src/plugins/db.devices/src/com/motorolamobility/studio/android/db/devices/ui/preferences/DbPreferencePage.java

/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*      http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.motorolamobility.studio.android.db.devices.ui.preferences;

import java.io.File;

import org.eclipse.core.runtime.Path;
import org.eclipse.core.runtime.preferences.InstanceScope;
import org.eclipse.jface.preference.DirectoryFieldEditor;
import org.eclipse.jface.preference.IPreferenceStore;
import org.eclipse.jface.preference.PreferencePage;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.ModifyEvent;
import org.eclipse.swt.events.ModifyListener;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.ui.IWorkbench;
import org.eclipse.ui.IWorkbenchPreferencePage;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.preferences.ScopedPreferenceStore;

import com.motorolamobility.studio.android.db.devices.DbDevicesPlugin;
import com.motorolamobility.studio.android.db.devices.i18n.DbDevicesNLS;

public class DbPreferencePage extends PreferencePage implements IWorkbenchPreferencePage
{

    public static final String LEGACY_PLUGIN_ID = "com.motorola.studio.android.db"; //$NON-NLS-1$

    public static final String LEGACY_DB_PATH_PREFERENCE = LEGACY_PLUGIN_ID + ".dbstudiopath"; //$NON-NLS-1$

    private DirectoryFieldEditor directoryEditor;

    private static final String PREFERENCE_PAGE_HELP = DbDevicesPlugin.PLUGIN_ID
            + ".preference-database"; //$NON-NLS-1$

    public DbPreferencePage()
    {
        setPreferenceStore(DbDevicesPlugin.getDefault().getPreferenceStore());
    }

    @Override
    protected Control createContents(Composite parent)
    {
        Composite main = new Composite(parent, SWT.FILL);
        main.setLayoutData(new GridData(GridData.FILL_BOTH));

        main.setLayout(new GridLayout(1, false));
        directoryEditor =
                new DirectoryFieldEditor(DbDevicesPlugin.DB_TEMP_PATH_PREFERENCE,
                        DbDevicesNLS.UI_PreferencePage_PathLabel, main);
        directoryEditor.getTextControl(main).addModifyListener(new ModifyListener()
        {
            public void modifyText(ModifyEvent e)
            {
                validateDirectory();
            }
        });

        directoryEditor.setStringValue(getPreferenceStore().getString(
                DbDevicesPlugin.DB_TEMP_PATH_PREFERENCE));

        PlatformUI.getWorkbench().getHelpSystem().setHelp(main, PREFERENCE_PAGE_HELP);
        PlatformUI.getWorkbench().getHelpSystem().setHelp(parent, PREFERENCE_PAGE_HELP);

        return main;
    }

    public boolean validateDirectory()
    {
        boolean valid = false;
        if (directoryEditor.getStringValue().trim().length() == 0)
        {
            valid = true;
        }
        else
        {
            try
            {
                File f = new File(directoryEditor.getStringValue());
                if (f.isDirectory())
                {
                    File f2 = new File(directoryEditor.getStringValue() + Path.SEPARATOR + "test"); //$NON-NLS-1$
                    f2.createNewFile();
                    f2.delete();
                    valid = true;
                }
            }
            catch (Exception e)
            {
                valid = false;
            }
        }
        if (!valid)
        {
            setErrorMessage(DbDevicesNLS.ERR_DbPrefPage_InvalidDir);
            setValid(false);
            return false;
        }
        else
        {
            setErrorMessage(null);
            setValid(true);
            return true;
        }
    }

    @Override
    protected void performDefaults()
    {
        getPreferenceStore().setToDefault(DbDevicesPlugin.DB_TEMP_PATH_PREFERENCE);
        directoryEditor.setStringValue(getPreferenceStore().getString(
                DbDevicesPlugin.DB_TEMP_PATH_PREFERENCE));
    }

    @Override
    public boolean performOk()
    {
        boolean canReturn = true;
        if (directoryEditor.getStringValue().trim().length() == 0)
        {
            performDefaults();
        }
        else
        {
            if (!validateDirectory())
            {
                canReturn = false;
            }
            else
            {
                getPreferenceStore().setValue(DbDevicesPlugin.DB_TEMP_PATH_PREFERENCE,
                        directoryEditor.getStringValue());
                canReturn = super.performOk();
            }
        }
        return canReturn;
    }

    public void init(IWorkbench workbench)
    {
        //do nothing
    }

    public static void restoreBackWardPref(IPreferenceStore currentPrefStore)
    {
        IPreferenceStore preferenceStore =
                new ScopedPreferenceStore(InstanceScope.INSTANCE, LEGACY_PLUGIN_ID);
        String backwardDbTempPath = preferenceStore.getString(LEGACY_DB_PATH_PREFERENCE);
        if (!backwardDbTempPath.isEmpty())
        {
            currentPrefStore.setValue(DbDevicesPlugin.DB_TEMP_PATH_PREFERENCE, backwardDbTempPath);

            preferenceStore.setValue(LEGACY_DB_PATH_PREFERENCE, ""); //$NON-NLS-1$
        }
    }

}