47 lines
1.4 KiB
Java
47 lines
1.4 KiB
Java
package androidx.core.widget;
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import android.widget.ListView;
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import androidx.annotation.NonNull;
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public class ListViewAutoScrollHelper extends AutoScrollHelper {
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private final ListView mTarget;
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public ListViewAutoScrollHelper(@NonNull ListView listView) {
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super(listView);
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this.mTarget = listView;
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}
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@Override // androidx.core.widget.AutoScrollHelper
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public boolean canTargetScrollHorizontally(int i) {
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return false;
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}
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@Override // androidx.core.widget.AutoScrollHelper
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public boolean canTargetScrollVertically(int i) {
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ListView listView = this.mTarget;
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int count = listView.getCount();
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if (count == 0) {
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return false;
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}
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int childCount = listView.getChildCount();
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int firstVisiblePosition = listView.getFirstVisiblePosition();
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int i2 = firstVisiblePosition + childCount;
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if (i > 0) {
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if (i2 >= count && listView.getChildAt(childCount - 1).getBottom() <= listView.getHeight()) {
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return false;
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}
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} else if (i >= 0) {
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return false;
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} else {
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if (firstVisiblePosition <= 0 && listView.getChildAt(0).getTop() >= 0) {
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return false;
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}
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}
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return true;
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}
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@Override // androidx.core.widget.AutoScrollHelper
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public void scrollTargetBy(int i, int i2) {
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ListViewCompat.scrollListBy(this.mTarget, i2);
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}
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}
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