How to set a button visible from another activity in android

Question

I have a very simple problem. I have a invisible button in my Main Activity, and I have a second Activity that makes that button visible. In the second activity I don´t have a p

Answer 1

Solve the problem. In the second Activity a have a static boolean variable that begins false. Once the oncreate() in the second Activity is call, the boolean variable is change to true. onresume() in MainActivity i check if the boolean variable is true, and change the visibility of the button.

SecondActivity

public static boolean showButton = false;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    showButton = true;

}

MainActivity

@Override
protected void onResume() {
    if ( Display.showButton){
        mMyButtonToBeHidden.setVisibility(View.VISIBLE);
    }
    super.onResume();
}