100 lines
3.5 KiB
Java
100 lines
3.5 KiB
Java
package androidx.viewpager2.widget;
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import android.os.SystemClock;
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import android.view.MotionEvent;
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import android.view.VelocityTracker;
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import android.view.ViewConfiguration;
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import androidx.annotation.UiThread;
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import androidx.recyclerview.widget.RecyclerView;
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public final class FakeDrag {
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private int mActualDraggedDistance;
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private long mFakeDragBeginTime;
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private int mMaximumVelocity;
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private final RecyclerView mRecyclerView;
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private float mRequestedDragDistance;
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private final ScrollEventAdapter mScrollEventAdapter;
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private VelocityTracker mVelocityTracker;
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private final ViewPager2 mViewPager;
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public FakeDrag(ViewPager2 viewPager2, ScrollEventAdapter scrollEventAdapter, RecyclerView recyclerView) {
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this.mViewPager = viewPager2;
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this.mScrollEventAdapter = scrollEventAdapter;
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this.mRecyclerView = recyclerView;
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}
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private void addFakeMotionEvent(long j, int i, float f, float f2) {
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MotionEvent obtain = MotionEvent.obtain(this.mFakeDragBeginTime, j, i, f, f2, 0);
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this.mVelocityTracker.addMovement(obtain);
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obtain.recycle();
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}
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private void beginFakeVelocityTracker() {
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VelocityTracker velocityTracker = this.mVelocityTracker;
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if (velocityTracker == null) {
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this.mVelocityTracker = VelocityTracker.obtain();
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this.mMaximumVelocity = ViewConfiguration.get(this.mViewPager.getContext()).getScaledMaximumFlingVelocity();
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return;
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}
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velocityTracker.clear();
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}
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@UiThread
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public boolean beginFakeDrag() {
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if (this.mScrollEventAdapter.isDragging()) {
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return false;
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}
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this.mActualDraggedDistance = 0;
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this.mRequestedDragDistance = (float) 0;
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this.mFakeDragBeginTime = SystemClock.uptimeMillis();
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beginFakeVelocityTracker();
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this.mScrollEventAdapter.notifyBeginFakeDrag();
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if (!this.mScrollEventAdapter.isIdle()) {
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this.mRecyclerView.stopScroll();
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}
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addFakeMotionEvent(this.mFakeDragBeginTime, 0, 0.0f, 0.0f);
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return true;
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}
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@UiThread
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public boolean endFakeDrag() {
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if (!this.mScrollEventAdapter.isFakeDragging()) {
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return false;
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}
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this.mScrollEventAdapter.notifyEndFakeDrag();
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VelocityTracker velocityTracker = this.mVelocityTracker;
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velocityTracker.computeCurrentVelocity(1000, (float) this.mMaximumVelocity);
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if (this.mRecyclerView.fling((int) velocityTracker.getXVelocity(), (int) velocityTracker.getYVelocity())) {
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return true;
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}
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this.mViewPager.snapToPage();
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return true;
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}
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@UiThread
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public boolean fakeDragBy(float f) {
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int i = 0;
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if (!this.mScrollEventAdapter.isFakeDragging()) {
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return false;
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}
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float f2 = this.mRequestedDragDistance - f;
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this.mRequestedDragDistance = f2;
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int round = Math.round(f2 - ((float) this.mActualDraggedDistance));
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this.mActualDraggedDistance += round;
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long uptimeMillis = SystemClock.uptimeMillis();
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boolean z2 = this.mViewPager.getOrientation() == 0;
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int i2 = z2 ? round : 0;
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if (!z2) {
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i = round;
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}
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float f3 = z2 ? this.mRequestedDragDistance : 0.0f;
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float f4 = z2 ? 0.0f : this.mRequestedDragDistance;
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this.mRecyclerView.scrollBy(i2, i);
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addFakeMotionEvent(uptimeMillis, 2, f3, f4);
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return true;
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}
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public boolean isFakeDragging() {
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return this.mScrollEventAdapter.isFakeDragging();
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}
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}
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