Subversion Repositories ES

package ch.ffhs.converter.app;

import java.util.HashMap;

import android.app.Activity;

import android.os.Bundle;

import android.text.Editable;

import android.view.KeyEvent;

import android.view.View;

import android.view.View.OnKeyListener;

import android.widget.AdapterView;

import android.widget.AdapterView.OnItemSelectedListener;

import android.widget.EditText;

import android.widget.Spinner;

import ch.ffhs.converter.R;

/**

 * Activity that implements currency conversion

 *

 * @author pelinux

 */

public class CurrenciesActivity extends Activity

{

  /*

   * Constants for mapping value strings to internal IDs

   */

  private static final String VALUE_CHF = "CHF"; //$NON-NLS-1$

  private static final String VALUE_EUR = "EUR"; //$NON-NLS-1$

  private static final String VALUE_USD = "USD"; //$NON-NLS-1$

  private static final int ITEM_CHF = 0;

  private static final int ITEM_EUR = 1;

  private static final int ITEM_USD = 2;

  /**

   * Maps value strings to internal IDs

   */

  private final static HashMap<String, Integer> valueToId =

    new HashMap<String, Integer>();

  static

  {

    CurrenciesActivity.valueToId.put(CurrenciesActivity.VALUE_CHF,

      CurrenciesActivity.ITEM_CHF);

    CurrenciesActivity.valueToId.put(CurrenciesActivity.VALUE_EUR,

      CurrenciesActivity.ITEM_EUR);

    CurrenciesActivity.valueToId.put(CurrenciesActivity.VALUE_USD,

      CurrenciesActivity.ITEM_USD);

  }

  /* Unit spinners (dropdowns) */

  private Spinner spinnerUnit1;

  private Spinner spinnerUnit2;

  /** Called when the activity is first created. */

  @Override

  public void onCreate(Bundle savedInstanceState)

  {

    super.onCreate(savedInstanceState);

    this.setContentView(R.layout.activity_currencies);

    final EditText editValue1 =

      (EditText) this.findViewById(R.id.currencies_edit_value1);

    final EditText editValue2 =

      (EditText) this.findViewById(R.id.currencies_edit_value2);

    final OnKeyListener editValue1OnKey = new OnKeyListener() {

      @Override

      public boolean onKey(View v, int keyCode, KeyEvent event)

      {

        Editable editable1 = ((EditText) v).getText();

        Double value1;

        try

        {

          value1 = Double.parseDouble(editable1.toString());

        }

        catch (NumberFormatException e)

        {

          value1 = null;

        }

        String string2 = ""; //$NON-NLS-1$

        if (value1 != null)

        {

          string2 = CurrenciesActivity.this.getConvertedValue(value1, false);

        }

        editValue2.setText(string2);

        return false;

      }

    };

    editValue1.setOnKeyListener(editValue1OnKey);

    final OnKeyListener editValue2OnKey = new OnKeyListener() {

      @Override

      public boolean onKey(View v, int keyCode, KeyEvent event)

      {

        Editable editable2 = ((EditText) v).getText();

        Double value2;

        try

        {

          value2 = Double.parseDouble(editable2.toString());

        }

        catch (NumberFormatException e)

        {

          value2 = null;

        }

        String string1 = ""; //$NON-NLS-1$

        if (value2 != null)

        {

          string1 = CurrenciesActivity.this.getConvertedValue(value2, true);

        }

        editValue1.setText(string1);

        return false;

      }

    };

    editValue2.setOnKeyListener(editValue2OnKey);

    this.spinnerUnit1 =

      (Spinner) this.findViewById(R.id.currencies_spinner_unit1);

    this.spinnerUnit2 =

      (Spinner) this.findViewById(R.id.currencies_spinner_unit2);

    this.spinnerUnit1.setOnItemSelectedListener(new OnItemSelectedListener() {

      @Override

      public void onItemSelected(AdapterView<?> arg0, View arg1, int arg2,

        long arg3)

      {

        /* Simulate input in second EditText so that first EditText is updated */

        editValue2OnKey.onKey(editValue2, 0, null);

      }

      @Override

      public void onNothingSelected(AdapterView<?> arg0)

      {

        /* no-op */

      }

    });

    this.spinnerUnit2.setSelection(1);

    this.spinnerUnit2.setOnItemSelectedListener(new OnItemSelectedListener() {

      @Override

      public void onItemSelected(AdapterView<?> arg0, View arg1, int arg2,

        long arg3)

      {

        /* Simulate input in first EditText so that second EditText is updated */

        editValue1OnKey.onKey(editValue1, 0, null);

      }

      @Override

      public void onNothingSelected(AdapterView<?> arg0)

      {

        /* no-op */

      }

    });

  }

  /**

   * @param value

   * @return

   */

  private String getConvertedValue(double value, boolean reverse)

  {

    int selectedItemPosition1 = this.spinnerUnit1.getSelectedItemPosition();

    int selectedItemPosition2 = this.spinnerUnit2.getSelectedItemPosition();

    String[] itemArray =

      this.getResources().getStringArray(R.array.currency_units_values);

    String selectedItemValue1 = itemArray[selectedItemPosition1];

    String selectedItemValue2 = itemArray[selectedItemPosition2];

    if (reverse)

    {

      String tmp = selectedItemValue1;

      selectedItemValue1 = selectedItemValue2;

      selectedItemValue2 = tmp;

    }

    int itemId1 = CurrenciesActivity.valueToId.get(selectedItemValue1);

    int itemId2 = CurrenciesActivity.valueToId.get(selectedItemValue2);

    Double newValue = value;

    switch (itemId1)

    {

      case ITEM_CHF:

        switch (itemId2)

        {

          case ITEM_EUR:

            newValue = new Double(value * 0.767842293);

            break;

          case ITEM_USD:

            newValue = new Double(value * 1.03413);

            break;

        }

        break;

      case ITEM_EUR:

        switch (itemId2)

        {

          case ITEM_CHF:

            newValue = new Double(value * 1.30235077);

            break;

          case ITEM_USD:

            newValue = new Double(value * 1.3468);

            break;

        }

        break;

      case ITEM_USD:

        switch (itemId2)

        {

          case ITEM_CHF:

            newValue = new Double(value * 0.966996412);

            break;

          case ITEM_EUR:

            newValue = new Double(value * 0.742500743);

            break;

        }

        break;

    }

    return newValue.toString();

  }

}