CODEWITHSUNDEEP
javaandroidxml
RichFounders
RichFounders

Reputation: 169

It Is fine to define all Widget ID with same Variable?

I mean is like this

button = (Button)findViewById(R.id.button1);
button = (Button)findViewById(R.id.button2);
button = (Button)findViewById(R.id.button3);
button = (Button)findViewById(R.id.button4);
button = (Button)findViewById(R.id.button5);    
button.setOnClickListener(new View.OnClickListener() {

            public void onClick(View v){ 

                //Do same logic              

            }
         });
     }

it is possible to define like that? or it can causes force close?

and one question again, it is okay to use copying ID from current xml to another xml? i mean the xml was different but the Widget and ID is same, and define the ID in diferrent class. Because it is more simple to copying than make the Same widget with new Id, it is okay?

example :

so in activityone.xml

i had this

enter image description here

so i was copy the widget to activitytwo.xml so they have a same Widget and ID

enter image description here

it is okay if i do like that?

Upvotes: 0

Views: 129

Answers (2)

Akash Thakare
Akash Thakare

Reputation: 22972

For that you should have single listener but five different buttons (Objects). Currently you are assigning every button one by one to same button reference. In that way your button will have R.id.button5 and in further code you won't have reference to your previous buttons butons1-4. So, while you add listener to the button you are actually adding listener to only button 5 and any other buttons will not have that listener.

First of all you need five different buttons and you should create class which implement the listener and add instance of that listener to your setOnClicklistener method or in a better way you can just specify android:onClick="onClick" in your xml and add onClick method in your activity.

FOR EXAMPLE :

//.. on create
Button button1 = (Button)findViewById(R.id.button1);
Button button2 = (Button)findViewById(R.id.button2);
Button button3 = (Button)findViewById(R.id.button3);
Button button4 = (Button)findViewById(R.id.button4);
Button button5 = (Button)findViewById(R.id.button5); 

ListenerClass listener = new ListenerClass();
button1.setOnClickListener(listener);
button2.setOnClickListener(listener);
//..and so on

//Create class
public class ListenerClass implements View.OnClickListener {

     //...
     @Override
     public void onClick(View view) {
          //You can determine which button is clicked by view.getId()    
          //Add logic here
     } 
 }

OR

public class YourActivity implements View.OnClickListener {

   //...on create
   button1.setOnClickListener(this);
   button2.setOnClickListener(this);
   //..and so on
   //...
   @Override
   public void onClick(View view) {
       //You can determine which button is clicked by view.getId()    
       //Add logic here
   }
}

it is okay to use copying ID from current xml to another xml?

Yes it is fine but you should avoid using that as it may create confusion in a long run. In a wide project working with a team can create problem in understanding that. Other than that you can have same id because when you call findViewById it will refer to the current view and does not get influenced by ids of other views.

Upvotes: 0

Zarwan
Zarwan

Reputation: 5777

That will only set the listener for button5. Every time you assign button you lose the previous assignment, so when you set the listener the variable button doesn't know that it used to be pointing to button1 to 4.

So no, it will not work.

I put a comment about your second question.

Upvotes: 1

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