private Toast mToast = null;
public void showTextToast(String msg) {
if (mToast == null) {
mToast = Toast.makeText(mContext, msg, Toast.LENGTH_SHORT);
} else {
mToast.setText(msg);
}
mToast.show();
}
原文：http://www.cnblogs.com/wxmdevelop/p/5543693.html