How to disable button after it is clicked once in a day and reenable the button on the next day?

Saving a timestamp in SharedPreferences should suffice. If you're worried about security, you could use a crypto library (see this SO link) and save the datetime in a file, but that is most likely overkill.\n\nTo use the SharedPreferences with Dates, it it easy enough to use a formatted string (with day-precision) of a java.util.Date object. \n\nFor example, to persist a java.util.Date class to SharedPreferences as a formatted string:\n\n//pre-condition: variable \"context\" is already defined as the Context object in this scope\nString dateString = DateFormat.format(\"MM/dd/yyyy\", new Date((new Date()).getTime())).toString();\nSharedPreferences sp = context.getSharedPreferences(\"<your-app-id>\", Context.MODE_PRIVATE);\nEditor editor = sp.edit();\neditor.putString(\"<your-datetime-label>\", dateString);\neditor.commit();\n\n\nTo retrieve the dateTime again from SharedPreferences, you could try:\n\n//pre-condition: variable \"context\" is already defined as the Context object in this scope\nSharedPreferences sp = context.getSharedPreferences(\"<your-app-id>\", Context.MODE_PRIVATE);\nString savedDateTime = sp.getString(\"<your-datetime-label>\", \"\");\nif (\"\".equals(savedDateTime)) {\n //no previous datetime was saved (allow button click)\n //(don't forget to persist datestring when button is clicked)\n} else {\n String dateStringNow = DateFormat.format(\"MM/dd/yyyy\", new Date((new Date()).getTime())).toString();\n //compare savedDateTime with today's datetime (dateStringNow), and act accordingly\n if(savedDateTime.equals(dateStringNow){\n //same date; disable button\n } else {\n //different date; allow button click\n }\n}\n\n\nThis makes it rather simple to persist dates and check them again.\nYou could also store the System's timeInMillis, and use a long value in shared preferences instead of a string representation of the date.",

When the button is pressed, you can save the current time into SharedPreferences. One way of gathering the current time would be to use System.currentTimeMillis. \n\nThen during onResume of your activity or after an interval of a custom timer, you could get the stored time from the Shared preferences, subtract it from the current time and then see if that number if larger than a day.\n\nif (now - storedTime > DateUtils. DAY_IN_MILLIS) {\n b.setEnabled(true);\n}\n",