open-keychain/APG/src/org/thialfihar/android/apg/ui/HelpFragmentHtml.java

/*
 * Copyright (C) 2012 Dominik Schürmann <dominik@dominikschuermann.de>
 *
 * 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 org.thialfihar.android.apg.ui;

import java.io.IOException;
import java.io.InputStream;

import net.nightwhistler.htmlspanner.HtmlSpanner;
import net.nightwhistler.htmlspanner.JellyBeanSpanFixTextView;

import org.thialfihar.android.apg.Constants;
import org.thialfihar.android.apg.helper.OtherHelper;
import org.thialfihar.android.apg.util.Log;

import android.app.Activity;
import android.os.Bundle;
import android.text.method.LinkMovementMethod;
import android.util.TypedValue;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ScrollView;

import com.actionbarsherlock.app.SherlockFragment;

public class HelpFragmentHtml extends SherlockFragment {
    private Activity mActivity;

    private int htmlFile;

    public static final String ARG_HTML_FILE = "htmlFile";

    /**
     * Create a new instance of HelpFragmentHtml, providing "htmlFile" as an argument.
     */
    static HelpFragmentHtml newInstance(int htmlFile) {
        HelpFragmentHtml f = new HelpFragmentHtml();

        // Supply html raw file input as an argument.
        Bundle args = new Bundle();
        args.putInt(ARG_HTML_FILE, htmlFile);
        f.setArguments(args);

        return f;
    }

    /**
     * Workaround for Android Bug. See
     * http://stackoverflow.com/questions/8748064/starting-activity-from
     * -fragment-causes-nullpointerexception
     */
    @Override
    public void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        setUserVisibleHint(true);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        htmlFile = getArguments().getInt(ARG_HTML_FILE);

        // load html from html file from /res/raw
        InputStream inputStreamText = OtherHelper.getInputStreamFromResource(this.getActivity(),
                htmlFile);

        mActivity = getActivity();

        ScrollView scroller = new ScrollView(mActivity);
        JellyBeanSpanFixTextView text = new JellyBeanSpanFixTextView(mActivity);

        // padding
        int padding = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 16, mActivity
                .getResources().getDisplayMetrics());
        text.setPadding(padding, padding, padding, 0);

        scroller.addView(text);

        // load html into textview
        HtmlSpanner htmlSpanner = new HtmlSpanner();
        htmlSpanner.setStripExtraWhiteSpace(true);
        try {
            text.setText(htmlSpanner.fromHtml(inputStreamText));
        } catch (IOException e) {
            Log.e(Constants.TAG, "Error while reading raw resources as stream", e);
        }

        // make links work
        text.setMovementMethod(LinkMovementMethod.getInstance());

        // no flickering when clicking textview for Android < 4
        text.setTextColor(getResources().getColor(android.R.color.black));

        return scroller;
    }
}