file chooser

app/build.gradle

@@ -55,5 +55,8 @@ dependencies {
     implementation 'com.github.PhilJay:MPAndroidChart:v3.1.0'
     implementation 'com.jakewharton.threetenabp:threetenabp:1.2.1'
     implementation 'org.greenrobot:eventbus:3.0.0'
+    implementation 'org.apache.poi:poi:3.12'
+ //   implementation 'org.apache.poi:poi-ooxml:3.12'
+    implementation 'com.fasterxml:aalto-xml:1.0.0'
 
 }

app/src/main/java/cc/pogoda/mobile/pogodacc/activity/ExportDataActivity.java

@@ -1,9 +1,12 @@
 package cc.pogoda.mobile.pogodacc.activity;
 
+import androidx.annotation.Nullable;
 import androidx.appcompat.app.AppCompatActivity;
 
 import android.content.Intent;
+import android.net.Uri;
 import android.os.Bundle;
+import android.os.FileUtils;
 import android.text.Editable;
 import android.view.View;
 import android.widget.ArrayAdapter;
@@ -90,9 +93,35 @@ public class ExportDataActivity extends AppCompatActivity {
     }
 
     public int getOutputFormat() {
+
+        String selected = outputFormat.getSelectedItem().toString();
+
+        switch (selected) {
+            case "CSV" : return 1;
+            case "MS Excel XLSX": return 2;
+        }
+
         return -1;
     }
 
+    @Override
+    protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
+
+        String s;
+
+        if (requestCode == 123 && resultCode == RESULT_OK) {
+            Uri uri = data.getData();
+
+            s = uri.getPath();
+
+            FileUtils.
+
+            System.out.println(s);
+        }
+
+        super.onActivityResult(requestCode, resultCode, data);
+    }
+
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);

app/src/main/java/cc/pogoda/mobile/pogodacc/activity/handler/ExportDataActStartButtonClickEvent.java

@@ -1,9 +1,12 @@
 package cc.pogoda.mobile.pogodacc.activity.handler;
 
+import android.content.Intent;
+import android.net.Uri;
 import android.view.View;
 
 import cc.pogoda.mobile.pogodacc.activity.ExportDataActivity;
 import cc.pogoda.mobile.pogodacc.dao.StationDataDao;
+import cc.pogoda.mobile.pogodacc.file.ExcelExport;
 import cc.pogoda.mobile.pogodacc.type.WeatherStation;
 import cc.pogoda.mobile.pogodacc.type.web.ListOfStationData;
 
@@ -15,6 +18,17 @@ public class ExportDataActStartButtonClickEvent implements View.OnClickListener{
         activity = act;
     }
 
+    public void openDirectory(Uri uriToLoad) {
+        // Choose a directory using the system's file picker.
+        Intent intent = new Intent(Intent.ACTION_OPEN_DOCUMENT_TREE);
+
+        // Optionally, specify a URI for the directory that should be opened in
+        // the system file picker when it loads.
+        //intent.putExtra(DocumentsContract.EXTRA_INITIAL_URI, uriToLoad);
+
+        activity.startActivityForResult(intent, 123);
+    }
+
     @Override
     public void onClick(View view) {
 
@@ -30,6 +44,16 @@ public class ExportDataActStartButtonClickEvent implements View.OnClickListener{
 
             ListOfStationData stationData = stationDataDao.getLastStationData(toExport.getSystemName(), timestampStart, timestampStop);
 
+            int format = activity.getOutputFormat();
+
+            openDirectory(null);
+
+            if (format == 2) {
+                ExcelExport.exportToExcel(stationData, toExport, activity.getApplicationContext());
+
+            }
+
+
         }
 
     }

app/src/main/java/cc/pogoda/mobile/pogodacc/dao/TrendDao.java

@@ -8,7 +8,6 @@ import cc.pogoda.mobile.pogodacc.web.TrendConsumer;
 import retrofit2.Response;
 
 public class TrendDao {
-    RestClientConfig restClient;
 
     Response<Trend> trend;
 
@@ -16,6 +15,8 @@ public class TrendDao {
 
     class Worker implements Runnable {
 
+        RestClientConfig restClient;
+
         @Override
         public void run() {
 
@@ -27,7 +28,7 @@ public class TrendDao {
                 trend = trendConsumer.getTrendForStation(station).execute();
             }
             catch (IOException e) {
-
+                e.printStackTrace();
             }
         }
     }
@@ -47,6 +48,9 @@ public class TrendDao {
         } catch (InterruptedException e) {
             e.printStackTrace();
         }
+        catch (NullPointerException e) {
+            e.printStackTrace();
+        }
 
         return out;
     }

app/src/main/java/cc/pogoda/mobile/pogodacc/file/ExcelExport.java

@@ -0,0 +1,75 @@
+package cc.pogoda.mobile.pogodacc.file;
+
+import android.content.Context;
+import android.content.Intent;
+import android.net.Uri;
+import android.provider.DocumentsContract;
+
+import org.apache.poi.hssf.usermodel.HSSFWorkbook;
+import org.apache.poi.ss.usermodel.Cell;
+import org.apache.poi.ss.usermodel.Row;
+import org.apache.poi.ss.usermodel.Sheet;
+import org.apache.poi.ss.usermodel.Workbook;
+
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileOutputStream;
+import java.io.IOException;
+
+import cc.pogoda.mobile.pogodacc.type.WeatherStation;
+import cc.pogoda.mobile.pogodacc.type.web.ListOfStationData;
+
+public class ExcelExport {
+
+
+    public static boolean exportToExcel(ListOfStationData data, WeatherStation station, Context context) {
+
+        Cell cell;
+
+        Workbook workbook = new HSSFWorkbook();
+
+        Sheet sheet = workbook.createSheet(station.getSystemName());
+
+        Row header = sheet.createRow(3);
+
+        cell = header.createCell(0);
+        cell.setCellValue("UNIX Epoch Timestamp");
+
+        cell = header.createCell(1);
+        cell.setCellValue("Date / Time");
+
+        cell = header.createCell(2);
+        cell.setCellValue("Temperature");
+
+        cell = header.createCell(3);
+        cell.setCellValue("QNH pressure");
+
+        cell = header.createCell(4);
+        cell.setCellValue("Humidity");
+
+        cell = header.createCell(5);
+        cell.setCellValue("Wind Direction");
+
+        cell = header.createCell(6);
+        cell.setCellValue("Wind Average Speed");
+
+        cell = header.createCell(7);
+        cell.setCellValue("Wind Gusts");
+
+        File file = new File(context.getExternalFilesDir(null), "test.xls");
+        FileOutputStream fileOutputStream = null;
+
+        try {
+            fileOutputStream = new FileOutputStream(file);
+
+            workbook.write(fileOutputStream);
+        } catch (FileNotFoundException e) {
+            e.printStackTrace();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+
+        return true;
+    }
+
+}

app/src/main/java/cc/pogoda/mobile/pogodacc/web/RestClientConfig.java

@@ -3,6 +3,8 @@ package cc.pogoda.mobile.pogodacc.web;
 import com.google.gson.Gson;
 import com.google.gson.GsonBuilder;
 
+import java.util.concurrent.TimeUnit;
+
 import cc.pogoda.mobile.pogodacc.type.CustomLocalDateTime;
 import cc.pogoda.mobile.pogodacc.web.deserializer.CustomLocalDateTimeDeserializer;
 import okhttp3.OkHttpClient;
@@ -16,7 +18,14 @@ public class RestClientConfig {
 
         Gson gson = new GsonBuilder().registerTypeAdapter(CustomLocalDateTime.class, new CustomLocalDateTimeDeserializer()).setLenient().create();
 
-        OkHttpClient client = new OkHttpClient();
+        OkHttpClient.Builder builder = new OkHttpClient.Builder();
+
+        builder.readTimeout(20, TimeUnit.SECONDS);
+        builder.writeTimeout(20, TimeUnit.SECONDS);
+        builder.connectTimeout(20, TimeUnit.SECONDS);
+        builder.callTimeout(20, TimeUnit.SECONDS);
+
+        OkHttpClient client = builder.build();//new OkHttpClient(builder);
 
         out = new Retrofit.Builder().baseUrl("http://pogoda.cc:8080/").addConverterFactory(GsonConverterFactory.create(gson)).client(client).build();