package com.aohanyao.viewpager;

/**
 * Copyright (C) 2015 Kaelaela
 * <p>
 * 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
 * <p>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p>
 * 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.
 */

import android.content.Context;
import android.support.v4.view.ViewPager;
import android.util.AttributeSet;
import android.view.MotionEvent;

/**
 * 垂直方向的ViewPager
 */
public class VerticalViewPager extends ViewPager {

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

    public VerticalViewPager(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    private MotionEvent swapTouchEvent(MotionEvent event) {
        float width = getWidth();
        float height = getHeight();

        float swappedX = (event.getY() / height) * width;
        float swappedY = (event.getX() / width) * height;

        event.setLocation(swappedX, swappedY);

        return event;
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent event) {
        boolean intercept = super.onInterceptTouchEvent(swapTouchEvent(event));
        //If not intercept, touch event should not be swapped.
        swapTouchEvent(event);
        return intercept;
    }

    @Override
    public boolean onTouchEvent(MotionEvent ev) {
        return super.onTouchEvent(swapTouchEvent(ev));
    }

}