进度对话框不会关闭

Posted 2023-04-14

【中文标题】进度对话框不会关闭

【英文标题】：progress dialog does not dismiss

【发布时间】：2013-07-05 03:24:06

【问题描述】：

我要做的是在用户单击一个名为 location_Button 的按钮后获取用户的位置，然后显示一个显示有关其位置的一些信息的框。我试过这样：

Button location_Button=(Button) findViewById(R.id.location_button);
    location_Button.setOnClickListener(new View.OnClickListener() 
        @Override
        public void onClick(View view) 
            // Define a listener that responds to location updates
           progressDialog = ProgressDialog.show(Settings.this, "", "Loading...");

            final LocationListener locationListener = new LocationListener() 

                public void onLocationChanged(Location location) 
                    // Called when a new location is found by the network location provider.

                    lat =location.getLatitude();
                    lon = location.getLongitude();
                    try

                        addresses=(geocoder.getFromLocation(lat, lon, 1));
                        if (addresses.size() > 0) 
                            String city = addresses.get(0).getAddressLine(1);
                            String id = city.substring(0,city.length()-5);
                            String state1=String.valueOf(id.charAt(id.length()-3));
                            String state2=String.valueOf(id.charAt(id.length()-2));
                            String STATE = state1+state2;

                            locationManager.removeUpdates(this);
                            progressDialog.dismiss();

                            //alert dialog is established and displayed here



                        
                        else 
                            //tv.setText("Oops...");
                        

                    catch(IOException e)
                        e.printStackTrace();
                    

                

                public void onStatusChanged(String provider, int status, Bundle extras) 

                public void onProviderEnabled(String provider) 

                public void onProviderDisabled(String provider) 
            ;

问题是进度对话框永远不会被关闭。按下按钮时没有进度对话框，它会搜索然后显示该框，而在进度对话框中，它会继续说正在加载并且永远不会被解雇。我的目标是在建立位置后关闭进度对话框，并且应该弹出警报对话框，但不是。进度对话框的位置不正确吗？

【参考方案1】：

正因为 android 总是异步的，你必须使用线程来使用进度对话框。一个例子：

在你的代码中，当你想启动对话框时，调用一个异步类：

Button location_Button=(Button) findViewById(R.id.location_button);
    location_Button.setOnClickListener(new View.OnClickListener() 
        @Override
        public void onClick(View view) 
            LocationChanged locationChanged = new LocationChanged(MainActivity.this, "Loading...");
            locationChanged.execute();
        

现在您需要创建 LocationChanged.java：

import android.app.ProgressDialog;
import android.content.Context;
import android.os.AsyncTask;

public class LocationChanged extends AsyncTask<Void, Void, Void> 

    private ProgressDialog progressDialog;
    private Context context;
        private String message;

    public LocationChanged (Context context, String message) 
        this.context = context;
                this.message = message;
        

    @Override
    protected void onPreExecute() 
        super.onPreExecute();
        progressDialog = ProgressDialog.show (context, null, message);
    

    @Override
    protected Void doInBackground( Void... params ) 
            // Here you add your code. 

            return null;
    

    @Override
    protected void onPostExecute( Void result ) 
        super.onPostExecute (result);

        progressDialog.dismiss();

          // You can add code to be executed after the progress (may be a result).
    

【讨论】：

好的，但我不确定在哪里放置 'final LocationManager locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE); geocoder = new Geocoder(this, Locale.getDefault());'