Android 下載文件 進度條顯示

加入兩個權限

一個是聯網，另一個是讀寫SD卡

1. <uses-permission Android:name="android.permission.INTERNET"></uses-permission>
2. <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>

下載地址是本人的另外一台主機，現在當服務器了，路徑可以測試

http://210.30.12.1:8080/mp3/DJ.mp3

1. import java.io.File;
2. import java.io.FileNotFoundException;
3. import java.io.FileOutputStream;
4. import java.io.IOException;
5. import java.io.InputStream;
6. import java.io.OutputStream;
7. import java.io.RandomAccessFile;
8. import java.net.MalformedURLException;
9. import java.net.URL;
10. import java.net.URLConnection;
12. import android.app.Activity;
13. import android.os.Bundle;
14. import android.os.Environment;
15. import android.os.Handler;
16. import android.os.Message;
17. import android.util.Log;
18. import android.view.View;
19. import android.view.View.OnClickListener;
20. import android.widget.Button;
21. import android.widget.ProgressBar;
22. import android.widget.TextView;
23. import android.widget.Toast;
25. public class FileDownProcessBarActivity extends Activity {
26. /** Called when the activity is first created. */
27. private static final String Path="http://210.30.12.1:8080/mp3/DJ.mp3";
28. private ProgressBar progressBar;
29. private TextView textView;
30. private Button button;
31. private int FileLength;
32. private int DownedFileLength=0;
33. private InputStream inputStream;
34. private URLConnection connection;
35. private OutputStream outputStream;
36. @Override
37. public void onCreate(Bundle savedInstanceState) {
38. super.onCreate(savedInstanceState);
39. setContentView(R.layout.main);
40. progressBar=(ProgressBar) findViewById(R.id.progressBar1);
41. textView=(TextView) findViewById(R.id.textView2);
42. button=(Button) findViewById(R.id.button1);
43. button.setOnClickListener(new ButtonListener());
44. }
45. class ButtonListener implements OnClickListener{
47. @Override
48. public void onClick(View v) {
49. DownedFileLength=0;
50. // TODO Auto-generated method stub
51. Thread thread=new Thread(){
52. public void run(){
53. try {
54. DownFile(Path);
55. } catch (Exception e) {
56. // TODO: handle exception
57. }
58. }
59. };
60. thread.start();
61. }
62. }
63. private Handler handler=new Handler()
64. {
65. public void handleMessage(Message msg)
66. {
67. if (!Thread.currentThread().isInterrupted()) {
68. switch (msg.what) {
69. case 0:
70. progressBar.setMax(FileLength);
71. Log.i("文件長度----------->", progressBar.getMax()+"");
72. break;
73. case 1:
74. progressBar.setProgress(DownedFileLength);
75. int x=DownedFileLength*100/FileLength;
76. textView.setText(x+"%");
77. break;
78. case 2:
79. Toast.makeText(getApplicationContext(), "下載完成", Toast.LENGTH_LONG).show();
80. break;
82. default:
83. break;
84. }
85. }
86. }
88. };
90. private void DownFile(String urlString)
91. {
93. /*
94. * 連接到服務器
95. */
97. try {
98. URL url=new URL(urlString);
99. connection=url.openConnection();
100. if (connection.getReadTimeout()==5) {
101. Log.i("---------->", "當前網絡有問題");
102. // return;
103. }
104. inputStream=connection.getInputStream();
106. } catch (MalformedURLException e1) {
107. // TODO Auto-generated catch block
108. e1.printStackTrace();
109. } catch (IOException e) {
110. // TODO Auto-generated catch block
111. e.printStackTrace();
112. }
114. /*
115. * 文件的保存路徑和和文件名其中Nobody.mp3是在手機SD卡上要保存的路徑，如果不存在則新建
116. */
117. String savePAth=Environment.getExternalStorageDirectory()+"/DownFile";
118. File file1=new File(savePAth);
119. if (!file1.exists()) {
120. file1.mkdir();
121. }
122. String savePathString=Environment.getExternalStorageDirectory()+"/DownFile/"+"DJ.mp3";
123. File file =new File(savePathString);
124. if (!file.exists()) {
125. try {
126. file.createNewFile();
127. } catch (IOException e) {
128. // TODO Auto-generated catch block
129. e.printStackTrace();
130. }
131. }
132. /*
133. * 向SD卡中寫入文件,用Handle傳遞線程
134. */
135. Message message=new Message();
136. try {
137. outputStream=new FileOutputStream(file);
138. byte [] buffer=new byte[1024*4];
139. FileLength=connection.getContentLength();
140. message.what=0;
141. handler.sendMessage(message);
142. while (DownedFileLength<FileLength) {
143. outputStream.write(buffer);
144. DownedFileLength+=inputStream.read(buffer);
145. Log.i("-------->", DownedFileLength+"");
146. Message message1=new Message();
147. message1.what=1;
148. handler.sendMessage(message1);
149. }
150. Message message2=new Message();
151. message2.what=2;
152. handler.sendMessage(message2);
153. } catch (FileNotFoundException e) {
154. // TODO Auto-generated catch block
155. e.printStackTrace();
156. } catch (IOException e) {
157. // TODO Auto-generated catch block
158. e.printStackTrace();
159. }
160. }
162. }