Android在線更新 遠程安裝程序

第一步：使用java.net的URLConnection對象來創建連接

第二步：通過InputStream將下載的文件寫入存儲卡內緩存

第三步：下載完畢之後，通過自定義的openFile()方法打開文件，判斷文件類型，若為APK，開始安裝

第四步：准備離開Installer程序的同時，通過自制的delFile()方法，刪除緩存內文件

1. /**
2. * 遠程下載安裝Android程序
3. *
4. * @ClassName InstallOnlineActivity
5. * @author Jet
6. * @date 2012-9-14
7. */
8. public class InstallOnlineActivity extends Activity {
9. private TextView mTextView;
10. private EditText mEditText;
11. private Button mButton;
12. private String currentFilePath = "";
13. private String currentTempFilePath = "";
14. private String strURL = "";
15. private String fileEx = "";
16. private String fileName = "";
18. @Override
19. protected void onCreate(Bundle savedInstanceState) {
20. super.onCreate(savedInstanceState);
21. setContentView(R.layout.installonline);
22. mTextView = (TextView) findViewById(R.id.installonline_text1);
23. mEditText = (EditText) findViewById(R.id.installonline_edittext1);
24. mButton = (Button) findViewById(R.id.installonline_button1);
25. mButton.setOnClickListener(new OnClickListener() {
27. @Override
28. public void onClick(View v) {
29. // 將文件下載到本地
30. mTextView.setText("下載中...");
31. strURL = mEditText.getText().toString();
32. // 截取文件後綴
33. fileEx = strURL.substring(strURL.lastIndexOf('.') + 1,
34. strURL.length()).toLowerCase();
35. // 截取文件名
36. fileName = strURL.substring(strURL.lastIndexOf('/') + 1,
37. strURL.lastIndexOf('.'));
38. getFile(strURL);
39. }
41. });
42. }
44. private void getFile(final String strPath) {
45. if (currentFilePath.equals(strPath)) {
46. getDataSource(strPath);
47. }
48. currentFilePath = strPath;
49. Runnable r = new Runnable() {
51. @Override
52. public void run() {
53. getDataSource(strPath);
54. }
55. };
56. new Thread(r).start();
57. }
59. private void getDataSource(String url) {
60. if (!URLUtil.isNetworkUrl(url)) {
61. mTextView.setText("請填寫正確的URL");
62. } else {
63. try {
64. URL myUrl = new URL(url);
65. // 取得連接
66. URLConnection conn = myUrl.openConnection();
67. // 連接
68. conn.connect();
69. // 獲得輸入流
70. InputStream is = conn.getInputStream();
71. if (is == null) {
72. throw new RuntimeException("stream is null");
73. }
74. // 創建臨時文件
75. File myTempFile = File.createTempFile(fileName, "." + fileEx);
76. // 取得臨時文件存放路徑
77. currentTempFilePath = myTempFile.getAbsolutePath();
78. FileOutputStream fos = new FileOutputStream(myTempFile);
79. byte[] buf = new byte[128];
80. do {
81. // 返回現在所讀緩沖區的大小
82. int numread = is.read(buf);
83. if (numread <= 0) {
84. break;
85. }
86. fos.write(buf, 0, numread);
87. } while (true);
88. // 打開文件進行安裝
89. openFile(myTempFile);
90. is.close();
91. } catch (MalformedURLException e) {
92. e.printStackTrace();
93. } catch (IOException e) {
94. e.printStackTrace();
95. }
96. }
97. }
99. private void openFile(File file) {
100. Intent intent = new Intent();
101. intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
102. intent.setAction(android.content.Intent.ACTION_VIEW);
103. String type = getMimeType(file);
104. intent.setDataAndType(Uri.fromFile(file), type);
105. startActivity(intent);
106. }
108. private String getMimeType(File file) {
109. String type = "";
110. String fname = file.getName();
111. // 獲得擴展名
112. String end = fname
113. .substring(fname.lastIndexOf('.') + 1, fname.length())
114. .toLowerCase();
115. // 按擴展名的類型決定MimeType
116. if ("m4a".equals(end) || "mp3".equals(end) || "mid".equals(end)
117. || "xmf".equals(end) || "ogg".equals(end) || "wav".equals(end)) {
118. type = "audio";
119. } else if ("3gp".equals(end) || "mp4".equals(end)) {
120. type = "video";
121. } else if ("jpg".equals(end) || "gif".equals(end) || "png".equals(end)
122. || "jpeg".equals(end) || "bmp".equals(end)) {
123. type = "image";
124. } else if ("apk".equals(end)) {
125. type = "application/vnd.android.package-archive";
126. } else {
127. type = "*";
128. }
129. if ("apk".equals(end)) {
131. } else {
132. type += "/*";
133. }
134. return type;
135. }
136. private void delFile(String fileName){
137. File file = new File(fileName);
138. if(file.exists()){
139. file.delete();
140. }
141. }
142. @Override
143. protected void onPause() {
144. mTextView = (TextView) findViewById(R.id.installonline_text1);
145. mTextView.setText("下載成功");
146. super.onPause();
147. }
148. @Override
149. protected void onResume() {
150. //刪除臨時文件
151. delFile(currentTempFilePath);
152. super.onResume();
153. }
154. }