Java tutorial
/* * Copyright 2013 Matthew Precious * * 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.mattprecious.prioritysms.fragment; import android.app.Activity; import android.os.Bundle; import android.support.v4.app.Fragment; import android.support.v4.app.FragmentManager; import android.support.v4.app.FragmentPagerAdapter; import android.support.v4.view.ViewPager; import android.text.Editable; import android.text.TextWatcher; import android.util.Log; import android.util.SparseArray; import android.view.LayoutInflater; import android.view.View; import android.view.View.OnClickListener; import android.view.View.OnFocusChangeListener; import android.view.ViewGroup; import android.widget.EditText; import android.widget.ImageButton; import butterknife.ButterKnife; import butterknife.InjectView; import com.actionbarsherlock.view.Menu; import com.actionbarsherlock.view.MenuInflater; import com.actionbarsherlock.view.MenuItem; import com.mattprecious.prioritysms.R; import com.mattprecious.prioritysms.model.BaseProfile; import com.viewpagerindicator.TabPageIndicator; import de.keyboardsurfer.android.widget.crouton.Crouton; import de.keyboardsurfer.android.widget.crouton.Style; import java.lang.ref.WeakReference; import java.util.ArrayList; import java.util.List; public class ProfileDetailFragment extends BaseFragment { public static final String EXTRA_PROFILE = "profile"; private static final String TAG = ProfileDetailFragment.class.getSimpleName(); private static final String STATE_PROFILE = "profile"; private static final int ERROR_FLAG_NAME = 1; private static final int ERROR_FLAG_PAGER = 1 << 1; public interface Callbacks { public void onNameUpdated(String name); public void onDiscard(); public void onDelete(BaseProfile profile); public void onSave(); } private static Callbacks dummyCallbacks = new Callbacks() { @Override public void onNameUpdated(String name) { } @Override public void onDiscard() { } @Override public void onDelete(BaseProfile profile) { } @Override public void onSave() { } }; public static ProfileDetailFragment create(BaseProfile profile) { Bundle args = new Bundle(); args.putParcelable(ProfileDetailFragment.EXTRA_PROFILE, profile); ProfileDetailFragment fragment = new ProfileDetailFragment(); fragment.setArguments(args); return fragment; } @InjectView(R.id.profile_name_container) View nameContainer; @InjectView(R.id.profile_name) EditText nameText; @InjectView(R.id.close_rename) ImageButton closeRenameButton; @InjectView(R.id.pager) ViewPager pager; @InjectView(R.id.indicator) TabPageIndicator titleIndicator; private Callbacks callbacks = dummyCallbacks; private BaseProfile profile; private ProfilePagerAdapter pagerAdapter; private int errorFlags = 0; private int customErrorResId; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setHasOptionsMenu(true); if (savedInstanceState == null) { Bundle args = getArguments(); if (args == null || !args.containsKey(EXTRA_PROFILE)) { throw new IllegalArgumentException(String.format("must provide %s as intent extra", EXTRA_PROFILE)); } else { profile = args.getParcelable(EXTRA_PROFILE); } } else { profile = savedInstanceState.getParcelable(STATE_PROFILE); } pagerAdapter = new ProfilePagerAdapter(getFragmentManager()); } @Override public void onAttach(Activity activity) { super.onAttach(activity); if (!(activity instanceof Callbacks)) { throw new IllegalStateException("Activity must implement fragment's callbacks."); } callbacks = (Callbacks) activity; } @Override public void onDetach() { super.onDetach(); callbacks = dummyCallbacks; } @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View rootView = inflater.inflate(R.layout.fragment_profile_detail, container, false); ButterKnife.inject(this, rootView); callbacks.onNameUpdated(profile.getName()); nameContainer.setVisibility((profile.getName() == null) ? View.VISIBLE : View.GONE); nameText.setText(profile.getName()); nameText.setOnFocusChangeListener(new OnFocusChangeListener() { @Override public void onFocusChange(View v, boolean hasFocus) { if (!hasFocus) { validateName(); } } }); nameText.addTextChangedListener(new TextWatcher() { @Override public void onTextChanged(CharSequence s, int start, int before, int count) { } @Override public void beforeTextChanged(CharSequence s, int start, int count, int after) { } @Override public void afterTextChanged(Editable s) { callbacks.onNameUpdated(s.toString()); } }); closeRenameButton.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { closeRename(); } }); pager.setAdapter(pagerAdapter); titleIndicator.setViewPager(pager); return rootView; } @Override public void onSaveInstanceState(Bundle outState) { super.onSaveInstanceState(outState); updateProfile(); outState.putParcelable(STATE_PROFILE, profile); } @Override public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) { super.onCreateOptionsMenu(menu, inflater); inflater.inflate(R.menu.menu_profile_detail, menu); } @Override public boolean onOptionsItemSelected(MenuItem item) { switch (item.getItemId()) { case R.id.menu_discard: callbacks.onDiscard(); return true; case R.id.menu_save: validate(); if (errorFlags > 0) { int errorResId = customErrorResId > 0 ? customErrorResId : R.string.detail_error; Crouton.showText(getActivity(), errorResId, Style.ALERT); } else { updateProfile(); profile.save(getActivity()); callbacks.onSave(); } return true; case R.id.menu_delete: profile.delete(getActivity()); // the profile could have been updated with local changes, grab // the original one callbacks.onDelete((BaseProfile) getArguments().getParcelable(EXTRA_PROFILE)); return true; case R.id.menu_rename: if (nameContainer.getVisibility() == View.VISIBLE) { closeRename(); } else { nameContainer.setVisibility(View.VISIBLE); } return true; default: return super.onOptionsItemSelected(item); } } private void updateProfile() { profile.setName(nameText.getText().toString()); for (BaseDetailFragment fragment : pagerAdapter.getRegisteredFragments()) { fragment.updateProfile(profile); } } private void closeRename() { validateName(); if (!isError(ERROR_FLAG_NAME)) { nameContainer.setVisibility(View.GONE); } } private void setError(int flag) { errorFlags |= flag; } private void removeError(int flag) { errorFlags &= ~flag; } private boolean isError(int flag) { return (errorFlags & flag) > 0; } private void validate() { customErrorResId = 0; validateName(); validatePager(); } private void validateName() { if (nameText.getText().length() == 0) { nameText.setError(getString(R.string.detail_error_empty_name)); setError(ERROR_FLAG_NAME); } else { nameText.setError(null); removeError(ERROR_FLAG_NAME); } } private void validatePager() { int i = 0; for (BaseDetailFragment fragment : pagerAdapter.getRegisteredFragments()) { ValidationResponse response = fragment.validate(); if (!response.isValid()) { setError(ERROR_FLAG_PAGER); pager.setCurrentItem(i); if (customErrorResId == 0) { customErrorResId = response.getCustomErrorResId(); } return; } i++; } removeError(ERROR_FLAG_PAGER); } private class ProfilePagerAdapter extends FragmentPagerAdapter { private static final int NUM_FRAGMENTS = 2; SparseArray<WeakReference<Fragment>> mRegisteredFragments = new SparseArray<WeakReference<Fragment>>(); private final String[] mTitles = new String[NUM_FRAGMENTS]; public ProfilePagerAdapter(FragmentManager fm) { super(fm); mTitles[0] = getString(R.string.detail_tab_conditions); mTitles[1] = getString(R.string.detail_tab_actions); } @Override public Fragment getItem(int position) { switch (position) { case 0: return ProfileDetailConditionsFragment.create(profile); case 1: return ProfileDetailActionsFragment.create(profile); default: Log.e(TAG, "invalid getItem position: " + position); return null; } } @Override public Object instantiateItem(ViewGroup container, int position) { Fragment fragment = (Fragment) super.instantiateItem(container, position); mRegisteredFragments.put(position, new WeakReference<Fragment>(fragment)); return fragment; } @Override public void destroyItem(ViewGroup container, int position, Object object) { mRegisteredFragments.remove(position); super.destroyItem(container, position, object); } @Override public CharSequence getPageTitle(int position) { if (position >= 0 && position < NUM_FRAGMENTS) { return mTitles[position]; } Log.e(TAG, "invalid getPageTitle position: " + position); return null; } @Override public int getCount() { return NUM_FRAGMENTS; } public List<BaseDetailFragment> getRegisteredFragments() { List<BaseDetailFragment> list = new ArrayList<>(mRegisteredFragments.size()); for (int i = 0; i < mRegisteredFragments.size(); i++) { BaseDetailFragment fragment = getRegisteredFragment(i); if (fragment != null) { list.add(fragment); } } return list; } public BaseDetailFragment getRegisteredFragment(int position) { Fragment fragment = mRegisteredFragments.get(position).get(); if (fragment == null) { Log.e(TAG, String.format("fragment at position %d was cleared", position)); return null; } return (BaseDetailFragment) fragment; } } public abstract static class BaseDetailFragment extends BaseFragment { public abstract void updateProfile(BaseProfile profile); public abstract ValidationResponse validate(); } public static class ValidationResponse { private boolean valid; private int customErrorResId; public ValidationResponse(boolean valid) { this(valid, 0); } public ValidationResponse(boolean valid, int customErrorResId) { this.valid = valid; this.customErrorResId = customErrorResId; } public boolean isValid() { return valid; } public int getCustomErrorResId() { return customErrorResId; } } }