Question

I have an Activity that, for each widget in the layout, I call setOnClickListener() to assign my OnClick() handler. In my OnClick() handler I use a switch statement to execute the desired code for each button based on the View parameter’s ID. Is there a way to assign a default handler to the main view instead of having to make individual listener assignment calls for each widget in the view?

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UPDATE

Thanks to kcoppock’s starting sample I have coded up a complete implementation of a class that has a static method that sets the click handler for all View elements in an Activity to a common click handler. This is for those situations where you have a simple layout and you want to do all the event handling in a common click listener event that uses a switch statement based on the View parameter object’s ID. To use it from an Activity, just call Misc.setDefaultClickHandler(this, this). Naturally your Activity needs to implement the View.OnclickListener interface.

package {put your package name here};

import android.app.Activity;
import android.view.View;
import android.view.ViewGroup;

public class Misc {

    public Misc() {
        super();
    }

    // Returns the root view for a given activity.
    public static View getRootView(Activity activity) {
        return activity.findViewById(android.R.id.content).getRootView();
    }

    private static void assignClickHandler(View root, View.OnClickListener theOnClickListener) {

        // Is it a View or a View group?
        if (root instanceof ViewGroup) {

            // It's a ViewGroup, process all it's children.
            ViewGroup vg = (ViewGroup) root;

            for(int i = 0; i < vg.getChildCount(); i++) 
                // Make recursive call.
                assignClickHandler(vg.getChildAt(i), theOnClickListener);
        } 
        else 
        {
            // Child is a View.  Set the desired context for the click handler.
            root.setOnClickListener(theOnClickListener);
        }
    }

    public static void setDefaultClickHandler(Activity activity, View.OnClickListener theOnClickListener) {
        assignClickHandler(getRootView(activity), theOnClickListener);
    }
}

— roschler

Answer 1

Not to my knowledge, but you could just use a loop, something like this:

ViewGroup root = findViewById(R.id.my_root_layout);
final Context context = this;
assignClickHandler(root);

public void assignClickHandler(int root) {
    for(int i = 0; i < root.getChildCount(); i++) {
        if(root.getChildAt(i) instanceof ViewGroup) {
            assignClickHandler(root.getChildAt(i));
        }
        else {
            (root.getChildAt(i)).setOnClickListener(context);
        }
    }
}

Note it calls recursively for any nested layouts within as well. I haven’t tested this so I might have messed up some syntax, but that idea should work, if you’re just looking to avoid manually setting every one.