attrArray.recycle();

}

//此視圖是否自行繪制

setWillNotDraw(false);

}

/**

*?負(fù)責(zé)設(shè)置子控件的測量模式和大小?根據(jù)所有子控件設(shè)置自己的寬和高

*/

@Override

protected?void?onMeasure(int?widthMeasureSpec,?int?heightMeasureSpec)?{

super.onMeasure(widthMeasureSpec,?heightMeasureSpec);

MLog.e(getClass().getName(),"onMeasure");

//?獲得它的父容器為它設(shè)置的測量模式和大小

int?sizeWidth?=?MeasureSpec.getSize(widthMeasureSpec);

int?sizeHeight?=?MeasureSpec.getSize(heightMeasureSpec);

int?modeWidth?=?MeasureSpec.getMode(widthMeasureSpec);

int?modeHeight?=?MeasureSpec.getMode(heightMeasureSpec);

//?如果是warp_content情況下,，記錄寬和高

int?width?=?0;

int?height?=?0;

//記錄每一行的寬度,，width不斷取最大寬度

int?lineWidth?=?0;

//每一行的高度,，累加至height

int?lineHeight?=?0;

int?count?=?getChildCount();

int?left?=?getPaddingLeft();

int?top?=?getPaddingTop();

//?遍歷每個子元素

for?(int?i?=?0;?i?<?count;?i++)?{

View?child?=?getChildAt(i);

if?(child.getVisibility()?==?GONE)

continue;

//?測量每一個child的寬和高

measureChild(child,?widthMeasureSpec,?heightMeasureSpec);

//?得到child的lp

ViewGroup.LayoutParams?lp?=?child.getLayoutParams();

//?當(dāng)前子空間實際占據(jù)的寬度

int?childWidth?=?child.getMeasuredWidth()?+?childHorizontalSpace;

//?當(dāng)前子空間實際占據(jù)的高度

int?childHeight?=?child.getMeasuredHeight()?+?childVerticalSpace;

if?(lp?!=?null?&&?lp?instanceof?MarginLayoutParams)?{

MarginLayoutParams?params?=?(MarginLayoutParams)?lp;

childWidth?+=?params.leftMargin?+?params.rightMargin;

childHeight?+=?params.topMargin?+?params.bottomMargin;

}

//如果加入當(dāng)前child，則超出最大寬度,，則的到目前最大寬度給width,，類加height?然后開啟新行

if?(lineWidth?+?childWidth?>?sizeWidth?-?getPaddingLeft()?-?getPaddingRight())?{

width?=?Math.max(lineWidth,?childWidth);//?取最大的

lineWidth?=?childWidth;?//?重新開啟新行，開始記錄

//?疊加當(dāng)前高度,，

height?+=?lineHeight;

//?開啟記錄下一行的高度

lineHeight?=?childHeight;

child.setTag(new?Location(left,?top?+?height,?childWidth

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?+?left?-?childHorizontalSpace,?height?+?child.getMeasuredHeight()?+?top));

}?else?{

//?否則累加值lineWidth,lineHeight取最大高度

child.setTag(new?Location(lineWidth?+?left,?top?+?height,?lineWidth?+?childWidth?-?childHorizontalSpace?+?left,?height?+?child.getMeasuredHeight()?+?top));

lineWidth?+=?childWidth;

lineHeight?=?Math.max(lineHeight,?childHeight);

}

}

width?=?Math.max(width,?lineWidth)?+?getPaddingLeft()?+?getPaddingRight();

height?+=?lineHeight;

sizeHeight?+=?getPaddingTop()?+?getPaddingBottom();

height?+=?getPaddingTop()?+?getPaddingBottom();

setMeasuredDimension((modeWidth??MeasureSpec.EXACTLY)???sizeWidth?:?width,?(modeHeight??MeasureSpec.EXACTLY)???sizeHeight?:?height);

}

/**

*?記錄子控件的坐標(biāo)

*/

public?class?Location?{

public?Location(int?left,?int?top,?int?right,?int?bottom)?{

this.left?=?left;

this.top?=?top;

this.right?=?right;

this.bottom?=?bottom;

}

public?int?left;

public?int?top;

public?int?right;

public?int?bottom;

}

//計算當(dāng)前View以及子View的位置

@Override

protected?void?onLayout(boolean?changed,?int?l,?int?t,?int?r,?int?b)?{

MLog.e(getClass().getName(),"onLayout");

//獲取子View個數(shù)

int?count?=?getChildCount();

for?(int?i?=?0;?i?<?count;?i++)?{

//獲取子View

View?child?=?getChildAt(i);

//判斷是否顯示

if?(child.getVisibility()?==?GONE)

continue;

//獲取子View的坐標(biāo)

Location?location?=?(Location)?child.getTag();

//設(shè)置子View位置

child.layout(location.left,?location.top,?location.right,?location.bottom);

}

}

@Override

protected?void?onSizeChanged(int?w,?int?h,?int?oldw,?int?oldh)?{

super.onSizeChanged(w,?h,?oldw,?oldh);

MLog.e(getClass().getName(),"onSizeChanged");

}

@Override

protected?void?onDraw(Canvas?canvas)?{

super.onDraw(canvas);

MLog.e(getClass().getName(),"onDraw");

}

}

2.使用自定義CustomLayout

<com.scc.demo.view.CustomLayout?xmlns:android="http://schemas./apk/res/android"

xmlns:custom="http://schemas./apk/res-auto"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:layout_margin="@dimen/dimen_20"

custom:horizontalSpace="10dp"

custom:verticalSpace="20dp">

<TextView

style="@style/TvStyle"

android:text="破陣子·為陳同甫賦壯詞以寄"?/>

<TextView

style="@style/TvStyle"

android:text="宋·辛棄疾"?/>

<TextView

style="@style/TvStyle"

android:text="醉里挑燈看劍"?/>

<TextView

style="@style/TvStyle"

android:text="夢回吹角連營"?/>

<TextView

style="@style/TvStyle"

android:text="八百里分麾下炙"?/>

<TextView

style="@style/TvStyle"

android:text="五十弦翻塞外聲"?/>

<TextView

style="@style/TvStyle"

android:text="沙場秋點兵"?/>

<TextView

style="@style/TvStyle"

android:text="馬作的盧飛快"?/>

<TextView

style="@style/TvStyle"

android:text="弓如霹靂弦驚(增加點長度)"?/>

<TextView

style="@style/TvStyle"

android:text="了卻君王天下事"?/>

<TextView

style="@style/TvStyle"

android:text="贏得生前身后名"?/>

<TextView

style="@style/TvStyle"

android:text="可憐白發(fā)生,！"?/>

</com.scc.demo.view.CustomLayout>

3.自定義屬性

在app/src/main/res/values/attrs.xml中添加屬性

<declare-styleable?name="CustomLayout">

<attr?name="verticalSpace"?format="dimension"?/>

<attr?name="horizontalSpace"?format="dimension"?/>

4.使用自定義屬性

• 在xml中使用

一定要添加：xmlns:test=”http://schemas./apk/res-auto”添加之后才能在xml中自定義屬性，如下代碼：

<com.scc.demo.view.CustomLayout?xmlns:android="http://schemas./apk/res/android"

xmlns:custom="http://schemas./apk/res-auto"

android:layout_width="match_parent"

android:layout_height="match_parent"

android:layout_margin="@dimen/dimen_20"

custom:horizontalSpace="10dp"

custom:verticalSpace="20dp">

</com.scc.demo.view.CustomLayout>

• 在代碼中使用

TypedArray?attrArray?=?context.obtainStyledAttributes(attrs,?R.styleable.CustomLayout);

if?(attrArray?!=?null)?{

//參數(shù)1：獲取xml中設(shè)置的參數(shù),；參數(shù)2：獲取失敗2使用參數(shù)作為默認(rèn)值

childHorizontalSpace?=?attrArray.getDimensionPixelSize(R.styleable.CustomLayout_horizontalSpace,?12);

childVerticalSpace?=?attrArray.getDimensionPixelSize(R.styleable.CustomLayout_verticalSpace,?12);

MLog.e(getClass().getName(),"HorizontalSpace:"+childHorizontalSpace+"|VerticalSpace："+childVerticalSpace);

//TypedArray對象池的大小默認(rèn)為5，使用時記得調(diào)用recyle()方法將不用的對象返回至對象池來達(dá)到重用的目的,。

attrArray.recycle();

}

寫到這里自定義ViewGroup基本完成,。

ViewGroup屬性