/***
Copyright (c) 2012-16 CommonsWare, LLC
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.
Covered in detail in the book _The Busy Coder's Guide to Android Development_
https://commonsware.com/Android
*/
package com.commonsware.android.rvp;
import android.app.Activity;
import android.os.Bundle;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.PagerSnapHelper;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.SnapHelper;
import android.view.Menu;
import android.view.MenuItem;
import com.commonsware.cwac.crossport.design.widget.TabLayout;
public class MainActivity extends Activity {
private static final String STATE_ADAPTER="adapter";
private final SnapHelper snapperCarr=new PagerSnapHelper();
private RecyclerView pager;
private PageAdapter adapter;
private LinearLayoutManager layoutManager;
private TabLayout tabs;
private MenuItem remove;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
pager=(RecyclerView)findViewById(R.id.pager);
layoutManager=
new LinearLayoutManager(this, LinearLayoutManager.HORIZONTAL, false);
pager.setLayoutManager(layoutManager);
snapperCarr.attachToRecyclerView(pager);
adapter=new PageAdapter(pager, getLayoutInflater());
pager.setAdapter(adapter);
pager.setHasFixedSize(true);
tabs=(TabLayout)findViewById(R.id.tabs);
if (savedInstanceState==null) {
for (int i=0; i<adapter.getItemCount(); i++) {
tabs.addTab(tabs.newTab().setText(adapter.getTabText(i)));
}
}
tabs.addOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
@Override
public void onTabSelected(TabLayout.Tab tab) {
pager.smoothScrollToPosition(tab.getPosition());
}
@Override
public void onTabUnselected(TabLayout.Tab tab) {
// unused
}
@Override
public void onTabReselected(TabLayout.Tab tab) {
// unused
}
});
pager.setOnScrollListener(new RecyclerView.OnScrollListener() {
@Override
public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
int tab=getCurrentPosition();
if (tab>=0 && tab<tabs.getTabCount()) {
tabs.getTabAt(tab).select();
}
}
});
}
@Override
protected void onSaveInstanceState(Bundle state) {
super.onSaveInstanceState(state);
Bundle adapterState=new Bundle();
adapter.onSaveInstanceState(adapterState);
state.putBundle(STATE_ADAPTER, adapterState);
}
@Override
protected void onRestoreInstanceState(Bundle state) {
super.onRestoreInstanceState(state);
adapter.onRestoreInstanceState(state.getBundle(STATE_ADAPTER));
tabs.removeAllTabs();
for (int i=0;i<adapter.getItemCount();i++) {
tabs.addTab(tabs.newTab().setText(adapter.getTabText(i)));
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.actions, menu);
remove=menu.findItem(R.id.remove);
return(super.onCreateOptionsMenu(menu));
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch(item.getItemId()) {
case R.id.add:
add();
return(true);
case R.id.split:
split();
return(true);
case R.id.swap:
swap();
return(true);
case R.id.remove:
remove();
return(true);
}
return(super.onOptionsItemSelected(item));
}
private int getCurrentPosition() {
return(layoutManager.findFirstCompletelyVisibleItemPosition());
}
private void add() {
int current=getCurrentPosition();
adapter.insert(current);
tabs.addTab(tabs.newTab().setText(adapter.getTabText(current)), current);
updateRemoveMenuItem();
}
private void split() {
int newPosition=getCurrentPosition()+1;
adapter.clone(newPosition-1);
tabs.addTab(tabs.newTab().setText(adapter.getTabText(newPosition)), newPosition);
updateRemoveMenuItem();
}
private void swap() {
int first=getCurrentPosition();
int second;
if (first>=adapter.getItemCount()-1) {
second=first;
first--;
}
else {
second=first+1;
}
adapter.swap(first, second);
TabLayout.Tab firstTab=tabs.getTabAt(first);
TabLayout.Tab secondTab=tabs.getTabAt(second);
CharSequence firstText=firstTab.getText();
firstTab.setText(secondTab.getText());
secondTab.setText(firstText);
}
private void remove() {
final int current=getCurrentPosition();
tabs.removeTabAt(current);
adapter.remove(current);
if (current<adapter.getItemCount()) {
pager.scrollToPosition(current);
}
updateRemoveMenuItem();
}
private void updateRemoveMenuItem() {
remove.setEnabled(adapter.getItemCount()>1);
}
}