com.machine.custom.viewpagerindicator.TabUnderlinePageIndicator.java Source code

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Here is the source code for com.machine.custom.viewpagerindicator.TabUnderlinePageIndicator.java

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/*
 * Copyright (C) 2011 The Android Open Source Project
 * Copyright (C) 2011 Jake Wharton
 *
 * 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.machine.custom.viewpagerindicator;

import static android.view.ViewGroup.LayoutParams.MATCH_PARENT;
import static android.view.ViewGroup.LayoutParams.WRAP_CONTENT;

//import com.android.overlay.utils.LogUtils;
import com.machine.watching.R;

import android.annotation.SuppressLint;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Paint.Style;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.widget.HorizontalScrollView;
import android.widget.LinearLayout;
import android.widget.TextView;

/**
 * This widget implements the dynamic action bar tab behavior that can change
 * across different configurations or circumstances.
 */
public class TabUnderlinePageIndicator extends HorizontalScrollView implements PageIndicator {
    /** Title text used when no title is provided by the adapter. */
    private static final CharSequence EMPTY_TITLE = "";

    /**
     * Interface for a callback when the selected tab has been reselected.
     */
    public interface OnTabReselectedListener {
        /**
         * Callback when the selected tab has been reselected.
         *
         * @param position Position of the current center item.
         */
        void onTabReselected(int position);
    }

    public interface OnTabCollListener {
        /**
         * coll_dir 0 1 2?
         */
        void OnTabColl(int coll_dir);
    }

    private Runnable mTabSelector;

    private OnTabCollListener onTabCollListener;

    private final OnClickListener mTabClickListener = new OnClickListener() {
        public void onClick(View view) {
            TabView tabView = (TabView) view;
            final int oldSelected = mViewPager.getCurrentItem();
            final int newSelected = tabView.getIndex();
            //            LogUtils.d("TUPI", "onClick:" + newSelected);
            mViewPager.setCurrentItem(newSelected);
            if (oldSelected == newSelected && mTabReselectedListener != null) {
                mTabReselectedListener.onTabReselected(newSelected);
            }
        }
    };

    private final IcsLinearLayout mTabLayout;

    private ViewPager mViewPager;
    private ViewPager.OnPageChangeListener mListener;

    private int mMaxTabWidth;
    private int mSelectedTabIndex;

    private OnTabReselectedListener mTabReselectedListener;

    private Paint rectPaint;
    private int currentPosition = 0;
    private float currentPositionOffset = 0f;
    private int indicatorHeight = 6;
    private int underlineColor = Color.parseColor("#5677fc");

    public TabUnderlinePageIndicator(Context context) {
        this(context, null);
    }

    public TabUnderlinePageIndicator(Context context, AttributeSet attrs) {
        super(context, attrs);
        setHorizontalScrollBarEnabled(false);

        rectPaint = new Paint();
        rectPaint.setAntiAlias(true);
        rectPaint.setStyle(Style.FILL);

        mTabLayout = new IcsLinearLayout(context, R.attr.vpiTabUnderlinePageIndicatorStyle);
        addView(mTabLayout, new ViewGroup.LayoutParams(WRAP_CONTENT, MATCH_PARENT));
    }

    public void setUnderlineColor(int underlineColor) {
        this.underlineColor = underlineColor;
        invalidate();
    }

    public void setIndicatorHeight(int indicatorLineHeightPx) {
        this.indicatorHeight = indicatorLineHeightPx;
        invalidate();
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);

        final int childCount = mTabLayout.getChildCount();
        if (isInEditMode() || childCount == 0) {
            return;
        }

        final int height = getHeight();

        // draw indicator line

        rectPaint.setColor(underlineColor);

        // default: line below current tab
        View currentTab = mTabLayout.getChildAt(currentPosition);
        float lineLeft = currentTab.getLeft();
        float lineRight = currentTab.getRight();

        // if there is an offset, start interpolating left and right coordinates between current and next tab
        if (currentPositionOffset > 0f && currentPosition < childCount - 1) {

            View nextTab = mTabLayout.getChildAt(currentPosition + 1);
            final float nextTabLeft = nextTab.getLeft();
            final float nextTabRight = nextTab.getRight();

            lineLeft = (currentPositionOffset * nextTabLeft + (1f - currentPositionOffset) * lineLeft);
            lineRight = (currentPositionOffset * nextTabRight + (1f - currentPositionOffset) * lineRight);
        }

        canvas.drawRect(lineLeft, height - indicatorHeight, lineRight, height, rectPaint);

    }

    public void setOnTabCollListener(OnTabCollListener onTabCollListener) {
        this.onTabCollListener = onTabCollListener;
    }

    public void setOnTabReselectedListener(OnTabReselectedListener listener) {
        mTabReselectedListener = listener;
    }

    @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;
        }
        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.
            setCurrentItem(mSelectedTabIndex);
        }
    }

    private 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;
                if (onTabCollListener != null) {
                    if (scrollPos >= mMaxTabWidth) {
                        onTabCollListener.OnTabColl(2);
                    } else if (scrollPos <= 0) {
                        onTabCollListener.OnTabColl(1);
                    } else {
                        onTabCollListener.OnTabColl(0);
                    }
                }
            }
        };
        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 void addTab(int index, CharSequence text, int iconResId) {
        final TabView tabView = new TabView(getContext());
        tabView.mIndex = index;
        tabView.setFocusable(true);
        tabView.setOnClickListener(mTabClickListener);
        tabView.setText(text);
        //tabView.setTextSize(16);
        //tabView.setTextColor(getContext().getResources().getColor(R.color.news_text_title_color));
        tabView.setSingleLine();
        if (iconResId != 0) {
            tabView.setCompoundDrawablesWithIntrinsicBounds(iconResId, 0, 0, 0);
        }

        mTabLayout.addView(tabView, new LinearLayout.LayoutParams(0, MATCH_PARENT, 1));
    }

    @Override
    public void onPageScrollStateChanged(int arg0) {
        //       LogUtils.d("TUPI", "onPageScrollStateChanged:" + arg0);
        if (mListener != null) {
            mListener.onPageScrollStateChanged(arg0);
        }
    }

    @Override
    public void onPageScrolled(int arg0, float arg1, int arg2) {
        //       LogUtils.d("TUPI", "onPageScrolled:" + arg0 + "[" + arg1 + "]");
        currentPosition = arg0;
        currentPositionOffset = arg1;
        invalidate();
        if (mListener != null) {
            mListener.onPageScrolled(arg0, arg1, arg2);
        }
    }

    @Override
    public void onPageSelected(int arg0) {
        //       LogUtils.d("TUPI", "onPageSelected:" + arg0);
        setCurrentItem(arg0);
        if (mListener != null) {
            mListener.onPageSelected(arg0);
        }
    }

    @Override
    public void setViewPager(ViewPager view) {
        if (mViewPager == view) {
            return;
        }
        if (mViewPager != null) {
            mViewPager.setOnPageChangeListener(null);
        }
        final PagerAdapter adapter = view.getAdapter();
        if (adapter == null) {
            throw new IllegalStateException("ViewPager does not have adapter instance.");
        }
        mViewPager = view;
        view.setOnPageChangeListener(this);
        notifyDataSetChanged();
    }

    public void notifyDataSetChanged() {
        mTabLayout.removeAllViews();
        PagerAdapter adapter = mViewPager.getAdapter();
        IconPagerAdapter iconAdapter = null;
        if (adapter instanceof IconPagerAdapter) {
            iconAdapter = (IconPagerAdapter) adapter;
        }
        final int count = adapter.getCount();
        for (int i = 0; i < count; i++) {
            CharSequence title = adapter.getPageTitle(i);
            if (title == null) {
                title = EMPTY_TITLE;
            }
            int iconResId = 0;
            if (iconAdapter != null) {
                iconResId = iconAdapter.getIconResId(i);
            }
            addTab(i, title, iconResId);
        }
        if (mSelectedTabIndex > count) {
            mSelectedTabIndex = count - 1;
        }
        setCurrentItem(mSelectedTabIndex);
        requestLayout();
    }

    @Override
    public void setViewPager(ViewPager view, int initialPosition) {
        setViewPager(view);
        setCurrentItem(initialPosition);
    }

    @Override
    public void setCurrentItem(int item) {
        if (mViewPager == null) {
            throw new IllegalStateException("ViewPager has not been bound.");
        }
        mSelectedTabIndex = item;
        //        currentPosition = mSelectedTabIndex;
        mViewPager.setCurrentItem(item);

        final int tabCount = mTabLayout.getChildCount();
        for (int i = 0; i < tabCount; i++) {
            final View child = mTabLayout.getChildAt(i);
            final boolean isSelected = (i == item);
            child.setSelected(isSelected);
            if (isSelected) {
                animateToTab(item);
            }
        }
    }

    @Override
    public void setOnPageChangeListener(OnPageChangeListener listener) {
        mListener = listener;
    }

    private class TabView extends TextView {
        private int mIndex;

        public TabView(Context context) {
            super(context, null, R.attr.vpiTabUnderlinePageIndicatorStyle);
        }

        @Override
        public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
            super.onMeasure(widthMeasureSpec, heightMeasureSpec);
            // beacuse no Limit the width , so annotation code.
            // Re-measure if we went beyond our maximum size.
            //            if (mMaxTabWidth > 0 && getMeasuredWidth() > mMaxTabWidth) {
            //                super.onMeasure(MeasureSpec.makeMeasureSpec(mMaxTabWidth, MeasureSpec.EXACTLY),
            //                        heightMeasureSpec);
            //            }
        }

        public int getIndex() {
            return mIndex;
        }
    }

    float last_x = 0;

    @SuppressLint("ClickableViewAccessibility")
    @Override
    public boolean onTouchEvent(MotionEvent ev) {

        int action = ev.getAction();
        switch (action) {
        case MotionEvent.ACTION_MOVE:
            float x = getScrollX();
            if (onTabCollListener != null) {
                if (x <= 0) {
                    onTabCollListener.OnTabColl(1);
                } else if (x == last_x) {
                    onTabCollListener.OnTabColl(2);
                } else {
                    onTabCollListener.OnTabColl(0);
                }
            }
            last_x = x;
            break;
        case MotionEvent.ACTION_UP:
            last_x = 0;
            break;
        }
        return super.onTouchEvent(ev);
    }

}