Android 自定义ViewGroup 实现FlowLayout，动态添加布局
参考以下两个博客：
Android 自定义ViewGroup 实战篇 -> 实现FlowLayout .
http://blog.csdn.net/lmj623565791/article/details/38352503
动态添加布局文件
http://download.csdn.net/detail/chenxiaofeng_/8887991
自定义的ViewGroup:FlowLayout.java
import java.util.ArrayList;
import java.util.List;
import android.content.Context;
import android.util.AttributeSet;
import android.util.Log;
import android.view.View;
import android.view.ViewGroup;
public class FlowLayout extends ViewGroup {
private static final String TAG = "FlowLayout";
public FlowLayout(Context context, AttributeSet attrs) {
super(context, attrs);
}
@Override
protected ViewGroup.LayoutParams generateLayoutParams(ViewGroup.LayoutParams p) {
return new MarginLayoutParams(p);
}
@Override
public ViewGroup.LayoutParams generateLayoutParams(AttributeSet attrs) {
return new MarginLayoutParams(getContext(), attrs);
}
@Override
protected ViewGroup.LayoutParams generateDefaultLayoutParams() {
return new MarginLayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
}
/**
* 负责设置子控件的测量模式和大小 根据所有子控件设置自己的宽和高
*/
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
// 获得它的父容器为它设置的测量模式和大小
int sizeWidth = MeasureSpec.getSize(widthMeasureSpec);
int sizeHeight = MeasureSpec.getSize(heightMeasureSpec);
int modeWidth = MeasureSpec.getMode(widthMeasureSpec);
int modeHeight = MeasureSpec.getMode(heightMeasureSpec);
Log.e(TAG, sizeWidth + "," + sizeHeight);
// 如果是warp_content情况下，记录宽和高
int width = 0;
int height = 0;
/**
* 记录每一行的宽度，width不断取最大宽度
*/
int lineWidth = 0;
/**
* 每一行的高度，累加至height
*/
int lineHeight = 0;
int cCount = getChildCount();
// 遍历每个子元素
for (int i = 0; i < cCount; i++) {
View child = getChildAt(i);
// 测量每一个child的宽和高
measureChild(child, widthMeasureSpec, heightMeasureSpec);
// 得到child的lp
MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams();
// 当前子空间实际占据的宽度
int childWidth = child.getMeasuredWidth() + lp.leftMargin + lp.rightMargin;
// 当前子空间实际占据的高度
int childHeight = child.getMeasuredHeight() + lp.topMargin + lp.bottomMargin;
/**
* 如果加入当前child，则超出最大宽度，则的到目前最大宽度给width，类加height 然后开启新行
*/
if (lineWidth + childWidth > sizeWidth) {
width = Math.max(lineWidth, childWidth);// 取最大的
lineWidth = childWidth; // 重新开启新行，开始记录
// 叠加当前高度，
height += lineHeight;
// 开启记录下一行的高度
lineHeight = childHeight;
} else
// 否则累加值lineWidth,lineHeight取最大高度
{
lineWidth += childWidth;
lineHeight = Math.max(lineHeight, childHeight);
}
// 如果是最后一个，则将当前记录的最大宽度和当前lineWidth做比较
if (i == cCount - 1) {
width = Math.max(width, lineWidth);
height += lineHeight;
}
}
setMeasuredDimension((modeWidth == MeasureSpec.EXACTLY) ? sizeWidth : width, (modeHeight == MeasureSpec.EXACTLY) ? sizeHeight : height);
}
/**
* 存储所有的View，按行记录
*/
private List> mAllViews = new ArrayList>();
/**
* 记录每一行的最大高度
*/
private List mLineHeight = new ArrayList();
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
mAllViews.clear();
mLineHeight.clear();
int width = getWidth();
int lineWidth = 0;
int lineHeight = 0;
// 存储每一行所有的childView
List lineViews = new ArrayList();
int cCount = getChildCount();
// 遍历所有的孩子
for (int i = 0; i < cCount; i++) {
View child = getChildAt(i);
MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams();
int childWidth = child.getMeasuredWidth();
int childHeight = child.getMeasuredHeight();
// 如果已经需要换行
if (childWidth + lp.leftMargin + lp.rightMargin + lineWidth > width) {
// 记录这一行所有的View以及最大高度
mLineHeight.add(lineHeight);
// 将当前行的childView保存，然后开启新的ArrayList保存下一行的childView
mAllViews.add(lineViews);
lineWidth = 0;// 重置行宽
lineViews = new ArrayList();
}
/**
* 如果不需要换行，则累加
*/
lineWidth += childWidth + lp.leftMargin + lp.rightMargin;
lineHeight = Math.max(lineHeight, childHeight + lp.topMargin + lp.bottomMargin);
lineViews.add(child);
}
// 记录最后一行
mLineHeight.add(lineHeight);
mAllViews.add(lineViews);
int left = 0;
int top = 0;
// 得到总行数
int lineNums = mAllViews.size();
for (int i = 0; i < lineNums; i++) {
// 每一行的所有的views
lineViews = mAllViews.get(i);
// 当前行的最大高度
lineHeight = mLineHeight.get(i);
Log.e(TAG, "第" + i + "行 ：" + lineViews.size() + " , " + lineViews);
Log.e(TAG, "第" + i + "行， ：" + lineHeight);
// 遍历当前行所有的View
for (int j = 0; j < lineViews.size(); j++) {
View child = lineViews.get(j);
if (child.getVisibility() == View.GONE) {
continue;
}
MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams();
// 计算childView的left,top,right,bottom
int lc = left + lp.leftMargin;
int tc = top + lp.topMargin;
int rc = lc + child.getMeasuredWidth();
int bc = tc + child.getMeasuredHeight();
Log.e(TAG, child + " , l = " + lc + " , t = " + t + " , r =" + rc + " , b = " + bc);
child.layout(lc, tc, rc, bc);
left += child.getMeasuredWidth() + lp.rightMargin + lp.leftMargin;
}
left = 0;
top += lineHeight;
}
}
}
MainActivity.java
使用方法
import java.util.ArrayList;
import android.app.Activity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup.MarginLayoutParams;
import android.widget.Button;
import android.widget.Toast;
import com.view.FlowGroupView;
public class MainActivity extends Activity {
ArrayList names = new ArrayList();
FlowLayout view;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setData();
view = (FlowLayout) LayoutInflater.from(this).inflate(R.layout.activity_main, null);
for (int i = 0; i < names.size(); i++) {
addTextView(names.get(i));
}
setContentView(view);
}
/**
* 动态添加布局
* @param str
*/
private void addTextView(String str) {
Button child = new Button(this);
MarginLayoutParams params = new MarginLayoutParams(MarginLayoutParams.WRAP_CONTENT, MarginLayoutParams.WRAP_CONTENT);
params.setMargins(15, 15, 15, 15);
child.setLayoutParams(params);
child.setText(str);
initEvents(child);
view.addView(child);
// 务必要加这句
view.requestLayout();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.action_settings) {
// 动态添加 view
addTextView(names.get((int) (Math.random() * names.size())));
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* 为每个view 添加点击事件
* @param tv
*/
private void initEvents(final Button tv) {
tv.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Toast.makeText(MainActivity.this, tv.getText().toString(), 0).show();
}
});
}
private void setData() {
names.add("1");
names.add("2");
names.add("3");
names.add("4");
names.add("5");
}
}
布局文件