Question

So I have these five buttons that I want to be always present in all activities, sort of shortcut buttons to other activities. So i created a separate xml layout for this and just included them in the other activity layouts. I also created a class with corresponding methods that will handle the button clicks.

Now my problem is that I don’t know how to use/declare this class in my activities. When I try to run my app, logcat gives me an error that it couldn’t find the method handling the click.

How can I do that?

Here’s my buttons handler class:

package com.meralco.pms;

import android.app.Activity;
import android.content.Intent;
import android.view.View;
import android.widget.Toast;

public class ButtonsHandler extends Activity{

protected void startSin() {
    Intent launch = new Intent(this, SinActivity.class);
    startActivity(launch);
}
protected void startCity() {
    Intent launch = new Intent(this, CityActivity.class);
    startActivity(launch);
}

protected void startHelp() {
    Intent launch = new Intent(this, HelpActivity.class);
    startActivity(launch);

}
protected void startAll() {
    Intent launch = new Intent(this, AllActivity.class);
    startActivity(launch);

}
protected void startDate() {
    Intent launch = new Intent(this, DateActivity.class);
    startActivity(launch);

}
public void buttonClick(View v) {
    switch(v.getId())
      {
      case R.id.button_sin:
          Toast.makeText(v.getContext(), "SIN" , Toast.LENGTH_SHORT).show();
          startSin();
          break;
      case R.id.button_city:
          startCity();
          Toast.makeText(v.getContext(), "CITY" , Toast.LENGTH_SHORT).show();
          break;
      case R.id.button_date:
          startDate();
          Toast.makeText(v.getContext(), "DATE" , Toast.LENGTH_SHORT).show();
          break;
      case R.id.button_all:
          startAll();
          Toast.makeText(v.getContext(), "ALL" , Toast.LENGTH_SHORT).show();
          break;
      case R.id.button_help:
          startHelp();
          Toast.makeText(v.getContext(), "HELP" , Toast.LENGTH_SHORT).show();
          break;
      }
}
}

I think I am missing constructors. Am I heading the right way or I got it totally wrong? TIA!

Answer 1

I would change your ButtonsHandler to extend Fragment instead of Activity. Then you can include this fragment in all the rest of your activities. They will have to extend FragmentActivity in order to host your ButtonsHandler fragment and the layout files will reference com.meralco.pms.ButtonsHandler as a fragment.

In order to support fragments in Android versions before 3.0, you’ll want to use the Android Compatibility Library: http://developer.android.com/sdk/compatibility-library.html

You’ll also want to read up about Fragments: http://developer.android.com/guide/topics/fundamentals/fragments.html

They are the recommended way for Android applications to re-use UI components like in this case:

A Fragment represents a behavior or a portion of user interface in an Activity. You can combine multiple fragments in a single activity to build a multi-pane UI and reuse a fragment in multiple activities. You can think of a fragment as a modular section of an activity, which has its own lifecycle, receives its own input events, and which you can add or remove while the activity is running (sort of like a “sub activity” that you can reuse in different activities).

With regards to your buttons, you’ll want to hook up listeners like so:

Button helpButton = (Button) findViewById(R.id.button_help);
helpButton.setOnClickListener(new View.OnClickListener() {
    public void onClick(View v) {
        startHelp();
        Toast.makeText(v.getContext(), "HELP" , Toast.LENGTH_SHORT).show();                   
    }
});