项目中遇到当TextView显示的数据不超过3行的时候，不显示下面的展开按钮，这时候就必须要获取到此时TextView的行数，查看api发现了getLineCount()方法，当我兴高采烈地使用时，却放心返回值总为空，后来查谷歌才发现说是要先把TextView完全画出来，才能获取行数，并说解决方法就是开启异步去获取，下面是具体的方法：
private class MyOpenTask extends AsyncTask<Integer, Integer, Integer> {
private int[] location = new int[2];
@Override
protected void onCancelled() {
super.onCancelled();
}
public void start() {
execute(0);
}
@Override
protected Integer doInBackground(Integer... params) {
return 1;
}
@Override
protected void onPostExecute(Integer result) {
super.onPostExecute(result);
int linecount = mVideoDescription.getLineCount();
android.util.Log.e("MvDetail", "linecount1::"+linecount);
if(linecount>3){
openTV.setVisibility(View.VISIBLE);
openIV.setVisibility(View.VISIBLE);
openTV.setText("展开全部");
mVideoDescription.setClickable(true);
openFlag = false;
}else{
openTV.setVisibility(View.GONE);
openIV.setVisibility(View.GONE);
mVideoDescription.setClickable(false);
}
}
}
