for build calculate and make errors

Question

in my project for build calculate has error like this :

void findView(){

        btn_0=(Button)findViewById(R.id.btn_0);
           btn_1=(Button)findViewById(R.id.btn_1);

and cannot resolve symbol for anythings have R ,what should i do ?

Answer 1

Go to your top nav bar --> Build -- > Clean project --> Rebuild project.

Answer 2

if you are using gradle as your build tool, the problem is that the gradle is not synced with your project. and keep in mind that if you are developing in a restricted country, try using a proxy while syncing the gradle.

Answer 3

i think gradle is not synced with your project. that's why it giving error that cannot resolve symbol for anythings have R

and R is autogenerated and contains all IDs from your controls of layouts

so Build -- > Clean project --> Rebuild project.

to clean project

Answer 4

Build -- > Clean project --> Rebuild project and run your project again