【发布时间】:2014-02-13 02:05:46
【问题描述】:
所以目前我有一个 AsyncTask 类,当我单击一个按钮时,它运行并将数据 POST 到我的服务器(效果很好)。
我现在要做的是处理用户未连接到互联网时发生的事情。所以我设置了这些类来在互联网连接时通知应用程序,以便数据可以自动发送到服务器。
AsyncTask 类(内部类)
private class HttpAsyncTask extends AsyncTask<String, Void, String> {
ProgressDialog dialog = new ProgressDialog(getActivity());
final AlertDialog finishedDialog = new AlertDialog.Builder(getActivity())
.setCancelable(false)
.setPositiveButton(android.R.string.ok, null)
.create();
@Override
protected String doInBackground(String... urls) {
onProgressUpdate("Uploading Data...");
return POST(urls[0]);
}
@Override
protected void onPreExecute() {
this.dialog.show();
finishedDialog.setOnShowListener(new DialogInterface.OnShowListener(){
@Override
public void onShow(DialogInterface dialog) {
Button b = finishedDialog.getButton(AlertDialog.BUTTON_POSITIVE);
b.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
// navigate to match summary.....
finishedDialog.dismiss();
}
});
}
});
}
protected void onProgressUpdate(String msg) {
dialog.setMessage(msg);
}
// onPostExecute displays the results of the AsyncTask.
@Override
protected void onPostExecute(String result) {
if (result != ""){
finishedDialog.setTitle("Upload Complete!");
finishedDialog.setMessage("Data Sent Successfully");
finishedDialog.show();
dialog.dismiss();
editor.clear();
editor.commit();
//Toast.makeText(getActivity().getBaseContext(), result, Toast.LENGTH_LONG).show();
}else
{
Handler handler = new Handler();
handler.postDelayed(new Runnable() {
public void run() {
finishedDialog.setTitle("Upload Failed!");
finishedDialog.setMessage("Data Will Automatically Be Uploaded When Internet Connection Is Available");
finishedDialog.show();
dialog.dismiss();
}}, 1000);
setFlag(true);
}
}
}
public static boolean getFlag() {
return flag;
}
public void setFlag(boolean flag) {
this.flag = flag;
}
public String POST(String url){
InputStream inputStream = null;
String result = "";
try {
// 1. create HttpClient
HttpClient httpclient = new DefaultHttpClient();
// 2. make POST request to the given URL
HttpPost httpPost = new HttpPost(url);
if(adapter.updateNeeded()){
JSONObject main = new JSONObject(exmaplePrefs.getString("jsonString", "cant find json"));
JSONObject dbUpdates = new JSONObject(exmaplePrefs.getString("ChangesJSON", "cant find Changejson"));
main.put("Team_Updates", dbUpdates);
json = main.toString();
}else{
json = exmaplePrefs.getString("jsonString", "cant find json");
// String json = "{\"twitter\":\"test\",\"country\":\"test\",\"name\":\"test\"}";
}
// 5. set json to StringEntity
StringEntity se = new StringEntity(json);
se.setContentType("application/json;charset=UTF-8");
// 6. set httpPost Entity
httpPost.setEntity(se);
// 7. Set some headers to inform server about the type of the content
// httpPost.setHeader("Accept", "application/json");
// httpPost.setHeader("Content-type", "application/json");
// httpPost.setHeader("json", json);
// 8. Execute POST request to the given URL
HttpResponse httpResponse = httpclient.execute(httpPost);
// 9. receive response as inputStream
inputStream = httpResponse.getEntity().getContent();
String status = httpResponse.getStatusLine().toString();
// 10. convert inputstream to string
if (!status.equals("HTTP/1.1 500 Internal Server Error")){
if(inputStream != null){
result = convertInputStreamToString(inputStream);
}
else{
result = "Did not work!";
}
}else{
System.out.println("500 Error");
}
} catch (Exception e) {
Log.d("InputStream", e.getLocalizedMessage());
System.out.println("eerroorr "+e);
}
// 11. return result
System.out.println(result);
return result;
}
private static String convertInputStreamToString(InputStream inputStream) throws IOException{
BufferedReader bufferedReader = new BufferedReader( new InputStreamReader(inputStream));
String line = "";
String result = "";
while((line = bufferedReader.readLine()) != null)
result += line;
inputStream.close();
return result;
}
}
NetworkUtil 类
public class NetworkUtil {
public static int TYPE_WIFI = 1;
public static int TYPE_MOBILE = 2;
public static int TYPE_NOT_CONNECTED = 0;
public static int getConnectivityStatus(Context context) {
ConnectivityManager cm = (ConnectivityManager) context
.getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNetwork = cm.getActiveNetworkInfo();
if (null != activeNetwork) {
if(activeNetwork.getType() == ConnectivityManager.TYPE_WIFI)
return TYPE_WIFI;
if(activeNetwork.getType() == ConnectivityManager.TYPE_MOBILE)
return TYPE_MOBILE;
}
return TYPE_NOT_CONNECTED;
}
public static String getConnectivityStatusString(Context context) {
int conn = NetworkUtil.getConnectivityStatus(context);
String status = null;
if (conn == NetworkUtil.TYPE_WIFI) {
status = "Wifi enabled";
} else if (conn == NetworkUtil.TYPE_MOBILE) {
status = "Mobile data enabled";
} else if (conn == NetworkUtil.TYPE_NOT_CONNECTED) {
status = "Not connected to Internet";
}
return status;
}
}
BroadcastReceiver 类
public class NetworkChangeReceiver extends BroadcastReceiver {
@Override
public void onReceive(final Context context, final Intent intent) {
intent.getExtras();
String status = NetworkUtil.getConnectivityStatusString(context);
Toast.makeText(context, status, Toast.LENGTH_LONG).show();
if(MatchFragment.getFlag()){
//send data
}
}
}
所以在 BroadcastReceiver 类中,当应用程序尝试发送数据但没有互联网时,我检查设置为 true 的标志(AsyncTask 类中的 onPostExecute)。
所以想要做的是一些如何调用 POST 方法。我必须创建一个新的异步任务类吗?我在这里有点难过。
谢谢
【问题讨论】:
标签: java android android-asynctask broadcastreceiver