1     /**
 2      * SharedPreferences保存
 3      * @param v
 4      */
 5     public void sharedSave(View v){
 6         String name=etName.getText().toString().trim();
 7         String age=etAge.getText().toString().trim();
 8         if(TextUtils.isEmpty(name)||TextUtils.isEmpty(age)){
 9             return;
10         }
11         //构造一个编辑器----笔
12         SharedPreferences.Editor editor = sp.edit();
13         //数据的存储---只能存储简单的数据
14         editor.putString("name",name);
15         editor.putString("age",age);
16         //提交--保存
17         editor.commit();
18         //清空
19         etName.setText("");
20         etAge.setText("");
21     }
22
23     /**
24      * SharedPreferences读取
25      */
26     public void sharedRedo(View v){
27         String name=sp.getString("name","");
28         String age=sp.getString("age","");
29         etName.setText(name);
30         etAge.setText(age);
31     }

 1     /**
 2      * 内部保存
 3      * @param v
 4      */
 5     public void internalSave(View v) {
 6         String name = etName.getText().toString().trim();
 7         String age = etAge.getText().toString().trim();
 8         if (TextUtils.isEmpty(name) || TextUtils.isEmpty(age)) {
 9             return;
10         }
11
12         try {
13             String content = "这是我的姓名：" + name + "这是我的年龄：" + age;
14             FileOutputStream fos = openFileOutput(sname, MODE_PRIVATE);
15             fos.write(content.getBytes());
16             fos.close();
17             etName.setText("");
18             etAge.setText("");
19         } catch (IOException e) {
20             e.printStackTrace();
21         }
22     }
23
24     /**
25      * 内部读取
26      * @param v
27      */
28     public void internalRedo(View v) {
29         try {
30             FileInputStream fis = openFileInput(sname);
31             byte[] buffer = new byte[fis.available()];
32             fis.read(buffer);
33             fis.close();
34             String content = new String(buffer);
35             Toast.makeText(this, content, Toast.LENGTH_SHORT).show();
36         } catch (IOException e) {
37             e.printStackTrace();
38         }
39     }
40
41     /**
42      * 删除文件
43      * @param v
44      */
45     public void internalDel(View v){
46         boolean del=deleteFile(sname);
47         if(del){
48             Toast.makeText(this, "删除成功", Toast.LENGTH_SHORT).show();
49         }else{
50             Toast.makeText(this, "删除失败", Toast.LENGTH_SHORT).show();
51         }
52     }

1   <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"  />
2     <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
3     <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS" />

 1     /**
 2      * 外部存储
 3      * @param v
 4      */
 5     public void externalSave(View v) {
 6
 7         try {
 8             Log.i(TAG, "externalSave: 开始");
 9             Bitmap img = BitmapFactory.decodeResource(getResources(), R.drawable.bg);
10             ByteArrayOutputStream bass = new ByteArrayOutputStream();
11             img.compress(Bitmap.CompressFormat.JPEG, 100, bass);
12             img.recycle();
13             Log.i(TAG, "externalSave: saveImg");
14             boolean saveOk = saveImg("dog.jpg", bass.toByteArray());
15             Log.i(TAG, "externalSave: saveImg:"+saveOk);
16             if (saveOk) {
17                 Toast.makeText(this, "保存成功", Toast.LENGTH_SHORT).show();
18             }
19             bass.close();
20             Log.i(TAG, "externalSave: 结束");
21         } catch (IOException e) {
22             e.printStackTrace();
23             Log.i(TAG, "externalSave: 异常"+e.getMessage());
24         }
25     }
26
27     /**
28      * 外部读取
29      * @param v
30      */
31     public void externalRedo(View v) {
32         if (!isMounted()) {
33             return;
34         }
35         try {
36             Bitmap img = readImg("dog.jpg");
37             iv01.setImageBitmap(img);
38         } catch (Exception e) {
39             e.printStackTrace();
40         }
41     }
42
43     private boolean saveImg(String fileName,byte[] data){
44         Log.i(TAG, "saveImg: 开始");
45         if(!isMounted()){
46             Log.i(TAG, "saveImg: 挂载失败");
47             return false;
48         }
49         Log.i(TAG, "saveImg: 路径："+storedPath);
50         File dir=new File(storedPath);
51         if(!dir.exists()){
52            boolean f= dir.mkdirs();
53             if(f){
54                 Log.i(TAG, "saveImg: 创建目录成功："+storedPath);
55             }else{
56                 Log.i(TAG, "saveImg: 创建目录失败："+storedPath);
57             }
58         }
59         Log.i(TAG, "saveImg: 判断路径：ok");
60         try {
61             File file=new File(storedPath,fileName);
62             if(file.exists()){
63                 Log.i(TAG, "saveImg: 判断文件：1");
64                 file.delete();
65             }
66             Log.i(TAG, "saveImg: 判断文件：2");
67             file.createNewFile();
68             Log.i(TAG, "saveImg: 判断文件：ok");
69             FileOutputStream fos=new FileOutputStream(file);
70             fos.write(data);
71             fos.close();
72             return true;
73         } catch (IOException e) {
74             e.printStackTrace();
75             Log.i(TAG, "saveImg: 异常："+e.getMessage());
76             return false;
77         }
78     }
79
80     public Bitmap readImg(String fileName){
81         if(!isMounted()){
82             return null;
83         }
84         File imgFile=new File(storedPath,fileName);
85         if(imgFile.exists()){
86             return BitmapFactory.decodeFile(imgFile.getAbsolutePath());
87         }
88         return null;
89     }
90
91     private  boolean isMounted(){
92         String state=Environment.getExternalStorageState();
93         return  state.equals(Environment.MEDIA_MOUNTED);
94     }