Java tutorial
/* 50AH-code ========= 50 Android Hacks (http://manning.com/sessa/) book source code Copyright (c) 2012 Manning Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ /* * 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.actionbarsherlock.internal.widget; import android.content.Context; import android.content.res.Configuration; import android.content.res.TypedArray; import android.graphics.drawable.Drawable; import android.text.TextUtils.TruncateAt; import android.util.AttributeSet; import android.view.Gravity; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.view.ViewParent; import android.view.animation.DecelerateInterpolator; import android.view.animation.Interpolator; import android.widget.BaseAdapter; import android.widget.ImageView; import android.widget.LinearLayout; import android.widget.ListView; import com.actionbarsherlock.R; import com.actionbarsherlock.app.ActionBar; import com.actionbarsherlock.internal.nineoldandroids.animation.Animator; import com.actionbarsherlock.internal.nineoldandroids.animation.ObjectAnimator; import com.actionbarsherlock.internal.nineoldandroids.widget.NineHorizontalScrollView; /** * This widget implements the dynamic action bar tab behavior that can change * across different configurations or circumstances. */ public class ScrollingTabContainerView extends NineHorizontalScrollView implements IcsAdapterView.OnItemSelectedListener { //UNUSED private static final String TAG = "ScrollingTabContainerView"; Runnable mTabSelector; private TabClickListener mTabClickListener; private IcsLinearLayout mTabLayout; private IcsSpinner mTabSpinner; private boolean mAllowCollapse; private LayoutInflater mInflater; int mMaxTabWidth; private int mContentHeight; private int mSelectedTabIndex; protected Animator mVisibilityAnim; protected final VisibilityAnimListener mVisAnimListener = new VisibilityAnimListener(); private static final /*Time*/Interpolator sAlphaInterpolator = new DecelerateInterpolator(); private static final int FADE_DURATION = 200; public ScrollingTabContainerView(Context context) { super(context); setHorizontalScrollBarEnabled(false); TypedArray a = getContext().obtainStyledAttributes(null, R.styleable.SherlockActionBar, R.attr.actionBarStyle, 0); setContentHeight(a.getLayoutDimension(R.styleable.SherlockActionBar_height, 0)); a.recycle(); mInflater = LayoutInflater.from(context); mTabLayout = createTabLayout(); addView(mTabLayout, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.MATCH_PARENT)); } @Override public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { final int widthMode = MeasureSpec.getMode(widthMeasureSpec); final boolean lockedExpanded = widthMode == MeasureSpec.EXACTLY; setFillViewport(lockedExpanded); final int childCount = mTabLayout.getChildCount(); if (childCount > 1 && (widthMode == MeasureSpec.EXACTLY || widthMode == MeasureSpec.AT_MOST)) { if (childCount > 2) { mMaxTabWidth = (int) (MeasureSpec.getSize(widthMeasureSpec) * 0.4f); } else { mMaxTabWidth = MeasureSpec.getSize(widthMeasureSpec) / 2; } } else { mMaxTabWidth = -1; } heightMeasureSpec = MeasureSpec.makeMeasureSpec(mContentHeight, MeasureSpec.EXACTLY); final boolean canCollapse = !lockedExpanded && mAllowCollapse; if (canCollapse) { // See if we should expand mTabLayout.measure(MeasureSpec.UNSPECIFIED, heightMeasureSpec); if (mTabLayout.getMeasuredWidth() > MeasureSpec.getSize(widthMeasureSpec)) { performCollapse(); } else { performExpand(); } } else { performExpand(); } final int oldWidth = getMeasuredWidth(); super.onMeasure(widthMeasureSpec, heightMeasureSpec); final int newWidth = getMeasuredWidth(); if (lockedExpanded && oldWidth != newWidth) { // Recenter the tab display if we're at a new (scrollable) size. setTabSelected(mSelectedTabIndex); } } /** * Indicates whether this view is collapsed into a dropdown menu instead * of traditional tabs. * @return true if showing as a spinner */ private boolean isCollapsed() { return mTabSpinner != null && mTabSpinner.getParent() == this; } public void setAllowCollapse(boolean allowCollapse) { mAllowCollapse = allowCollapse; } private void performCollapse() { if (isCollapsed()) return; if (mTabSpinner == null) { mTabSpinner = createSpinner(); } removeView(mTabLayout); addView(mTabSpinner, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.MATCH_PARENT)); if (mTabSpinner.getAdapter() == null) { mTabSpinner.setAdapter(new TabAdapter()); } if (mTabSelector != null) { removeCallbacks(mTabSelector); mTabSelector = null; } mTabSpinner.setSelection(mSelectedTabIndex); } private boolean performExpand() { if (!isCollapsed()) return false; removeView(mTabSpinner); addView(mTabLayout, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.MATCH_PARENT)); setTabSelected(mTabSpinner.getSelectedItemPosition()); return false; } public void setTabSelected(int position) { mSelectedTabIndex = position; final int tabCount = mTabLayout.getChildCount(); for (int i = 0; i < tabCount; i++) { final View child = mTabLayout.getChildAt(i); final boolean isSelected = i == position; child.setSelected(isSelected); if (isSelected) { animateToTab(position); } } } public void setContentHeight(int contentHeight) { mContentHeight = contentHeight; requestLayout(); } private IcsLinearLayout createTabLayout() { final IcsLinearLayout tabLayout = (IcsLinearLayout) LayoutInflater.from(getContext()) .inflate(R.layout.abs__action_bar_tab_bar_view, null); tabLayout.setLayoutParams(new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.MATCH_PARENT)); return tabLayout; } private IcsSpinner createSpinner() { final IcsSpinner spinner = new IcsSpinner(getContext(), null, R.attr.actionDropDownStyle); spinner.setLayoutParams(new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.MATCH_PARENT)); spinner.setOnItemSelectedListener(this); return spinner; } @Override protected void onConfigurationChanged(Configuration newConfig) { super.onConfigurationChanged(newConfig); // Action bar can change size on configuration changes. // Reread the desired height from the theme-specified style. TypedArray a = getContext().obtainStyledAttributes(null, R.styleable.SherlockActionBar, R.attr.actionBarStyle, 0); setContentHeight(a.getLayoutDimension(R.styleable.SherlockActionBar_height, 0)); a.recycle(); } public void animateToVisibility(int visibility) { if (mVisibilityAnim != null) { mVisibilityAnim.cancel(); } if (visibility == VISIBLE) { if (getVisibility() != VISIBLE) { setAlpha(0); } ObjectAnimator anim = ObjectAnimator.ofFloat(this, "alpha", 1); anim.setDuration(FADE_DURATION); anim.setInterpolator(sAlphaInterpolator); anim.addListener(mVisAnimListener.withFinalVisibility(visibility)); anim.start(); } else { ObjectAnimator anim = ObjectAnimator.ofFloat(this, "alpha", 0); anim.setDuration(FADE_DURATION); anim.setInterpolator(sAlphaInterpolator); anim.addListener(mVisAnimListener.withFinalVisibility(visibility)); anim.start(); } } public void animateToTab(final int position) { final View tabView = mTabLayout.getChildAt(position); if (mTabSelector != null) { removeCallbacks(mTabSelector); } mTabSelector = new Runnable() { public void run() { final int scrollPos = tabView.getLeft() - (getWidth() - tabView.getWidth()) / 2; smoothScrollTo(scrollPos, 0); mTabSelector = null; } }; post(mTabSelector); } @Override public void onAttachedToWindow() { super.onAttachedToWindow(); if (mTabSelector != null) { // Re-post the selector we saved post(mTabSelector); } } @Override public void onDetachedFromWindow() { super.onDetachedFromWindow(); if (mTabSelector != null) { removeCallbacks(mTabSelector); } } private TabView createTabView(ActionBar.Tab tab, boolean forAdapter) { //Workaround for not being able to pass a defStyle on pre-3.0 final TabView tabView = (TabView) mInflater.inflate(R.layout.abs__action_bar_tab, null); tabView.init(this, tab, forAdapter); if (forAdapter) { tabView.setBackgroundDrawable(null); tabView.setLayoutParams(new ListView.LayoutParams(ListView.LayoutParams.MATCH_PARENT, mContentHeight)); } else { tabView.setFocusable(true); if (mTabClickListener == null) { mTabClickListener = new TabClickListener(); } tabView.setOnClickListener(mTabClickListener); } return tabView; } public void addTab(ActionBar.Tab tab, boolean setSelected) { TabView tabView = createTabView(tab, false); mTabLayout.addView(tabView, new IcsLinearLayout.LayoutParams(0, LayoutParams.MATCH_PARENT, 1)); if (mTabSpinner != null) { ((TabAdapter) mTabSpinner.getAdapter()).notifyDataSetChanged(); } if (setSelected) { tabView.setSelected(true); } if (mAllowCollapse) { requestLayout(); } } public void addTab(ActionBar.Tab tab, int position, boolean setSelected) { final TabView tabView = createTabView(tab, false); mTabLayout.addView(tabView, position, new IcsLinearLayout.LayoutParams(0, LayoutParams.MATCH_PARENT, 1)); if (mTabSpinner != null) { ((TabAdapter) mTabSpinner.getAdapter()).notifyDataSetChanged(); } if (setSelected) { tabView.setSelected(true); } if (mAllowCollapse) { requestLayout(); } } public void updateTab(int position) { ((TabView) mTabLayout.getChildAt(position)).update(); if (mTabSpinner != null) { ((TabAdapter) mTabSpinner.getAdapter()).notifyDataSetChanged(); } if (mAllowCollapse) { requestLayout(); } } public void removeTabAt(int position) { mTabLayout.removeViewAt(position); if (mTabSpinner != null) { ((TabAdapter) mTabSpinner.getAdapter()).notifyDataSetChanged(); } if (mAllowCollapse) { requestLayout(); } } public void removeAllTabs() { mTabLayout.removeAllViews(); if (mTabSpinner != null) { ((TabAdapter) mTabSpinner.getAdapter()).notifyDataSetChanged(); } if (mAllowCollapse) { requestLayout(); } } @Override public void onItemSelected(IcsAdapterView<?> parent, View view, int position, long id) { TabView tabView = (TabView) view; tabView.getTab().select(); } @Override public void onNothingSelected(IcsAdapterView<?> parent) { } public static class TabView extends LinearLayout { private ScrollingTabContainerView mParent; private ActionBar.Tab mTab; private CapitalizingTextView mTextView; private ImageView mIconView; private View mCustomView; public TabView(Context context, AttributeSet attrs) { //TODO super(context, null, R.attr.actionBarTabStyle); super(context, attrs); } public void init(ScrollingTabContainerView parent, ActionBar.Tab tab, boolean forList) { mParent = parent; mTab = tab; if (forList) { setGravity(Gravity.LEFT | Gravity.CENTER_VERTICAL); } update(); } public void bindTab(ActionBar.Tab tab) { mTab = tab; update(); } @Override public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); // Re-measure if we went beyond our maximum size. if (mParent.mMaxTabWidth > 0 && getMeasuredWidth() > mParent.mMaxTabWidth) { super.onMeasure(MeasureSpec.makeMeasureSpec(mParent.mMaxTabWidth, MeasureSpec.EXACTLY), heightMeasureSpec); } } public void update() { final ActionBar.Tab tab = mTab; final View custom = tab.getCustomView(); if (custom != null) { final ViewParent customParent = custom.getParent(); if (customParent != this) { if (customParent != null) ((ViewGroup) customParent).removeView(custom); addView(custom); } mCustomView = custom; if (mTextView != null) mTextView.setVisibility(GONE); if (mIconView != null) { mIconView.setVisibility(GONE); mIconView.setImageDrawable(null); } } else { if (mCustomView != null) { removeView(mCustomView); mCustomView = null; } final Drawable icon = tab.getIcon(); final CharSequence text = tab.getText(); if (icon != null) { if (mIconView == null) { ImageView iconView = new ImageView(getContext()); LayoutParams lp = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT); lp.gravity = Gravity.CENTER_VERTICAL; iconView.setLayoutParams(lp); addView(iconView, 0); mIconView = iconView; } mIconView.setImageDrawable(icon); mIconView.setVisibility(VISIBLE); } else if (mIconView != null) { mIconView.setVisibility(GONE); mIconView.setImageDrawable(null); } if (text != null) { if (mTextView == null) { CapitalizingTextView textView = new CapitalizingTextView(getContext(), null, R.attr.actionBarTabTextStyle); textView.setEllipsize(TruncateAt.END); LayoutParams lp = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT); lp.gravity = Gravity.CENTER_VERTICAL; textView.setLayoutParams(lp); addView(textView); mTextView = textView; } mTextView.setTextCompat(text); mTextView.setVisibility(VISIBLE); } else if (mTextView != null) { mTextView.setVisibility(GONE); mTextView.setText(null); } if (mIconView != null) { mIconView.setContentDescription(tab.getContentDescription()); } } } public ActionBar.Tab getTab() { return mTab; } } private class TabAdapter extends BaseAdapter { @Override public int getCount() { return mTabLayout.getChildCount(); } @Override public Object getItem(int position) { return ((TabView) mTabLayout.getChildAt(position)).getTab(); } @Override public long getItemId(int position) { return position; } @Override public View getView(int position, View convertView, ViewGroup parent) { if (convertView == null) { convertView = createTabView((ActionBar.Tab) getItem(position), true); } else { ((TabView) convertView).bindTab((ActionBar.Tab) getItem(position)); } return convertView; } } private class TabClickListener implements OnClickListener { public void onClick(View view) { TabView tabView = (TabView) view; tabView.getTab().select(); final int tabCount = mTabLayout.getChildCount(); for (int i = 0; i < tabCount; i++) { final View child = mTabLayout.getChildAt(i); child.setSelected(child == view); } } } protected class VisibilityAnimListener implements Animator.AnimatorListener { private boolean mCanceled = false; private int mFinalVisibility; public VisibilityAnimListener withFinalVisibility(int visibility) { mFinalVisibility = visibility; return this; } @Override public void onAnimationStart(Animator animation) { setVisibility(VISIBLE); mVisibilityAnim = animation; mCanceled = false; } @Override public void onAnimationEnd(Animator animation) { if (mCanceled) return; mVisibilityAnim = null; setVisibility(mFinalVisibility); } @Override public void onAnimationCancel(Animator animation) { mCanceled = true; } @Override public void onAnimationRepeat(Animator animation) { } } }