Java tutorial
/* * Copyright (C) 2015 Zhang Rui <bbcallen@gmail.com> * * 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.iqiyi.demo.fileoperator.ui.fragment; import android.app.Activity; import android.content.Context; import android.database.Cursor; import android.os.Bundle; import android.support.annotation.Nullable; import android.support.v4.app.Fragment; import android.support.v4.app.LoaderManager; import android.support.v4.content.Loader; import android.support.v4.widget.SimpleCursorAdapter; import android.text.TextUtils; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.AdapterView; import android.widget.ImageView; import android.widget.ListView; import android.widget.TextView; import com.iqiyi.demo.fileoperator.event.FileExplorerEvents; import com.iqiyi.demo.fileoperator.content.PathCursor; import com.iqiyi.demo.fileoperator.content.PathCursorLoader; import com.iqiyi.demo.fileoperator.R; import java.io.File; public class FileListFragment extends Fragment implements LoaderManager.LoaderCallbacks<Cursor> { private static final String ARG_PATH = "path"; private TextView mPathView; private ListView mFileListView; private VideoAdapter mAdapter; private String mPath; public static FileListFragment newInstance(String path) { FileListFragment f = new FileListFragment(); // Supply index input as an argument. Bundle args = new Bundle(); args.putString(ARG_PATH, path); f.setArguments(args); return f; } @Nullable @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { ViewGroup viewGroup = (ViewGroup) inflater.inflate(R.layout.fragment_file_list, container, false); mPathView = (TextView) viewGroup.findViewById(R.id.path_view); mFileListView = (ListView) viewGroup.findViewById(R.id.file_list_view); mPathView.setVisibility(View.VISIBLE); return viewGroup; } @Override public void onActivityCreated(@Nullable Bundle savedInstanceState) { super.onActivityCreated(savedInstanceState); Activity activity = getActivity(); Bundle bundle = getArguments(); if (bundle != null) { mPath = bundle.getString(ARG_PATH); mPath = new File(mPath).getAbsolutePath(); mPathView.setText(mPath); } mAdapter = new VideoAdapter(activity); mFileListView.setAdapter(mAdapter); mFileListView.setOnItemClickListener(new AdapterView.OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, final int position, final long id) { String path = mAdapter.getFilePath(position); if (TextUtils.isEmpty(path)) return; FileExplorerEvents.getBus().post(new FileExplorerEvents.OnClickFile(path)); } }); getLoaderManager().initLoader(1, null, this); } @Override public Loader<Cursor> onCreateLoader(int id, Bundle args) { if (TextUtils.isEmpty(mPath)) return null; return new PathCursorLoader(getActivity(), mPath); } @Override public void onLoadFinished(Loader<Cursor> loader, Cursor data) { mAdapter.swapCursor(data); mAdapter.notifyDataSetChanged(); } @Override public void onLoaderReset(Loader<Cursor> loader) { } final class VideoAdapter extends SimpleCursorAdapter { final class ViewHolder { public ImageView iconImageView; public TextView nameTextView; } public VideoAdapter(Context context) { super(context, android.R.layout.simple_list_item_2, null, new String[] { PathCursor.CN_FILE_NAME, PathCursor.CN_FILE_PATH }, new int[] { android.R.id.text1, android.R.id.text2 }, 0); } @Override public View getView(int position, View convertView, ViewGroup parent) { View view = convertView; if (view == null) { LayoutInflater inflater = LayoutInflater.from(parent.getContext()); view = inflater.inflate(R.layout.fragment_file_list_item, parent, false); } ViewHolder viewHolder = (ViewHolder) view.getTag(); if (viewHolder == null) { viewHolder = new ViewHolder(); viewHolder.iconImageView = (ImageView) view.findViewById(R.id.icon); viewHolder.nameTextView = (TextView) view.findViewById(R.id.name); } if (isDirectory(position)) { viewHolder.iconImageView.setImageResource(R.mipmap.ic_theme_folder); } else if (isVideo(position)) { viewHolder.iconImageView.setImageResource(R.mipmap.ic_theme_play_arrow); } else { viewHolder.iconImageView.setImageResource(R.mipmap.ic_theme_description); } viewHolder.nameTextView.setText(getFileName(position)); return view; } @Override public long getItemId(int position) { final Cursor cursor = moveToPosition(position); if (cursor == null) return 0; return cursor.getLong(PathCursor.CI_ID); } Cursor moveToPosition(int position) { final Cursor cursor = getCursor(); if (cursor.getCount() == 0 || position >= cursor.getCount()) { return null; } cursor.moveToPosition(position); return cursor; } public boolean isDirectory(int position) { final Cursor cursor = moveToPosition(position); if (cursor == null) return true; return cursor.getInt(PathCursor.CI_IS_DIRECTORY) != 0; } public boolean isVideo(int position) { final Cursor cursor = moveToPosition(position); if (cursor == null) return true; return cursor.getInt(PathCursor.CI_IS_VIDEO) != 0; } public String getFileName(int position) { final Cursor cursor = moveToPosition(position); if (cursor == null) return ""; return cursor.getString(PathCursor.CI_FILE_NAME); } public String getFilePath(int position) { final Cursor cursor = moveToPosition(position); if (cursor == null) return ""; return cursor.getString(PathCursor.CI_FILE_PATH); } } }