Comparing two Spinner values

Question

I want to compare two Spinner values and, according to them, I want to display a result.
I have tried the following code, but everytime I run the application it does not show the expected result.

How to compare those values?

Here is the code

public class MyApp extends Activity implements OnItemSelectedListener {

    Spinner temp1,temp2;
    TextView t1,t2,t3;
    EditText itemp;
    Integer i,o,conv;
    Double tc,tk,tf;
    String sel1,sel2;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_calculator);

        t1=(TextView)findViewById(R.id.t1);
        t2=(TextView)findViewById(R.id.t2);
        t3=(TextView)findViewById(R.id.otemp);
        itemp=(EditText)findViewById(R.id.itemp);

        temp1=(Spinner)findViewById(R.id.temp);
        ArrayAdapter<CharSequence> adapter=ArrayAdapter.createFromResource(this,R.array.temperature,android.R.layout.simple_spinner_item);
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        temp1.setAdapter(adapter);
        temp1.setOnItemSelectedListener(this);

        temp2=(Spinner)findViewById(R.id.temp2);
        ArrayAdapter<CharSequence> adapter2=ArrayAdapter.createFromResource(this,R.array.temperature,android.R.layout.simple_spinner_item);
        adapter2.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        temp2.setAdapter(adapter2);
        temp2.setOnItemSelectedListener(this);

        tk=Double.parseDouble(itemp.getText().toString());
        if (sel1.equals("MyappVer") && sel2.equals("MYAPPVER")){
        t3.setText("="+tk);
        }

    }

    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
        // On selecting a spinner item
        Spinner temp1=(Spinner)parent;
        Spinner temp2=(Spinner)parent;
        if (temp1.getId()==R.id.temp) {
            String item1 = parent.getItemAtPosition(position).toString();

            t1.setText(item1);
            sel1=item1;
        }
        if (temp2.getId()==R.id.temp2) {
            String item2 = parent.getItemAtPosition(position).toString();

            t2.setText(item2);
            sel2=item2;
        }

    }

    public void onNothingSelected(AdapterView<?> arg0) {
        // TODO Auto-generated method stub

    }

}

When I remove these lines the app works, but I need to compare those Spinner values

if (sel1.equals("MyappVer") && sel2.equals("MYAPPVER")){
            t3.setText("="+tk);
        }

Is something wrong with this implementation?

Logcat

08-04 14:48:28.651  13541-13541/com.combud.calcthree.compencalculator     E/AndroidRuntime﹕ FATAL EXCEPTION: main
    java.lang.RuntimeException: Unable to start activity     ComponentInfo{com.combud.calcthree.compencalculator/com.combud.calcthree.compenc alculator.MyApp}: java.lang.NumberFormatException: Invalid double: ""
            at     android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1968)
            at     android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1993)
            at android.app.ActivityThread.access$600(ActivityThread.java:127)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1159)
            at android.os.Handler.dispatchMessage(Handler.java:99)
            at android.os.Looper.loop(Looper.java:137)
            at android.app.ActivityThread.main(ActivityThread.java:4507)
            at java.lang.reflect.Method.invokeNative(Native Method)
            at java.lang.reflect.Method.invoke(Method.java:511)
            at     com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:978)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:745)
            at dalvik.system.NativeStart.main(Native Method)
     Caused by: java.lang.NumberFormatException: Invalid double: ""
            at java.lang.StringToReal.invalidReal(StringToReal.java:63)
            at java.lang.StringToReal.parseDouble(StringToReal.java:248)
            at java.lang.Double.parseDouble(Double.java:295)
            at     com.combud.calcthree.compencalculator.MyApp.onCreate(MyApp.java:50)
            at android.app.Activity.performCreate(Activity.java:4469)
            at     android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1052)
            at     android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1932)
            at     android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1993)
            at     android.app.ActivityThread.access$600(ActivityThread.java:127)
            at     android.app.ActivityThread$H.handleMessage(ActivityThread.java:1159)
            at android.os.Handler.dispatchMessage(Handler.java:99)

possible duplicate of [Unfortunately MyApp has stopped. How can I solve this?](http://stackoverflow.com/questions/23353173/unfortunately-myapp-has-stopped-how-can-i-solve-this) — 2Dee, Aug 04 '15 at 08:28
"When I remove these lines the app works" what happens if you keep these lines? Please also read [How do I ask a good question?](http://stackoverflow.com/help/how-to-ask) — Sufian, Aug 04 '15 at 09:26
possible duplicate of [java.lang.numberformatexception: invalid double: " "](http://stackoverflow.com/questions/18672456/java-lang-numberformatexception-invalid-double) — Sufian, Aug 04 '15 at 10:38

score 2 · Answer 1 · answered Aug 04 '15 at 07:58

2

String sel1= temp1.getSelectedItem().toString();
String sel2= temp2.getSelectedItem().toString();
if (sel1.equals("MyappVer") && sel2.equals("MYAPPVER")){
            t3.setText("="+tk);
        }

update your code with the below one. and what you want to do in your application tell me your requirement there is no meaning of writing you if statement there

answered Aug 04 '15 at 07:58

Bala Saikrupa Puram

721
1
7
28

It still not working.. application stops unfortunately – Saurabh Aug 04 '15 at 08:17
first tell me what you want to do from the code. I mean what output your expecting... – Bala Saikrupa Puram Aug 04 '15 at 08:47

Abhinav Singh Maurya · Accepted Answer · 2015-08-04T09:36:29.507

1

This is due to your sel1 and sel2 string are null at the time of

 if (sel1.equals("MyappVer") && sel2.equals("MYAPPVER")){
        t3.setText("="+tk);
        }

and you are trying to check the value on null object

Do like this

String sel1 = "",sel2 = "";

Also add the value of them before checking them like

sel1= temp1.getSelectedItem().toString();
sel2= temp2.getSelectedItem().toString();
if (sel1.equals("MyappVer") && sel2.equals("MYAPPVER")){
            t3.setText("="+tk);
        }

If you want to update these value after selection of spinner add above lines in your onItemSelected method of spinner not in onCreate method

Let me know if this helps

Edit:

According to your logcat exception is due to

Caused by: java.lang.NumberFormatException: Invalid double: ""

at line

tk=Double.parseDouble(itemp.getText().toString());

This is due to the edit text itemp is not having any value and still you are accessing data and parsing it to double which is causing that exception.

So before parsing value check the value of edit text like

String textValue = itemp.getText().toString();
  if(textValue != null && !textValue.equalIgnoreCase("")){
  tk=Double.parseDouble(textValue);
}

edited Aug 04 '15 at 09:36

answered Aug 04 '15 at 08:06

Abhinav Singh Maurya

3,313
8
33
51

What is happening now? Please let me know. – Abhinav Singh Maurya Aug 04 '15 at 08:35
The application still stops unfortunately @Abhinav Singh Maurya – Saurabh Aug 04 '15 at 08:38
Have you done what ever I have suggested above? If yes then post your log data to see the occurred exception – Abhinav Singh Maurya Aug 04 '15 at 08:56
yes i have done that suggested edits.. I have updated the post with the log cat.. @Abhinav Singh Maurya – Saurabh Aug 04 '15 at 09:15
I cannot see any logcat data in your question. Do you any event where you will check the spinner value? like button click – Abhinav Singh Maurya Aug 04 '15 at 09:18
You can see it now, the formatting was not proper, but now you can see the logcat.. And I have not use any click event. @Abhinav – Saurabh Aug 04 '15 at 09:32
Let us [continue this discussion in chat](http://chat.stackoverflow.com/rooms/85089/discussion-between-saurabh-and-abhinav-singh-maurya). – Saurabh Aug 04 '15 at 09:33
Then how to solve this exception? I want that edit text to be filled by the user of the app – Saurabh Aug 04 '15 at 09:40
Why you are taking every value on onCreate method? You should have some event to check those value. in your onCreate method those value are null and do not have any value till you fill up. and add a button where you should check those values. – Abhinav Singh Maurya Aug 04 '15 at 09:42
Because I have always done so.. Ok let me try what you have said and thank you for the help :) – Saurabh Aug 04 '15 at 09:54
If my answer is helpful, please mark it as accepted answer so that other can also take a reference if they have any problem or stuck in code like yours :) – Abhinav Singh Maurya Aug 04 '15 at 09:59
Thankyou for the help. The code is now working as expected. Thankyou :) – Saurabh Aug 04 '15 at 19:06

Comparing two Spinner values

2 Answers2