android学习——AsyncTast 异步操作和 ProgressBar

main.xml

用来模拟网络操作java

public class NetOperate {

	static public void operate(int sec){
		try {
			//当前线充休眠
			Thread.sleep(sec*1000);
		} catch (Exception e) {
			// TODO: handle exception
			e.printStackTrace();
		}
	}
}

activity 

public class ProgressAsyncTask extends AsyncTask{

	private TextView textView;
	private ProgressBar progressBar;
	
	public ProgressAsyncTask(TextView textView, ProgressBar progressBar) {
		this.textView = textView;
		this.progressBar = progressBar;
	}
	
	//开始执行异步操作时,执行次方法.
	@Override
	protected void onPreExecute() {
		// TODO Auto-generated method stub
		System.out.println(textView);
		textView.setText("异步操作开始");
	}
	//异步执行的
	@Override
	protected String doInBackground(Integer... params) {
		// TODO Auto-generated method stub
		int i=0;
		for (i=10; i<=100; i+=10) {
			//休眠 
			NetOperate.operate(1);
			//发布一个更新,调用这个方法的同时 执行 onProgressUpdate
			publishProgress(i);
		}
		return i+params[0].intValue()+"";
	}

	//异步操作执行完成后执行该法方法,一般用来返回结果
	@Override
	protected void onPostExecute(String result) {
		// TODO Auto-generated method stub
		textView.setText("异步操作结束"+result);
	}
	
	//在doInBackground方法中每调用 publishProgress()方法是会自动调用onProgressUpdate()方法
	//在ui线程中执行
	@Override
	protected void onProgressUpdate(Integer... values) {
		// TODO Auto-generated method stub
		progressBar.setProgress(values[0]);
	}
	

结果

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