what I want to implement is a screen where I have RecyclerView that shows a list .. it may has many or few items, when it has many items the Button must be floating and sticky at the end of the screen.
and if the items are few, where there is an empty space in the screen, the button must appear as the final element in the RecyclerView list.
the button is a rectangular raised button with a background. is there any suggestion how to achieve something like this.
doing like that
<FrameLayout android:layout_width="match_parent" android:layout_height="wrap_content"> <android.support.v7.widget.RecyclerView android:id="@+id/recycler_view" android:scrollbars="vertical" android:layout_width="match_parent" android:layout_height="wrap_content"/> <Button android:layout_gravity="bottom|center_horizontal" android:layout_width="wrap_content" android:layout_height="wrap_content" /> </FrameLayout> That's the result when has many item
and when has few item
You can do something like this,
<LinearLayout android:layout_width="match_parent" android:layout_height="wrap_content" android:weight_sum ="10"> <android.support.v7.widget.RecyclerView android:id="@+id/recycler_view" android:scrollbars="vertical" android:layout_width="match_parent" android:layout_height="0dp" android:layout_weight="9"/> <Button android:text="button" android:layout_width="match_parent" android:layout_height="0dp" android:layout_weight="1"/> </LinearLayout> this is same as answer above. But difference is that the button will be always aligned at the bottom with weight 1.
One option is to have the button floating the whole time above the list view, and position it manually to make it appear to be at the bottom of the list. if you control the position you can determine when it should stick at the bottom.
see this post on how to get the height of an view at runtime.
view.measure(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT); int height=view.getMeasuredHeight(); and see this article for how to get the screen height
int screenHeight = getWindowManager().getDefaultDisplay().getHeight() then in your layout.xml you can put
`android:layout_alignParentBottom="true"` on the element then use this information to position the button
and now the magic happens
int offset = screenHeight - ButtonHeight - listHeight; if(offset < 0) offset = 0; btn.setTop(offset); 