/*
* Copyright (C) 2013 Peng fei Pan <sky@xiaopan.me>
*
* 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.tekinarslan.material.sample.customui;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.drawable.Drawable;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
import android.widget.HorizontalScrollView;
import android.widget.LinearLayout;
import com.tekinarslan.material.sample.R;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
/**
* 专为ViewPager定制的滑动选项卡 HOME
*
* @version 1.3.0
* @author Peng fei Pan
*/
public class PagerSlidingTabStrip extends HorizontalScrollView implements
View.OnClickListener {
private int currentPosition; // 当前位置
private int lastOffset;
private int lastScrollX = 0;
private float currentPositionOffset; // 当前位置偏移量
private boolean start;
private boolean allowWidthFull; // 内容宽度无法充满时，允许自动调整Item的宽度以充满
private boolean disableViewPager; // 禁用ViewPager
private View currentSelectedTabView; // 当前标题项
private Drawable slidingBlockDrawable; // 滑块
private ViewPager viewPager; // ViewPager
private ViewGroup tabsLayout; // 标题项布局
private ViewPager.OnPageChangeListener onPageChangeListener; // 页面改变监听器
private OnClickTabListener onClickTabListener;
private OnPagerChangeLis listener;
private List<View> tabViews;
public PagerSlidingTabStrip(Context context) {
this(context, null);
}
public PagerSlidingTabStrip(Context context, AttributeSet attrs) {
super(context, attrs);
setHorizontalScrollBarEnabled(false); // 隐藏横向滑动提示条
if (attrs != null) {
TypedArray attrsTypedArray = context.obtainStyledAttributes(attrs,
R.styleable.PagerSlidingTabStrip);
if (attrsTypedArray != null) {
allowWidthFull = attrsTypedArray.getBoolean(
R.styleable.PagerSlidingTabStrip_allowWidthFull, false);
slidingBlockDrawable = attrsTypedArray
.getDrawable(R.styleable.PagerSlidingTabStrip_slidingBlock);
disableViewPager = attrsTypedArray.getBoolean(
R.styleable.PagerSlidingTabStrip_disableViewPager,
false);
attrsTypedArray.recycle();
}
}
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
if (!allowWidthFull)
return;
ViewGroup tabsLayout = getTabsLayout();
if (tabsLayout == null
|| tabsLayout.getMeasuredWidth() >= getMeasuredWidth())
return;
if (tabsLayout.getChildCount() <= 0)
return;
if (tabViews == null) {
tabViews = new ArrayList<View>();
} else {
tabViews.clear();
}
for (int w = 0; w < tabsLayout.getChildCount(); w++) {
tabViews.add(tabsLayout.getChildAt(w));
}
adjustChildWidthWithParent(
tabViews,
getMeasuredWidth() - tabsLayout.getPaddingLeft()
- tabsLayout.getPaddingRight(), widthMeasureSpec,
heightMeasureSpec);
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
/**
* 调整views集合中的View，让所有View的宽度加起来正好等于parentViewWidth
*
* @param views
* 子View集合
* @param parentViewWidth
* 父Vie的宽度
* @param parentWidthMeasureSpec
* 父View的宽度规则
* @param parentHeightMeasureSpec
* 父View的高度规则
*/
private void adjustChildWidthWithParent(List<View> views,
int parentViewWidth, int parentWidthMeasureSpec,
int parentHeightMeasureSpec) {
// 先去掉所有子View的外边距
for (View view : views) {
if (view.getLayoutParams() instanceof MarginLayoutParams) {
LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams) view
.getLayoutParams();
parentViewWidth -= lp.leftMargin + lp.rightMargin;
}
}
// 去掉宽度大于平均宽度的View后再次计算平均宽度
int averageWidth = parentViewWidth / views.size();
int bigTabCount = views.size();
while (true) {
Iterator<View> iterator = views.iterator();
while (iterator.hasNext()) {
View view = iterator.next();
if (view.getMeasuredWidth() > averageWidth) {
parentViewWidth -= view.getMeasuredWidth();
bigTabCount--;
iterator.remove();
}
}
averageWidth = parentViewWidth / bigTabCount;
boolean end = true;
for (View view : views) {
if (view.getMeasuredWidth() > averageWidth) {
end = false;
}
}
if (end) {
break;
}
}
// 修改宽度小于新的平均宽度的View的宽度
for (View view : views) {
if (view.getMeasuredWidth() < averageWidth) {
LinearLayout.LayoutParams layoutParams = (LinearLayout.LayoutParams) view
.getLayoutParams();
layoutParams.width = averageWidth;
view.setLayoutParams(layoutParams);
// 再次测量让新宽度生效
if (layoutParams instanceof MarginLayoutParams) {
measureChildWithMargins(view, parentWidthMeasureSpec, 0,
parentHeightMeasureSpec, 0);
} else {
measureChild(view, parentWidthMeasureSpec,
parentHeightMeasureSpec);
}
}
}
}
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
super.onLayout(changed, l, t, r, b);
ViewGroup tabViewGroup = getTabsLayout();
if (tabViewGroup != null) {
// 初始化滑块位置以及选中状态
currentPosition = viewPager != null ? viewPager.getCurrentItem()
: 0;
if (!disableViewPager) {
scrollToChild(currentPosition, 0); // 移动滑块到指定位置
selectedTab(currentPosition); // 选中指定位置的TAB
}
// 给每一个tab设置点击事件，当点击的时候切换Pager
for (int w = 0; w < tabViewGroup.getChildCount(); w++) {
View itemView = tabViewGroup.getChildAt(w);
itemView.setTag(w);
itemView.setOnClickListener(this);
}
}
}
@Override
public void onClick(View v) {
int index = (Integer) v.getTag();
if (onClickTabListener != null) {
onClickTabListener.onClickTab(v, index);
}
if (viewPager != null) {
viewPager.setCurrentItem(index, true);
}
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (disableViewPager)
return;
/* 绘制滑块 */
ViewGroup tabsLayout = getTabsLayout();
if (tabsLayout != null && tabsLayout.getChildCount() > 0
&& slidingBlockDrawable != null) {
View currentTab = tabsLayout.getChildAt(currentPosition);
if (currentTab != null) {
float slidingBlockLeft = currentTab.getLeft();
float slidingBlockRight = currentTab.getRight();
if (currentPositionOffset > 0f
&& currentPosition < tabsLayout.getChildCount() - 1) {
View nextTab = tabsLayout.getChildAt(currentPosition + 1);
if (nextTab != null) {
final float nextTabLeft = nextTab.getLeft();
final float nextTabRight = nextTab.getRight();
slidingBlockLeft = (currentPositionOffset * nextTabLeft + (1f - currentPositionOffset)
* slidingBlockLeft);
slidingBlockRight = (currentPositionOffset
* nextTabRight + (1f - currentPositionOffset)
* slidingBlockRight);
}
}
slidingBlockDrawable.setBounds((int) slidingBlockLeft, 0,
(int) slidingBlockRight, getHeight());
slidingBlockDrawable.draw(canvas);
}
}
}
/**
* 获取布局
*/
private ViewGroup getTabsLayout() {
if (tabsLayout == null) {
if (getChildCount() > 0) {
tabsLayout = (ViewGroup) getChildAt(0);
} else {
removeAllViews();
tabsLayout = new LinearLayout(getContext());
addView(tabsLayout, new ViewGroup.LayoutParams(
ViewGroup.LayoutParams.WRAP_CONTENT,
ViewGroup.LayoutParams.WRAP_CONTENT));
}
}
return tabsLayout;
}
/**
* 滚动到指定的位置
*/
private void scrollToChild(int position, int offset) {
ViewGroup tabsLayout = getTabsLayout();
if (tabsLayout != null && tabsLayout.getChildCount() > 0
&& position < tabsLayout.getChildCount()) {
View view = tabsLayout.getChildAt(position);
if (view != null) {
// 计算新的X坐标
int newScrollX = view.getLeft() + offset;
if (position > 0 || offset > 0) {
newScrollX -= 240 - getOffset(view.getWidth()) / 2;
}
// 如果同上次X坐标不一样就执行滚动
if (newScrollX != lastScrollX) {
lastScrollX = newScrollX;
scrollTo(newScrollX, 0);
}
}
}
}
/**
* 获取偏移量
*/
private int getOffset(int newOffset) {
if (lastOffset < newOffset) {
if (start) {
lastOffset += 1;
return lastOffset;
} else {
start = true;
lastOffset += 1;
return lastOffset;
}
}
if (lastOffset > newOffset) {
if (start) {
lastOffset -= 1;
return lastOffset;
} else {
start = true;
lastOffset -= 1;
return lastOffset;
}
} else {
start = true;
lastOffset = newOffset;
return lastOffset;
}
}
/**
* 选中指定位置的TAB
*/
private void selectedTab(int currentSelectedTabPosition) {
ViewGroup tabsLayout = getTabsLayout();
if (currentSelectedTabPosition > -1 && tabsLayout != null
&& currentSelectedTabPosition < tabsLayout.getChildCount()) {
if (currentSelectedTabView != null) {
currentSelectedTabView.setSelected(false);
}
currentSelectedTabView = tabsLayout
.getChildAt(currentSelectedTabPosition);
if (currentSelectedTabView != null) {
currentSelectedTabView.setSelected(true);
}
}
}
/**
* 添加Tab
*/
public void addTab(View tabView, int index) {
if (tabView != null) {
getTabsLayout().addView(tabView, index);
requestLayout();
}
}
/**
* 添加Tab
*/
public void addTab(View tabView) {
addTab(tabView, -1);
}
/**
* 添加Tab
*
* @param tabViews
* 可以一次添加多个Tab
*/
public void addTab(View... tabViews) {
if (tabViews != null) {
for (View view : tabViews) {
getTabsLayout().addView(view);
}
requestLayout();
}
}
/**
* 添加Tab
*/
public void addTab(List<View> tabViews) {
if (tabViews != null) {
for (View view : tabViews) {
getTabsLayout().addView(view);
}
requestLayout();
}
}
/**
* 移除一个tab
*
* @param index
*/
public void removeTab(int index) {
removeTab(index, 1);
}
/**
* 移除tab
*
* @param start 开始位置
* @param count 移除的数量
*/
public void removeTab(int start, int count) {
int tabCount = getTabCount();
if (start < 0 || start > tabCount) {
start = 0;
}
if (count < 0 || count > tabCount) {
count = 1;
}
if (count - start > tabCount) {
count = tabCount - start;
}
getTabsLayout().removeViews(start, count);
requestLayout();
}
/**
* 移除所有
*/
public void removeAllTab() {
getTabsLayout().removeAllViews();
requestLayout();
}
public View getChild(int idx) {
return getTabsLayout().getChildAt(idx);
}
public View getBadgeView(int i) {
return getTabsLayout().getChildAt(i).findViewById(R.id.tab_mes);
}
/**
* 设置ViewPager
*
* @param viewPager
* ViewPager
*/
public void setViewPager(ViewPager viewPager) {
if (disableViewPager)
return;
this.viewPager = viewPager;
this.viewPager.setOnPageChangeListener(new OnPageChangeListener() {
@Override
public void onPageSelected(int position) {
selectedTab(position);
if (onPageChangeListener != null) {
onPageChangeListener.onPageSelected(position);
}
if (listener != null)
listener.onChanged(position);
}
@Override
public void onPageScrolled(int nextPagePosition,
float positionOffset, int positionOffsetPixels) {
ViewGroup tabsLayout = getTabsLayout();
if (nextPagePosition < tabsLayout.getChildCount()) {
View view = tabsLayout.getChildAt(nextPagePosition);
if (view != null) {
currentPosition = nextPagePosition;
currentPositionOffset = positionOffset;
scrollToChild(nextPagePosition,
(int) (positionOffset * view.getWidth()));
invalidate();
}
}
if (onPageChangeListener != null) {
onPageChangeListener.onPageScrolled(nextPagePosition,
positionOffset, positionOffsetPixels);
}
}
@Override
public void onPageScrollStateChanged(int arg0) {
if (onPageChangeListener != null) {
onPageChangeListener.onPageScrollStateChanged(arg0);
}
}
});
requestLayout();
}
/**
* 设置Page切换监听器
*
* @param onPageChangeListener
* Page切换监听器
*/
public void setOnPageChangeListener(
OnPageChangeListener onPageChangeListener) {
this.onPageChangeListener = onPageChangeListener;
}
/**
* 设置是否充满屏幕
*
* @param allowWidthFull
* true：当内容的宽度无法充满屏幕时，自动调整每一个Item的宽度以充满屏幕
*/
public void setAllowWidthFull(boolean allowWidthFull) {
this.allowWidthFull = allowWidthFull;
requestLayout();
}
/**
* 设置滑块图片
*/
public void setSlidingBlockDrawable(Drawable slidingBlockDrawable) {
this.slidingBlockDrawable = slidingBlockDrawable;
requestLayout();
}
/**
* 获取Tab总数
*/
public int getTabCount() {
ViewGroup tabsLayout = getTabsLayout();
return tabsLayout != null ? tabsLayout.getChildCount() : 0;
}
/**
* 设置Tab点击监听器
*
* @param onClickTabListener
* Tab点击监听器
*/
public void setOnClickTabListener(OnClickTabListener onClickTabListener) {
this.onClickTabListener = onClickTabListener;
}
/**
* 设置不使用ViewPager
*
* @param disableViewPager
* 不使用ViewPager
*/
public void setDisableViewPager(boolean disableViewPager) {
this.disableViewPager = disableViewPager;
if (viewPager != null) {
viewPager.setOnPageChangeListener(onPageChangeListener);
viewPager = null;
}
requestLayout();
}
/**
* Tab点击监听器
*
* @author xiaopan
*
*/
public interface OnClickTabListener {
public void onClickTab(View tab, int index);
}
public void setOnPagerChange(OnPagerChangeLis l) {
this.listener = l;
}
public interface OnPagerChangeLis {
void onChanged(int page);
}
}