我试图找到一种方法来设置列表视图的基础上，其子项的高度的高度。我跟着这里给出的解决方案： How我可以把一个ListView成滚动型没有它崩溃？

I'm trying to find a way to set the height of a listview based on the height of its children items. I followed the solution given here: How can I put a ListView into a ScrollView without it collapsing?

public void setListViewHeightBasedOnChildren(ListView listView) {
    ListAdapter listAdapter = listView.getAdapter();
    if (listAdapter == null) {
        // pre-condition
        return;
    }

    int totalHeight = 0;

    for (int i = 0; i < listAdapter.getCount(); i++) {
        View listItem = listAdapter.getView(i, null, listView);

        if(listItem != null){
            listItem.setLayoutParams(new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT));                
            listItem.measure(MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
            //listItem.measure(0, 0);
            totalHeight += listItem.getMeasuredHeight();
        }
    }

    ViewGroup.LayoutParams params = listView.getLayoutParams();
    params.height = totalHeight + (listView.getDividerHeight() * (listAdapter.getCount() - 1));
    listView.setLayoutParams(params);
    listView.requestLayout();
}

现在我调用上面的函数像这样的列表视图：

Now I call the above function on the listview like this:

public void displayReviews(ArrayList<Reviews> resultReviews){
    // Hide the loading progress
    hideReviewsLoading();

    if(resultReviews != null && resultReviews.size() > 0){
        mCurrentReviewList.onFetchFinished(resultReviews);
        setListViewHeightBasedOnChildren(mCurrentReviewList.getListView());
    }
    else{
        // Display a generic text to indicate no reviews are in yet
        displayEmptyText();
    }
}

下面上方mCurrentreviewList是一个ListFragment它基本上具有一个适配器以设置一个布局中的元素

Here above the mCurrentreviewList is a ListFragment which basically has an adapter to set the elements within a layout.

时遇到的问题是，每个的高度的listItem它测量是不准确的。所以在最后，当所有的列表项（评论）填充整个列表视图包含它，从来没有完全显示所有列表项。它切断下面的地方 - 像只显示7.5审查了10总。

The problem I'm having is that the height of each listitem that it measures is not accurate. And so in the end when all the list items(reviews) are populated the overall listview that contains it, never fully displays all the list items. It cuts off somewhere below - Like only shows 7.5 reviews out of a 10 total.

我不知道我在做什么错误。任何帮助和指导将大大AP preciated！

I'm not sure what I'm doing incorrectly. Any help and direction would be greatly appreciated!

推荐答案

好了的样子，我能够弄清楚为什么测量是不准确的。我试图通过传递让ListView的高度的测量

Ok looks like I was able to figure out why the measurement was inaccurate. I was trying to get a measurement of the listview's height by passing

listItem.measure(MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED), MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));

有关列表项的具有可变/动态的高度，这是不行的。测量必须知道至少一个变量与在这种情况下，这将是恒定的宽度。因此，首先计算你知道将是恒定的，通过使用列表视图中所需的宽度：

For ListItem's with variable/dynamic height, this will not work out. The measurement has to know at least one variable and in this case it will be the constant width. So, first calculate the desired width of the listview which you know is going to be constant, by using:

int desiredWidth = MeasureSpec.makeMeasureSpec(listView.getWidth(), MeasureSpec.AT_MOST);

然后把它传递给列表项措施。全部code为如下：

and then pass it to the listitem measure. Full code is given below:

public void setListViewHeightBasedOnChildren(ListView listView) {
    ListAdapter listAdapter = listView.getAdapter();
    if (listAdapter == null) {
        // pre-condition
        return;
    }

    int totalHeight = listView.getPaddingTop() + listView.getPaddingBottom();
    int desiredWidth = MeasureSpec.makeMeasureSpec(listView.getWidth(), MeasureSpec.AT_MOST);
    for (int i = 0; i < listAdapter.getCount(); i++) {
        View listItem = listAdapter.getView(i, null, listView);

        if(listItem != null){
            // This next line is needed before you call measure or else you won't get measured height at all. The listitem needs to be drawn first to know the height.
            listItem.setLayoutParams(new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT));
            listItem.measure(desiredWidth, MeasureSpec.UNSPECIFIED);
            totalHeight += listItem.getMeasuredHeight();

        }
    }

    ViewGroup.LayoutParams params = listView.getLayoutParams();
    params.height = totalHeight + (listView.getDividerHeight() * (listAdapter.getCount() - 1));
    listView.setLayoutParams(params);
    listView.requestLayout();
}

请注意：的这是一个hackish的实现，是不推荐的方式。请参阅How我可以把一个ListView成滚动型没有它崩溃？并了解你在做什么实现此之前。

Please Note This is a hackish implementation and isn't the recommended way. Please see How can I put a ListView into a ScrollView without it collapsing? and understand exactly what you are doing before implementing this.