现在保存JSON外部存储器不工作 [英] saving json to external memory now not working
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问题描述
我认为这是工作，但现在它没有，只是想下载然后打开下载
四，增加了一些COE
公共类MainActivity延伸活动{字符串entityString = NULL;
串storyObj =;
JSON对象= NULL;
HttpEntity实体= NULL;
InputStream为= NULL;
整数responseInteger = NULL;//外部存储检查
布尔storageAvailable = FALSE;
布尔storageWriteable = FALSE;
字符串状态= Environment.getExternalStorageState（）;@覆盖
公共无效的onCreate（捆绑savedInstanceState）{
super.onCreate（savedInstanceState）;
的setContentView（R.layout.main）; 按钮downloadBtn =（按钮）findViewById（R.id.downloadButton）;
downloadBtn.setOnClickListener（新View.OnClickListener（）{ @覆盖
公共无效的onClick（视图v）{ saveToExternal（）; }
}）; 按钮loadBtn =（按钮）findViewById（R.id.loadButton）;
loadBtn.setOnClickListener（新View.OnClickListener（）{ @覆盖
公共无效的onClick（视图v）{ loadExternal（）; }
}）;
//的onCreate结束（）
}
公共无效saveToExternal（）{
TextView的测试=（的TextView）findViewById（R.id.textView）;
尝试{
//连接到MySQL
HttpClient的客户端=新DefaultHttpClient（）;
HttpPost后=新HttpPost（http://10.0.2.2/textures_story_list.php）;
HTT presponse响应= client.execute（岗位）;
//捕获响应
实体= response.getEntity（）;
InputStream的entityStream = entity.getContent（）;
StringBuilder的entityStringBuilder =新的StringBuilder（）;
字节[]缓冲区=新的字节[1024];
INT bytesReadCount;
而（（bytesReadCount = entityStream.read（缓冲液））大于0）{
entityStringBuilder.append（新的String（缓冲，0，bytesReadCount））;
}
entityString = entityStringBuilder.toString（）;
// responseInteger = Integer.valueOf（entityString）;
}赶上（例外五）{
Log.e（log_tag，在HTTP连接错误+ e.toString（））;
} //写为String从entityString外部存储器 //首先检查存储状态
尝试{ 如果（Environment.MEDIA_MOUNTED.equals（州））{
storageAvailable = storageWriteable = TRUE;
}否则如果（Environment.MEDIA_MOUNTED_READ_ONLY.equals（州））{
storageAvailable = TRUE;
storageWriteable = FALSE;
}其他storageAvailable = storageWriteable = FALSE;
如果（storageAvailable＆安培;＆安培; storageWriteable）{
文件extFile =新的文件（Environment.getExternalStorageDirectory（），/android/data/com.game/story.json）;
FileOutputStream中出=新的FileOutputStream（extFile）; out.write（entityString.getBytes（））;
了out.flush（）;
out.close（）;
}
}赶上（例外五）{
Log.e（log_tag，错误保存字符串+ e.toString（））;
}// saveJson结束（）
}公共无效loadExternal（）{
TextView的测试=（的TextView）findViewById（R.id.textView）; //加载文件
尝试{ 的FileInputStream的FileInput = openFileInput（/安卓/数据/ com.game / story.json）; 的BufferedReader inputReader =新的BufferedReader（新的InputStreamReader（的FileInput，UTF-8），8）;
StringBuilder的strBuilder =新的StringBuilder（）;
串线= NULL;
而（（行= inputReader.readLine（））！= NULL）{
strBuilder.append（行+\\ n）;
}
fileInput.close（）;
storyObj = strBuilder.toString（）; }赶上（IOException异常五）{
Log.e（log_tag，错误建筑物字符串+ e.toString（））;
} 尝试{
JSONArray jArray =新JSONArray（storyObj）;
串storyNames =;
的for（int i = 0; I＆LT; jArray.length（）;我++）{
storyNames + = jArray.getJSONObject（ⅰ）.getString（story_name）+\\ N的;
}
test.setText（storyNames）; }赶上（JSONException E）{
Log.e（log_tag，错误返回字符串+ e.toString（））;
}
返回;
//和openJson的（）
}
//类体结束
}
错误说，它没有文件story.json没有人知道codeS IM缺少解决这一问题？现在我的错误是
错误节省字符串java.io.FileNotFoundException：/mnt/sdcard/android/data/com.game/story.json（没有这样的文件或目录）
解决方案
类似的东西：
..........
字符串内容= loadFromHttp（）;
savedToExternal（内容，story.json）;
字符串资源= loadFromExternal（story.json）;
..........
私人无效savedToExternal（字符串内容，字符串文件名）{
FOS的FileOutputStream = NULL;
作家出= NULL;
尝试{
档案文件=新的文件（getAppRootDir（），文件名）;
FOS =新的FileOutputStream（文件）;
OUT =新OutputStreamWriter（FOS，UTF-8）; out.write（内容）;
了out.flush（）;
}赶上（Throwable的E）{
e.printStackTrace（）;
} {最后
如果（FOS！= NULL）{
尝试{
fos.close（）;
}赶上（IOException异常忽略）{}
}
如果（满分！= NULL）{
尝试{
out.close（）;
}赶上（IOException异常忽略）{}
}
}
}私人字符串loadFromExternal（字符串文件名）{
字符串资源= NULL;
档案文件=新的文件（getAppRootDir（），文件名）;
如果（！file.exists（））{
Log.e（，文件+ file.getAbsolutePath（）+找不到）;
返回null;
}
FIS的FileInputStream = NULL;
BufferedReader中inputReader = NULL;
尝试{
FIS =新的FileInputStream（文件）;
inputReader =新的BufferedReader（新的InputStreamReader（FIS，UTF-8））;
StringBuilder的strBuilder =新的StringBuilder（）;
串线;
而（（行= inputReader.readLine（））！= NULL）{
strBuilder.append（行+\\ n）;
}
RES = strBuilder.toString（）;
}赶上（Throwable的E）{
如果（FIS！= NULL）{
尝试{
fis.close（）;
}赶上（IOException异常忽略）{}
}
如果（inputReader！= NULL）{
尝试{
inputReader.close（）;
}赶上（IOException异常忽略）{}
}
}
返回水库;
}公共文件getAppRootDir（）{
文件appRootDir;
布尔externalStorageAvailable;
布尔externalStorageWriteable;
字符串状态= Environment.getExternalStorageState（）;
如果（Environment.MEDIA_MOUNTED.equals（州））{
externalStorageAvailable = externalStorageWriteable = TRUE;
}否则如果（Environment.MEDIA_MOUNTED_READ_ONLY.equals（州））{
externalStorageAvailable = TRUE;
externalStorageWriteable = FALSE;
}其他{
externalStorageAvailable = externalStorageWriteable = FALSE;
}
如果（externalStorageAvailable＆安培;＆安培; externalStorageWriteable）{
appRootDir = getExternalFilesDir（NULL）;
}其他{
appRootDir = GETDIR（appRootDir，MODE_PRIVATE）;
}
如果（！appRootDir.exists（））{
appRootDir.mkdir（）;
}
返回appRootDir;
}
............
i thought this was working but now its not, just suppose to download then open the download iv added some coe
public class MainActivity extends Activity {
String entityString = null;
String storyObj = "";
Object json = null;
HttpEntity entity = null;
InputStream is = null;
Integer responseInteger = null;
//external storage check
boolean storageAvailable = false;
boolean storageWriteable = false;
String state = Environment.getExternalStorageState();
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button downloadBtn = (Button) findViewById(R.id.downloadButton);
downloadBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
saveToExternal();
}
});
Button loadBtn = (Button) findViewById(R.id.loadButton);
loadBtn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
loadExternal();
}
});
//end of onCreate()
}
public void saveToExternal(){
TextView test = (TextView) findViewById(R.id.textView);
try{
//connects to mySQL
HttpClient client = new DefaultHttpClient();
HttpPost post = new HttpPost("http://10.0.2.2/textures_story_list.php");
HttpResponse response = client.execute(post);
//captures the response
entity = response.getEntity();
InputStream entityStream = entity.getContent();
StringBuilder entityStringBuilder = new StringBuilder();
byte [] buffer = new byte[1024];
int bytesReadCount;
while ((bytesReadCount = entityStream.read(buffer)) > 0) {
entityStringBuilder.append(new String(buffer, 0, bytesReadCount));
}
entityString = entityStringBuilder.toString();
//responseInteger = Integer.valueOf(entityString);
}catch(Exception e) {
Log.e("log_tag", "Error in http connection "+e.toString());
}
//writes as String from entityString to external memory
//first check storage state
try{
if (Environment.MEDIA_MOUNTED.equals(state)){
storageAvailable = storageWriteable = true;
} else if (Environment.MEDIA_MOUNTED_READ_ONLY.equals(state)){
storageAvailable = true;
storageWriteable = false;
} else storageAvailable = storageWriteable = false;
if(storageAvailable && storageWriteable) {
File extFile = new File(Environment.getExternalStorageDirectory(), "/android/data/com.game/story.json");
FileOutputStream out = new FileOutputStream(extFile);
out.write(entityString.getBytes());
out.flush();
out.close();
}
}catch(Exception e) {
Log.e("log_tag", "Error saving string "+e.toString());
}
//end of saveJson()
}
public void loadExternal(){
TextView test = (TextView) findViewById(R.id.textView);
//loads the files
try{
FileInputStream fileInput = openFileInput("/android/data/com.game/story.json");
BufferedReader inputReader = new BufferedReader(new InputStreamReader(fileInput, "UTF-8"), 8);
StringBuilder strBuilder = new StringBuilder();
String line = null;
while ((line = inputReader.readLine()) != null) {
strBuilder.append(line + "\n");
}
fileInput.close();
storyObj = strBuilder.toString();
}catch(IOException e){
Log.e("log_tag", "Error building string "+e.toString());
}
try{
JSONArray jArray = new JSONArray(storyObj);
String storyNames = "";
for(int i = 0;i<jArray.length();i++){
storyNames += jArray.getJSONObject(i).getString("story_name") +"\n";
}
test.setText(storyNames);
}catch(JSONException e) {
Log.e("log_tag", "Error returning string "+e.toString());
}
return;
//and of openJson()
}
//end of class body
}
the error says it has no file story.json does anyone know what codes im missing to fix this? my error is now
Error saving string java.io.FileNotFoundException: /mnt/sdcard/android/data/com.game/story.json (No such file or directory)
解决方案
Something like that:
..........
String content = loadFromHttp();
savedToExternal(content, "story.json");
String res = loadFromExternal("story.json");
..........
private void savedToExternal(String content, String fileName) {
FileOutputStream fos = null;
Writer out = null;
try {
File file = new File(getAppRootDir(), fileName);
fos = new FileOutputStream(file);
out = new OutputStreamWriter(fos, "UTF-8");
out.write(content);
out.flush();
} catch (Throwable e){
e.printStackTrace();
} finally {
if(fos!=null){
try {
fos.close();
} catch (IOException ignored) {}
}
if(out!= null){
try {
out.close();
} catch (IOException ignored) {}
}
}
}
private String loadFromExternal(String fileName) {
String res = null;
File file = new File(getAppRootDir(), fileName);
if(!file.exists()){
Log.e("", "file " +file.getAbsolutePath()+ " not found");
return null;
}
FileInputStream fis = null;
BufferedReader inputReader = null;
try {
fis = new FileInputStream(file);
inputReader = new BufferedReader(new InputStreamReader(fis, "UTF-8"));
StringBuilder strBuilder = new StringBuilder();
String line;
while ((line = inputReader.readLine()) != null) {
strBuilder.append(line + "\n");
}
res = strBuilder.toString();
} catch(Throwable e){
if(fis!=null){
try {
fis.close();
} catch (IOException ignored) {}
}
if(inputReader!= null){
try {
inputReader.close();
} catch (IOException ignored) {}
}
}
return res;
}
public File getAppRootDir() {
File appRootDir;
boolean externalStorageAvailable;
boolean externalStorageWriteable;
String state = Environment.getExternalStorageState();
if (Environment.MEDIA_MOUNTED.equals(state)) {
externalStorageAvailable = externalStorageWriteable = true;
} else if (Environment.MEDIA_MOUNTED_READ_ONLY.equals(state)) {
externalStorageAvailable = true;
externalStorageWriteable = false;
} else {
externalStorageAvailable = externalStorageWriteable = false;
}
if (externalStorageAvailable && externalStorageWriteable) {
appRootDir = getExternalFilesDir(null);
} else {
appRootDir = getDir("appRootDir", MODE_PRIVATE);
}
if (!appRootDir.exists()) {
appRootDir.mkdir();
}
return appRootDir;
}
............
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