getScaledTouchSlop是一个距离，表示滑动的时候，手的移动要大于这个距离才开始移动控件。如果小于这个距离就不触发移动控件，如viewpager就是用这个距离来判断用户是否翻页
ViewConfiguration滑动参数设置类：
/** * 包含了方法和标准的常量用来设置UI的超时、大小和距离 */ public class ViewConfiguration { // 设定水平滚动条的宽度和垂直滚动条的高度，单位是像素px private static final int SCROLL_BAR_SIZE = 10; //定义滚动条逐渐消失的时间，单位是毫秒 private static final int SCROLL_BAR_FADE_DURATION = 250; // 默认的滚动条多少秒之后消失，单位是毫秒 private static final int SCROLL_BAR_DEFAULT_DELAY = 300; // 定义边缘地方褪色的长度 private static final int FADING_EDGE_LENGTH = 12; //定义子控件按下状态的持续事件 private static final int PRESSED_STATE_DURATION = 125; //定义一个按下状态转变成长按状态的转变时间 private static final int LONG_PRESS_TIMEOUT = 500; //定义用户在按住适当按钮，弹出全局的对话框的持续时间 private static final int GLOBAL_ACTIONS_KEY_TIMEOUT = 500; //定义一个touch事件中是点击事件还是一个滑动事件所需的时间，如果用户在这个时间之内滑动，那么就认为是一个点击事件 private static final int TAP_TIMEOUT = 115; /** * Defines the duration in milliseconds we will wait to see if a touch event * is a jump tap. If the user does not complete the jump tap within this interval, it is * considered to be a tap. */ //定义一个touch事件时候是一个点击事件。如果用户在这个时间内没有完成这个点击，那么就认为是一个点击事件 private static final int JUMP_TAP_TIMEOUT = 500; //定义双击事件的间隔时间 private static final int DOUBLE_TAP_TIMEOUT = 300; //定义一个缩放控制反馈到用户界面的时间 private static final int ZOOM_CONTROLS_TIMEOUT = 3000; /** * Inset in pixels to look for touchable content when the user touches the edge of the screen */ private static final int EDGE_SLOP = 12; /** * Distance a touch can wander before we think the user is scrolling in pixels */ private static final int TOUCH_SLOP = 16; /** * Distance a touch can wander before we think the user is attempting a paged scroll * (in dips) */ private static final int PAGING_TOUCH_SLOP = TOUCH_SLOP * 2; /** * Distance between the first touch and second touch to still be considered a double tap */ private static final int DOUBLE_TAP_SLOP = 100; /** * Distance a touch needs to be outside of a window's bounds for it to * count as outside for purposes of dismissing the window. */ private static final int WINDOW_TOUCH_SLOP = 16; //用来初始化fling的最小速度，单位是每秒多少像素 private static final int MINIMUM_FLING_VELOCITY = 50; //用来初始化fling的最大速度，单位是每秒多少像素 private static final int MAXIMUM_FLING_VELOCITY = 4000; //视图绘图缓存的最大尺寸，以字节表示。在ARGB888格式下，这个尺寸应至少等于屏幕的大小 @Deprecated private static final int MAXIMUM_DRAWING_CACHE_SIZE = 320 * 480 * 4; // HVGA screen, ARGB8888 //flings和scrolls摩擦力度大小的系数 private static float SCROLL_FRICTION = 0.015f; /** * Max distance to over scroll for edge effects */ private static final int OVERSCROLL_DISTANCE = 0; /** * Max distance to over fling for edge effects */ private static final int OVERFLING_DISTANCE = 4; }