android自定义viewgroup之我也玩瀑布流
生活随笔
收集整理的這篇文章主要介紹了
android自定义viewgroup之我也玩瀑布流
小編覺得挺不錯的,現在分享給大家,幫大家做個參考.
先看效果圖吧,
繼上一篇《android自定義viewgroup實現等分格子布局》中實現的布局效果,這里稍微有些區別,每個格子的高度不規則,就是傳說的瀑布流布局,一般實現這種效果,要么用第三方控件,如果不是加載圖片還可以直接寫在xml中實現,不過代碼會很多的;
下面我重寫了viewgroup,實現 onMeasure,onLayout方法,動態設置每個布局的高度,這里有一個小的技巧,一般我們自定義的控件,嵌套在scrollview中顯示不 全,這個問題也糾結我一小會,不過當你打開scrollview的源碼,你會發現有一個地方,同時可以理解scrollview中嵌套 viewpager,gridview,listview時候會顯示不全的問題
下面是自定義viewgroup的全部代碼:
package com.allen.view;import com.allen.mygridlayout.R;import android.content.Context; import android.content.res.TypedArray; import android.util.AttributeSet; import android.view.View; import android.view.ViewGroup; import android.view.View.MeasureSpec;/*** @package:com.fumei.letao.views* @author:Allen* @email:jaylong1302@163.com* @data:2013年11月26日 下午8:39:51* @description:瀑布流視圖*/ public class WaterfullLayout extends ViewGroup {final String tag = "balance";// 列數int columns = 2;// 行數int rows = 0;// 邊距int margin = 10;// 子視圖數量int count = 0;private int mMaxChildWidth = 0;private int mMaxChildHeight = 0;public WaterfullLayout(Context context, AttributeSet attrs, int defStyle) {super(context, attrs, defStyle);if (attrs != null) {TypedArray a = getContext().obtainStyledAttributes(attrs,R.styleable.MyGridLayout);columns = a.getInteger(R.styleable.MyGridLayout_numColumns, 2);margin = (int) a.getInteger(R.styleable.MyGridLayout_itemMargin, 2);}}public WaterfullLayout(Context context, AttributeSet attrs) {super(context, attrs, 0);// TODO Auto-generated constructor stub }public WaterfullLayout(Context context) {super(context);// TODO Auto-generated constructor stub }@Overrideprotected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {mMaxChildWidth = 0;mMaxChildHeight = 0;count = getChildCount();if (count == 0) {super.onMeasure(widthMeasureSpec, heightMeasureSpec);return;}rows = count % columns == 0 ? count / columns : count / columns + 1;// 行數int top[] = new int[columns];for (int i = 0; i < rows; i++) {// 遍歷行for (int j = 0; j < columns; j++) {// 遍歷每一行的元素View child = this.getChildAt(i * columns + j);if (child == null)break;ViewGroup.LayoutParams lp = child.getLayoutParams();if (child.getVisibility() == GONE) {continue;}child.measure(MeasureSpec.makeMeasureSpec(MeasureSpec.getSize(widthMeasureSpec),MeasureSpec.EXACTLY), MeasureSpec.makeMeasureSpec(lp.height, MeasureSpec.AT_MOST));top[j] += lp.height + margin;mMaxChildWidth = Math.max(mMaxChildWidth,child.getMeasuredWidth());}}setMeasuredDimension(resolveSize(mMaxChildWidth, widthMeasureSpec),resolveSize(getMax(top) + margin, heightMeasureSpec));}@Overrideprotected void onLayout(boolean changed, int l, int t, int r, int b) {// TODO Auto-generated method stubint height = b - t;// 布局區域高度int width = r - l;// 布局區域寬度if (count == 0)return;int gridW = (width - margin * (columns + 1)) / columns;// 格子寬度int gridH = 0;// 格子高度int left = 0;int top[] = new int[columns];for (int i = 0; i < rows; i++) {// 遍歷行for (int j = 0; j < columns; j++) {// 遍歷每一行的元素View child = this.getChildAt(i * columns + j);if (child == null)return;ViewGroup.LayoutParams lp = child.getLayoutParams();child.measure(MeasureSpec.makeMeasureSpec(gridW,MeasureSpec.EXACTLY), MeasureSpec.makeMeasureSpec(lp.height, MeasureSpec.AT_MOST));// 如果最后有一個對其的標志,為了底部對其if (child.getTag() != null && child.getTag().equals(tag)) {child.measure(MeasureSpec.makeMeasureSpec(gridW,MeasureSpec.EXACTLY), MeasureSpec.makeMeasureSpec(getMax(top) - top[j], MeasureSpec.EXACTLY));gridH = getMax(top) - top[j];left = j * gridW + margin * (j + 1);child.layout(left, top[j] + margin, left + gridW, top[j]+ gridH);break;}gridH = lp.height;left = j * gridW + margin * (j + 1);top[j] += margin;child.layout(left, top[j], left + gridW, top[j] + gridH);top[j] += gridH;}}}/** 計算整體布局高度,為了在嵌套在scrollview中能顯示出來 */private int getMax(int array[]) {int max = array[0];for (int i = 0; i < array.length; i++) {if (max < array[i])max = array[i];}return max;}}
轉載于:https://www.cnblogs.com/Free-Thinker/p/3644292.html
總結
以上是生活随笔為你收集整理的android自定义viewgroup之我也玩瀑布流的全部內容,希望文章能夠幫你解決所遇到的問題。
- 上一篇: SQL求解两个时间差
- 下一篇: 概率dp专场