摘要:Java源码,Android源码,多线程,断点下载 android多线程断点下载，通过本Android下载实例，可了解到以下知识技巧：实时得到文件下载的长度，设置获取实体数据的范围、获取文件已下载文件长度、原始文件长度、线程数、本地保存文件、缓存各线程下载的长度、每条线程下载的长度、获取线程数、获取文件大孝更新指定线程最后下载的位置、构建文件下载器、保存记录文件、根据响应获取文件大孝监听下载数量的变化,如果不需要了解实时下载的数量,可以设置为null、循环判断是否下载完毕等基础知识。
这里请注意，对于UI控件的更新只能由主线程(UI线程)负责，如果在非UI线程更新UI控件，更新的结
2022-05-17 14:42:47
83KB
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根据网上寻找的资料，加上自己的整合，打包的一个Android多线程下载。可以实现断点下载，暂停继续取消下载，能够显示现在已完成大小，文件大小，完成度，下载速度等。使用方法如下：
public class MainActivity extends Activity implements OnClickListener,DownloadListener{
private static final String TAG = "MainActivity";
private static final String SD_PATH = Environment.getExternalStorageDirectory().getPath();
private boolean isPause = false;
private MultiThreadDownload multiThreadDownload ;
private Button buttonDownload;
private Button buttonCancel;
private TextProgressBar progressBarTest;//可以使用普通的进度，该进度条是可以显示现在完成度
private TextView textInfo;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);//布局文件就是两个简单的按钮一个用于暂停继续下载，一个用于取消任务，还有一个文本用于显示已完成，文件大小，下载完成度，下载速度等信息以及一个进度条。
//http://d1.apk8.com:8020/game/plantsvszombies2.apk
buttonDownload = (Button)findViewById(R.id.buttonDownload);
buttonDownload.setText("单击下载");
buttonDownload.setOnClickListener(this);
progressBarTest = (TextProgressBar) findViewById(R.id.progressBarTest);
textInfo = (TextView) findViewById(R.id.textInfo);
buttonCancel = (Button) findViewById(R.id.buttonCancel);
buttonCancel.setOnClickListener(this);
}
@Override
public void onClick(View v) {
String downloadUrl = "http://dldir1.qq.com/invc/qqpinyin/QQInput4.1_1133(1001).apk";
String savePath = SD_PATH+File.separator+"downloadHelper"+File.separator;
String fileName = "QQInput.apk";
switch(v.getId()){
case R.id.buttonDownload:
if(!isPause){
multiThreadDownload = new MultiThreadDownload(MainActivity.this,downloadUrl, savePath, fileName, this);
multiThreadDownload.start();
buttonDownload.setText("下载...");
isPause = true;
}else{
buttonDownload.setText("暂停...");
isPause = false;
multiThreadDownload.onPause();
multiThreadDownload = null;
}
break;
case R.id.buttonCancel:
if(multiThreadDownload==null){
multiThreadDownload = new MultiThreadDownload(MainActivity.this,downloadUrl, savePath, fileName, this);
}
Log.d(TAG, ""+multiThreadDownload.isDownload());
if(multiThreadDownload.isDownload()){
multiThreadDownload.onCancel();
isPause = false;
}
multiThreadDownload = null;
break;
}
}
private Handler multiHandler = new Handler(){
@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
if(msg.what==1){
Bundle data = msg.getData();
float downloadSpeed = data.getFloat("downloadSpeed");
boolean speedHigh = false;
if(downloadSpeed>500){
speedHigh = true;
downloadSpeed/=1024;
}
progressBarTest.setProgress(data.getInt("completedSize"));
textInfo.setText(String.format("已完成：%.2fMB", data.getInt("completedSize")/1024f/1024)+"/"+
String.format("总大小：%.2fMB", data.getInt("fileSize")/1024f/1024)+"\n"+
String.format("进度：%.2f%%", data.getBoolean("isCompleted")?100.00:data.getFloat("downloadPercent"))+"/"+
String.format(speedHigh?"速度：%.2fM/S":"速度：%.2fKB/S", downloadSpeed));
if(data.getBoolean("isCompleted")){
buttonDownload.setText("下载完成");
textInfo.setText("下载完成");
}
}
}
};
@Override
public void onDownloading(boolean isCompleted,boolean isPause,boolean isCancel,int fileSize,int completedSize,int downloadedSize,float downloadPercent, float downloadSpeed) {
Log.d("MainActivity", isCompleted+"||"+isPause+"||"+completedSize+"||"+downloadedSize+"||"+downloadPercent+"||"+downloadSpeed);
Message message = Message.obtain();
message.what = 1;
Bundle data = new Bundle();
data.putBoolean("isCancel", isCancel);
data.putBoolean("isCompleted", isCompleted);
data.putInt("fileSize", fileSize);
data.putInt("completedSize", completedSize);
data.putInt("downloadedSize", downloadedSize);
data.putFloat("downloadPercent", downloadPercent);
data.putFloat("downloadSpeed", downloadSpeed);
message.setData(data);
multiHandler.sendMessage(message);
}
@Override
public void onBeforeDownload(boolean isCompleted,boolean isPause,boolean isCancel,int fileSize){
progressBarTest.setMax(fileSize);
}
@Override
public void onAfterDownload(boolean isCompleted,boolean isPause,boolean isCancel,int fileSize){
}
@Override
public void onPause(boolean isCompelted,boolean isPause,boolean isCancel,int fileSize,int completedSize,int downloadedSize,float downloadPercent,float downloadSpeed){
textInfo.setText("暂停...");
Log.d(TAG, "暂停...");
}
@Override
public void onCancelDownload(){
progressBarTest.setProgress(0);
textInfo.setText("下载取消");
buttonDownload.setText("重新下载");
}
}
2022-03-10 19:42:52
22KB
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