AbstractFilePickerActivity.java

/*
 * Copyright (c) 2015 Jonas Kalderstam
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package com.nononsenseapps.filepicker;


import android.annotation.TargetApi;
import android.app.Activity;
import android.content.ClipData;
import android.content.Intent;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.support.v4.app.FragmentManager;
import android.support.v7.app.AppCompatActivity;

import java.util.ArrayList;
import java.util.List;

/**
 * An abstract base activity that handles all the fluff you don't care about.
 * <p/>
 * Usage: To start a child activity you could either use an intent starting the
 * activity directly, or you could use an implicit intent with GET_CONTENT, if
 * it
 * is also defined in your manifest. It is defined to be handled here in case
 * you
 * want the user to be able to use other file pickers on the system.
 * <p/>
 * That means using an intent with action GET_CONTENT
 * If you want to be able to select multiple items, include EXTRA_ALLOW_MULTIPLE
 * (default false).
 * <p/>
 * Two non-standard extra arguments are supported as well: EXTRA_ONLY_DIRS
 * (defaults to false)
 * allows only directories to be selected.
 * And EXTRA_START_PATH (default null), which should specify the starting path.
 * <p/>
 * The result of the user's action is returned in onActivityResult intent,
 * access it using getUri.
 * In case of multiple choices, these can be accessed with getClipData
 * containing Uri objects.
 * If running earlier than JellyBean you can access them with
 * getStringArrayListExtra(EXTRA_PATHS)
 *
 * @param <T>
 */
public abstract class AbstractFilePickerActivity<T> extends AppCompatActivity
        implements AbstractFilePickerFragment.OnFilePickedListener {
    public static final String EXTRA_START_PATH =
            "nononsense.intent" + ".START_PATH";
    public static final String EXTRA_MODE = "nononsense.intent.MODE";
    public static final String EXTRA_ALLOW_CREATE_DIR =
            "nononsense.intent" + ".ALLOW_CREATE_DIR";
    // For compatibility
    public static final String EXTRA_ALLOW_MULTIPLE =
            "android.intent.extra" + ".ALLOW_MULTIPLE";
    public static final String EXTRA_PATHS = "nononsense.intent.PATHS";
    public static final int MODE_FILE = AbstractFilePickerFragment.MODE_FILE;
    public static final int MODE_FILE_AND_DIR =
            AbstractFilePickerFragment.MODE_FILE_AND_DIR;
    public static final int MODE_DIR = AbstractFilePickerFragment.MODE_DIR;
    protected static final String TAG = "filepicker_fragment";
    protected String startPath = null;
    protected int mode = AbstractFilePickerFragment.MODE_FILE;
    protected boolean allowCreateDir = false;
    protected boolean allowMultiple = false;

    @Override
    @SuppressWarnings("unchecked")
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.nnf_activity_filepicker);

        Intent intent = getIntent();
        if (intent != null) {
            startPath = intent.getStringExtra(EXTRA_START_PATH);
            mode = intent.getIntExtra(EXTRA_MODE, mode);
            allowCreateDir = intent.getBooleanExtra(EXTRA_ALLOW_CREATE_DIR,
                    allowCreateDir);
            allowMultiple =
                    intent.getBooleanExtra(EXTRA_ALLOW_MULTIPLE, allowMultiple);
        }

        FragmentManager fm = getSupportFragmentManager();
        AbstractFilePickerFragment<T> fragment =
                (AbstractFilePickerFragment<T>) fm.findFragmentByTag(TAG);

        if (fragment == null) {
            fragment =
                    getFragment(startPath, mode, allowMultiple, allowCreateDir);
        }

        if (fragment != null) {
            fm.beginTransaction().replace(R.id.fragment, fragment, TAG)
                    .commit();
        }

        // Default to cancelled
        setResult(Activity.RESULT_CANCELED);
    }

    protected abstract AbstractFilePickerFragment<T> getFragment(
            final String startPath, final int mode, final boolean allowMultiple,
            final boolean allowCreateDir);

    @Override
    public void onSaveInstanceState(Bundle b) {
        super.onSaveInstanceState(b);
    }

    @Override
    public void onFilePicked(final Uri file) {
        Intent i = new Intent();
        i.setData(file);
        setResult(Activity.RESULT_OK, i);
        finish();
    }

    @TargetApi(Build.VERSION_CODES.JELLY_BEAN)
    @Override
    public void onFilesPicked(final List<Uri> files) {
        Intent i = new Intent();
        i.putExtra(EXTRA_ALLOW_MULTIPLE, true);

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN) {
            ClipData clip = null;
            for (Uri file : files) {
                if (clip == null) {
                    clip = new ClipData("Paths", new String[]{},
                            new ClipData.Item(file));
                } else {
                    clip.addItem(new ClipData.Item(file));
                }
            }
            i.setClipData(clip);
        } else {
            ArrayList<String> paths = new ArrayList<>();
            for (Uri file : files) {
                paths.add(file.toString());
            }
            i.putStringArrayListExtra(EXTRA_PATHS, paths);
        }

        setResult(Activity.RESULT_OK, i);
        finish();
    }

    @Override
    public void onCancelled() {
        setResult(Activity.RESULT_CANCELED);
        finish();
    }
}