App crashes on clicking export data option of multimeter

[neel1998]

Actual Behaviour
App crashes on clicking export data option of multimeter

Expected Behaviour
App should not crash and a log file should be created

Steps to reproduce it

1. Record data in multimeter
2. Pause and select export data option

LogCat for the issue
2019-05-31 12:45:57.070 23742-23742/io.pslab E/AndroidRuntime: FATAL EXCEPTION: main
Process: io.pslab, PID: 23742
java.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.io.File.exists()' on a null object reference
at io.pslab.others.CSVLogger.writeCSVFile(CSVLogger.java:83)
at io.pslab.activity.MultimeterActivity.onOptionsItemSelected(MultimeterActivity.java:428)
at android.app.Activity.onMenuItemSelected(Activity.java:3469)
at android.support.v4.app.FragmentActivity.onMenuItemSelected(FragmentActivity.java:436)
at android.support.v7.app.AppCompatActivity.onMenuItemSelected(AppCompatActivity.java:196)
at android.support.v7.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:109)
at android.support.v7.view.WindowCallbackWrapper.onMenuItemSelected(WindowCallbackWrapper.java:109)
at android.support.v7.app.ToolbarActionBar$2.onMenuItemClick(ToolbarActionBar.java:64)
at android.support.v7.widget.Toolbar$1.onMenuItemClick(Toolbar.java:204)
at android.support.v7.widget.ActionMenuView$MenuBuilderCallback.onMenuItemSelected(ActionMenuView.java:781)
at android.support.v7.view.menu.MenuBuilder.dispatchMenuItemSelected(MenuBuilder.java:840)
at android.support.v7.view.menu.MenuItemImpl.invoke(MenuItemImpl.java:158)
at android.support.v7.view.menu.MenuBuilder.performItemAction(MenuBuilder.java:991)
at android.support.v7.view.menu.MenuPopup.onItemClick(MenuPopup.java:128)
at android.widget.AdapterView.performItemClick(AdapterView.java:318)
at android.widget.AbsListView.performItemClick(AbsListView.java:1158)
at android.widget.AbsListView$PerformClick.run(AbsListView.java:3153)
at android.widget.AbsListView$3.run(AbsListView.java:4068)
at android.os.Handler.handleCallback(Handler.java:790)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:164)
at android.app.ActivityThread.main(ActivityThread.java:6626)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:811)

Screenshots of the issue

Would you like to work on the issue?
yes

[neel1998]

@CloudyPadmal why do we have a pause button? Shouldn't it be made like other devices, where we have a stop button and clicking on it creates a csv file of logged data?

[CloudyPadmal]

@neel1998 yes, it should be a stop button

[neel1998]

@CloudyPadmal i am thinking of inheriting multimeter from PSLab sensor class to avoid redundancy . Does it sound right?

[CloudyPadmal]

That would be hard. As PSLab Sensor class got graphs and all which doesn't come with Multimeter. We can stick with the existing activity for Multimeter.

[neel1998]

@CloudyPadmal but if we want to show log data of multimeter in log data activity and playback that data.. That would become complex using current class, since realm data storing and playing back is already there in PSLab sensor , i think we can use it. This is what i think. Please give your suggestion

[neel1998]

@CloudyPadmal to resolve the #1373 I was thinking of recording data at certain time interval (say 500 ms) when record button is pressed. We will record the data of the element to which the multimeter knob is pointing .Does this sound okay ?

[neel1998]

Also should i remove the show logged data option from multimeter menu since we are not displaying multimeter logs in datalogger activity

[CloudyPadmal]

@CloudyPadmal but if we want to show log data of multimeter in log data activity and playback that data.. That would become complex using current class, since realm data storing and playing back is already there in PSLab sensor , i think we can use it. This is what i think. Please give your suggestion

If that's the case, best thing is to make a super class with all the graph and data storing functionalities and have PSLabSensor class inherit that.

[CloudyPadmal]

@CloudyPadmal to resolve the #1373 I was thinking of recording data at certain time interval (say 500 ms) when record button is pressed. We will record the data of the element to which the multimeter knob is pointing .Does this sound okay ?

Let's give user the option to set recording interval from configurations

[neel1998]

@CloudyPadmal but if we want to show log data of multimeter in log data activity and playback that data.. That would become complex using current class, since realm data storing and playing back is already there in PSLab sensor , i think we can use it. This is what i think. Please give your suggestion

If that's the case, best thing is to make a super class with all the graph and data storing functionalities and have PSLabSensor class inherit that.

Do we actually need to show multimeter logs in data logger activity. I don't see any use of replaying multimeter data

[neel1998]

@CloudyPadmal to resolve the #1373 I was thinking of recording data at certain time interval (say 500 ms) when record button is pressed. We will record the data of the element to which the multimeter knob is pointing .Does this sound okay ?

Let's give user the option to set recording interval from configurations

Should i open another issue regarding this or work with the already open one with continuous logging?

[CloudyPadmal]

@neel1998 , let's see. May be we can plot the values in a graph in a timely manner? 🤔 That way we can replay. And open a new issue for the configuration part and work on it..