我使用单独的线程从url获取json对象。但问题是我想在获得结果时显示进度对话框。我创建了一个进度对话框，并在线程执行之前和之后调用show和dismiss。但是没有显示进度对话框。 这是我调用线程的方式。
private void getRecordsByCount(final String data) {
try {
// btnSelectall.setText(" ");
int color=Color.BLACK;
showProgressDialog();
tableLayoutGrid.removeAllViews();
final String[] details = data.split("_");
SimpleDateFormat df = new SimpleDateFormat("MM/dd/yyyy");
String formattedDate = df.format(new Date());
String url = ipaddress + "/GrantLeavesList?Companyid=" + user_info.get("CompanyId") + "&divisionid=" + details[3] + "&userid=" + user_info.get("userid") + "&roleid="
+ user_info.get("RoleId") + "&Employeeid=" + user_info.get("EmployeeId") + "&leavetypeid=" + staticDetails.get(details[0]) + "&strStatus=" + staticDetails.get(details[1])
+ "&type=" + staticDetails.get(details[2]) + "&Date=" + formattedDate;
JsonThread thread = new JsonThread(url);
thread.start();
// thread.setPriority(Thread.MAX_PRIORITY);
thread.join();
JSONObject obj = thread.returnResult();
btnGrantSubmit.setVisibility(View.GONE);
if (obj != null) {
leaveforwardcounts = obj.getJSONArray("Table1");
ScrollView scrollGrid = new ScrollView(this);
TableRow datarow = new TableRow(this);
datarow.setWeightSum(100);
TableLayout table = new TableLayout(this);
for (int i = 0; i < leaveforwardcounts.length(); i++) {
btnGrantSubmit.setVisibility(View.VISIBLE);
JSONObject record = leaveforwardcounts.getJSONObject(i);
String applicantname = record.getString("Applicant");
String toDate = record.getString("ToDate");
String noofdays = record.getString("NumberOfDays");
String LOP = record.getString("LOP");
if(LOP!=null && LOP.trim().length()!=0)
{
color=Color.RED;
}
final int id = i;
final Button gridbutton = new Button(this);
gridbutton.setText(status);
gridbutton.setTextColor(Color.BLACK);
gridbutton.setBackgroundResource(R.drawable.grdbutton_30x30);
gridbutton.setGravity(Gravity.CENTER);
gridbutton.setPadding(2, 0, 2, 0);
gridbutton.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
changeRadioButtonState(gridbutton, id, data);
}
});
gridbutton.setOnLongClickListener(new OnLongClickListener() {
@Override
public boolean onLongClick(View v) {
setSelection(gridbutton);
return true;
}
});
TextView tvApplicantName = new TextView(this);
TextView tvToDate = new TextView(this);
TextView tvNoOfDays = new TextView(this);
TextView empty = new TextView(this);
TextView empty2 = new TextView(this);
if (applicantname.trim().length() >= 18) {
applicantname = applicantname.substring(0, 18);
}
tvApplicantName.setText(applicantname);
tvApplicantName.setTypeface(font2);
tvApplicantName.setWidth(70);
tvApplicantName.setTextColor(color);
tvApplicantName.setPadding(5, 0, 0, 0);
tvToDate.setText(toDate);
tvToDate.setTypeface(font2);
tvNoOfDays.setText(noofdays);
tvNoOfDays.setTypeface(font2);
tvNoOfDays.setGravity(Gravity.RIGHT);
Button ivDetails = new Button(this);
ivDetails.setText(" ");
ivDetails.setPadding(2, 0, 2, 0);
ivDetails.setBackgroundResource(R.drawable.detailsbutton_30x30);
ivDetails.setGravity(Gravity.CENTER);
ivDetails.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
leaveDetails = new PopupWindow(showLeaveDetails(id, leaveforwardcounts,data), (int) (width * 0.8), height / 2, true);
leaveDetails.showAtLocation(mainlayout, Gravity.CENTER, 0, 0);
}
});
TableRow row = new TableRow(this);
row.setPadding(0, 3, 0, 3);
row.setWeightSum(100);
row.addView(tvApplicantName, new TableRow.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT, 55));
row.addView(tvNoOfDays, new TableRow.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT, 5));
row.addView(empty2, new TableRow.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT, 20));
row.addView(ivDetails, new TableRow.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT, 5));
row.addView(empty, new TableRow.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT, 5));
row.addView(gridbutton, new TableRow.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT, 5));
table.addView(row);
}
scrollGrid.addView(table);
datarow.addView(scrollGrid, new TableRow.LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT, 100));
tableLayoutGrid.addView(datarow);
dialog.dismiss();
}
} catch (Exception e) {
e.printStackTrace();
}
}
package com.MobJax.dashboard;
import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import org.apache.http.util.ByteArrayBuffer;
import org.json.JSONObject;
public class JsonThread extends Thread{
boolean running=false;
String url;
JSONObject jobj=null;
public JsonThread(String url)
{
this.url=url;
}
@Override
public void run() {
int k=0;
URL url1;
try {
url1 = new URL(url);
InputStream input=url1.openStream();
BufferedInputStream bis=new BufferedInputStream(input);
ByteArrayBuffer baf=new ByteArrayBuffer(1000);
while((k=bis.read())!=-1)
{
baf.append((byte)k);
}
String results=new String(baf.toByteArray());
jobj=new JSONObject(results);
}
catch (MalformedURLException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
catch(Exception e)
{
e.printStackTrace();
}
}
public JSONObject returnResult()
{
return jobj;
}
}
答案 0 :(得分：5)
您可以使用AsyncTask来完成此操作。将线程部分添加到doInBackground方法中...显示onPreExecute中的进度对话框并在onPostExecute中将其关闭..
例如：
public class MyTask extends AsyncTask<String, Void, String> {
private Context context;
private ProgressDialog progressDialog;
public MyTask (Context context) {
this.context = context;
}
@Override
protected void onPreExecute() {
progressDialog = ProgressDialog.show(context, "", "Loading...", true);
}
/*
* @see android.os.AsyncTask#doInBackground(Params[])
*/
@Override
protected String doInBackground(String... arg0) {
//your json thread part
}
@Override
protected void onPostExecute(final String result) {
progressDialog.dismiss();
}
}
答案 1 :(得分：0)
不要自己创建和处理单独的线程，而是使用Asynctask。它会让你的工作更轻松。您可以在执行此异步任务时显示进度对话框，并且可以使用publishProgress（）
从asynctask更新进度对话框