Button

import android.app.Activity;
import android.widget.FrameLayout;
import android.widget.Button;     
import android.graphics.Color;
import android.view.View;
import android.view.ViewGroup.LayoutParams;
import android.view.View.OnClickListener;
import android.view.Gravity;
import android.R;
import processing.android.CompatUtils;

Activity act;
FrameLayout fl;
Button btn1;
int btn1Id, tel;
boolean toggle;

void setup() {
  fullScreen();
  orientation(PORTRAIT);
  background(255);
  fill(0);
  textAlign(CENTER);
  textSize(35);
  text("Click on screen to show button.", width/2, height/2);
}

void draw() {
}

@ Override 
  public void onStart() {
  super.onStart();
  act = this.getActivity();
  btn1 = new Button(act);
  btn1.setTextSize(30); 
  btn1.setText("Click");
  //btn1.setHeight(55); 
  btn1.setWidth(280); 
  btn1.setX(width/2-140);
  btn1.setY(200);

  btn1.setTextColor(Color.WHITE);
  btn1.setBackgroundColor(Color.rgb(0, 150, 150));
  btn1Id = CompatUtils.getUniqueViewId();
  //btn1Id = View.generateViewId();
  btn1.setId(btn1Id);
  btn1.setVisibility(View.GONE);
  btn1.setOnClickListener(new View.OnClickListener() {
    public void onClick(View v) {
      background(255);
      text("Click on button to count.", width/2, height/3);
      tel++;
      text("You clicked "+str(tel)+" times", width/2, height/3+100);
      text("Click on screen to hide button.", width/2, height/3+200);
    }
  }
  );
  fl = (FrameLayout)act.findViewById(R.id.content);
  fl.addView(btn1, new FrameLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT, Gravity.LEFT));
}


void mousePressed() {
  act.runOnUiThread(
    new Runnable() {
    public void run() {
      Button bt = (Button)act.findViewById(btn1Id);
      if (toggle) {
        background(255);
        text("Click on button to count.", width/2, height/3);
        bt.setVisibility(View.VISIBLE);
      } else {
        background(255);
        text("Click on screen to show button.", width/2, height/2);
        bt.setVisibility(View.GONE);
        tel = 0;
      }
    }
  }
  );
  toggle =! toggle;
}