Android Open Source - sloop-sql Main Activity

• Back to Development/tool  ↑

From Project

Back to project page sloop-sql.

License

The source code is released under:

SloopSQL is released into the Public Domain. There are no restrictions on how you may use this code, and there is no warranty or guarantee of fitness for anything. USE AT YOUR OWN RISK (and enjoy).

Java Source Code

package com.megginson.sloopsql;
/*w  ww .j  av a 2  s  . c  o  m*/
import android.app.ActionBar;
import android.app.Activity;
import android.app.DialogFragment;
import android.app.Fragment;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.os.Parcelable;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.ViewGroup;
import com.megginson.sloopsql.R;
import java.util.ArrayList;

/**
 * Main container activity for the UI.
 *
 * This activity manages the various fragments that make up the app.
 */
public class MainActivity extends Activity implements TableListFragment.Listener
{

   public final static int TAB_TYPE_QUERY = 1;

  public final static int TAB_TYPE_SCRIPT = 2;

  //
  // Internal state
  //

  /**
   * Serial counter for query tabs
   */
  private int mQueryCounter = 0;

  /**
   * Serial counter for query tabs
   */
  private int mScriptCounter = 0;


  //
  // Activity lifecycle methods
  //

  /**
   * Lifecycle event: activity first created
   */
  @Override
  protected void onCreate(Bundle savedInstanceState)
  {
    super.onCreate(savedInstanceState);

    setContentView(R.layout.main);

    // Specify that tabs should be displayed in the action bar.
    getActionBar().setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
  }

  /**
   * Lifecycle event: activity finally destroyed.
   */
  @Override
  protected void onDestroy()
  {
    super.onDestroy();
  }

  /**
   * Lifecycle event: Android wants us to save the instance state.
   */
  @Override
  protected void onSaveInstanceState(Bundle savedInstanceState)
  {
    super.onSaveInstanceState(savedInstanceState);
    save_tabs(savedInstanceState);
  }

  /**
   * Lifecycle event: Android wants us to restore the instance state.
   */
  @Override
  protected void onRestoreInstanceState(Bundle savedInstanceState)
  {
    super.onRestoreInstanceState(savedInstanceState);
    restore_tabs(savedInstanceState);
  }

  /**
   * Lifecycle event: Android is creating the options menu.
   */
  @Override
  public boolean onCreateOptionsMenu(Menu menu)
  {
    super.onCreateOptionsMenu(menu);

    MenuInflater inflater = getMenuInflater();
    inflater.inflate(R.menu.main_menu, menu);
    return true;    
  }

  /**
   * Lifecycle event: Android is preparing the options menu.
   */
  @Override
  public boolean onPrepareOptionsMenu(Menu menu)
  {
    super.onPrepareOptionsMenu(menu);

    // Hide the close tab item if there are no tabs open
    menu.findItem(R.id.item_close_tab).setVisible(getActionBar().getTabCount() > 0);

    return true;    
  }

  /**
   * Lifecycle event: user has selected a menu item.
   */
  @Override
  public boolean onOptionsItemSelected(MenuItem item)
  {
    super.onOptionsItemSelected(item);

    // Handle item selection
    switch (item.getItemId())
    {
      case R.id.item_add_query:
        do_add_query_tab(null, null);
        return true;
      case R.id.item_add_script:
        do_add_script_tab(null, null);
        return true;
      case R.id.item_close_tab:
        do_close_current_tab();
        return true;
      case R.id.item_list_tables:
        do_list_tables();
        return true;
      default:
        return super.onOptionsItemSelected(item);
    }
  }

  //
  // Listener callbacks for fragments.
  //

  /**
   * The user has selected a table in the table list dialog.
   */
  @Override
  public void onTableSelected(String tableName)
  {
    do_add_query_tab(tableName, "select * from " + tableName);
  }


  //
  // Callbacks for actions a user has performed in the UI
  //

  /**
   * Action: add a new query tab
   */
  private void do_add_query_tab(String title, String queryText)
  {
    if (title == null)
    {
      title = "Query " + (mQueryCounter + 1);
    }
    ActionBar.Tab tab = 
      add_fragment_tab(title, QueryFragment.newInstance(queryText));
    tab.select();
    mQueryCounter++;
  }

  /**
   * Action: add a new query tab
   */
  private void do_add_script_tab(String title, String scriptText)
  {
    if (title == null)
    {
      title = "Script " + (mScriptCounter + 1);
    }
    ActionBar.Tab tab = 
      add_fragment_tab(title, ScriptFragment.newInstance(scriptText));
    tab.select();
    mQueryCounter++;
  }

  /**
   * Action: close the current tab.
   */
  private void do_close_current_tab()
  {
    ActionBar.Tab currentTab = getActionBar().getSelectedTab();
    if (currentTab != null)
    {
      getActionBar().removeTab(currentTab);
      invalidateOptionsMenu();
    }
  }

  /**
   * Action: list tables in this database.
   */
  private void do_list_tables()
  {
    FragmentTransaction ft = getFragmentManager().beginTransaction();
    Fragment prev = getFragmentManager().findFragmentByTag("dialog");
    if (prev != null)
    {
      ft.remove(prev);
    }
    ft.addToBackStack(null);

    // Create and show the dialog.
    DialogFragment newFragment = new TableListFragment();
    newFragment.show(ft, "dialog");
  }


  //
  // Internal utility methods
  //

  /**
   * Restore navigation tab state from a bundle.
   *
   * Android will use this information to recreate an activity after e.g.
   * an orientation change.
   *
   * @param savedInstanceState the bundle from which to restore the state.
   * @see #save_tabs(Bundle)
   */
  private void restore_tabs(Bundle savedInstanceState)
  {
    ((ViewGroup)findViewById(R.id.fragment_container)).removeAllViews();
    mQueryCounter = savedInstanceState.getInt("queryCounter");
    int selectedTabIndex = savedInstanceState.getInt("selectedTabIndex");
    ArrayList<Parcelable> fragmentStates = savedInstanceState.getParcelableArrayList("fragmentStates");
    ArrayList<String> tabTitles = savedInstanceState.getStringArrayList("tabTitles");
    ArrayList<Integer> tabTypes = savedInstanceState.getIntegerArrayList("tabTypes");

    if (tabTitles != null && fragmentStates != null)
    {
      for (int i = 0; i < tabTitles.size() && i < fragmentStates.size(); i++)
      {
        // Get the title
        String tabTitle = tabTitles.get(i);

        // Restore the right kind of fragment
        Fragment fragment;
        if (tabTypes.get(i) == TAB_TYPE_SCRIPT)
        {
          fragment = new ScriptFragment();
        }
        else
        {
          fragment = new QueryFragment();
        }

        // Restore the fragment's internal state
        Fragment.SavedState fragmentState = (Fragment.SavedState)fragmentStates.get(i);
        fragment.setInitialSavedState(fragmentState);

        // Restore the tab
        add_fragment_tab(tabTitle, fragment);
      }
      
      // If we had a selected tab, select it again
      if (selectedTabIndex > -1)
      {
        getActionBar().setSelectedNavigationItem(selectedTabIndex);
      }
    }
  }

  /**
   * Save navigation tab state to a bundle.
   *
   * This saved information lets us restore after e.g. an orientation
   * change.
   *
   * We will save the tab titles and the tags of the associated fragments, 
   * all of which must have called {@link Fragment#setRetainState(boolean)}
   * with true in their {@link Fragment#onActivityCreated} methods to tell
   * Android to preserve their internal state after the parent activity
   * terminates.
   *
   * @param savedInstanceState the bundle to which to save the state.
   * @see #restore_tabs(Bundle)
   */
  private void save_tabs(Bundle savedInstanceState)
  {
    ArrayList<String> tabTitles = new ArrayList<String>();
    ArrayList<Integer> tabTypes = new ArrayList<Integer>();
    ArrayList<Parcelable> fragmentStates = new ArrayList<Parcelable>();

    for (int i = 0; i < getActionBar().getTabCount(); i++)
    {
      ActionBar.Tab tab = getActionBar().getTabAt(i);
      TabListener listener = (TabListener)tab.getTag();
      String tabTitle = tab.getText().toString();
      Fragment fragment = listener.getFragment();

      if (fragment instanceof ScriptFragment)
      {
        tabTypes.add(TAB_TYPE_SCRIPT);
      }
      else
      {
        tabTypes.add(TAB_TYPE_QUERY);
      }

      Fragment.SavedState fragmentState = getFragmentManager().saveFragmentInstanceState(fragment);
      tabTitles.add(tabTitle);
      fragmentStates.add(fragmentState);
    }

    savedInstanceState.putInt("queryCounter", mQueryCounter);
    savedInstanceState.putInt("selectedTabIndex", getActionBar().getSelectedNavigationIndex());
    savedInstanceState.putStringArrayList("tabTitles", tabTitles);
    savedInstanceState.putIntegerArrayList("tabTypes", tabTypes);
    savedInstanceState.putParcelableArrayList("fragmentStates", fragmentStates);
  }

  /**
   * Create and add a new action bar tab.
   *
   * This method adds a new {@link TabListener} to the fragment, which
   * we can retrieve using {@link Fragment#getTag} (not to be confused
   * with the tag in the {@link FragmentManager}).
   *
   * This method automatically refreshes the options menu.
   *
   * @param label The tab label/title.
   * @param fragment The {@link Fragment} associated with the tab.
   * @return The new tab.
   */
  private ActionBar.Tab add_fragment_tab(String label, Fragment fragment)
  {
    TabListener listener = new TabListener(this, R.id.fragment_container, fragment);
    ActionBar.Tab tab = getActionBar().newTab()
      .setText(label)
      .setTabListener(listener);
    // there's no getTabListener() method, so save a copy here
    tab.setTag(listener);
    getActionBar().addTab(tab);
    invalidateOptionsMenu();
    return tab;
  }

}

Java Source Code List

• Back to Development/tool  ↑