在Scrollview中使用FragmentStatePagerAdapter,Viewpager时出现问题

Question

我在用:

• activity 包含以fragment编程方式添加的布局.
• 父片段具有FragmentStatePagerAdapter视图寻呼机,所有内容都在里面ScrollView.
• 查看寻呼机充满了一些具有Recyclerview的子片段.

问题是:

• View pager片段有一个列表,所以我必须以编程方式设置父视图寻呼机高度.但我不能这样做.

为此,我用过

viewpager.getLayoutParams().height = 20000;
viewpager.requestLayout();`

和

ViewGroup.LayoutParams params = viewPagerBottom.getLayoutParams();
params.height =  20000;
viewPagerBottom.setLayoutParams(params);

另外,我尝试过查看寻呼机和查看寻呼机片段高度属性 wrap_content

• 如果我没有设置scrollview android:layout_height="match_parent",则看不到视图寻呼机内容android:fillViewport="true".

它是父片段layout.xml.

<ScrollView
    style="@style/scrollDefaultStyle"
    android:layout_height="wrap_content"
    android:fillViewport="true"
    >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <TabLayout .... />

        <android.support.v4.view.ViewPager
            android:layout_width="match_parent"
            android:layout_height="0dp"
            android:layout_weight="1" />

    </LinearLayout>
</ScrollView>

Answer 1

您可以自定义ViewPager以ViewPager从此答案页面滑动调整其当前页面大小.

您可以使用以下代码:

 public class WrapContentViewPager extends ViewPager {

        private int mCurrentPagePosition = 0;

        public WrapContentViewPager(Context context) {
            super(context);
        }

        public WrapContentViewPager(Context context, AttributeSet attrs) {
            super(context, attrs);
        }

        @Override
        protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        try {
             boolean wrapHeight = MeasureSpec.getMode(heightMeasureSpec) == MeasureSpec.AT_MOST;
             if (wrapHeight) {
                 View child = getChildAt(mCurrentPagePosition);
                 if (child != null) {
                 child.measure(widthMeasureSpec, MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
                 int h = child.getMeasuredHeight();

                 heightMeasureSpec = MeasureSpec.makeMeasureSpec(h, MeasureSpec.EXACTLY);
                }
            }
    } catch (Exception e) {
        e.printStackTrace();
    }
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }

        public void reMeasureCurrentPage(int position) {
            mCurrentPagePosition = position;
            requestLayout();
        }
    }

在xml中声明它:

    <your.package.name.WrapContentViewPager
            android:id="@+id/view_pager"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
    </your.package.name.WrapContentViewPager>

在reMeasureCurrentpage页面滑动后调用该功能.

    final WrapContentViewPager wrapContentViewPager = (WrapContentViewPager) findViewById(R.id.view_pager);

    wrapContentViewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
                @Override
                public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

                }

                @Override
                public void onPageSelected(int position) {
                    wrapContentViewPager.reMeasureCurrentPage(wrapContentViewPager.getCurrentItem());
                }

                @Override
                public void onPageScrollStateChanged(int state) {

                }
            });

注意:可能有数百行ListView.这不是用好主意wrap_content了ListView.你要么需要给予固定高度,ListView要么你需要使用match_parent.