恢复webview实现NestedScrollingChild接口

2020-05-13 12:29:00 +08:00
parent 7342d0706f
commit c1caa23b10
7 changed files with 168 additions and 85 deletions
--- a/app/src/main/java/com/gh/common/view/NestedScrollWebView.java
+++ b/app/src/main/java/com/gh/common/view/NestedScrollWebView.java
@ -0,0 +1,164 @@
+package com.gh.common.view;
+import android.content.Context;
+import android.util.AttributeSet;
+import android.view.MotionEvent;
+
+import androidx.core.view.MotionEventCompat;
+import androidx.core.view.NestedScrollingChild;
+import androidx.core.view.NestedScrollingChildHelper;
+import androidx.core.view.ViewCompat;
+import wendu.dsbridge.DWebView;
+
+public class NestedScrollWebView extends DWebView implements NestedScrollingChild {
+
+    public static final String TAG = NestedScrollWebView.class.getSimpleName();
+
+    private int mLastMotionY;
+
+    private final int[] mScrollOffset = new int[2];
+    private final int[] mScrollConsumed = new int[2];
+
+    private int mNestedYOffset;
+    private boolean mChange;
+
+    private NestedScrollingChildHelper mChildHelper;
+
+    public NestedScrollWebView(Context context) {
+        super(context);
+        init();
+    }
+
+    public NestedScrollWebView(Context context, AttributeSet attrs) {
+        super(context, attrs);
+        init();
+    }
+
+
+    private void init() {
+        mChildHelper = new NestedScrollingChildHelper(this);
+        setNestedScrollingEnabled(true);
+    }
+
+    @Override
+    public boolean dispatchTouchEvent(MotionEvent ev) {
+        getParent().requestDisallowInterceptTouchEvent(true);
+        return super.dispatchTouchEvent(ev);
+    }
+
+    @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);
+                mChange = false;
+                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];
+                }
+
+                int oldY = getScrollY();
+                mLastMotionY = y - mScrollOffset[1];
+                int newScrollY = Math.max(0, oldY + deltaY);
+                deltaY -= newScrollY - oldY;
+                if (dispatchNestedScroll(0, newScrollY - deltaY, 0, deltaY, mScrollOffset)) {
+                    mLastMotionY -= mScrollOffset[1];
+                    trackedEvent.offsetLocation(0, mScrollOffset[1]);
+                    mNestedYOffset += mScrollOffset[1];
+                }
+                if(mScrollConsumed[1]==0 && mScrollOffset[1]==0) {
+                    if(mChange){
+                        mChange =false;
+                        trackedEvent.setAction(MotionEvent.ACTION_DOWN);
+                        super.onTouchEvent(trackedEvent);
+                    }else {
+                        result = super.onTouchEvent(trackedEvent);
+                    }
+                    trackedEvent.recycle();
+                }else{
+                    if(Math.abs(mLastMotionY - y) >= 10) {
+                        if (!mChange) {
+                            mChange = true;
+                            super.onTouchEvent(MotionEvent.obtain(0, 0, MotionEvent.ACTION_CANCEL, 0, 0, 0));
+                        }
+                    }
+
+                }
+                break;
+            case MotionEvent.ACTION_POINTER_DOWN:
+            case MotionEvent.ACTION_UP:
+            case MotionEvent.ACTION_CANCEL:
+                stopNestedScroll();
+                result = super.onTouchEvent(event);
+                break;
+        }
+        return result;
+    }
+
+    // NestedScrollingChild
+    @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);
+    }
+
+}