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import android.content.Context;
import android.content.res.TypedArray;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
import java.util.ArrayList;
import java.util.List;
public class FlowLayout extends ViewGroup {
private static final String TAG = "FlowLayout";
protected List> mAllViews = new ArrayList>();
protected List mLineHeight = new ArrayList();
private String mGravity;
public FlowLayout(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.TagFlowLayout);
mGravity = ta.getString(R.styleable.TagFlowLayout_gravity);
if (mGravity == null)
mGravity = getResources().getString(R.string.gravity_left);
ta.recycle();
}public FlowLayout(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}public FlowLayout(Context context) {
this(context, null);
}@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int sizeWidth = MeasureSpec.getSize(widthMeasureSpec);
int modeWidth = MeasureSpec.getMode(widthMeasureSpec);
int sizeHeight = MeasureSpec.getSize(heightMeasureSpec);
int modeHeight = MeasureSpec.getMode(heightMeasureSpec);
// wrap_content
int width = 0;
int height = 0;
int lineWidth = 0;
int lineHeight = 0;
int cCount = getChildCount();
for (int i = 0;
i < cCount;
i++) {
View child = getChildAt(i);
if (child.getVisibility() == View.GONE) {
if (i == cCount - 1) {
width = Math.max(lineWidth, width);
height += lineHeight;
}
continue;
}
measureChild(child, widthMeasureSpec, heightMeasureSpec);
MarginLayoutParams lp = (MarginLayoutParams) child
.getLayoutParams();
int childWidth = child.getMeasuredWidth() + lp.leftMargin
+ lp.rightMargin;
int childHeight = child.getMeasuredHeight() + lp.topMargin
+ lp.bottomMargin;
if (lineWidth + childWidth > sizeWidth - getPaddingLeft() - getPaddingRight()) {
width = Math.max(width, lineWidth);
lineWidth = childWidth;
height += lineHeight;
lineHeight = childHeight;
} else {
lineWidth += childWidth;
lineHeight = Math.max(lineHeight, childHeight);
}
if (i == cCount - 1) {
width = Math.max(lineWidth, width);
height += lineHeight;
}
}
setMeasuredDimension(
//
modeWidth == MeasureSpec.EXACTLY ? sizeWidth : width + getPaddingLeft() + getPaddingRight(),
modeHeight == MeasureSpec.EXACTLY ? sizeHeight : height + getPaddingTop() + getPaddingBottom()//
);
}@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;
List lineViews = new ArrayList();
int cCount = getChildCount();
for (int i = 0;
i < cCount;
i++) {
View child = getChildAt(i);
if (child.getVisibility() == View.GONE) continue;
MarginLayoutParams lp = (MarginLayoutParams) child
.getLayoutParams();
int childWidth = child.getMeasuredWidth();
int childHeight = child.getMeasuredHeight();
if (childWidth + lineWidth + lp.leftMargin + lp.rightMargin > width - getPaddingLeft() - getPaddingRight()) {
mLineHeight.add(lineHeight);
mAllViews.add(lineViews);
lineWidth = 0;
lineHeight = childHeight + lp.topMargin + lp.bottomMargin;
lineViews = new ArrayList();
}
lineWidth += childWidth + lp.leftMargin + lp.rightMargin;
lineHeight = Math.max(lineHeight, childHeight + lp.topMargin
+ lp.bottomMargin);
lineViews.add(child);
}
mLineHeight.add(lineHeight);
mAllViews.add(lineViews);
int left = getPaddingLeft();
int top = getPaddingTop();
int lineNum = mAllViews.size();
for (int i = 0;
i < lineNum;
i++) {
lineViews = mAllViews.get(i);
lineHeight = mLineHeight.get(i);
left = getStartLeft(lineViews);
for (int j = 0;
j < lineViews.size();
j++) {
View child = lineViews.get(j);
if (child.getVisibility() == View.GONE) {
continue;
}MarginLayoutParams lp = (MarginLayoutParams) child
.getLayoutParams();
int lc = left + lp.leftMargin;
int tc = top + lp.topMargin;
int rc = lc + child.getMeasuredWidth();
int bc = tc + child.getMeasuredHeight();
child.layout(lc, tc, rc, bc);
left += child.getMeasuredWidth() + lp.leftMargin
+ lp.rightMargin;
}
top += lineHeight;
}}private int getStartLeft(List lineViews) {
int left = getPaddingLeft();
int needWidth = 0;
for (int j = 0;
j < lineViews.size();
j++) {
View child = lineViews.get(j);
if (child.getVisibility() == View.GONE) {
continue;
}MarginLayoutParams lp = (MarginLayoutParams) child
.getLayoutParams();
needWidth += child.getMeasuredWidth() + lp.leftMargin
+ lp.rightMargin;
}needWidth += getPaddingLeft() + getPaddingRight();
if (mGravity.equals(getResources().getString(R.string.gravity_center))) {
if (getMeasuredWidth() > needWidth) {
left += (getMeasuredWidth() - needWidth) / 2;
}
} else if (mGravity.equals(getResources().getString(R.string.gravity_right))) {
if (getMeasuredWidth() > needWidth) {
left += getMeasuredWidth() - needWidth;
}
}
return left;
}@Override
public LayoutParams generateLayoutParams(AttributeSet attrs) {
return new MarginLayoutParams(getContext(), attrs);
}@Override
protected LayoutParams generateDefaultLayoutParams() {
return new MarginLayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
}@Override
protected LayoutParams generateLayoutParams(LayoutParams p) {
return new MarginLayoutParams(p);
}
}
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