简体   繁体   中英

Set Margin on RecyclerView programmatically

I need to set the top margin on a RecyclerView programmatically, but I get this exception:

java.lang.RuntimeException: Unable to resume activity java.lang.ClassCastException: android.view.ViewGroup$LayoutParams cannot be cast to android.support.v7.widget.RecyclerView$LayoutParams

Here is my code:

RecyclerView.LayoutParams layoutParams = (RecyclerView.LayoutParams)recyclerView.getLayoutParams();
int marginTopDp = (int)getResources().getDimension(R.dimen.margin);
int marginTopPx = (int) (marginTopDp * getResources().getDisplayMetrics().density + 0.5f);
layoutParams.setMargins(0, marginTopPx, 0, 0);
recyclerView.setLayoutParams(layoutParams);

If I use the ViewGroup.LayoutParams layoutParams = recyclerView.getLayoutParams as the stack trace suggests, I cannot call setMargin anymore as that method does not exist for ViewGroup.LayoutParams .

Any help would be appreciated.

Try this out. You can refer to this for more info.

ViewGroup.MarginLayoutParams marginLayoutParams = new ViewGroup.MarginLayoutParams(mRecyclerView.getLayoutParams());
marginLayoutParams.setMargins(0, 10, 0, 10);
mRecyclerView.setLayoutParams(marginLayoutParams);

for me, the parent of recyclerview is a constraintLayout ,

        val margins = (rv.layoutParams as ConstraintLayout.LayoutParams).apply {
        leftMargin = 0
        rightMargin = 0
    }
    rv.layoutParams = margins

or it will get cast error, viewGroup.LayoutParams can't be cast to COnstarintLayout.LayoutParams

You need use new object of MargingLayoutParams

    final FrameLayout.MarginLayoutParams marginLayoutParams = new      
                      FrameLayout.MarginLayoutParams(rvContacts.getLayoutParams());
    marginLayoutParams.leftMargin = left;
    marginLayoutParams.topMargin = top;
    marginLayoutParams.rightMargin = right;
    marginLayoutParams.bottomMargin = bottom;

    recyclerView.setLayoutParams(marginLayoutParams);
    recyclerView.requestLayout();

I am also facing this type of issue, Use below code to handle margin issue of recyclerview.

    ViewGroup.MarginLayoutParams marginLayoutParams=
    (ViewGroup.MarginLayoutParams) recyclerView.getLayoutParams();

    // here i try to set only top margin, Get dimension from dimension file.
    int topMargin =  getResources()
    .getDimensionPixelSize(R.dimen.top_margin);

    marginLayoutParams.setMargins(marginLayoutParams.getMarginStart(),
    topMargin, marginLayoutParams.getMarginEnd(), marginLayoutParams.bottomMargin);

    recyclerView.setLayoutParams(marginLayoutParams);

Padding usage with clipToPadding="false" did the trick in my case. [Kotlin]

So I added android:clipToPadding="false" to my RecyclerView in xml. Can be done programmatically as well.

And then just used:

recyclerView.setPadding(10, 0, 0, someSpace)

someSpace is dp variable in case you need it.

resources.getDimension(R.dimen.some_space).toInt() PS don't forget to create some_space in dimension file :)

The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.

 
粤ICP备18138465号  © 2020-2024 STACKOOM.COM