Java Android:JsonWriter无法写入文件
我试图在收到wifi信息后调用Java Android:JsonWriter无法写入文件,java,android,json,writer,Java,Android,Json,Writer,我试图在收到wifi信息后调用JsonWriter方法向test.json添加一些内容,但在成功写入文件后,文件仍然为空。下面是代码 OnReceive @Override public void onReceive(Context c, Intent i) { if (i.getAction().equals(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION)) {
JsonWriter
方法向test.json添加一些内容,但在成功写入文件后,文件仍然为空。下面是代码
OnReceive
@Override
public void onReceive(Context c, Intent i) {
if (i.getAction().equals(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION))
{
dbhelp = new DataBaseHelper(c);
wifilist = new ArrayList<ScanResult>();
wifilist = ((WifiManager) c.getSystemService(Context.WIFI_SERVICE)).getScanResults();
dialog.dismiss();
file = new File(c.getExternalCacheDir(),"testJson.json");
try
{
out = new FileOutputStream(file);
writeJson(out);
}
catch(IOException e)
{
e.printStackTrace();
}
}
}
{
"status": "OK",
"num_results": "",
}
预期结果应该是
@Override
public void onReceive(Context c, Intent i) {
if (i.getAction().equals(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION))
{
dbhelp = new DataBaseHelper(c);
wifilist = new ArrayList<ScanResult>();
wifilist = ((WifiManager) c.getSystemService(Context.WIFI_SERVICE)).getScanResults();
dialog.dismiss();
file = new File(c.getExternalCacheDir(),"testJson.json");
try
{
out = new FileOutputStream(file);
writeJson(out);
}
catch(IOException e)
{
e.printStackTrace();
}
}
}
{
"status": "OK",
"num_results": "",
}
忘记调用
JsonWriter.close()代码>在编写JSONObject
之后,按照以下步骤进行操作:
writer.name("status").value("OK");
writer.name("num_results").value("");
writer.endObject();
writer.close(); //<<< call close here
writer.name(“status”).value(“OK”);
writer.name(“num_results”).value(“”);
writer.endObject();
writer.close()// 忘记调用JsonWriter.close()代码>在编写JSONObject
之后,按照以下步骤进行操作:
writer.name("status").value("OK");
writer.name("num_results").value("");
writer.endObject();
writer.close(); //<<< call close here
writer.name(“status”).value(“OK”);
writer.name(“num_results”).value(“”);
writer.endObject();
writer.close()//如果我想在服务器上执行或调用外部文件。若我想在服务器上执行或调用一个外部文件,我该怎么做呢。我怎么做?