Java tutorial
/* * Copyright (C) 2008 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.jikexueyuan.jikecalculator; import android.app.Activity; import android.content.res.Resources; import android.content.res.TypedArray; import android.os.Bundle; import android.os.Parcelable; import android.support.v4.view.PagerAdapter; import android.support.v4.view.ViewPager; import android.util.Log; import android.view.KeyEvent; import android.view.LayoutInflater; import android.view.Menu; import android.view.MenuItem; import android.view.View; import android.view.View.OnClickListener; import android.view.ViewGroup; import android.view.WindowManager; import android.widget.PopupMenu; import android.widget.PopupMenu.OnMenuItemClickListener; public class Calculator extends Activity implements PanelSwitcher.Listener, Logic.Listener, OnClickListener, OnMenuItemClickListener { EventListener mListener = new EventListener(); private CalculatorDisplay mDisplay; private Persist mPersist; private History mHistory; private Logic mLogic; private ViewPager mPager; private View mClearButton; private View mBackspaceButton; private View mOverflowMenuButton; static final int BASIC_PANEL = 0; static final int ADVANCED_PANEL = 1; private static final String LOG_TAG = "Calculator"; private static final boolean DEBUG = false; private static final boolean LOG_ENABLED = false; private static final String STATE_CURRENT_VIEW = "state-current-view"; @Override public void onCreate(Bundle state) { super.onCreate(state); // Disable IME for this application getWindow().setFlags(WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM, WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM); setContentView(R.layout.main); mPager = (ViewPager) findViewById(R.id.panelswitch); if (mPager != null) { mPager.setAdapter(new PageAdapter(mPager)); } else { // Single page UI final TypedArray buttons = getResources().obtainTypedArray(R.array.buttons); for (int i = 0; i < buttons.length(); i++) { setOnClickListener(null, buttons.getResourceId(i, 0)); } buttons.recycle(); } if (mClearButton == null) { mClearButton = findViewById(R.id.clear); mClearButton.setOnClickListener(mListener); mClearButton.setOnLongClickListener(mListener); } if (mBackspaceButton == null) { mBackspaceButton = findViewById(R.id.del); mBackspaceButton.setOnClickListener(mListener); mBackspaceButton.setOnLongClickListener(mListener); } mPersist = new Persist(this); mPersist.load(); mHistory = mPersist.history; mDisplay = (CalculatorDisplay) findViewById(R.id.display); mLogic = new Logic(this, mHistory, mDisplay); mLogic.setListener(this); mLogic.setDeleteMode(mPersist.getDeleteMode()); mLogic.setLineLength(mDisplay.getMaxDigits()); HistoryAdapter historyAdapter = new HistoryAdapter(this, mHistory, mLogic); mHistory.setObserver(historyAdapter); if (mPager != null) { mPager.setCurrentItem(state == null ? 0 : state.getInt(STATE_CURRENT_VIEW, 0)); } mListener.setHandler(mLogic, mPager); mDisplay.setOnKeyListener(mListener); mLogic.resumeWithHistory(); updateDeleteMode(); SoundManager.getInstance().initSounds(this); } private void updateDeleteMode() { if (mLogic.getDeleteMode() == Logic.DELETE_MODE_BACKSPACE) { mClearButton.setVisibility(View.GONE); mBackspaceButton.setVisibility(View.VISIBLE); } else { mClearButton.setVisibility(View.VISIBLE); mBackspaceButton.setVisibility(View.GONE); } } void setOnClickListener(View root, int id) { final View target = root != null ? root.findViewById(id) : findViewById(id); target.setOnClickListener(mListener); } @Override public boolean onCreateOptionsMenu(Menu menu) { super.onCreateOptionsMenu(menu); getMenuInflater().inflate(R.menu.menu, menu); return true; } @Override public boolean onPrepareOptionsMenu(Menu menu) { super.onPrepareOptionsMenu(menu); menu.findItem(R.id.basic).setVisible(!getBasicVisibility()); menu.findItem(R.id.advanced).setVisible(!getAdvancedVisibility()); return true; } private void createFakeMenu() { mOverflowMenuButton = findViewById(R.id.overflow_menu); if (mOverflowMenuButton != null) { mOverflowMenuButton.setVisibility(View.VISIBLE); mOverflowMenuButton.setOnClickListener(this); } } @Override public void onClick(View v) { switch (v.getId()) { case R.id.overflow_menu: PopupMenu menu = constructPopupMenu(); if (menu != null) { menu.show(); } break; } } private PopupMenu constructPopupMenu() { final PopupMenu popupMenu = new PopupMenu(this, mOverflowMenuButton); mOverflowMenuButton.setOnTouchListener(popupMenu.getDragToOpenListener()); final Menu menu = popupMenu.getMenu(); popupMenu.inflate(R.menu.menu); popupMenu.setOnMenuItemClickListener(this); onPrepareOptionsMenu(menu); return popupMenu; } @Override public boolean onMenuItemClick(MenuItem item) { return onOptionsItemSelected(item); } private boolean getBasicVisibility() { return mPager != null && mPager.getCurrentItem() == BASIC_PANEL; } private boolean getAdvancedVisibility() { return mPager != null && mPager.getCurrentItem() == ADVANCED_PANEL; } @Override public boolean onOptionsItemSelected(MenuItem item) { switch (item.getItemId()) { case R.id.clear_history: mHistory.clear(); mLogic.onClear(); break; case R.id.basic: if (!getBasicVisibility() && mPager != null) { mPager.setCurrentItem(BASIC_PANEL, true); } break; case R.id.advanced: if (!getAdvancedVisibility() && mPager != null) { mPager.setCurrentItem(ADVANCED_PANEL, true); } break; } return super.onOptionsItemSelected(item); } @Override protected void onSaveInstanceState(Bundle state) { super.onSaveInstanceState(state); if (mPager != null) { state.putInt(STATE_CURRENT_VIEW, mPager.getCurrentItem()); } } @Override public void onPause() { super.onPause(); mLogic.updateHistory(); mPersist.setDeleteMode(mLogic.getDeleteMode()); mPersist.save(); } @Override public boolean onKeyDown(int keyCode, KeyEvent keyEvent) { if (keyCode == KeyEvent.KEYCODE_BACK && getAdvancedVisibility() && mPager != null) { mPager.setCurrentItem(BASIC_PANEL); return true; } else { return super.onKeyDown(keyCode, keyEvent); } } static void log(String message) { if (LOG_ENABLED) { Log.v(LOG_TAG, message); } } @Override public void onChange() { invalidateOptionsMenu(); } @Override public void onDeleteModeChange() { updateDeleteMode(); } class PageAdapter extends PagerAdapter { private View mSimplePage; private View mAdvancedPage; public PageAdapter(ViewPager parent) { final LayoutInflater inflater = LayoutInflater.from(parent.getContext()); final View simplePage = inflater.inflate(R.layout.simple_pad, parent, false); final View advancedPage = inflater.inflate(R.layout.advanced_pad, parent, false); mSimplePage = simplePage; mAdvancedPage = advancedPage; final Resources res = getResources(); final TypedArray simpleButtons = res.obtainTypedArray(R.array.simple_buttons); for (int i = 0; i < simpleButtons.length(); i++) { setOnClickListener(simplePage, simpleButtons.getResourceId(i, 0)); } simpleButtons.recycle(); final TypedArray advancedButtons = res.obtainTypedArray(R.array.advanced_buttons); for (int i = 0; i < advancedButtons.length(); i++) { setOnClickListener(advancedPage, advancedButtons.getResourceId(i, 0)); } advancedButtons.recycle(); final View clearButton = simplePage.findViewById(R.id.clear); if (clearButton != null) { mClearButton = clearButton; } final View backspaceButton = simplePage.findViewById(R.id.del); if (backspaceButton != null) { mBackspaceButton = backspaceButton; } } @Override public int getCount() { return 2; } @Override public void startUpdate(View container) { } @Override public Object instantiateItem(View container, int position) { final View page = position == 0 ? mSimplePage : mAdvancedPage; ((ViewGroup) container).addView(page); return page; } @Override public void destroyItem(View container, int position, Object object) { ((ViewGroup) container).removeView((View) object); } @Override public void finishUpdate(View container) { } @Override public boolean isViewFromObject(View view, Object object) { return view == object; } @Override public Parcelable saveState() { return null; } @Override public void restoreState(Parcelable state, ClassLoader loader) { } } }