TestHandlersDriverActivity.java

package com.pinecone.technology.mcommerce.learning.android.chapter06.handler;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.util.Log;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.widget.TextView;

import com.pinecone.technology.mcommerce.learning.android.chapter06.R;

public class TestHandlersDriverActivity extends Activity {
	public static final String tag = "TestHandlersDriverActivity";

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.c06_handler_test02);
	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		super.onCreateOptionsMenu(menu);
		MenuInflater inflater = getMenuInflater(); // from activity
		inflater.inflate(R.menu.c06_menu_handler, menu);
		return true;
	}

	@Override
	public boolean onOptionsItemSelected(MenuItem item) {
		appendMenuItemText(item);
		if (item.getItemId() == R.id.menu_clear) {
			this.emptyText();
			return true;
		}
		if (item.getItemId() == R.id.menu_test_thread) {
			this.testThread();
			return true;
		}
		if (item.getItemId() == R.id.menu_test_defered_handler) {
			this.testDeferedHandler();
			return true;
		}
		return true;
	}

	private TextView getTextView() {
		return (TextView) this.findViewById(R.id.text1);
	}

	public void appendText(String abc) {
		TextView tv = getTextView();
		tv.setText(tv.getText() + "\n" + abc);
	}

	private void appendMenuItemText(MenuItem menuItem) {
		String title = menuItem.getTitle().toString();
		TextView tv = getTextView();
		tv.setText(tv.getText() + "\n" + title);
	}

	private void emptyText() {
		TextView tv = getTextView();
		tv.setText("");
	}

	private DeferWorkHandler th = null;

	private void testDeferedHandler() {
		if (th == null) {
			th = new DeferWorkHandler(this);
			this.appendText("Creating a new handler");
		}
		this.appendText("Starting to do deferred work by sending messages");
		th.doDeferredWork();
	}

	Handler statusBackHandler = null;
	Thread workerThread = null;

	private void testThread() {
		if (statusBackHandler == null) {
			statusBackHandler = new ReportStatusHandler(this);
			workerThread = new Thread(new WorkerThreadRunnable(
					statusBackHandler));
			workerThread.start();
			return;
		}
		if (workerThread.getState() != Thread.State.TERMINATED) {
			Log.d(tag, "thread is new or alive, but not terminated");
		} else {
			Log.d(tag, "thread is likely dead. starting now");
			// you have to create a new thread.
			// no way to resurrect a dead thread.
			workerThread = new Thread(new WorkerThreadRunnable(
					statusBackHandler));
			workerThread.start();
		}
	}
}