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;
}
};
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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;
}
};
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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。