Android——自定义LinearLayout自动换行，TextView垂直排列。

自定义线性布局在xml中自定换行，比如你在项目中用到LinearLayout，设置水平排列android:orientation=”horizontal”，包裹button或者是TextView，但是不同分辨率的手机，不知道一行能放多少个Button，所以要使用到自动换行的LinearLayout，不多说，贴代码：

package com.ds.platform.view;import android.content.Context;import android.util.AttributeSet;import android.view.View;import android.widget.LinearLayout;import java.util.Hashtable;/** * @author: Allen * @date: 2017/3/13 * @description: 自定义linearLayout 自动换行 */public class MyLinearLayout extends LinearLayout {    int mLeft, mRight, mTop, mBottom;    Hashtable map = new Hashtable();    public MyLinearLayout(Context context) {        super(context);    }    public MyLinearLayout(Context context, int horizontalSpacing, int verticalSpacing) {        super(context);    }    public MyLinearLayout(Context context, AttributeSet attrs) {        super(context, attrs);    }    @Override    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {        int mWidth = MeasureSpec.getSize(widthMeasureSpec);        int mCount = getChildCount();        int mX = 0;        int mY = 0;        mLeft = 0;        mRight = 0;        mTop = 5;        mBottom = 0;        int j = 0;        View lastview = null;        for (int i = 0; i < mCount; i++) {            final View child = getChildAt(i);            child.measure(MeasureSpec.UNSPECIFIED, MeasureSpec.UNSPECIFIED);            // 此处增加onlayout中的换行判断，用于计算所需的高度            int childw = child.getMeasuredWidth();            int childh = child.getMeasuredHeight();            mX += childw; // 将每次子控件宽度进行统计叠加，如果大于设定的高度则需要换行，高度即Top坐标也需重新设置            Position position = new Position();            mLeft = getPosition(i - j, i);            mRight = mLeft + child.getMeasuredWidth();            if (mX >= mWidth) {                mX = childw;                mY += childh;                j = i;                mLeft = 0;                mRight = mLeft + child.getMeasuredWidth();                mTop = mY + 5;                // PS：如果发现高度还是有问题就得自己再细调了            }            mBottom = mTop + child.getMeasuredHeight();            mY = mTop; // 每次的高度必须记录 否则控件会叠加到一起            position.left = mLeft;            position.top = mTop + 5;            position.right = mRight;            position.bottom = mBottom;            map.put(child, position);        }        setMeasuredDimension(mWidth, mBottom);    }    @Override    protected LayoutParams generateDefaultLayoutParams() {        return new LayoutParams(0, 0); // default of 1px spacing    }    @Override    protected void onLayout(boolean changed, int l, int t, int r, int b) {        int count = getChildCount();        for (int i = 0; i < count; i++) {            View child = getChildAt(i);            Position pos = (Position) map.get(child);            if (pos != null) {                child.layout(pos.left, pos.top, pos.right, pos.bottom);            } else {            }        }    }    private class Position {        int left, top, right, bottom;    }    public int getPosition(int IndexInRow, int childIndex) {        if (IndexInRow > 0) {            return getPosition(IndexInRow - 1, childIndex - 1) + getChildAt(childIndex - 1).getMeasuredWidth() + 5;        }        return getPaddingLeft();    }}

然后在布局里面一样使用：

<com.ds.platform.view.MyLinearLayout        android:id="@+id/side_slip"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:orientation="horizontal">    </com.ds.platform.view.MyLinearLayout>

注意这边一定要设置android:orientation=”horizontal”，否则不显示。

TextView垂直排列，代码如下：

package com.ds.platform.view;import android.content.Context;import android.graphics.Canvas;import android.util.AttributeSet;import android.view.Gravity;import android.widget.TextView;/** * @author: Allen * @date: 2017/3/23 * @description: 垂直排列文字 */public class MyTextView extends TextView {    final boolean topDown;    public MyTextView(Context context, AttributeSet attrs) {        super(context, attrs);        final int gravity = getGravity();        if (Gravity.isVertical(gravity) && (gravity & Gravity.VERTICAL_GRAVITY_MASK) == Gravity.BOTTOM) {            setGravity((gravity & Gravity.HORIZONTAL_GRAVITY_MASK) | Gravity.TOP);            topDown = false;        } else            topDown = true;    }    @Override    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {        super.onMeasure(heightMeasureSpec, widthMeasureSpec);        setMeasuredDimension(getMeasuredHeight(), getMeasuredWidth());    }    @Override    protected boolean setFrame(int l, int t, int r, int b) {        return super.setFrame(l, t, l + (b - t), t + (r - l));    }    @Override    public void draw(Canvas canvas) {        if (topDown) {            canvas.translate(getHeight(), 0);            canvas.rotate(90);        } else {            canvas.translate(0, getWidth());            canvas.rotate(-90);        }        canvas.clipRect(0, 0, getWidth(), getHeight(), android.graphics.Region.Op.REPLACE);        super.draw(canvas);    }}

用法跟普通TextView一样，这边给自己做一个笔记。