Android(安卓)Bugs——RecyclerView.Adapter java.lang.IllegalStateException: The specified child already h

Error：

java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child’s parent first.

原因：

这个问题的原因很简单，该异常表示已经存在父布局，不能再添加父布局。导致该异常的代码可能是：
View view = LayoutInflater.from(getContext()).inflate(R.layout.news_item, parent);

解决方法：

在 inflate() 方法上加入第三个参数，指定为 false 即可。

通常情况下，我们在获取View的时候一般代码都是：

View view = LayoutInflater.from(getContext()).inflate(R.layout.news_item, parent，false);

注意第三个参数为false，所以在获取View的时候并不会把parent设置为View的父布局。默认情况下，如果你不设置inflate的第三个参数，这个参数默认为parent！=null的值。
源码如下：

 public View inflate(@LayoutRes int resource, @Nullable ViewGroup root) {        return inflate(resource, root, root != null);    } public View inflate(XmlPullParser parser, @Nullable ViewGroup root, boolean attachToRoot) {        synchronized (mConstructorArgs) {            Trace.traceBegin(Trace.TRACE_TAG_VIEW, "inflate");            final Context inflaterContext = mContext;            final AttributeSet attrs = Xml.asAttributeSet(parser);            Context lastContext = (Context) mConstructorArgs[0];            mConstructorArgs[0] = inflaterContext;            View result = root;            try {                // Look for the root node.                int type;                while ((type = parser.next()) != XmlPullParser.START_TAG &&                        type != XmlPullParser.END_DOCUMENT) {                    // Empty                }                if (type != XmlPullParser.START_TAG) {                    throw new InflateException(parser.getPositionDescription()                            + ": No start tag found!");                }                final String name = parser.getName();                if (DEBUG) {                    System.out.println("**************************");                    System.out.println("Creating root view: "                            + name);                    System.out.println("**************************");                }                if (TAG_MERGE.equals(name)) {                    if (root == null || !attachToRoot) {                        throw new InflateException(" can be used only with a valid "                                + "ViewGroup root and attachToRoot=true");                    }                    rInflate(parser, root, inflaterContext, attrs, false);                } else {                    // Temp is the root view that was found in the xml                    final View temp = createViewFromTag(root, name, inflaterContext, attrs);                    ViewGroup.LayoutParams params = null;                    if (root != null) {                        if (DEBUG) {                            System.out.println("Creating params from root: " +                                    root);                        }                        // Create layout params that match root, if supplied                        params = root.generateLayoutParams(attrs);                        if (!attachToRoot) {                            // Set the layout params for temp if we are not                            // attaching. (If we are, we use addView, below)                            temp.setLayoutParams(params);                        }                    }                    if (DEBUG) {                        System.out.println("-----> start inflating children");                    }                    // Inflate all children under temp against its context.                    rInflateChildren(parser, temp, attrs, true);                    if (DEBUG) {                        System.out.println("-----> done inflating children");                    }                    // We are supposed to attach all the views we found (int temp)                    // to root. Do that now.                    if (root != null && attachToRoot) {                        root.addView(temp, params);                    }                    // Decide whether to return the root that was passed in or the                    // top view found in xml.                    if (root == null || !attachToRoot) {                        result = temp;                    }                }            } catch (XmlPullParserException e) {                final InflateException ie = new InflateException(e.getMessage(), e);                ie.setStackTrace(EMPTY_STACK_TRACE);                throw ie;            } catch (Exception e) {                final InflateException ie = new InflateException(parser.getPositionDescription()                        + ": " + e.getMessage(), e);                ie.setStackTrace(EMPTY_STACK_TRACE);                throw ie;            } finally {                // Don't retain static reference on context.                mConstructorArgs[0] = lastContext;                mConstructorArgs[1] = null;                Trace.traceEnd(Trace.TRACE_TAG_VIEW);            }            return result;        }    }

相信读完源码，大家就会对这个异常晃人大悟了。

Error：

原因：

解决方法：

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