41 lines
1.4 KiB
Java
41 lines
1.4 KiB
Java
package androidx.viewpager2.widget;
|
|
|
|
import android.view.View;
|
|
import android.view.ViewParent;
|
|
import androidx.annotation.NonNull;
|
|
import androidx.annotation.Px;
|
|
import androidx.core.util.Preconditions;
|
|
import androidx.recyclerview.widget.RecyclerView;
|
|
import androidx.viewpager2.widget.ViewPager2;
|
|
public final class MarginPageTransformer implements ViewPager2.PageTransformer {
|
|
private final int mMarginPx;
|
|
|
|
public MarginPageTransformer(@Px int i) {
|
|
Preconditions.checkArgumentNonnegative(i, "Margin must be non-negative");
|
|
this.mMarginPx = i;
|
|
}
|
|
|
|
private ViewPager2 requireViewPager(@NonNull View view) {
|
|
ViewParent parent = view.getParent();
|
|
ViewParent parent2 = parent.getParent();
|
|
if ((parent instanceof RecyclerView) && (parent2 instanceof ViewPager2)) {
|
|
return (ViewPager2) parent2;
|
|
}
|
|
throw new IllegalStateException("Expected the page view to be managed by a ViewPager2 instance.");
|
|
}
|
|
|
|
@Override // androidx.viewpager2.widget.ViewPager2.PageTransformer
|
|
public void transformPage(@NonNull View view, float f) {
|
|
ViewPager2 requireViewPager = requireViewPager(view);
|
|
float f2 = ((float) this.mMarginPx) * f;
|
|
if (requireViewPager.getOrientation() == 0) {
|
|
if (requireViewPager.isRtl()) {
|
|
f2 = -f2;
|
|
}
|
|
view.setTranslationX(f2);
|
|
return;
|
|
}
|
|
view.setTranslationY(f2);
|
|
}
|
|
}
|