1、android点两次返回键退出程序
/**
* 退出时间
*/
private
long mExitTime;
/**
* 退出间隔
*/
private
static
final
int
INTERVAL = 2000;
/**
* 判断两次返回时间间隔,小于两秒则退出程序
*/
private
void exit() {
if (System.
currentTimeMillis() - mExitTime >
INTERVAL) {
Toast.
makeText(
this, "再按一次返回键,可直接退出程序", Toast.
LENGTH_SHORT).show();
mExitTime = System.
currentTimeMillis();
}
else {
finish();
android.os.Process.
killProcess(android.os.Process.
myPid());
System.
exit(0);
}
}
2、addView 并控制其位置和大小及层次
- RelativeLayout.LayoutParams lp = new RelativeLayout.LayoutParams(
- (int) (100 * metrics.density),
- RelativeLayout.LayoutParams.WRAP_CONTENT);
-
在父容器中设置
- lp.addRule(RelativeLayout.ALIGN_PARENT_RIGHT);
- lp.addRule(RelativeLayout.ALIGN_PARENT_TOP);
设置顶层
bringChildToFront((Button)findViewById(R.id.button1));