通过AsyncTask实现上传界面进度条、通知栏进度条同时刷新。
之前做一个项目，要求上传过程中，同时刷新上传界面中进度条和通知栏下拉页面中进度条。
一、我之前的做法是，在具体的下载方法中不停向两者发消息，通知更新进度。粗糙代码如下：
while ((len = is.read(buffer)) != -1) {
outStream.write(buffer, 0, len);
// 更新进度条
uploadSize += len;
progress = (int) (uploadSize * 100 / tempFile.length());
sendMessage(progress, tempFile);
}
private void sendMessage(int progress, File tempFile) {
if (handler_1 != null) {
Message msg = new Message();
msg.obj = tempFile.getPath();
msg.what = Constant.UPLOADING;
msg.arg1 = progress;
handler_1.sendMessage(msg);
}
if (handler_2 != null) {
Message msg = new Message();
msg.obj = tempFile.getPath();
msg.what = Constant.UPLOADING;
msg.arg1 = progress;
handler_2.sendMessage(msg);
}
}
这样做的问题是：界面非常卡，下拉通知栏基本没反应，点击上传界面也没反应。
可能原因：消息发的太多，太频繁。
二、后来自己尝试用AsyncTask实现文件复制模拟上传/下载过程，两者同时刷新，界面不卡了，下拉通知栏也不卡。但是仍有一个问题：整个文件复制过程很漫长。
代码涉及主要文件：AsyncTaskUpdateProgressBarActivity.java、DownloadAsyncTask.java、AndroidManifest.xml、notification.xml
具体代码如下：
AsyncTaskUpdateProgressBarActivity.java
package com.test;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import android.app.Activity;
import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Intent;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ProgressBar;
import android.widget.RemoteViews;
import android.widget.TextView;
import android.widget.Toast;
public class AsyncTaskUpdateProgressBarActivity extends Activity {
private static final String savePath = "/mnt/sdcard/dir/test/WinRAR.exe";
private static final String src = "/mnt/sdcard/WinRAR.exe";
private ProgressBar progressBar;
private TextView text;
private Button btn;
private NotificationManager nm;
private RemoteViews rv;
private Notification notification;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
progressBar = (ProgressBar)findViewById(R.id.progress_bar);
text = (TextView)findViewById(R.id.text);
//初始化通知栏RemoteViews中进度条
nm = (NotificationManager)getSystemService(NOTIFICATION_SERVICE);
Intent intent = new Intent();
PendingIntent pIntent = PendingIntent.getActivity(AsyncTaskUpdateProgressBarActivity.this, 0, intent, 0);
rv = new RemoteViews(getPackageName(), R.layout.notification);
rv.setProgressBar(R.id.task_progress, 100, 0, false);
notification = new Notification(R.drawable.icon, "正在上传", android.os.SystemClock.uptimeMillis());
notification.defaults = Notification.DEFAULT_SOUND;
notification.flags = Notification.FLAG_AUTO_CANCEL|Notification.FLAG_ONGOING_EVENT|Notification.FLAG_ONLY_ALERT_ONCE;
notification.contentIntent = pIntent;
notification.contentView = rv;
final Object[] params = {src, progressBar, text, AsyncTaskUpdateProgressBarActivity.this, notification, nm};
btn = (Button)findViewById(R.id.btn);
btn.setOnClickListener(new OnClickListener()
{
@Override
public void onClick(View v)
{
//执行下载，更新界面进度条和通知中进度条
DownloadAsyncTask downloadTask = new DownloadAsyncTask();
downloadTask.execute(params);
}
});
}
}
DownloadAsyncTask.java
package com.test;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import android.app.Notification;
import android.app.NotificationManager;
import android.content.Context;
import android.os.AsyncTask;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;
public class DownloadAsyncTask extends AsyncTask
{
private static final String savePath = "/mnt/sdcard/dir/test/WinRAR.exe";
private ProgressBar progressBar;
private TextView text;
private Context context;
private Notification notification;
private NotificationManager nm;
@Override
protected Void doInBackground(Object... params)
{
String src = (String)params[0];
progressBar = (ProgressBar)params[1];
text = (TextView)params[2];
context = (Context)params[3];
notification = (Notification)params[4];
nm = (NotificationManager)params[5];
FileOutputStream fos = null;
try
{
FileInputStream fis = new FileInputStream(src);
File f = new File(savePath);
if(!f.exists())
{
f.createNewFile();
}
fos = new FileOutputStream(f);
long fileLength = fis.available();
publishProgress(0);
int numRead = -1;
byte buf[] = new byte[1024];
float downloadSize = 0;
int progress = 0;
while((numRead = fis.read(buf)) != -1)
{
fos.write(buf, 0, numRead);
downloadSize += numRead;
progress = (int)(downloadSize* 100/fileLength);
publishProgress(progress);
//更新通知中进度条
notification.contentView.setProgressBar(R.id.task_progress, 100, progress, false);
nm.notify(0, notification);
}
}
catch (FileNotFoundException e)
{
e.printStackTrace();
}
catch (IOException e)
{
e.printStackTrace();
}
return null;
}
@Override
protected void onPreExecute()
{
super.onPreExecute();
}
@Override
protected void onPostExecute(Void result)
{
super.onPostExecute(result);
text.setText("onPostExecute");
Toast.makeText(context, "下载完成", Toast.LENGTH_LONG).show();
nm.cancel(0);
}
@Override
protected void onProgressUpdate(Integer... values)
{
super.onProgressUpdate(values);
progressBar.setProgress(values[0]);
}
@Override
protected void onCancelled()
{
super.onCancelled();
}
}
AndroidManifest.xml
android:versionCode="1"
android:versionName="1.0">
notification.xml
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:padding="10dip">
android:layout_width="fill_parent"
android:layout_height="8dip"
android:layout_marginTop="3dip"
android:max="100"
style="?android:attr/progressBarStyleHorizontal" />
已解决的问题：整个界面流畅
存在的问题：整个复制过程用时变长了。
望有高手指点，是不是用AsyncTask解决同时刷新进度条不太合适，还是具体处理过程中出了什么问题？