今天把Android Studio 2.3 更新为了3.0 遇到一个蛋疼的问题

如图：

格式化完代码后发现不会自动换行了，看着真心不爽。

后来发现其实是设置问题,如图：

只要把这里打上√就可以了。

在此记录一下，希望可以帮到后面的小伙伴

补充知识：Android实现控件内自动换行（比如LinearLayout内部实现子控件换行 ）

一、创建类AntoLineUtil（换行操作主要在这里实现）

package com.inpor.fmctv.util;import android.content.Context;import android.content.res.TypedArray;import android.util.AttributeSet;import android.view.View;import android.view.ViewGroup;import com.inpor.fmctv.R;public class AntoLineUtil extends ViewGroup { /** * 子view左右间距 */ private int mHorizontalSpacing; /** * 子view上下行距离 */ private int mVerticalSpacing; private Context context; public AntoLineUtil(Context context) { this(context, null); this.context = context; } public AntoLineUtil(Context context, AttributeSet attrs) { this(context, attrs, 0); } public AntoLineUtil(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); if (attrs != null) { TypedArray array = context.obtainStyledAttributes(attrs, R.styleable.AntoLineUtil); mHorizontalSpacing = array.getDimensionPixelOffset( R.styleable.AntoLineUtil_horizontalSpacing, 0); mVerticalSpacing = array.getDimensionPixelOffset( R.styleable.AntoLineUtil_verticalSpacing, 0); array.recycle(); if (mHorizontalSpacing < 0) mHorizontalSpacing = 0; if (mVerticalSpacing < 0) mVerticalSpacing = 0; } } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { int width = MeasureSpec.getSize(widthMeasureSpec); int count = getChildCount(); for (int i = 0; i < count; i++) { measureChild(getChildAt(i), widthMeasureSpec, heightMeasureSpec); } int widthMode = MeasureSpec.getMode(widthMeasureSpec); if (widthMode != MeasureSpec.EXACTLY) { widthMeasureSpec = MeasureSpec.makeMeasureSpec( getAutoLinefeedWidth(width), widthMode); } int heightMode = MeasureSpec.getMode(heightMeasureSpec); if (heightMode != MeasureSpec.EXACTLY) { heightMeasureSpec = MeasureSpec.makeMeasureSpec( getAutoLinefeedHeight(width), heightMode); } super.onMeasure(widthMeasureSpec, heightMeasureSpec); } /** * 自动换行 计算需要的宽度 * * @param width 可用宽度 * @return 需要的宽度 */ private int getAutoLinefeedWidth(int width) { int totalWidth = getPaddingLeft() + getPaddingRight(); for (int i = 0; i < getChildCount(); i++) { if (i > 0) totalWidth += mHorizontalSpacing; View child = getChildAt(i); int childWidth = child.getMeasuredWidth(); totalWidth += childWidth; if (totalWidth >= width) { totalWidth = width; break; } } return totalWidth; } /** * 自动换行 计算需要的高度 * * @param width 可用宽度 * @return 需要的高度 */ private int getAutoLinefeedHeight(int width) { //一行最大可用宽度 int lineWidth = width - getPaddingLeft() - getPaddingRight(); //剩余可用宽度 int availableLineWidth = lineWidth; //需要的高度 int totalHeight = getPaddingTop() + getPaddingBottom(); int lineChildIndex = 0; //本行最大高度 int lineMaxHeight = 0; for (int i = 0; i < getChildCount(); i++) { View child = getChildAt(i); int childWidth = child.getMeasuredWidth(); int childHeight = child.getMeasuredHeight(); //这个child需要的宽度 如果不是第一位的 那么需要加上间距 //这里是用来判断需不需要换行 int needWidth = i == 0 ? childWidth : (childWidth + mHorizontalSpacing); //如果剩余可用宽度小于需要的长度 那么换行 if (availableLineWidth < needWidth) { totalHeight = totalHeight + lineMaxHeight; if (i > 0) totalHeight += mVerticalSpacing; availableLineWidth = lineWidth; lineMaxHeight = 0; lineChildIndex = 0; } //这个child需要的宽度 如果不是第一位的 那么需要加上间距 int realNeedWidth = lineChildIndex == 0 ? childWidth : (childWidth + mHorizontalSpacing); lineMaxHeight = Math.max(childHeight, lineMaxHeight); availableLineWidth = availableLineWidth - realNeedWidth; lineChildIndex++; } totalHeight = totalHeight + lineMaxHeight; return totalHeight; } @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { layout(); } private void layout() { int count = getChildCount(); int childLeft = getPaddingLeft(); int childTop = getPaddingTop(); int lineWidth = getMeasuredWidth() - getPaddingRight() - getPaddingLeft(); int availableLineWidth = lineWidth; int lineChildIndex = 0; //一行的最大高度 int lineMaxHeight = 0; for (int i = 0; i < count; i++) { View child = getChildAt(i); int childWidth = child.getMeasuredWidth(); int childHeight = child.getMeasuredHeight(); int needWidth = i == 0 ? childWidth : (childWidth + mHorizontalSpacing); if (availableLineWidth < needWidth) { availableLineWidth = lineWidth; childTop += lineMaxHeight; if (i > 0) childTop += mVerticalSpacing; lineMaxHeight = 0; childLeft = getPaddingLeft(); lineChildIndex = 0; } int realNeedWidth = lineChildIndex == 0 ? childWidth : (childWidth + mHorizontalSpacing); lineMaxHeight = Math.max(lineMaxHeight, childHeight); child.layout(childLeft + realNeedWidth - childWidth, childTop, childLeft + realNeedWidth, childTop + childHeight); availableLineWidth -= realNeedWidth; childLeft += realNeedWidth; lineChildIndex++; } } public int getHorizontalSpacing() { return mHorizontalSpacing; } public void setHorizontalSpacing(int horizontalSpacing) { mHorizontalSpacing = horizontalSpacing; } public int getVerticalSpacing() { return mVerticalSpacing; } public void setVerticalSpacing(int verticalSpacing) { mVerticalSpacing = verticalSpacing; }}

二、在values中的attrs.xml中添加以下代码（实现子控件的边距）：

<declare-styleable name="AntoLineUtil"> <attr name="horizontalSpacing" format="dimension"/> <attr name="verticalSpacing" format="dimension"/> </declare-styleable>

三、添加固定的xml布局父控件，事先写好，布局activity_video_preview.xml ：

<com.inpor.fmctv.util.AntoLineUtil android:id="@+id/camera_group" android:layout_width="@dimen/size_dp_630" android:layout_height="@dimen/size_dp_138" android:layout_marginTop="@dimen/size_dp_18" android:orientation="horizontal" app:horizontalSpacing="@dimen/size_dp_18" app:verticalSpacing="@dimen/size_dp_18"></com.inpor.fmctv.util.AntoLineUtil>

四、添加固定的xml布局子控件，事先写好，动态添加进去，布局item_camera_info.xml ：

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:id="@+id/video_preview_item" android:layout_width="@dimen/size_dp_198" android:layout_height="@dimen/size_dp_60" android:orientation="horizontal" android:paddingLeft="@dimen/size_dp_18" android:paddingRight="@dimen/size_dp_18" android:gravity="center_vertical" android:background="@color/textcolor_395878"> <TextView android:id="@+id/video_preview_item_tv" android:layout_width="@dimen/size_dp_120" android:layout_height="wrap_content" android:textSize="@dimen/size_sp_24" android:textColor="@color/white"/> <CheckBox android:id="@+id/video_previ" android:layout_width="@dimen/size_dp_24" android:layout_height="@dimen/size_dp_24" android:button="@null" android:background="@drawable/radio_button_select_ico" /></LinearLayout>

五、在其他方法中动态添加子控件：

AntoLineUtil cameraGroup = (AntoLineUitl) findViewById(R.id.camera_group); // 此处是找到父控件LinearLayoutfor (int i = 0; i<6; i++) { // 用以下方法将layout布局文件换成view LayoutInflater inflater = getLayoutInflater(); View view = inflater.inflate(R.layout.item_camera_info,null); TextView textView = view.findViewById(R.id.video_preview_item_tv); textView.setText("摄像头"+ (cameraId+1)); cameraGroup.addView(view);}

六、效果图：

以上这篇解决Android Studio xml 格式化不自动换行的问题就是小编分享给大家的全部内容了，希望能给大家一个参考，也希望大家多多支持。