第一种
public class MyViewPager extends ViewPager { public MyViewPager(@NonNull Context context) { super(context); } public MyViewPager(@NonNull Context context, @Nullable AttributeSet attrs) { super(context, attrs); } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { int height = 0; for (int i = 0; i < getChildCount(); i++) { View child = getChildAt(i); child.measure(widthMeasureSpec, MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED)); int h = child.getMeasuredHeight(); if (h > height) height = h; } heightMeasureSpec = MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY); super.onMeasure(widthMeasureSpec, heightMeasureSpec); } }
弊端:每个viewpager高度一样,导致有的画面会有大空白
第二种
public class CustomViewpager extends ViewPager { public CustomViewpager(Context context) { super(context); } public CustomViewpager(Context context, AttributeSet attrs) { super(context, attrs); } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { int viewHeight = 0; View childView = getChildAt(getCurrentItem()); if (childView != null) { childView.measure(widthMeasureSpec, MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED)); viewHeight = childView.getMeasuredHeight(); heightMeasureSpec = MeasureSpec.makeMeasureSpec(viewHeight, MeasureSpec.EXACTLY); } super.onMeasure(widthMeasureSpec, heightMeasureSpec); } }
在viewpager中
viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() { @Override public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) { } @Override public void onPageSelected(int position) { selectionViewPager(position); View view = viewPager.getChildAt(position); int height = view.getMeasuredHeight(); LinearLayout.LayoutParams layoutParams = (LinearLayout.LayoutParams) viewPager.getLayoutParams(); layoutParams.height = height; viewPager.setLayoutParams(layoutParams); } @Override public void onPageScrollStateChanged(int state) { } });