如何获得用户滚动百分比? [英] how to get percentage scrolled by the user?

问题描述

我有一个带有文本的滚动视图，并在底部有一个按钮.我想要做的是根据用户完成的滚动百分比更改按钮上的文本.这是我的代码:

i have a scrollview with text in it and a button at the bottom. what i want to do is change the text on the button according to the percentage of scrolling done by the user. this is my code:

public class Verbal extends Activity implements ScrollViewListener {

@Override
protected void onCreate(Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    super.onCreate(savedInstanceState);
    setContentView(R.layout.verbal);
    ObservableScrollView scrollview = (ObservableScrollView) findViewById(R.id.scrollview);
    scrollview.setScrollViewListener(this);

}

@Override
public void onScrollChanged(ObservableScrollView scrollView, int x, int y,
        int oldx, int oldy) {
    // TODO Auto-generated method stub
    Button answer = (Button) findViewById(R.id.answernumber);

    int totalHeight = scrollView.getChildAt(0).getHeight();
    int p = (y/totalHeight)*100;

    if (p>3 && p<8)
        answer.setText("1");
    else if (p>8 && p<11)
        answer.setText("2");
    else if (p>11 && p<14)
        answer.setText("3");
    else if (p>14 && p<17)
        answer.setText("4");
    else if (p>17 && p<21) 
        answer.setText("5");
    else if (p>21 && p<25)
        answer.setText("6");
    else if (p>25 && p<29)
        answer.setText("7");
    else if (p>29 && p<31)
        answer.setText("8");
    else if (p>31 && p<35)
        answer.setText("9");
    else if (p>35 && p<39)
        answer.setText("10");
    else if (p>39 && p<45)
        answer.setText("11");
    else if (p>45 && p<50)
        answer.setText("12");
    else if (p>50 && p<56)
        answer.setText("13");
    else if (p>56 && p<62)
        answer.setText("14");
    else if (p>62 && p<67)
        answer.setText("15");
    else if (p>67 && p<72)
        answer.setText("16");
    else if (p>72 && p<78)
        answer.setText("17");
    else if (p>78 && p<83)
        answer.setText("18");
    else if (p>83 && p<86)
        answer.setText("19");
    else if (p>86)
        answer.setText("20");   




}

}

问题在于按钮中的文本没有更改，因为最初的"y"值为零，因此"p"也为零.但是当用户向下滚动时，"y"值和"p"剂量值会发生变化.我需要随着"y"的变化不断改变"p"的值.请以编程方式帮助我该怎么办?

the problem is the text is not changing in the button because initially the value of 'y' is zero so 'p' is also zero. but as the user scrolls down value of 'y' changes and 'p' dosent change. i need to continuously change value of 'p' as 'y' changes. please help me programmatically what to do?

推荐答案

我认为您的问题是您正在运行整数除法，因此p始终为0.您必须像这样将其转换为两倍:

I think your problem is that you're running a integer division, and thus p is always 0. You have to cast it to double like this:

 double p = ((double)y/(double)totalHeight)*100;

这篇关于如何获得用户滚动百分比?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！