diff options
| -rw-r--r-- | core/java/android/view/View.java | 24 | ||||
| -rw-r--r-- | core/java/android/view/ViewRootImpl.java | 96 |
2 files changed, 99 insertions, 21 deletions
diff --git a/core/java/android/view/View.java b/core/java/android/view/View.java index 080e7c0..97287c3 100644 --- a/core/java/android/view/View.java +++ b/core/java/android/view/View.java @@ -15509,17 +15509,27 @@ public class View implements Drawable.Callback, KeyEvent.Callback, * handle possible request-during-layout errors correctly.</p> */ public void requestLayout() { - ViewRootImpl viewRoot = getViewRootImpl(); - if (viewRoot != null && viewRoot.isInLayout()) { - viewRoot.requestLayoutDuringLayout(this); - return; + if (mAttachInfo != null && mAttachInfo.mViewRequestingLayout == null) { + // Only trigger request-during-layout logic if this is the view requesting it, + // not the views in its parent hierarchy + ViewRootImpl viewRoot = getViewRootImpl(); + if (viewRoot != null && viewRoot.isInLayout()) { + if (!viewRoot.requestLayoutDuringLayout(this)) { + return; + } + } + mAttachInfo.mViewRequestingLayout = this; } + mPrivateFlags |= PFLAG_FORCE_LAYOUT; mPrivateFlags |= PFLAG_INVALIDATED; if (mParent != null && !mParent.isLayoutRequested()) { mParent.requestLayout(); } + if (mAttachInfo != null && mAttachInfo.mViewRequestingLayout == this) { + mAttachInfo.mViewRequestingLayout = null; + } } /** @@ -18000,6 +18010,12 @@ public class View implements Drawable.Callback, KeyEvent.Callback, final Point mPoint = new Point(); /** + * Used to track which View originated a requestLayout() call, used when + * requestLayout() is called during layout. + */ + View mViewRequestingLayout; + + /** * Creates a new set of attachment information with the specified * events handler and thread. * diff --git a/core/java/android/view/ViewRootImpl.java b/core/java/android/view/ViewRootImpl.java index 85fab28..9377cd4 100644 --- a/core/java/android/view/ViewRootImpl.java +++ b/core/java/android/view/ViewRootImpl.java @@ -1894,22 +1894,37 @@ public final class ViewRootImpl implements ViewParent, } /** - * Called by {@link android.view.View#requestLayout()} if the view hiearchy is currently - * undergoing a layout pass. requestLayout() should not be called during layout, but if it - * is called anyway, we handle the situation here rather than leave the hierarchy in an - * indeterminate state. The solution is to queue up all requests during layout, apply those - * requests as soon as layout is complete, and then run layout once more immediately. If + * Called by {@link android.view.View#requestLayout()} if the view hierarchy is currently + * undergoing a layout pass. requestLayout() should not generally be called during layout, + * unless the container hierarchy knows what it is doing (i.e., it is fine as long as + * all children in that container hierarchy are measured and laid out at the end of the layout + * pass for that container). If requestLayout() is called anyway, we handle it correctly + * by registering all requesters during a frame as it proceeds. At the end of the frame, + * we check all of those views to see if any still have pending layout requests, which + * indicates that they were not correctly handled by their container hierarchy. If that is + * the case, we clear all such flags in the tree, to remove the buggy flag state that leads + * to blank containers, and force a second request/measure/layout pass in this frame. If * more requestLayout() calls are received during that second layout pass, we post those - * requests to the next frame, to avoid possible infinite loops. + * requests to the next frame to avoid possible infinite loops. + * + * <p>The return value from this method indicates whether the request should proceed + * (if it is a request during the first layout pass) or should be skipped and posted to the + * next frame (if it is a request during the second layout pass).</p> * * @param view the view that requested the layout. + * + * @return true if request should proceed, false otherwise. */ - void requestLayoutDuringLayout(final View view) { + boolean requestLayoutDuringLayout(final View view) { + if (view.mParent == null || view.mAttachInfo == null) { + // Would not normally trigger another layout, so just let it pass through as usual + return true; + } if (!mHandlingLayoutInLayoutRequest) { if (!mLayoutRequesters.contains(view)) { - Log.w("View", "requestLayout() called by " + view + " during layout pass"); mLayoutRequesters.add(view); } + return true; } else { Log.w("View", "requestLayout() called by " + view + " during second layout pass: " + "posting to next frame"); @@ -1919,6 +1934,7 @@ public final class ViewRootImpl implements ViewParent, view.requestLayout(); } }); + return false; } } @@ -1937,20 +1953,66 @@ public final class ViewRootImpl implements ViewParent, Trace.traceBegin(Trace.TRACE_TAG_VIEW, "layout"); try { host.layout(0, 0, host.getMeasuredWidth(), host.getMeasuredHeight()); + mInLayout = false; int numViewsRequestingLayout = mLayoutRequesters.size(); if (numViewsRequestingLayout > 0) { - // requestLayout() was called during layout: unusual, but try to handle correctly - mHandlingLayoutInLayoutRequest = true; + // requestLayout() was called during layout. + // If no layout-request flags are set on the requesting views, there is no problem. + // If some requests are still pending, then we need to clear those flags and do + // a full request/measure/layout pass to handle this situation. + + // Check state of layout flags for all requesters + ArrayList<View> mValidLayoutRequesters = null; for (int i = 0; i < numViewsRequestingLayout; ++i) { - mLayoutRequesters.get(i).requestLayout(); + View view = mLayoutRequesters.get(i); + if ((view.mPrivateFlags & View.PFLAG_FORCE_LAYOUT) == View.PFLAG_FORCE_LAYOUT) { + while (view != null && view.mAttachInfo != null && view.mParent != null && + (view.mPrivateFlags & View.PFLAG_FORCE_LAYOUT) != 0) { + if ((view.mViewFlags & View.VISIBILITY_MASK) != View.GONE) { + // Only trigger new requests for non-GONE views + Log.w(TAG, "requestLayout() improperly called during " + + "layout: running second layout pass for " + view); + if (mValidLayoutRequesters == null) { + mValidLayoutRequesters = new ArrayList<View>(); + } + mValidLayoutRequesters.add(view); + break; + } + if (view.mParent instanceof View) { + view = (View) view.mParent; + } else { + view = null; + } + } + } + } + if (mValidLayoutRequesters != null) { + // Clear flags throughout hierarchy, walking up from each flagged requester + for (int i = 0; i < numViewsRequestingLayout; ++i) { + View view = mLayoutRequesters.get(i); + while (view != null && + (view.mPrivateFlags & View.PFLAG_FORCE_LAYOUT) != 0) { + view.mPrivateFlags &= ~View.PFLAG_FORCE_LAYOUT; + if (view.mParent instanceof View) { + view = (View) view.mParent; + } else { + view = null; + } + } + } + // Process fresh layout requests, then measure and layout + mHandlingLayoutInLayoutRequest = true; + int numValidRequests = mValidLayoutRequesters.size(); + for (int i = 0; i < numValidRequests; ++i) { + mValidLayoutRequesters.get(i).requestLayout(); + } + measureHierarchy(host, lp, mView.getContext().getResources(), + desiredWindowWidth, desiredWindowHeight); + mInLayout = true; + host.layout(0, 0, host.getMeasuredWidth(), host.getMeasuredHeight()); + mHandlingLayoutInLayoutRequest = false; } - measureHierarchy(host, lp, mView.getContext().getResources(), - desiredWindowWidth, desiredWindowHeight); - // Now run layout one more time - mInLayout = true; - host.layout(0, 0, host.getMeasuredWidth(), host.getMeasuredHeight()); - mHandlingLayoutInLayoutRequest = false; mLayoutRequesters.clear(); } } finally { |