说起在android上要实现类似launch的抽屉效果，大家一定首先会想起slidingdrawer。slidingdrawer是android官方控件之一，但是本文的主角并不是它，而是民间的控件工具集合：android-misc-widgets。android-misc-widgets里面包含几个widget：panel、smoothbutton、switcher、virtualkeyboard,还有一些动画特效，本文主要介绍抽屉容器panel的用法。android-misc-widgets的google工程地址：-widgets/http://code.google.com/p/android-misc。
工程代码中panel的演示效果如下所示：
这个panel控件可以轻易实现不同方向的抽屉效果，比slidingdrawer有更强的扩展性！
在多次使用panel的过程中，发现panel有个bug，会间断性出现“闪烁”，也就是在ontouchlistener里面的触发action_down后，抽屉瞬间弹出然后瞬间回收(版本日期为feb 3, 2009)。把原panel的ontouchlistener加以替换，即以下代码：
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ontouchlistener touchlistener = new ontouchlistener() { int initx; int inity; boolean setinitialposition; public boolean ontouch(view v, motionevent event) { if (mstate == state.animating) { // we are animating return false; }// log.d(tag, "state: " + mstate + " x: " + event.getx() + " y: " + event.gety()); int action = event.getaction(); if (action == motionevent.action_down) { if (mbringtofront) { bringtofront(); } initx = 0; inity = 0; if (mcontent.getvisibility() == gone) { // since we may not know content dimensions we use factors here if (morientation == vertical) { inity = mposition == top? -1 : 1; } else { initx = mposition == left? -1 : 1; } } setinitialposition = true; } else { if (setinitialposition) { // now we know content dimensions, so we multiply factors... initx *= mcontentwidth; inity *= mcontentheight; // ... and set initial panel's position mgesturelistener.setscroll(initx, inity); setinitialposition = false; // for offsetlocation we have to invert values initx = -initx; inity = -inity; } // offset every action_move & action_up event event.offsetlocation(initx, inity); } if (!mgesturedetector.ontouchevent(event)) { if (action == motionevent.action_up) { // tup up after scrolling post(startanimation); } } return false; }}; |
替换为：
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ontouchlistener touchlistener = new ontouchlistener() { float touchx, touchy; public boolean ontouch(view v, motionevent event) { if (mstate == state.animating) { // we are animating return false; } int action = event.getaction(); if (action == motionevent.action_down) { if (mbringtofront) { bringtofront(); } touchx = event.getx(); touchy = event.gety(); } if (!mgesturedetector.ontouchevent(event)) { if (action == motionevent.action_up) { // tup up after scrolling int size = (int) (math.abs(touchx - event.getx()) + math .abs(touchy - event.gety())); if (size == mcontentwidth || size == mcontentheight) { mstate = state.about_to_animate; //log.e("size", string.valueof(size)); //log.e(string.valueof(mcontentwidth),string.valueof(mcontentheight)); } post(startanimation); } } return false; }}; |
即可修复这个bug，并且也同样实现了onclicklistener的功能，可以把原panel的onclicklistener给删掉了！
希望本文所述实例对于大家进行android项目开发能有所帮助。
