedData);
Bitmap bitmap = BitmapFactory.decodeStream(inputStream);
Bitmap bmp=MediaStore.Images.Media.getBitmap(getContentResolver(),selectedData);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch(IOException e){
}
}
}
You need to override Activity.onActivityResult():
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_CODE_ONE) {
String a = data.getStringExtra("RESULT_CODE_ONE");
}
else if(resultCode == RESULT_CODE_TWO){
// b was clicked
}
else{
}
}

Activity intent child doesn't return data to parent, toast is not shown

Greetings fellow programmers,
I have been having some issues with understanding why my child's intent doesn't return the proper value to my parent's intent properly.
private static final int REQUEST_CODE_CHEAT = 0;
Now here is how I call my explicit intent
mButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
boolean isTrue = mStatements[mStatementIndex].isAnswerTrue();
Intent intent = SubActivity.newIntent(MainActivity.this, isTrue);
startActivityForResult(intent, REQUEST_CODE_CHEAT);
}
});
This is the code for the SubActivity that creates the interfacing Intent
public static Intent newIntent(Context packageContext, boolean answerIsTrue){
Intent intent = new Intent(packageContext, SubActivity.class);
intent.putExtra(EXTRA_ANSWER_SHOWN, answerIsTrue);
return intent;
}
Also, have the following keys to keep track of what goes where
private static final String EXTRA_ANSWER_IS_TRUE = "com.tsourtzis.android.test.answer_is_true";
private static final String EXTRA_ANSWER_SHOWN = "com.tsourtzis.android.test.answer_shown";
Finally some methods to be certain what values are passed
private void setAnswerShownResult(boolean isAnswerShown){
Intent data = new Intent();
data.putExtra(EXTRA_ANSWER_IS_TRUE, isAnswerShown);
setResult(RESULT_OK, data);
}
Here I'm sending back the intent to the MainActivity with setResult();
public static boolean wasAnswerShown(Intent result){
return result.getBooleanExtra(EXTRA_ANSWER_SHOWN, false);
}
Moreover, I have this method here to evaluate the result, but checking first if the user has created it.
public void evaluateStatement(boolean userChoice){
boolean statementValue = mStatements[mStatementIndex].isAnswerTrue();
int textResId = 0;
if(mBoolResult){
textResId = R.string.judgment_toast;
}else{
if(userChoice == statementValue){
textResId = R.string.correct_toast;
}else{
textResId = R.string.incorrect_toast;
}
}
Toast.makeText(this, textResId, Toast.LENGTH_SHORT).show();
}
Notice, I have stated the following my MainActivity after using setResult(...) and a field value for keeping the boolean result from the Sub activity.
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data){
if(resultCode != Activity.RESULT_OK){
return;
}
if(requestCode == REQUEST_CODE_CHEAT){
if(data == null){
return;
}
mBoolResult = SubActivity.wasAnswerShown(data);
}
}
Finally just to be clear, here is the field that I have in MainActivity.
private boolean mBoolResult;
I'm not looking for any code answer, I just want to understand why it doesn't work. Thank you!
Do you finish() your SubActivity ?
Seeing that the Toast should be shown any time the method evaluateStatement is called, I guess onActivityResult doesn't dispatch the call to it.
Can you explicit where is the onActivityResult you show last? It's unclear since it's calling CheatActivity#wasAnswerShown() as if it is not in CheatActivity (MainActivity?)

Wait the result of an activity

I have a class(A) who need to take a picture, so I create an other class(B) with this responsibility. But the problem is, that A don't wait the result of B. How can I do that?
Here is my code :
Class which take the picture
static final int REQUEST_IMAGE_CAPTURE = 1;
Bitmap image = null;
public void takePicture(Context context, Activity activity) {
Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
if (takePictureIntent.resolveActivity(context.getPackageManager()) != null) {
activity.startActivityForResult(takePictureIntent, REQUEST_IMAGE_CAPTURE);
}
try {
wait();
} catch (InterruptedException e) {
e.printStackTrace();
}
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_IMAGE_CAPTURE && resultCode == RESULT_OK) {
Bundle extras = data.getExtras();
image = (Bitmap) extras.get("data");
}
}
public Bitmap getImage(){
return image;
}
The method which call the the Camera class
public void openCamera() {
Bitmap image = null;
camera.takePicture((Context) _addView, (Activity) _addView);
image = camera.getImage();
ByteArrayOutputStream outStream = new ByteArrayOutputStream();
image.compress(Bitmap.CompressFormat.JPEG, 100, outStream);
byte[] picture = outStream.toByteArray();
_addView.SetCameraPicture(picture);
}
While taking pictures what you are doing is opening another app(startActivityForResult) which is capable of taking pictures. When the app finishes taking the picture you are sent the data through an intent which you listen using onActivityResult. The other class B must be an
Activity(startActivityForResult() can be called only from an Activity).
So with your scenario, you must first open Activity B, then take the picture,
put the result into an intent and start Activity A with that data, which just does not make any sense. If you want to follow DRY principles put your photo taking method into a utility class and dependency inject your class to wherever you need it. Hope this helps.
You can always try to make class B async and then let class A await the method of class B

Returning Image Resource ID

I'm trying to get a program to let the user to import a custom background.
Here's where I'm at:
I have the getDrawable function taking another function as an argument:
mDrawableBg = getResources().getDrawable(getImage());
getImage() is suppose to return a integer referencing the selected image, here is the code (so far) for that function:
public int getImage(){
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("image/*");
startActivityForResult(intent, 10);
}
This is suppose to open the gallery and let the user select an image. I would then use mDrawableBg to set the background. I'm not sure how to return a reference ID to that selected image though. Any suggestions?
Try this:
String pathName = "selected Image path";
Resources res = getResources();
Bitmap bitmap = BitmapFactory.decodeFile(pathName);
BitmapDrawable bd = new BitmapDrawable(res, bitmap);
View view = findViewById(R.id.container);
view.setBackgroundDrawable(bd);
The way you're attempting to do it is not possible, I'm afraid. One of the things you'll want to learn as a new Android developer is how the cycle between activities works. In your case, you're running an Activity that calls upon an Intent to get data from it. However, in the Android API, an Intent can only be referenced on its own time. This means you can't use your getImage() method the way you had tried.
There is hope, though!
What you first need to do is call the Intent. You will do this through the code you have now in getImage():
public void getImage() { // This has to be a void!
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("image/*");
startActivityForResult(intent, 10);
}
This method will now start the Image Picker that you want users to select from. Next, you have to catch what is returned. This cannot be returned from your getImage() method, but instead must be collected from elsewhere.
You must implement the below method:
#Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
if (resultCode == RESULT_OK) {
final int SELECT_PICTURE = 1; // Hardcoded from API
if (requestCode == SELECT_PICTURE) {
String pathToImage = data.getData().getPath(); // Get path to image, returned by the image picker Intent
mDrawableBg = Drawable.createFromPath(pathToImage); // Get a Drawable from the path
}
}
}
Lastly, instead of calling mDrawableBg = getResources().getDrawable(getImage());, just call getImage();. This will initialize the Image Picker.
Some reading:
Android Activity (notably stuff about Intents and getting a result back)
Android Drawable
Getting a Drawable from a path
More on the Image Picker Intent
Good luck!
I'm not sure, but if you mean you don't know how to receive results from that intent, you can use :
#Override
protected void onActivityResult(int requestCode,int resultCode,Intent data)
{
super.onActivityResult(requestCode, resultCode, data);
if(resultCode == RESULT_OK)
{
if (requestCode == 10)
{
// DoSomething
}
}
}

how can i send image via activities in android

I have an application that allow users to choose picture from native gallery then I show this image in image view widget.
My question is:
1-i have to send this image to another Activity. How can i do it.
2-in the receiver Activity i should show it in image view widget as in image not link or Something
I tried this code but it gives me a RunTime Error
Bitmap image = Bitmap.createBitmap(view.getWidth(), view.getHeight(),Bitmap.Config.RGB_565);
 view.draw(new Canvas(image));
 String url = Images.Media.insertImage(getContentResolver(), image,"title", null);
Just follow the below steps...
Uri uri = null;
1) on any click event use the below code to open native gallery
Intent intent = new Intent();
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent, "Select Picture"),0);
This will open gallery select picture will return you to your activity. OnActivity result.
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
switch (requestCode) {
case 0:
if (resultCode == RESULT_OK) {
try {
uri = Uri.parse(data.getDataString());
imageView.setImageUri(uri);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}}
break;
}
}
2) Also instead of passing the image you can pass the URI to next activity as you pass string and inthe secont activity you get it using intent.
Intent i = new Intent(this, Second.class);
i.putExtra("URI", uri.toString() );
startActivity(i);
and in the second activity
String uri = getIntent().getStringExtra("URI");
Now you have string just set it to the image view like below
imageView.setImageUri(Uri.parse(uri));
Use intent putExtra and send uri of the image user selected in Acvtivity1 and in second activity use intent getExtra to read the uri
Refer this answer https://stackoverflow.com/a/7325248/308251
Maybe this is not what you're looking for and it's a bit poor but saved my life when I needed to pass objects between Activities.
public class MagatzemImg {
private static MagatzemImg instance = null;
private static Bitmap img;
public MagatzemImg(){
img=null;
}
public static MagatzemImg getInstance() {
if (instance == null)
instance = new MagatzemImg();
return instance;
}
public static void setImg(Bitmap im){
img = im;
}
public static Bitmap getImg(){
Bitmap imgAux = img;
img = null;
return imgAux;
}
}
And then from the new activity:
MagatzemImg.getInstance();
image = MagatzemImg.getImg();
You can 'assure' to the new Activity that the image exists inside the Static Class through putExtra("image",true) or something else you prefer, like checking if the "image" is null.

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