1.由于需要删除文件，因此需要如下权限：
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>
2.核心代码
[java]
view plain
copy
1. package com.example.deleteyoumi;
2.
3. import java.io.File;
4.
5. import android.os.Bundle;
6. import android.os.Handler;
7. import android.os.Message;
8. import android.app.Activity;
9. import android.view.Menu;
10. import android.view.View;
11. import android.view.View.OnClickListener;
12. import android.widget.Button;
13. import android.widget.Toast;
14. /*
15. *@author: ZhengHaibo
16. *web:
18. *2013-4-28 Nanjing,njupt,China
19. */
20. public class DeleteYouMiMainActivity extends Activity implements
21. OnClickListener {
22. private Button deleteButton;
23. private final static String youmiPathString = "/mnt/sdcard/Android/data/.youmicache/";//文件夹的路径
24.
25. @Override
26. protected void onCreate(Bundle savedInstanceState) {
27. super.onCreate(savedInstanceState);
28. setContentView(R.layout.activity_delete_you_mi_main);
29. deleteButton = (Button) findViewById(R.id.delete_youmi);
30. this);
31. }
32.
33. @Override
34. public boolean onCreateOptionsMenu(Menu menu) {
35. // Inflate the menu; this adds items to the action bar if it is present.
36. getMenuInflater().inflate(R.menu.delete_you_mi_main, menu);
37. return true;
38. }
39.
40. @Override
41. public void onClick(View v) {
42. // TODO Auto-generated method stub
43. switch (v.getId()) {
44. case R.id.delete_youmi:
45. new File(youmiPathString);
46. DeleteFile(file);
47. 1);
48. break;
49. default:
50. break;
51. }
52. }
53. new Handler() {
54. public void handleMessage(Message msg) {
55. switch (msg.what) {
56. case 0:
57. "文件或文件夹不存在", Toast.LENGTH_LONG).show();
58. break;
59. case 1:
60. "删除成功！", Toast.LENGTH_LONG).show();
61. break;
62. default:
63. break;
64. }
65. };
66. };
67. /**
68. * 递归删除文件和文件夹
69. *
70. * @param file
71. * 要删除的根目录
72. */
73. public void DeleteFile(File file) {
74. if (file.exists() == false) {
75. 0);
76. return;
77. else {
78. if (file.isFile()) {
79. file.delete();
80. return;
81. }
82. if (file.isDirectory()) {
83. File[] childFile = file.listFiles();
84. if (childFile == null || childFile.length == 0) {
85. file.delete();
86. return;
87. }
88. for (File f : childFile) {
89. DeleteFile(f);
90. }
91. file.delete();
92. }
93. }
94. }
95. }
3.拓展
本博客是以删除为例。当然，对于遍历某文件夹下的所有文件均可用这个方法。如搜索.mp3文件等。
