Java tutorial
/* * Copyright (C) 2013 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.wewe.android.widget; import android.content.Context; import android.graphics.Typeface; import android.support.v4.view.PagerAdapter; import android.support.v4.view.ViewPager; import android.text.TextUtils; import android.util.AttributeSet; import android.util.SparseArray; import android.util.TypedValue; import android.view.Gravity; import android.view.LayoutInflater; import android.view.View; import android.view.ViewGroup; import android.widget.HorizontalScrollView; import android.widget.ImageView; import android.widget.LinearLayout; import android.widget.TextView; import com.wewe.android.R; /** * To be used with ViewPager to provide a tab indicator component which give constant feedback as to * the user's scroll progress. * <p/> * To use the component, simply add it to your view hierarchy. Then in your * {@link android.app.Activity} or {@link android.support.v4.app.Fragment} call * {@link #setViewPager(android.support.v4.view.ViewPager)} providing it the ViewPager this layout is being used for. * <p/> * The views used as tabs can be customized by calling {@link #setCustomTabView(int, int)}, * providing the layout ID of your custom layout. */ public class SlidingTabLayout extends HorizontalScrollView { /** * Allows complete control over the colors drawn in the tab layout. Set with * {@link #setCustomTabColorizer(TabColorizer)}. */ public interface TabColorizer { /** * @return return the color of the indicator used when {@code position} is selected. */ int getIndicatorColor(int position); } private static final int TITLE_OFFSET_DIPS = 24; private static final int TAB_VIEW_PADDING_DIPS = 16; private static final int TAB_VIEW_TEXT_SIZE_SP = 12; private int mTitleOffset; public interface OnTabIconListener { int getPageIcon(int position); } private OnTabIconListener mIconListener; private int mTabViewIconId; private int mTabViewLayoutId; private int mTabViewTextViewId; private boolean mDistributeEvenly; private ViewPager mViewPager; private SparseArray<String> mContentDescriptions = new SparseArray<String>(); private ViewPager.OnPageChangeListener mViewPagerPageChangeListener; private final SlidingTabStrip mTabStrip; public SlidingTabLayout(Context context) { this(context, null); } public SlidingTabLayout(Context context, AttributeSet attrs) { this(context, attrs, 0); } public SlidingTabLayout(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); // Disable the Scroll Bar setHorizontalScrollBarEnabled(false); // Make sure that the Tab Strips fills this View setFillViewport(true); mTitleOffset = (int) (TITLE_OFFSET_DIPS * getResources().getDisplayMetrics().density); mTabStrip = new SlidingTabStrip(context); addView(mTabStrip, LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT); } /** * Set the custom {@link TabColorizer} to be used. * <p/> * If you only require simple custmisation then you can use * {@link #setSelectedIndicatorColors(int...)} to achieve * similar effects. */ public void setCustomTabColorizer(TabColorizer tabColorizer) { mTabStrip.setCustomTabColorizer(tabColorizer); } public void setDistributeEvenly(boolean distributeEvenly) { mDistributeEvenly = distributeEvenly; } /** * Sets the colors to be used for indicating the selected tab. These colors are treated as a * circular array. Providing one color will mean that all tabs are indicated with the same color. */ public void setSelectedIndicatorColors(int... colors) { mSelectedIndicatorColors = colors; mTabStrip.setSelectedIndicatorColors(colors); } private int[] mSelectedIndicatorColors; /** * Set the {@link android.support.v4.view.ViewPager.OnPageChangeListener}. When using {@link SlidingTabLayout} you are * required to set any {@link android.support.v4.view.ViewPager.OnPageChangeListener} through this method. This is so * that the layout can update it's scroll position correctly. * * @see android.support.v4.view.ViewPager#setOnPageChangeListener(android.support.v4.view.ViewPager.OnPageChangeListener) */ public void setOnPageChangeListener(ViewPager.OnPageChangeListener listener) { mViewPagerPageChangeListener = listener; } /** * Set the custom layout to be inflated for the tab views. * * @param layoutResId Layout id to be inflated * @param textViewId id of the {@link TextView} in the inflated view */ public void setCustomTabView(int layoutResId, int textViewId) { mTabViewLayoutId = layoutResId; mTabViewTextViewId = textViewId; } public void setCustomTabView(int layoutResId, OnTabIconListener listener, int tabViewIconId) { this.mTabViewLayoutId = layoutResId; this.mIconListener = listener; this.mTabViewIconId = tabViewIconId; } /** * Sets the associated view pager. Note that the assumption here is that the pager content * (number of tabs and tab titles) does not change after this call has been made. */ public void setViewPager(ViewPager viewPager) { mTabStrip.removeAllViews(); mViewPager = viewPager; if (viewPager != null) { viewPager.setOnPageChangeListener(new InternalViewPagerListener()); populateTabStrip(); } } /** * Create a default view to be used for tabs. This is called if a custom tab view is not set via * {@link #setCustomTabView(int, int)}. */ protected TextView createDefaultTabView(Context context) { TextView textView = new TextView(context); textView.setGravity(Gravity.CENTER); textView.setTextSize(TypedValue.COMPLEX_UNIT_SP, TAB_VIEW_TEXT_SIZE_SP); textView.setTextColor(getResources().getColor(TAB_VIEW_TEXT_COLOR)); textView.setTypeface(Typeface.DEFAULT_BOLD); textView.setLayoutParams(new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT)); TypedValue outValue = new TypedValue(); getContext().getTheme().resolveAttribute(android.R.attr.selectableItemBackground, outValue, true); textView.setBackgroundResource(outValue.resourceId); textView.setAllCaps(true); int padding = (int) (TAB_VIEW_PADDING_DIPS * getResources().getDisplayMetrics().density); textView.setPadding(padding, padding, padding, padding); return textView; } public View getBadgeView(int i) { return mTabStrip.getChildAt(i).findViewById(mTabViewTextViewId); } private void populateTabStrip() { final PagerAdapter adapter = mViewPager.getAdapter(); final OnClickListener tabClickListener = new TabClickListener(); for (int i = 0; i < adapter.getCount(); i++) { View tabView = null; TextView tabTitleView = null; if (mTabViewLayoutId != 0) { // If there is a custom tab view layout id set, try and inflate it tabView = LayoutInflater.from(getContext()).inflate(mTabViewLayoutId, mTabStrip, false); if (mTabViewTextViewId != 0) { tabTitleView = (TextView) tabView.findViewById(mTabViewTextViewId); } } ImageView tabIconView = null; if (mTabViewIconId != 0 && mIconListener != null) { tabIconView = (ImageView) tabView.findViewById(mTabViewIconId); } if (tabView == null) { tabView = createDefaultTabView(getContext()); } if (tabView != null && i == 1) { //mTvMessageCount = (TextView) tabView.findViewById(R.id.tv_unread_count); } if (tabTitleView == null && TextView.class.isInstance(tabView)) { tabTitleView = (TextView) tabView; } if (mDistributeEvenly) { LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams) tabView.getLayoutParams(); lp.width = 0; lp.weight = 1; } if (tabTitleView != null) tabTitleView.setText(adapter.getPageTitle(i)); tabView.setOnClickListener(tabClickListener); String desc = mContentDescriptions.get(i, null); if (desc != null) { tabView.setContentDescription(desc); } if (tabIconView != null) { int icon = mIconListener.getPageIcon(i); if (icon != 0) tabIconView.setImageResource(icon); } mTabStrip.addView(tabView); if (i == mViewPager.getCurrentItem()) { tabView.setSelected(true); if (tabView instanceof TextView) { TextView tv = (TextView) tabView; tv.setTextColor(mTabStrip.getSelectedIndicatorClolor(i)); } } } } private int TAB_VIEW_TEXT_COLOR = R.color.black; public void setDefaultTabTextColor(int color) { TAB_VIEW_TEXT_COLOR = color; } public void setContentDescription(int i, String desc) { mContentDescriptions.put(i, desc); } @Override protected void onAttachedToWindow() { super.onAttachedToWindow(); if (mViewPager != null) { scrollToTab(mViewPager.getCurrentItem(), 0); } } private void scrollToTab(int tabIndex, int positionOffset) { final int tabStripChildCount = mTabStrip.getChildCount(); if (tabStripChildCount == 0 || tabIndex < 0 || tabIndex >= tabStripChildCount) { return; } View selectedChild = mTabStrip.getChildAt(tabIndex); if (selectedChild != null) { int targetScrollX = selectedChild.getLeft() + positionOffset; if (tabIndex > 0 || positionOffset > 0) { // If we're not at the first child and are mid-scroll, make sure we obey the offset targetScrollX -= mTitleOffset; } scrollTo(targetScrollX, 0); } } private class InternalViewPagerListener implements ViewPager.OnPageChangeListener { private int mScrollState; @Override public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) { int tabStripChildCount = mTabStrip.getChildCount(); if ((tabStripChildCount == 0) || (position < 0) || (position >= tabStripChildCount)) { return; } mTabStrip.onViewPagerPageChanged(position, positionOffset); View selectedTitle = mTabStrip.getChildAt(position); int extraOffset = (selectedTitle != null) ? (int) (positionOffset * selectedTitle.getWidth()) : 0; scrollToTab(position, extraOffset); if (mViewPagerPageChangeListener != null) { mViewPagerPageChangeListener.onPageScrolled(position, positionOffset, positionOffsetPixels); } } @Override public void onPageScrollStateChanged(int state) { mScrollState = state; if (mViewPagerPageChangeListener != null) { mViewPagerPageChangeListener.onPageScrollStateChanged(state); } } @Override public void onPageSelected(int position) { if (mScrollState == ViewPager.SCROLL_STATE_IDLE) { mTabStrip.onViewPagerPageChanged(position, 0f); scrollToTab(position, 0); } for (int i = 0; i < mTabStrip.getChildCount(); i++) { View tabView = mTabStrip.getChildAt(i); tabView.setSelected(position == i); if (tabView instanceof TextView) { TextView tv = (TextView) tabView; if (position == i) { tv.setTextColor(mTabStrip.getSelectedIndicatorClolor(i)); } else tv.setTextColor(getResources().getColor(TAB_VIEW_TEXT_COLOR)); } } if (mViewPagerPageChangeListener != null) { mViewPagerPageChangeListener.onPageSelected(position); } } } public void setMessageCount(int i, int count) { if (mTabStrip.getChildAt(i) == null) return; TextView mTvMessageCount = (TextView) mTabStrip.getChildAt(i).findViewById(R.id.tv_unread_count); if (mTvMessageCount == null) return; if (count == 0) { mTvMessageCount.setVisibility(View.GONE); } else { mTvMessageCount.setVisibility(View.VISIBLE); String countStr; if (count < 100) countStr = String.valueOf(count); else { countStr = "99+"; } mTvMessageCount.setText(countStr); } } public void setMessageTipVisible(int visible) { int size = mTabStrip.getChildCount(); for (int i = 0; i < size; i++) { TextView mTvMessageCount = (TextView) mTabStrip.getChildAt(i).findViewById(R.id.tv_unread_count); if (mTvMessageCount == null) continue; if (visible == View.VISIBLE) {// try to show num String count = mTvMessageCount.getText().toString(); if (!TextUtils.isEmpty(count)) { int num = Integer.parseInt(count); if (num > 0) { mTvMessageCount.setVisibility(View.VISIBLE); continue; } } mTvMessageCount.setVisibility(View.INVISIBLE); } else { mTvMessageCount.setVisibility(visible); } } } private class TabClickListener implements OnClickListener { @Override public void onClick(View v) { for (int i = 0; i < mTabStrip.getChildCount(); i++) { if (v == mTabStrip.getChildAt(i)) { mViewPager.setCurrentItem(i); return; } } } } }