I want to change my menu visibility in layout based on the condition

Question

This is my menu occasion layout...I need to display this delete icon in some condition....

<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    tools:context="ringee.app.com.ringeeapp.Occasion">

    <item
        android:id="@+id/action_settings"
        android:title="@string/action_settings"
        android:orderInCategory="100"
        app:showAsAction="never" />

    <item
        android:id="@+id/menu_cancel_event"
        android:icon="@drawable/delete_icon"
        android:title="Cancel event"
        app:showAsAction="ifRoom"/>
</menu>

Is it possible to change the visibilty of this delete_icon here...Please help me to find out the code

This is my occasion activity code....here delete icon displayed while Adding event as well as Updating event..Here i need to visible delete icon only when the event is updated...I don't need to display that while Adding event....

  public boolean onCreateOptionsMenu(Menu menu) {
            // Inflate the menu; this adds items to the action bar if it is present.    
             this.menu=menu;
            getMenuInflater().inflate(R.menu.menu_occasion, menu);
           hide();
           show();
            return true;
        }
public boolean show()
{
    menu.findItem(R.id.menu_cancel_event).setVisible(true);
        return true;
    }
public boolean hide(){
        menu.findItem(R.id.menu_cancel_event).setVisible(false);
        return false;
    }

        // delete the selected event from event list added here
        @Override
        public boolean onOptionsItemSelected(MenuItem item) {

            switch (item.getItemId()) {
                case R.id.menu_cancel_event:
                    //Setting the value for deleted event
                    eventMO.setIsDelete(1);
                    del();
                    //Triggering the Create event
                    doOnCLickAndOnOptionSelected();
                    return true;
            }

            return super.onOptionsItemSelected(item);
        }

        private void del() {
            //Deleting the event from SQLLite
            SQLiteDatabase db = dbHelper.getWritableDatabase();
            final long Id = eventMO.getEventId();
            db.delete("event", "Event_ID" + " = ?", new String[]{String.valueOf(Id)});
            db.close();
        }

        // Common for delete event and save event(Create button click listener)
        private void doOnCLickAndOnOptionSelected() {
            //We need create button click listener for both delete as well as save the event.so we have this common method.we call this method from delete event and save event
            prgDialog = new ProgressDialog(OccasionActivity.this);
            // Set Progress Dialog Text
            prgDialog.setMessage("Please wait...");
            // Set Cancelable as False
            prgDialog.setCancelable(false);

            prgDialog.show();
            UserMO userMO = dbHelper.getRingeeUserData(1);
            eventMO.setText(custom_Text.getText().toString());
            eventMO.setPlace(event_Place.getText().toString());
            eventMO.setEndTime(end_Time);
            eventMO.setStartTime(start_Time);

            try {
                //date and time format changed here
                String eventDate = btn_Date.getText().toString();
                DateFormat date = new SimpleDateFormat("dd-M-yyyy");
                Date date1 = date.parse(eventDate);
                DateFormat convertDate = new SimpleDateFormat(" yyyy-MM-dd hh:mm:ss");
                eventDate = convertDate.format(date1);
                eventMO.setEventDate(eventDate);

            } catch (ParseException e) {

                e.printStackTrace();
            }
            //eventMO.setEventDate(btn_Date.getText().toString());

            eventMO.setRingeeUserId(userMO.getRingeeUserId());
            //event update functionality added here


            final Long hidden_Text2 = eventId2;
            if ((eventMO.getText() != null) && (eventMO.getPlace() != null) && (eventMO.getEventDate() != null)) {
                if (hidden_Text2 != null) {
                    eventMO.setEventId(hidden_Text2);
                    new AsyncTask<Void, Void, String>() {
                        @Override
                        protected String doInBackground(Void... arg0) {
                            return eventDelegates.updateEvent(eventMO, context);
                        }

                        @Override
                        protected void onPostExecute(String arg0) {
                            prgDialog.dismiss();
                            Intent contactAct = new Intent(getApplicationContext(), UserDashBoardActivity.class);
                            // Clears History of Activity
                            contactAct.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                            startActivity(contactAct);

                        }

                    }.execute(null, null, null);
                    Toast.makeText(getApplicationContext(), "Details updated successfully", Toast.LENGTH_LONG).show();

                } else {

                    new AsyncTask<Void, Void, String>() {
                        @Override
                        protected String doInBackground(Void... arg0) {
                            return eventDelegates.addEvent(eventMO, context);
                        }

                        @Override
                        protected void onPostExecute(String eventId) {
                            prgDialog.dismiss();
                            SharedPreferences.Editor editor = sharedpreferences.edit();
                            editor.putString("eventId", eventId);
                            editor.commit();
                            Intent contactAct = new Intent(getApplicationContext(), ContactActivity.class);
                            // Clears History of Activity
                            contactAct.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                            startActivity(contactAct);
                        }
                    }.execute(null, null, null);
                    Toast.makeText(getApplicationContext(), "Details added successfully", Toast.LENGTH_LONG).show();

                }
            } else {
                prgDialog.dismiss();
                Toast.makeText(context, "Please check Event custom text or Event place or Event date field", Toast.LENGTH_LONG).show();
            }
        }

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_occasion);

            context = getApplicationContext();

            seekBar_startTime = (SeekBar) findViewById(R.id.seekBar1);
            seekBar_startTime.setProgress(0);
            seekBar_startTime.setMax(1440); //minutes in 24 hours(24*60)
            seekBar_startTime.setProgress(1);
            textView_startTime = (TextView) findViewById(R.id.textView1);

            seekBar_endTime = (SeekBar) findViewById(R.id.seekBar2);
            seekBar_endTime.setProgress(0);
            seekBar_endTime.setMax(1440); //minutes in 24 hours(24*60)
            seekBar_endTime.setProgress(1);
            textView_endTime = (TextView) findViewById(R.id.textView2);

            btn_Date = (Button) findViewById(R.id.event_date_button);
            event_Place = (TextView) findViewById(R.id.Enter_Place);
            custom_Text = (TextView) findViewById(R.id.Custom_Text);
            checkBox_onEventDay=(CheckBox) findViewById(R.id.cb_onEventDay);
            checkBox_2DaysBefore=(CheckBox) findViewById(R.id.cb_2DaysBefore);
            checkBox_aWeekBefore=(CheckBox) findViewById(R.id.cb_aWeekBefore);

            btn_create_button = (Button) findViewById(R.id.create_button);
            sharedpreferences = context.getSharedPreferences(Constants.SHARED_PREFERENCE_NAME, Context.MODE_PRIVATE);
            dbHelper = new DatabaseHelper(context);



            btn_Date.setOnClickListener(new View.OnClickListener() {

                @Override
                public void onClick(View v) {

                    DatePickerFragment newFragment = new DatePickerFragment();
                    newFragment.show(getFragmentManager(), "Occasion Date");

                }
            });

            seekBar_startTime.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {


                @Override
                public void onStopTrackingTouch(SeekBar seekBar) {
                }

                @Override
                public void onStartTrackingTouch(SeekBar seekBar) {
                }

                @Override
                public void onProgressChanged(SeekBar seekBar, int progressValue, boolean fromUser) {
                    int minutes;
                    int hours;
                    minutes =progressValue % 60;
                    hours = progressValue/60;
                    int Hours=hours;
                    String am_pm;
                    if (hours==24)
                    {
                        hours = hours-12;
                        am_pm="AM";
                    }
                    else if
                            (hours> 12)
                    {
                        hours= hours- 12;
                        am_pm = "PM";
                    }
                    else if (hours ==0) {

                        hours =hours+12;
                        am_pm = "AM";
                    }
                    else if (hours <12) {
                        am_pm = "AM";
                    }
                    else
                    {
                        am_pm="PM";
                    }

                    if(minutes < 10)
                    {
                        //It shows 12 hours format with AM/PM to user
                        start_Time = String.valueOf(" "+hours+":0"+minutes+am_pm);
                        textView_startTime.setText("Event Start Time :" + start_Time);
                        //It pass 24hours format to database
                        start_Time = String.valueOf(Hours+":0"+minutes);
                    }

                    else {
                        //It shows 12 hours format with AM/PM to user
                        start_Time = String.valueOf(" "+hours+":"+minutes+am_pm);
                        textView_startTime.setText("Event Start Time :" + start_Time);
                        //It pass 24hours format to database
                        start_Time = String.valueOf(Hours+":"+minutes);
                    }


                }

            });


            seekBar_endTime.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
                @Override
                public void onStopTrackingTouch(SeekBar seekBar) {
                }

                @Override
                public void onStartTrackingTouch(SeekBar seekBar) {
                }

                @Override
                public void onProgressChanged(SeekBar seekBar, int progressValue,boolean fromUser) {
                    int minutes;
                    int hours;
                    minutes = progressValue % 60;
                    hours = progressValue/60;
                    int Hours=hours;
                    String am_pm;
                    if (hours==24)
                    {
                        hours = hours-12;
                        am_pm="AM";
                    }
                    else if(hours> 12)
                    {
                        hours= hours- 12;
                        am_pm = "PM";
                    }
                    else if (hours ==0) {

                        hours =hours+12;
                        am_pm = "AM";
                    }
                    else if (hours <12) {
                        am_pm = "AM";
                    }
                    else
                    {
                        am_pm="PM";
                    }
                    if(minutes < 10)
                    {
                        //It shows 12 hours format with AM/PM to user
                        end_Time = String.valueOf(""+hours+":0"+minutes+am_pm);
                        textView_endTime.setText("Event Start Time :" + end_Time);
                        //It pass 24hours format to database
                        end_Time = String.valueOf(Hours+":0"+minutes);
                    }

                    else {
                        //It shows 12 hours format with AM/PM to user
                        end_Time = String.valueOf(""+hours+":"+minutes+am_pm);
                        textView_endTime.setText("Event Start Time :" + end_Time);
                        //It pass 24hours format to database
                        end_Time = String.valueOf(Hours+":"+minutes);
                    }
                }
            });

            //eventid get from OccasionFragment here
            Bundle bundle = this.getIntent().getExtras();
            if (bundle != null) {

                Long eventId1 = bundle.getLong("EventID");
                eventId2 = eventId1;
                String eventName = bundle.getString("EventName");
                custom_Text.setText(eventName);
                String eventPlace = bundle.getString("EventPlace");
                event_Place.setText(eventPlace);
                String eventDate = bundle.getString("EventDate");
                try {
                    //String eventDate = bundle.getString("EventDate");
                    //time string removed from date here
                    String result = eventDate.split(" ")[0];
                    DateFormat sourceDate = new SimpleDateFormat("yyyy-MM-dd");
                    // parse the date string into Date object
                    Date date = sourceDate.parse(result);
                    DateFormat convertDate = new SimpleDateFormat("dd-M-yyyy");
                    // format the date into another format
                    result = convertDate.format(date);
                    btn_Date.setText(result);


                } catch (ParseException e) {

                    e.printStackTrace();
                }
                //Event Start Time and Event End Time string added before the time here
                String eventStart = bundle.getString("EventStart");
                textView_startTime.setText("Event Start Time :" + eventStart);
                String eventEnd = bundle.getString("EventEnd");
                textView_endTime.setText("Event End Time :" + eventEnd);

            }
            checkBox_onEventDay.setOnClickListener(new View.OnClickListener(){

                public void onClick(View v) {
                    if (((CheckBox) v).isChecked()) {
                        Toast.makeText(OccasionActivity.this,
                                "Checked", Toast.LENGTH_LONG).show();
                    }}
            });
            checkBox_2DaysBefore.setOnClickListener(new View.OnClickListener(){

                public void onClick(View v) {
                    if (((CheckBox) v).isChecked()) {
                        Toast.makeText(OccasionActivity.this,
                                "Checked", Toast.LENGTH_LONG).show();
                    }}
            });
            checkBox_aWeekBefore.setOnClickListener(new View.OnClickListener(){

                public void onClick(View v) {
                    if (((CheckBox) v).isChecked()) {
                        Toast.makeText(OccasionActivity.this,
                                "Checked", Toast.LENGTH_LONG).show();
                    }}
            });

            btn_create_button.setOnClickListener(new View.OnClickListener() {

                @Override
                public void onClick(View v) {
                    doOnCLickAndOnOptionSelected();

                }
            });


        }

        @SuppressLint("ValidFragment")
        public class DatePickerFragment extends DialogFragment implements DatePickerDialog.OnDateSetListener {

            @Override
            public Dialog onCreateDialog(Bundle savedInstanceState) {
                // Use the current date as the default date in the picker
                final Calendar c = Calendar.getInstance();
                int year = c.get(Calendar.YEAR);
                int month = c.get(Calendar.MONTH);
                int day = c.get(Calendar.DAY_OF_MONTH);

                // Create a new instance of DatePickerDialog and return it
                return new DatePickerDialog(getActivity(), this, year, month, day);
            }

            public void onDateSet(DatePicker view, int year, int month, int day) {
                Date = new StringBuilder().append(year).append("-").append(month + 1).append("-").append(day).append(" ").toString();
                btn_Date.setText(new StringBuilder().append(day).append("-").append(month + 1).append("-").append(year).append(" ").toString());
            }
        }

    }

Here i need to show the delete icon only when the details are updated.....i need to hide that icon while creating an event...creating an event code is in "protected void on Create"....Where i need to add this hide method...i tried this inside this create method but it shows an error...Please help me

Answer 1

Simply create your menu:

boolean eventUpdated = true/false;

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.menu_occasion, menu);
    return true;
}

and set visibility according your condition:

@Override
public boolean onPrepareOptionsMenu(Menu menu) {
    menu.getItem(R.id.menu_cancel_event).setVisible(eventUpdated);
    return true;
}

Call invalidateOptionsMenu() everytime condition changes to refresh menu.

Answer 2

A MenuItem is not a regular view that's part of your layout. Its something special, completely different. Your code returns null for item and that's causing the crash. What you need instead is to do:

MenuItem item = menu.findItem(R.id.addAction);

Then get a MenuItem pointing to such item, call setVisible() on it to adjust its visibility and then call

invalidateOptionsMenu()

on your activity so the ActionBar menu is adjusted accordingly.

Answer 3

Try below code,

public class MainActivity extends Activity {
Menu menu;

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    this.menu = menu;
    getMenuInflater().inflate(R.menu.menu_act_app_home_new, menu);
    return true;
}

void show(){
    menu.findItem(R.id.menu_cancel_event).setVisible(true);
}

void hide(){
    menu.findItem(R.id.menu_cancel_event).setVisible(false);
}
}

Let me know if this works for you...

And marks it as an answer so it would be useful to others