Develop Reference

Dialog pops up very slow

In my app I have implemented this custom dialog (which has a fairly complex layout) by extending DialogFragment. I expect this dialog to pop up when I click a button in my layout. (Which I have successfully achieved). But the problem is that the dialog shows up in a janky manner.
My custom dialog class:
public class CustomizeDialog extends DialogFragment implements AdapterView.OnItemSelectedListener {
// field declarations go here
#NonNull
#Override
public Dialog onCreateDialog(#Nullable Bundle savedInstanceState) {
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
LayoutInflater inflater = getActivity().getLayoutInflater();
View view = inflater.inflate(R.layout.customize_dialog, null);
builder.setView(view)
.setTitle("Customize")
.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
}
})
.setPositiveButton("Let's go!", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
Intent intent = new Intent();
intent.setAction("fromDialog");
intent.putExtra("ratio",getRatio(paperSizeSpinner.getSelectedItem().toString()));
if(isOrientationSpinnerVisible){
intent.putExtra("isCustom",false);
intent.putExtra("orientation",orientationSpinner.getSelectedItem().toString());
} else {
intent.putExtra("isCustom",true);
}
intentProvider.getIntent(intent);
}
});
widthEditText = view.findViewById(R.id.width_et);
heightEditText = view.findViewById(R.id.height_et);
widthEditText.setEnabled(false);
heightEditText.setEnabled(false);
paperSizeSpinner = view.findViewById(R.id.paper_size_spinner);
orientationSpinner = view.findViewById(R.id.orientation_spinner);
// ArrayList for populating paperSize spinner via paperSizeAdapter
ArrayList<String> paperSizes = new ArrayList<>();
paperSizes.add("A0");
paperSizes.add("A1");
paperSizes.add("A2");
paperSizes.add("A3");
paperSizes.add("A4");
paperSizes.add("A5");
paperSizes.add("Custom");
// ArrayList for populating orientation spinner via orientationAdapter
ArrayList<String> orientation = new ArrayList<>();
orientation.add("Portrait");
orientation.add("Landscape");
// arrayAdapters containing arraylists to populate spinners
ArrayAdapter paperSizeAdapter = new ArrayAdapter(getActivity(), android.R.layout.simple_spinner_dropdown_item, paperSizes);
ArrayAdapter orientationAdapter = new ArrayAdapter(getActivity(), android.R.layout.simple_spinner_dropdown_item, orientation);
paperSizeSpinner.setAdapter(paperSizeAdapter);
orientationSpinner.setAdapter(orientationAdapter);
paperSizeSpinner.setSelection(4);
paperSizeSpinner.setOnItemSelectedListener(this);
orientationSpinner.setOnItemSelectedListener(this);
return builder.create();
}
// These are some important complex ui functionalities
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
if (parent.getId() == R.id.paper_size_spinner) {
if (position == 6) {
widthEditText.setEnabled(true);
heightEditText.setEnabled(true);
orientationSpinner.setEnabled(false);
isOrientationSpinnerVisible = false;
} else {
widthEditText.setEnabled(false);
heightEditText.setEnabled(false);
orientationSpinner.setEnabled(true);
isOrientationSpinnerVisible = true;
}
}
}
#Override
public void onNothingSelected(AdapterView<?> parent) {
}
// interface used to communicate with the parent activity
public interface IntentProvider {
// this method is used to provide the intent to the parent activity
void getIntent(Intent intent);
}
// instantiating the interface object and throwing error if parent activity does not implement this interface
#Override
public void onAttach(#NonNull Context context) {
super.onAttach(context);
try {
intentProvider = (IntentProvider) context;
} catch (ClassCastException e) {
throw new ClassCastException(context.toString() + " must implement IntentProvider");
}
}
}
MainActivity class:
public class MainActivity extends AppCompatActivity implements CustomizeDialog.IntentProvider {
// field declarations go here
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
imageView = findViewById(R.id.image);
// instantiating the dialog
final CustomizeDialog dialog = new CustomizeDialog();
findViewById(R.id.button).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// showing the dialog on click
dialog.show(getSupportFragmentManager(),"");
}
});
}
// via this method I receive the intent from the dialog
// I know intent might not be the best option for this function but let's let it be here for now
#Override
public void getIntent(Intent intent) {
ratio = intent.getFloatExtra("ratio",3);
isCustom = intent.getBooleanExtra("isCustom",false);
orientation = intent.getStringExtra("orientation");
launchChooser();
}
}
Let me know in the comments if you want the layout code for the dialog.
What I tried:
Implementing threading so that my dialog is ready in a background thread and show it onButtonClick. But this is not allowed in general as any other thread except UI thread aren't supposed to touch UI related events.
Using onCreateView instead of onCreateDialog to inflate the layout directly.
Making the dialog a global variable, initialized it in onCreate and then show the dialog onButtonClick.
Switched to CONSTRAINT LAYOUT
Using an activity as a dialog by setting the dialog theme to the activity in the manifest file.
Launched my app in a device with better hardware than mine.
BUT NOTHING WORKED
What I want:
Why is my dialog janky? and what I need to do to make the dialog pop up faster?
In case anybody wants here's the link to my app repo on github.

AlertDialog and DialogFragment frameworks are slow because they need to some time to do calculations and fragment stuffs. So a solution to this problem is, using the Dialog framework straight away.
Use the Dialog framework's constructor to initialize a Dialog object like this:
Dialog dialog = new Dialog(context, R.style.Theme_AppCompat_Dialog);
// the second parameter is not compulsory and you can use other themes as well
Define the layout and then use dialog.setContentView(R.layout.name_of_layout).
Use dialog.findViewById(R.id.name_of_view) to reference views from the dialog's layout file
And then implement the logic just like anyone would do in an activity class. Find out the best implementation for your use case by reading the official documentation.

Calling a method in a Fragment from an AlertDialog

Could you please help with the below:
I am trying to call the method deletePlayer inside the fragment PlayersActivityFragment from the alertdialog NameAlertDialogFragment.
The code is below:
public static class PlayersActivityFragment extends Fragment {
ArrayList<Player> arrayPlayers;
ListView listViewPlayers;
//PlayerAdapter adapter;
public PlayersActivityFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
arrayPlayers = new ArrayList<Player>();
View rootView = inflater.inflate(R.layout.fragment_activity_players, container, false);
Button buttonAddPlayer = (Button) rootView.findViewById(R.id.button_addplayers);
buttonAddPlayer.setOnClickListener(new View.OnClickListener(){
public void onClick(View view) {
arrayPlayers.add(new Player("Player", 0));
Player selectedPlayer = arrayPlayers.get(arrayPlayers.size()-1);
((PlayersActivity)getActivity()).showNameDialogFragment(selectedPlayer);
}
});
listViewPlayers = (ListView) rootView.findViewById(R.id.listView_playername);
return rootView;
}
public void deletePlayer(){
arrayPlayers.remove(arrayPlayers.size()-1);
}
}
void showNameDialogFragment(Player player) {
mDialog = NameAlertDialogFragment.newInstance(player);
mDialog.show(getFragmentManager(),"SCORE DIALOG");
}
// Class that creates the AlertDialog
public static class NameAlertDialogFragment extends DialogFragment {
static Player selectedPlayer;
public static NameAlertDialogFragment newInstance(Player player) {
selectedPlayer = player;
return new NameAlertDialogFragment();
}
// Build AlertDialog using AlertDialog.Builder
#Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
// Get the layout inflater
LayoutInflater inflater = getActivity().getLayoutInflater();
final View view = inflater.inflate(R.layout.alertdialog_name, null);
final EditText editTextName = (EditText) view.findViewById(R.id.edittext_name);
return new AlertDialog.Builder(getActivity())
// Inflate and set the layout for the dialog
// Pass null as the parent view because its going in the dialog layout
.setView(view)
.setMessage("Enter Player's Name:")
//Set up Yes Button
.setPositiveButton("Done", new DialogInterface.OnClickListener() {
public void onClick(final DialogInterface dialog, int id) {
mName = editTextName.getText().toString().trim();
selectedPlayer.setName(mName);
}
})
.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
//PlayersActivityFragment playersActivityFragment = (PlayersActivityFragment) getFragmentManager().findFragmentById(R.id.container);
//playersActivityFragment.deletePlayer();
//((PlayersActivityFragment)getTargetFragment()).deletePlayer();
NameAlertDialogFragment.this.getDialog().cancel();
}
})
.create();
}
}
The two different ways I have tried to call the methods are commented out in the .setNegativeButton onClickListener:
PlayersActivityFragment playersActivityFragment = (PlayersActivityFragment) getFragmentManager().findFragmentById(R.id.container);
playersActivityFragment.deletePlayer();
and
((PlayersActivityFragment)getTargetFragment()).deletePlayer();
Thank you!

First of all, why are all of your classes static? Anyway, here's an answer that should work...
Try using an interface as a callback. For example:
First create an interface.
public interface NameAlertDialogListener {
public void onNegativeClick();
}
Then have PlayersFragment implement NameAlertDialogListener.
public static class PlayersActivityFragment extends Fragment implements NameAlertDialogListener
Next, in the PlayersFragment, create a method called onNegativeClick.
#Override
public void onNegativeClick() {
//delete or whatever you want to do.
}
Create a member variable for the listener:
static Player selectedPlayer;
static NameAlertDialogListener mCallBack;
Next create a method in the dialog fragment called setListener.
public void setListener(NameAlertDialogListener callback) {
try {
mCallBack = callback;
} catch (ClassCastException e){
throw new ClassCastException(callback.toString() + " must implement NameAlertDialogListener" );
}
}
Then, when you create the dialog fragment call the setListener method.
void showNameDialogFragment(Player player) {
mDialog = NameAlertDialogFragment.newInstance(player);
mDialog.setListener(this);
mDialog.show(getFragmentManager(),"SCORE DIALOG");
}
Lastly, in your negative click listener:
.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
mCallBack.onNegativeClick() ;
NameAlertDialogFragment.this.getDialog().cancel();
}
})

I am not sure if this is the correct way of doing things, but I have come to a working solution.
First I moved ArrayList<Player> arrayPlayers; outside of the PlayersActivityFragment fragment.
Then I moved the method:
public void deletePlayer(){
arrayPlayers.remove(arrayPlayers.size()-1);
}
outside of the PlayersActivityFragment fragment.
I then called the deletePlayer() method inside the alertdialog with the line ((PlayersActivity)getActivity()).deletePlayer();.

Actually, I have a little hack, it's not really good, but it's easy to implement: declare PlayersActivityFragment variable in your DialogFragment. Then change your constructor to:
public static NameAlertDialogFragment newInstance(Player player,PlayersActivityFragment fragment ){
selectedPlayer = player;
NameAlertDialogFragment test = new NameAlertDialogFragment();
test.playerActivityFragment = fragment;
return test;
}
Then you can call playerActivityFragment.deletePlayer() everywhere in your DialogFragment.
P/s: The best way is implement interface, but for lazy coder like me, the method above is better lol!

onCreateDialog is called after show?

I am trying to implement custom DialogFragment. But when I try to show it I am getting NullPointerException. Also as I have noticed onCreateDialog is never implictly called.
What is wrong with it. I have read official manual, and followed all steps in it DialogFragment
Here is my code for custom Dialog Fragment
public class UserInputDialogFragment extends DialogFragment {
InputDialogListener mListener;
private EditText mTextEdit;
public UserInputDialogFragment() {
super();
}
// Use this instance of the interface to deliver action events
#Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
// Get the layout inflater
LayoutInflater inflater = getActivity().getLayoutInflater();
// Inflate and set the layout for the dialog
// Pass null as the parent view because its going in the dialog layout
View mainView = inflater.inflate(R.layout.dialog_input, null);
builder.setView(mainView);
mTextEdit = (EditText) mainView.findViewById(R.id.user_input);
if (mTextEdit==null) {
Log.e("ERROR","Text edit is null");
}
// Add action buttons
builder.setPositiveButton(R.string.ok_btn, new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int id) {
mListener.onDialogPositiveClick(UserInputDialogFragment.this,mTextEdit.getText().toString());
}
});
builder.setNegativeButton(R.string.cancel_bnt, new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
mListener.onDialogNegativeClick(UserInputDialogFragment.this,mTextEdit.getText().toString());
UserInputDialogFragment.this.getDialog().cancel();
}
});
return builder.create();
}
public interface InputDialogListener {
public void onDialogPositiveClick(DialogFragment dialog, String userInput);
public void onDialogNegativeClick(DialogFragment dialog, String userInput);
}
public void showAndAddHint(FragmentManager manager,String tag,String hint) {
this.onCreateDialog(null);
mTextEdit.setHint(hint);
this.show(manager,tag);
}
#Override
public void onAttach(Activity activity) {
super.onAttach(activity);
// Verify that the host activity implements the callback interface
try {
// Instantiate the NoticeDialogListener so we can send events to the host
mListener = (InputDialogListener) activity;
} catch (ClassCastException e) {
// The activity doesn't implement the interface, throw exception
throw new ClassCastException(activity.toString()
+ " must implement InputDialogListener");
}
}
}
And I am trying to show dialog this way.
UserInputDialogFragment userInputDialogFragment = new UserInputDialogFragment();
userInputDialogFragment.showAndAddHint(getFragmentManager(),"Please enter phone number",task.phoneNumber);
And here is NullPointerException mTextEdit is null.
public void showAndAddHint(FragmentManager manager,String tag,String hint) {
this.onCreateDialog(null);
mTextEdit.setHint(hint);
this.show(manager,tag);
}

The showAndAddHint method won't work as written. What you should do instead is:
1 - Set a member variable mHint = hint;
2 - Call show() exactly the way you're doing it now.
3 - Read the member variable mHint in on create dialog and use it to set the edit text hint.
Don't call onCreateDialog explicitly because the show method does that for you when needed.

Exception when showing a dialog after orientation change

I have an activity and a fragment inside it.inside fragment, there is a button, and on click of button a dialog shows.
Everything works, until user do a orientation change and click button after it.
IllegalStateException(cannot perform this action after onsaveinstancestate) occurs when user clicks button after orientation change. I'm using android support framework.
Anybody have any idea regarfing this?
Activity Code
public void openMoreDialog(String shareData, String link) {
DialogFragment dialog = new MoreDialog(shareData, link);
dialog.show(getSupportFragmentManager(), "MoreDialog");
}
Fragment Code
public void onAttach(Activity activity) {
super.onAttach(activity);
mControl = (ActivityControl)activity;
}
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
ImageButton moreButton = (ImageButton)v.findViewById(R.id.moreButton);
moreButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
mControl.openMoreDialog(shareData, link);
}
});
return rootView;
}
FragmentDialog code
public class MoreDialog extends DialogFragment {
private String mShareData;
private String mLink;
public MoreDialog(String shareData, String link){
mShareData = shareData;
mLink = link;
}
#Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
// Get the layout inflater
LayoutInflater inflater = getActivity().getLayoutInflater();
View dialogView = inflater.inflate(R.layout.more_dialog, null);
Button openBtn = (Button)dialogView.findViewById(R.id.openBtn);
openBtn.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
openLink(mLink);
}
});
Button shareBtn = (Button)dialogView.findViewById(R.id.shareBtn);
shareBtn.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
shareNews(mShareData);
}
});
builder.setView(dialogView);
return builder.create();
}
private void openLink(String link){
}
private void shareNews(String data){
}
}

Helpful link & solution how to:
https://stackoverflow.com/a/17413324/619673 and btw, constructor in fragment must be empty! Documentation:
http://developer.android.com/reference/android/app/Fragment.html
public Fragment ()
Added in API level 11
Default constructor.
Every fragment must have an empty constructor, so
it can be instantiated when restoring its activity's state. It is
strongly recommended that subclasses do not have other constructors
with parameters, since these constructors will not be called when the
fragment is re-instantiated; instead, arguments can be supplied by the
caller with setArguments(Bundle) and later retrieved by the Fragment
with getArguments().
Applications should generally not implement a constructor. The first
place application code an run where the fragment is ready to be used
is in onAttach(Activity), the point where the fragment is actually
associated with its activity. Some applications may also want to
implement onInflate(Activity, AttributeSet, Bundle) to retrieve
attributes from a layout resource, though should take care here
because this happens for the fragment is attached to its activity.

android starting Activity from Intent in onClickListener in common class returns error

I have a navigation button that I use in each class and want to set its onClickListener in the class that contains all the common code. However I get a
"The method startActivity(Intent) is undefined for the type new View.OnClickListener(){}"
error in startActivity(i).
The relevant code is:
public static void initiateNavigationButton(Context context, View view, int layoutResource) {
final Context classContext = context;
LayoutInflater inflater = LayoutInflater.from(classContext);
View layout = inflater.inflate(layoutResource, (ViewGroup) view);
Button navigationButton = (Button) layout.findViewById(R.id.navigation_button);
navigationButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent i = new Intent(classContext, HomeActivity.class);
startActivity(i);
}
});
}

You are inside an inner class that implements the View.OnClickListener.
That class does not have a startActivity method that you could call, so you need to wrap it in order to access the parent activity's method. Assuming that your class' name is 'MyActivity', change the line startActivity(i); to
MyActivity.this.startActivity(i);