package com.aries.ui.view.nested; import android.content.Context; import android.util.AttributeSet; import android.view.MotionEvent; import android.widget.FrameLayout; import androidx.annotation.NonNull; import androidx.annotation.Nullable; import androidx.core.view.MotionEventCompat; import androidx.core.view.NestedScrollingChild; import androidx.core.view.NestedScrollingChildHelper; import androidx.core.view.ViewCompat; /** * @Author: AriesHoo on 2019/8/6 16:30 * @E-Mail: [email protected] * @Function: 结合CoordinatorLayout可以与Toolbar联动的FrameLayout * @Description: */ public class NestedFrameLayout extends FrameLayout implements NestedScrollingChild { private int mLastMotionY; private final int[] mScrollOffset = new int[2]; private final int[] mScrollConsumed = new int[2]; private int mNestedYOffset; private NestedScrollingChildHelper mChildHelper; public NestedFrameLayout(@NonNull Context context) { this(context, null); } public NestedFrameLayout(@NonNull Context context, @Nullable AttributeSet attrs) { this(context, attrs, 0); } public NestedFrameLayout(@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); init(); } private void init() { mChildHelper = new NestedScrollingChildHelper(this); setNestedScrollingEnabled(true); } @Override public boolean onTouchEvent(MotionEvent event) { boolean result = false; MotionEvent trackedEvent = MotionEvent.obtain(event); final int action = MotionEventCompat.getActionMasked(event); if (action == MotionEvent.ACTION_DOWN) { mNestedYOffset = 0; } int y = (int) event.getY(); event.offsetLocation(0, mNestedYOffset); switch (action) { case MotionEvent.ACTION_DOWN: mLastMotionY = y; startNestedScroll(ViewCompat.SCROLL_AXIS_VERTICAL); result = super.onTouchEvent(event); break; case MotionEvent.ACTION_MOVE: int deltaY = mLastMotionY - y; if (dispatchNestedPreScroll(0, deltaY, mScrollConsumed, mScrollOffset)) { deltaY -= mScrollConsumed[1]; trackedEvent.offsetLocation(0, mScrollOffset[1]); mNestedYOffset += mScrollOffset[1]; } mLastMotionY = y - mScrollOffset[1]; int oldY = getScrollY(); int newScrollY = Math.max(0, oldY + deltaY); int dyConsumed = newScrollY - oldY; int dyUnconsumed = deltaY - dyConsumed; if (dispatchNestedScroll(0, dyConsumed, 0, dyUnconsumed, mScrollOffset)) { mLastMotionY -= mScrollOffset[1]; trackedEvent.offsetLocation(0, mScrollOffset[1]); mNestedYOffset += mScrollOffset[1]; } result = super.onTouchEvent(trackedEvent); trackedEvent.recycle(); break; case MotionEvent.ACTION_POINTER_DOWN: case MotionEvent.ACTION_UP: case MotionEvent.ACTION_CANCEL: stopNestedScroll(); result = super.onTouchEvent(event); break; default: break; } return result; } @Override public void setNestedScrollingEnabled(boolean enabled) { mChildHelper.setNestedScrollingEnabled(enabled); } @Override public boolean isNestedScrollingEnabled() { return mChildHelper.isNestedScrollingEnabled(); } @Override public boolean startNestedScroll(int axes) { return mChildHelper.startNestedScroll(axes); } @Override public void stopNestedScroll() { mChildHelper.stopNestedScroll(); } @Override public boolean hasNestedScrollingParent() { return mChildHelper.hasNestedScrollingParent(); } @Override public boolean dispatchNestedScroll(int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed, int[] offsetInWindow) { return mChildHelper.dispatchNestedScroll(dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed, offsetInWindow); } @Override public boolean dispatchNestedPreScroll(int dx, int dy, int[] consumed, int[] offsetInWindow) { return mChildHelper.dispatchNestedPreScroll(dx, dy, consumed, offsetInWindow); } @Override public boolean dispatchNestedFling(float velocityX, float velocityY, boolean consumed) { return mChildHelper.dispatchNestedFling(velocityX, velocityY, consumed); } @Override public boolean dispatchNestedPreFling(float velocityX, float velocityY) { return mChildHelper.dispatchNestedPreFling(velocityX, velocityY); } }