Java tutorial
/* * Copyright (C) 2011 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.kii.demo.ui; import java.util.ArrayList; import android.app.AlertDialog; import android.app.Dialog; import android.content.Context; import android.content.DialogInterface; import android.os.Bundle; import android.support.v4.app.DialogFragment; import android.support.v4.app.Fragment; import android.support.v4.app.FragmentActivity; import android.support.v4.app.FragmentPagerAdapter; import android.support.v4.view.ViewPager; import android.view.View; import android.view.ViewGroup; import android.view.Window; import android.widget.TabHost; import android.widget.TabWidget; import com.kii.cloud.engine.ActionType; import com.kii.cloud.engine.KiiCloudClient; import com.kii.demo.R; import com.kii.demo.ui.fragments.FileListFragment; import com.kii.demo.ui.fragments.KiiFileFragment; /** * Demonstrates combining a TabHost with a ViewPager to implement a tab UI that * switches between tabs and also allows the user to perform horizontal flicks * to move between the tabs. */ public class FragmentTabsPager extends FragmentActivity { private FileListFragment mFileFragment = null; private KiiFileFragment mKiiFragment = null; public static class AlertDialogFragment extends DialogFragment { private int id; public static AlertDialogFragment newInstance(int id) { AlertDialogFragment frag = new AlertDialogFragment(); frag.id = id; return frag; } @Override public Dialog onCreateDialog(Bundle savedInstanceState) { switch (id) { case FileListFragment.DIALOG_UPDATE: AlertDialog.Builder builder = new AlertDialog.Builder(getActivity()); builder.setMessage(FileListFragment.getLocalChanges().size() + " file(s) has changed.") .setCancelable(false) .setPositiveButton("Update Now", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int id) { updateFileChange(); } }).setNegativeButton("Cancel", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int id) { dialog.cancel(); } }); AlertDialog dialog = builder.create(); return dialog; default: break; } return null; } private void updateFileChange() { KiiCloudClient client = KiiCloudClient.getInstance(getActivity()); client.updateBody(FileListFragment.getLocalChanges()); } } TabHost mTabHost; ViewPager mViewPager; TabsAdapter mTabsAdapter; private static final String TAG_DEVICE = "device"; private static final String TAG_CLOUD = "cloud"; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); requestWindowFeature(Window.FEATURE_INDETERMINATE_PROGRESS); setProgressBarIndeterminateVisibility(false); setContentView(R.layout.fragment_tabs_pager); mTabHost = (TabHost) findViewById(android.R.id.tabhost); mTabHost.setup(); mViewPager = (ViewPager) findViewById(R.id.pager); mTabsAdapter = new TabsAdapter(this, mTabHost, mViewPager); mTabsAdapter.addTab(mTabHost.newTabSpec(TAG_DEVICE).setIndicator(getString(R.string.tab_device), getResources().getDrawable(R.drawable.device)), FileListFragment.class, null); mTabsAdapter.addTab(mTabHost.newTabSpec(TAG_CLOUD).setIndicator(getString(R.string.tab_cloud), getResources().getDrawable(R.drawable.cloud)), KiiFileFragment.class, null); if (savedInstanceState != null) { mTabHost.setCurrentTabByTag(savedInstanceState.getString("tab")); } KiiCloudClient.getInstance(this).setActivity(this); KiiCloudClient.getInstance(this).refresh(); } @Override protected void onSaveInstanceState(Bundle outState) { super.onSaveInstanceState(outState); outState.putString("tab", mTabHost.getCurrentTabTag()); } static final class TabInfo { private final String tag; private final Class<?> clss; private final Bundle args; TabInfo(String _tag, Class<?> _class, Bundle _args) { tag = _tag; clss = _class; args = _args; } public String getTag() { return tag; } } static class DummyTabFactory implements TabHost.TabContentFactory { private final Context mContext; public DummyTabFactory(Context context) { mContext = context; } @Override public View createTabContent(String tag) { View v = new View(mContext); v.setMinimumWidth(0); v.setMinimumHeight(0); return v; } } /** * This is a helper class that implements the management of tabs and all * details of connecting a ViewPager with associated TabHost. It relies on a * trick. Normally a tab host has a simple API for supplying a View or * Intent that each tab will show. This is not sufficient for switching * between pages. So instead we make the content part of the tab host 0dp * high (it is not shown) and the TabsAdapter supplies its own dummy view to * show as the tab content. It listens to changes in tabs, and takes care of * switch to the correct paged in the ViewPager whenever the selected tab * changes. */ private class TabsAdapter extends FragmentPagerAdapter implements TabHost.OnTabChangeListener, ViewPager.OnPageChangeListener { private final Context mContext; private final TabHost mTabHost; private final ViewPager mViewPager; private final ArrayList<TabInfo> mTabs = new ArrayList<TabInfo>(); public TabsAdapter(FragmentActivity activity, TabHost tabHost, ViewPager pager) { super(activity.getSupportFragmentManager()); mContext = activity; mTabHost = tabHost; mViewPager = pager; mTabHost.setOnTabChangedListener(this); mViewPager.setAdapter(this); mViewPager.setOnPageChangeListener(this); } public void addTab(TabHost.TabSpec tabSpec, Class<?> clss, Bundle args) { tabSpec.setContent(new DummyTabFactory(mContext)); String tag = tabSpec.getTag(); TabInfo info = new TabInfo(tag, clss, args); mTabs.add(info); mTabHost.addTab(tabSpec); notifyDataSetChanged(); } @Override public int getCount() { return mTabs.size(); } @Override public Fragment getItem(int position) { TabInfo info = mTabs.get(position); Fragment f = Fragment.instantiate(mContext, info.clss.getName(), info.args); if (info.clss.getName().contentEquals(FileListFragment.class.getName())) { mFileFragment = (FileListFragment) f; } else if (info.clss.getName().contentEquals(KiiFileFragment.class.getName())) { mKiiFragment = (KiiFileFragment) f; } return f; } @Override public void onTabChanged(String tabId) { int position = mTabHost.getCurrentTab(); mViewPager.setCurrentItem(position); if ((tabId != null)) { if ((tabId.contentEquals(TAG_DEVICE)) && (mFileFragment != null)) { if (mFileFragment.isAdded() && !mFileFragment.isHidden()) { mFileFragment.refreshFilesList(); } } else if ((tabId.contentEquals(TAG_CLOUD)) && (mKiiFragment != null)) { // TODO: if necessary, do KiiFragment.refresh } } } @Override public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) { } @Override public void onPageSelected(int position) { // Unfortunately when TabHost changes the current tab, it kindly // also takes care of putting focus on it when not in touch mode. // The jerk. // This hack tries to prevent this from pulling focus out of our // ViewPager. TabWidget widget = mTabHost.getTabWidget(); int oldFocusability = widget.getDescendantFocusability(); widget.setDescendantFocusability(ViewGroup.FOCUS_BLOCK_DESCENDANTS); mTabHost.setCurrentTab(position); widget.setDescendantFocusability(oldFocusability); } @Override public void onPageScrollStateChanged(int state) { } } public void startProgress(int action) { switch (action) { case ActionType.ACTION_DELETE: setTitle("Deleting"); break; case ActionType.ACTION_DOWNLOAD: setTitle("Downloading"); break; case ActionType.ACTION_EMPTY_TRASH: setTitle("Deleting"); break; case ActionType.ACTION_LIST_FILES: setTitle("Refreshing"); break; case ActionType.ACTION_LIST_TRASH: setTitle("Refreshing"); break; case ActionType.ACTION_RESTORE: setTitle("Restoring"); break; case ActionType.ACTION_TRASH: setTitle("Moving to trash"); break; case ActionType.ACTION_UPDATE: setTitle("Updating"); break; case ActionType.ACTION_UPLOAD: setTitle("Uploading"); break; } setProgressBarIndeterminateVisibility(true); } public void stopProgress() { setProgressBarIndeterminateVisibility(false); setTitle(getString(R.string.app_name)); } }