Android 进度条ProgressBar和消息传递Handler

[android]代码库

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.widget.Button;
import android.widget.ProgressBar;
import android.widget.TextView;

/**
 * 进度条ProgressBar，消息传递Handler
 */
public class EX04_17 extends Activity {
	private TextView mTextView01;
	private Button mButton01;
	private ProgressBar mProgressBar01;
	public int intCounter = 0;

	/* 自定义Handler讯息代码，用以作为识别事件处理 */
	protected static final int GUI_STOP_NOTIFIER = 0x108;
	protected static final int GUI_THREADING_NOTIFIER = 0x109;

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.main);
		mButton01 = (Button) findViewById(R.id.myButton1);
		mTextView01 = (TextView) findViewById(R.id.myTextView1);
		mProgressBar01 = (ProgressBar) findViewById(R.id.myProgressBar1);
		mProgressBar01.setIndeterminate(false);

		mButton01.setOnClickListener(new Button.OnClickListener() {
			@Override
			public void onClick(View v) {
				// TODO Auto-generated method stub
				mTextView01.setText(R.string.str_progress_start);
				/* 将隐藏的ProgressBar显示出来 */
				mProgressBar01.setVisibility(View.VISIBLE);
				/* 指定Progress为最多100 */
				mProgressBar01.setMax(100);
				/* 初始Progress为0 */
				mProgressBar01.setProgress(0);
				/* 起始一个线程 */
				new Thread(new Runnable() {
					public void run() {
						/* 预设0至9，共执行10次的循环叙述 */
						for (int i = 0; i < 10; i++) {
							try {
								intCounter = (i + 1) * 20;
								Thread.sleep(1000);
								/* 当Thread执行5秒后显示执行结束 */
								if (i == 4) {
									/* 以Message对象，传递参数给Handler */
									Message m = new Message();
									/* 以what属性指定User自定义 */
									m.what = EX04_17.GUI_STOP_NOTIFIER;
									EX04_17.this.myMessageHandler
											.sendMessage(m);
									break;
								} else {
									Message m = new Message();
									m.what = EX04_17.GUI_THREADING_NOTIFIER;
									EX04_17.this.myMessageHandler
											.sendMessage(m);
								}
							} catch (Exception e) {
								e.printStackTrace();
							}
						}
					}
				}).start();
			}
		});
	}

	/* Handler建构之后，会聆听传来的讯息代码 */
	Handler myMessageHandler = new Handler() {
		public void handleMessage(Message msg) {
			switch (msg.what) {
			/* 当取得识别为 离开线程时所取得的讯息 */
			case EX04_17.GUI_STOP_NOTIFIER:
				/* 显示执行终了 */
				mTextView01.setText(R.string.str_progress_done);
				/* 设定ProgressBar Widget为隐藏 */
				mProgressBar01.setVisibility(View.GONE);
				Thread.currentThread().interrupt();
				break;
			/* 当取得识别为 持续在线程当中时所取得的讯息 */
			case EX04_17.GUI_THREADING_NOTIFIER:
				if (!Thread.currentThread().isInterrupted()) {
					mProgressBar01.setProgress(intCounter);
					/* 将显示进度显示于TextView当中 */
					mTextView01
							.setText(getResources().getText(
									R.string.str_progress_start)
									+ "("
									+ Integer.toString(intCounter)
									+ "%)\n"
									+ "Progress:"
									+ Integer.toString(mProgressBar01
											.getProgress())
									+ "\n"
									+ "Indeterminate:"
									+ Boolean.toString(mProgressBar01
											.isIndeterminate()));
				}
				break;
			}
			super.handleMessage(msg);
		}
	};
}