Java ViewTreeObserver.removeOnPreDrawListener方法代碼示例

import android.view.ViewTreeObserver; //導入方法依賴的package包/類
@Override public boolean onPreDraw() {
  ImageView target = this.target.get();
  if (target == null) {
    return true;
  }

  ViewTreeObserver vto = target.getViewTreeObserver();
  if (!vto.isAlive()) {
    return true;
  }

  int width = target.getWidth();
  int height = target.getHeight();

  if (width <= 0 || height <= 0 || target.isLayoutRequested()) {
    return true;
  }

  target.removeOnAttachStateChangeListener(this);
  vto.removeOnPreDrawListener(this);
  this.target.clear();

  this.creator.unfit().resize(width, height).into(target, callback);
  return true;
}
 

import android.view.ViewTreeObserver; //導入方法依賴的package包/類
void cancel() {
  creator.clearTag();
  callback = null;

  ImageView target = this.target.get();
  if (target == null) {
    return;
  }
  this.target.clear();

  target.removeOnAttachStateChangeListener(this);

  ViewTreeObserver vto = target.getViewTreeObserver();
  if (vto.isAlive()) {
    vto.removeOnPreDrawListener(this);
  }
}
 

import android.view.ViewTreeObserver; //導入方法依賴的package包/類
void clearCallbacksAndListener() {
  // Keep a reference to the layout listener and remove it here
  // rather than having the observer remove itself because the observer
  // we add the listener to will be almost immediately merged into
  // another observer and will therefore never be alive. If we instead
  // keep a reference to the listener and remove it here, we get the
  // current view tree observer and should succeed.
  ViewTreeObserver observer = view.getViewTreeObserver();
  if (observer.isAlive()) {
    observer.removeOnPreDrawListener(layoutListener);
  }
  layoutListener = null;
  cbs.clear();
}
 

import android.view.ViewTreeObserver; //導入方法依賴的package包/類
void clearCallbacksAndListener() {
  // Keep a reference to the layout attachStateListener and remove it here
  // rather than having the observer remove itself because the observer
  // we add the attachStateListener to will be almost immediately merged into
  // another observer and will therefore never be alive. If we instead
  // keep a reference to the attachStateListener and remove it here, we get the
  // current view tree observer and should succeed.
  ViewTreeObserver observer = view.getViewTreeObserver();
  if (observer.isAlive()) {
    observer.removeOnPreDrawListener(layoutListener);
  }
  layoutListener = null;
  cbs.clear();
}
 

import android.view.ViewTreeObserver; //導入方法依賴的package包/類
@Override
protected void onDetachedFromWindow() {
    if (mGlobalListenersAdded) {
        ViewTreeObserver observer = getViewTreeObserver();
        observer.removeOnScrollChangedListener(mScrollChangedListener);
        observer.removeOnPreDrawListener(mDrawListener);
        mGlobalListenersAdded = false;
    }
    mRequestedVisible = false;
    updateWindow(false, false);
    mLayout.token = null;
    super.onDetachedFromWindow();
}
 

import android.view.ViewTreeObserver; //導入方法依賴的package包/類
@Override
public boolean onPreDraw() {
    if (!hasRef()) {
        return false;
    }

    final ViewTreeObserver observer = getWeakRef().get().getViewTreeObserver();
    if (observer == null || !observer.isAlive()) {
        return false;
    }

    observer.removeOnPreDrawListener(this);
    return onPreDraw(getWeakRef().get());
}
 

import android.view.ViewTreeObserver; //導入方法依賴的package包/類
@Override
public void onDetachedFromWindow() {
  super.onDetachedFromWindow();
      resetTouchBehaviors(false);
  if (mNeedsPreDrawListener && mOnPreDrawListener != null) {
    final ViewTreeObserver vto = getViewTreeObserver();
    vto.removeOnPreDrawListener(mOnPreDrawListener);
  }
  if (mNestedScrollingTarget != null) {
    onStopNestedScroll(mNestedScrollingTarget);
  }
  mIsAttachedToWindow = false;
}
 

import android.view.ViewTreeObserver; //導入方法依賴的package包/類
/**
   * Remove the pre-draw listener if we're attached to a window and mark that we currently
   * do not need it when attached.
 */
void removePreDrawListener() {
  if (mIsAttachedToWindow) {
    if (mOnPreDrawListener != null) {
      final ViewTreeObserver vto = getViewTreeObserver();
      vto.removeOnPreDrawListener(mOnPreDrawListener);
    }
  }
  mNeedsPreDrawListener = false;
}