Need assistance with onclick [duplicate]

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• I would like to set my variables at the top of my class instead of in the method 4 answers

First of all hi, I am building an android app and basicly I want it to count tapping on screen(anywhere), now i tried to put the relative layout to have clickable true and my 1 textview the same, but when i try to start the activity the app crashes, I would like it to show time, lets say 30 seconds and then to count tapps for these 30 seconds.

> XML <RelativeLayout
> xmlns:android="http://ift.tt/nIICcg"
>     xmlns:tools="http://ift.tt/LrGmb4"
>     android:layout_width="match_parent"
>     android:layout_height="match_parent"
>     tools:context="com.orion.peky.thetapgame.Game"
> >
> 
>     <TextView
>         android:text="Tap to start"
>         android:layout_width="wrap_content"
>         android:layout_height="wrap_content"
>         android:layout_centerVertical="true"
>         android:layout_centerHorizontal="true"
>         android:textSize="50dp"
>         android:textColor="#FFFFFFFF"
>         android:id="@+id/tekst" />
> 
> </RelativeLayout>
> 
> MAIN package com.orion.peky.thetapgame;
> 
> import android.app.Activity;
> import android.os.Bundle; 
> import android.view.Menu; 
> import android.view.MenuItem; 
> import android.view.View;
> import android.widget.TextView;
> 
> 
> public class Game extends Activity {
> 
>     @Override
>     protected void onCreate(Bundle savedInstanceState) {
>         super.onCreate(savedInstanceState);
>         setContentView(R.layout.activity_game);
>     }
>     TextView tekst=(TextView)findViewById(R.id.tekst);
>     int brojac=0;
> 
>     public void broji(View view){
>         brojac=brojac+1;
>         tekst.setText("Tapped "+brojac+" times");
>     } }

I hope you can help me make this :D