Android自定义ViewPager实例
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2024-02-20 15:12:10
本文实例讲述了android自定义viewpager的方法。分享给大家供大家参考,具体如下:
package com.rong.activity;
import...
本文实例讲述了android自定义viewpager的方法。分享给大家供大家参考,具体如下:
package com.rong.activity; import android.content.context; import android.graphics.color; import android.util.attributeset; import android.view.motionevent; import android.view.velocitytracker; import android.view.view; import android.view.viewgroup; import android.widget.linearlayout; import android.widget.scroller; public class customviewpager extends viewgroup { private context mcontext; private int screenwidth; private int screenhight; private int lastmovex = 0; private velocitytracker velocitytracker; private int max_velocity=600; private int curscreen=0; private scroller scroller; public customviewpager(context context) { super(context); mcontext = context; initview(); } public customviewpager(context context, attributeset attrs) { super(context, attrs); mcontext = context; initview(); } public customviewpager(context context, attributeset attrs, int defstyle) { super(context, attrs, defstyle); mcontext = context; initview(); } @override public boolean ontouchevent(motionevent event) { if (velocitytracker == null) { velocitytracker = velocitytracker.obtain(); } velocitytracker.addmovement(event); int x = (int) event.getx(); switch (event.getaction()) { case motionevent.action_down: lastmovex = x; break; case motionevent.action_move: int dis = lastmovex - x; scrollby(dis, 0); lastmovex = x; break; case motionevent.action_up: velocitytracker.computecurrentvelocity(1000); int velocityx=(int)velocitytracker.getxvelocity(); if(velocityx>max_velocity&&curscreen>0){ jump2screen(curscreen-1); }else if(velocityx<-max_velocity&&curscreen<getchildcount()-1){ jump2screen(curscreen+1); }else{ int screen=(getscrollx()+screenwidth/2)/screenwidth; jump2screen(screen); } if (velocitytracker != null) { velocitytracker.recycle(); velocitytracker = null; } break; } return true; } /** * 跳转到指定screen * @param screen */ public void jump2screen(int screen){ curscreen=screen; if(curscreen>getchildcount()-1){ curscreen=getchildcount()-1; } int dis=curscreen*screenwidth-getscrollx(); scroller.startscroll(getscrollx(), 0, dis, 0); invalidate(); } @override public void computescroll() { if(scroller.computescrolloffset()){ scrollto(scroller.getcurrx(), 0); postinvalidate(); } } public void initview() { scroller=new scroller(mcontext); linearlayout layout1 = new linearlayout(getcontext()); layout1.setbackgroundcolor(color.red); addview(layout1); linearlayout layout2 = new linearlayout(getcontext()); layout2.setbackgroundcolor(color.green); addview(layout2); linearlayout layout3 = new linearlayout(getcontext()); layout3.setbackgroundcolor(color.blue); addview(layout3); } @override protected void onmeasure(int widthmeasurespec, int heightmeasurespec) { super.onmeasure(widthmeasurespec, heightmeasurespec); screenwidth = measurespec.getsize(widthmeasurespec); screenhight = measurespec.getsize(heightmeasurespec); setmeasureddimension(screenwidth, screenhight); for (int i = 0; i < getchildcount(); i++) { view view = getchildat(i); view.measure(screenwidth, screenhight); } } @override protected void onlayout(boolean changed, int l, int t, int r, int b) { int leftwidth = 0; for (int i = 0; i < getchildcount(); i++) { view view = getchildat(i); view.layout(leftwidth, 0, leftwidth + screenwidth, screenhight); leftwidth = leftwidth + screenwidth; } } }
更多关于android相关内容感兴趣的读者可查看本站专题:《android开发入门与进阶教程》、《android基本组件用法总结》、《android视图view技巧总结》、《android布局layout技巧总结》及《android控件用法总结》
希望本文所述对大家android程序设计有所帮助。
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