FlowLayout流式布局

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public class TagFlowLayout extends FlowLayout
        implements TagAdapter.OnDataChangedListener {
    private TagAdapter mTagAdapter;
    private int mSelectedMax = -1;//-1为不限制数量
    private static final String TAG = "TagFlowLayout";
    private Set<Integer> mSelectedView = new HashSet<Integer>();
    private OnSelectListener mOnSelectListener;
    private OnTagClickListener mOnTagClickListener;
    public interface OnSelectListener {
        void onSelected(Set<Integer> selectPosSet);
    }

    public interface OnTagClickListener {
        boolean onTagClick(View view, int position, FlowLayout parent);
    }

    public TagFlowLayout(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.TagFlowLayout);
        mSelectedMax = ta.getInt(R.styleable.TagFlowLayout_max_select, -1);
        ta.recycle();
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        int cCount = getChildCount();
        for (int i = 0; i < cCount; i++) {
            TagView tagView = (TagView) getChildAt(i);
            if (tagView.getVisibility() == View.GONE) {
                continue;
            }
            if (tagView.getTagView().getVisibility() == View.GONE) {
                tagView.setVisibility(View.GONE);
            }
        }
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }


    public void setOnSelectListener(OnSelectListener onSelectListener) {
        mOnSelectListener = onSelectListener;
    }
    public void setOnTagClickListener(OnTagClickListener onTagClickListener) {
        mOnTagClickListener = onTagClickListener;
    }

    public void setAdapter(TagAdapter adapter) {
        mTagAdapter = adapter;
        mTagAdapter.setOnDataChangedListener(this);
        mSelectedView.clear();
        changeAdapter();
    }
    @SuppressWarnings("ResourceType")
    private void changeAdapter() {
        removeAllViews();
        TagAdapter adapter = mTagAdapter;
        TagView tagViewContainer = null;
        HashSet preCheckedList = mTagAdapter.getPreCheckedList();
        for (int i = 0; i < adapter.getCount(); i++) {
            View tagView = adapter.getView(this, i, adapter.getItem(i));

            tagViewContainer = new TagView(getContext());
            tagView.setDuplicateParentStateEnabled(true);
            if (tagView.getLayoutParams() != null) {
                tagViewContainer.setLayoutParams(tagView.getLayoutParams());


            } else {
                MarginLayoutParams lp = new MarginLayoutParams(
                        LayoutParams.WRAP_CONTENT,
                        LayoutParams.WRAP_CONTENT);
                lp.setMargins(dip2px(getContext(), 5),
                        dip2px(getContext(), 5),
                        dip2px(getContext(), 5),
                        dip2px(getContext(), 5));
                tagViewContainer.setLayoutParams(lp);
            }
            LayoutParams lp = new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
            tagView.setLayoutParams(lp);
            tagViewContainer.addView(tagView);
            addView(tagViewContainer);

            if (preCheckedList.contains(i)) {
                setChildChecked(i, tagViewContainer);
            }

            if (mTagAdapter.setSelected(i, adapter.getItem(i))) {
                setChildChecked(i, tagViewContainer);
            }
            tagView.setClickable(false);
            final TagView finalTagViewContainer = tagViewContainer;
            final int position = i;
            tagViewContainer.setOnClickListener(new OnClickListener() {
                @Override
                public void onClick(View v) {
                    doSelect(finalTagViewContainer, position);
                    if (mOnTagClickListener != null) {
                        mOnTagClickListener.onTagClick(finalTagViewContainer, position,
                                TagFlowLayout.this);
                    }
                }
            });
        }
        mSelectedView.addAll(preCheckedList);
    }

    public void setMaxSelectCount(int count) {
        if (mSelectedView.size() > count) {
            Log.w(TAG, "you has already select more than " + count + " views , so it will be clear .");
            mSelectedView.clear();
        }
        mSelectedMax = count;
    }

    public Set<Integer> getSelectedList() {
        return new HashSet<Integer>(mSelectedView);
    }

    private void setChildChecked(int position, TagView view) {
        view.setChecked(true);
        mTagAdapter.onSelected(position, view.getTagView());
    }

    private void setChildUnChecked(int position, TagView view) {
        view.setChecked(false);
        mTagAdapter.unSelected(position, view.getTagView());
    }

    private void doSelect(TagView child, int position) {
        if (!child.isChecked()) {
            //处理max_select=1的情况
            if (mSelectedMax == 1 && mSelectedView.size() == 1) {
                Iterator<Integer> iterator = mSelectedView.iterator();
                Integer preIndex = iterator.next();
                TagView pre = (TagView) getChildAt(preIndex);
                setChildUnChecked(preIndex, pre);
                setChildChecked(position, child);

                mSelectedView.remove(preIndex);
                mSelectedView.add(position);
            } else {
                if (mSelectedMax > 0 && mSelectedView.size() >= mSelectedMax) {
                    return;
                }
                setChildChecked(position, child);
                mSelectedView.add(position);
            }
        } else {
            setChildUnChecked(position, child);
            mSelectedView.remove(position);
        }
        if (mOnSelectListener != null) {
            mOnSelectListener.onSelected(new HashSet<Integer>(mSelectedView));
        }
    }
    public TagAdapter getAdapter() {
        return mTagAdapter;
    }
    private static final String KEY_CHOOSE_POS = "key_choose_pos";
    private static final String KEY_DEFAULT = "key_default";
    @Override
    protected Parcelable onSaveInstanceState() {
        Bundle bundle = new Bundle();
        bundle.putParcelable(KEY_DEFAULT, super.onSaveInstanceState());

        String selectPos = "";
        if (mSelectedView.size() > 0) {
            for (int key : mSelectedView) {
                selectPos += key + "|";
            }
            selectPos = selectPos.substring(0, selectPos.length() - 1);
        }
        bundle.putString(KEY_CHOOSE_POS, selectPos);
        return bundle;
    }
    @Override
    protected void onRestoreInstanceState(Parcelable state) {
        if (state instanceof Bundle) {
            Bundle bundle = (Bundle) state;
            String mSelectPos = bundle.getString(KEY_CHOOSE_POS);
            if (!TextUtils.isEmpty(mSelectPos)) {
                String[] split = mSelectPos.split("\|");
                for (String pos : split) {
                    int index = Integer.parseInt(pos);
                    mSelectedView.add(index);

                    TagView tagView = (TagView) getChildAt(index);
                    if (tagView != null) {
                        setChildChecked(index, tagView);
                    }
                }

            }
            super.onRestoreInstanceState(bundle.getParcelable(KEY_DEFAULT));
            return;
        }
        super.onRestoreInstanceState(state);
    }
    @Override
    public void onChanged() {
        mSelectedView.clear();
        changeAdapter();
    }
    public static int dip2px(Context context, float dpValue) {
        final float scale = context.getResources().getDisplayMetrics().density;
        return (int) (dpValue * scale + 0.5f);
    }
}

基类流式布局

public class FlowLayout extends ViewGroup {
    private static final String TAG = "FlowLayout";
    private static final int LEFT = -1;
    private static final int CENTER = 0;
    private static final int RIGHT = 1;

    protected List<List<View>> mAllViews = new ArrayList<List<View>>();
    protected List<Integer> mLineHeight = new ArrayList<Integer>();
    protected List<Integer> mLineWidth = new ArrayList<Integer>();
    private int mGravity;
    private List<View> lineViews = new ArrayList<>();

    public FlowLayout(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        TypedArray ta = context.obtainStyledAttributes(attrs, R.styleable.TagFlowLayout);
        mGravity = ta.getInt(R.styleable.TagFlowLayout_tag_gravity, LEFT);
        int layoutDirection = TextUtilsCompat.getLayoutDirectionFromLocale(Locale.getDefault());
        if (layoutDirection == LayoutDirection.RTL) {
            if (mGravity == LEFT) {
                mGravity = RIGHT;
            } else {
                mGravity = 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();
        mLineWidth.clear();
        lineViews.clear();

        int width = getWidth();

        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) 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);
                mLineWidth.add(lineWidth);

                lineWidth = 0;
                lineHeight = childHeight + lp.topMargin + lp.bottomMargin;
                lineViews = new ArrayList<View>();
            }
            lineWidth += childWidth + lp.leftMargin + lp.rightMargin;
            lineHeight = Math.max(lineHeight, childHeight + lp.topMargin
                    + lp.bottomMargin);
            lineViews.add(child);

        }
        mLineHeight.add(lineHeight);
        mLineWidth.add(lineWidth);
        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);

            // set gravity
            int currentLineWidth = this.mLineWidth.get(i);
            switch (this.mGravity) {
                case LEFT:
                    left = getPaddingLeft();
                    break;
                case CENTER:
                    left = (width - currentLineWidth) / 2 + getPaddingLeft();
                    break;
                case RIGHT:
                    //  适配了rtl，需要补偿一个padding值
                    left = width - (currentLineWidth + getPaddingLeft()) - getPaddingRight();
                    //  适配了rtl，需要把lineViews里面的数组倒序排
                    Collections.reverse(lineViews);
                    break;
            }

            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;
        }

    }

    @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);
    }
}

adapter基类

package com.example.myapplication.data;

import android.util.Log;
import android.view.View;


import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

public abstract class TagAdapter<T> {
    private List<T> mTagDatas;
    private OnDataChangedListener mOnDataChangedListener;
    @Deprecated
    private HashSet<Integer> mCheckedPosList = new HashSet<Integer>();

    public TagAdapter(List<T> datas) {
        mTagDatas = datas;
    }

    @Deprecated
    public TagAdapter(T[] datas) {
        mTagDatas = new ArrayList<T>(Arrays.asList(datas));
    }

    interface OnDataChangedListener {
        void onChanged();
    }

    void setOnDataChangedListener(OnDataChangedListener listener) {
        mOnDataChangedListener = listener;
    }

    @Deprecated
    public void setSelectedList(int... poses) {
        Set<Integer> set = new HashSet<>();
        for (int pos : poses) {
            set.add(pos);
        }
        setSelectedList(set);
    }

    @Deprecated
    public void setSelectedList(Set<Integer> set) {
        mCheckedPosList.clear();
        if (set != null) {
            mCheckedPosList.addAll(set);
        }
        notifyDataChanged();
    }

    @Deprecated
    HashSet<Integer> getPreCheckedList() {
        return mCheckedPosList;
    }


    public int getCount() {
        return mTagDatas == null ? 0 : mTagDatas.size();
    }

    public void notifyDataChanged() {
        if (mOnDataChangedListener != null)
            mOnDataChangedListener.onChanged();
    }

    public T getItem(int position) {
        return mTagDatas.get(position);
    }

    public abstract View getView(FlowLayout parent, int position, T t);


    public void onSelected(int position, View view){
    }

    public void unSelected(int position, View view){
    }

    public boolean setSelected(int position, T t) {
        return false;
    }


}

TagView 类

package com.example.myapplication.data;

import android.content.Context;
import android.view.View;
import android.widget.Checkable;
import android.widget.FrameLayout;

/**
 * Created by zhy on 15/9/10.
 */
public class TagView extends FrameLayout implements Checkable
{
    private boolean isChecked;
    private static final int[] CHECK_STATE = new int[]{android.R.attr.state_checked};
    public TagView(Context context)
    {
        super(context);
    }
    public View getTagView()
    {
        return getChildAt(0);
    }

    @Override
    public int[] onCreateDrawableState(int extraSpace)
    {
        int[] states = super.onCreateDrawableState(extraSpace + 1);
        if (isChecked())
        {
            mergeDrawableStates(states, CHECK_STATE);
        }
        return states;
    }

    @Override
    public void setChecked(boolean checked)
    {
        if (this.isChecked != checked)
        {
            this.isChecked = checked;
            refreshDrawableState();
        }
    }
    @Override
    public boolean isChecked()
    {
        return isChecked;
    }
    @Override
    public void toggle()
    {
        setChecked(!isChecked);
    }

}

attrs.xml

<declare-styleable name="TagFlowLayout">
    <attr name="max_select" format="integer"></attr>
    <attr name="tag_gravity">
        <enum name="left" value="-1" />
        <enum name="center" value="0" />
        <enum name="right" value="1" />
    </attr>
</declare-styleable>

应用层

public class FActivity extends Activity {
    private String[] mVals = new String[]
            {"Hello", "Android", "Weclome Hi ", "Button", "TextView", "Hello",
                    "Android", "Weclome", "Button ImageView", "TextView", "Helloworld",
                    "Android", "Weclome Hello", "Button Text", "TextView","Hello", "Android", "Weclome Hi ", "Button", "TextView", "Hello",
                    "Android", "Weclome", "Button ImageView"};

    private TagFlowLayout mFlowLayout;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.flayout);

        mFlowLayout = (TagFlowLayout) findViewById(R.id.tagflow);
        mFlowLayout.setMaxSelectCount(2);
        mFlowLayout.setAdapter(new TagAdapter<String>(mVals)
        {

            @Override
            public View getView(FlowLayout parent, int position, String s)
            {
                TextView tv = (TextView) LayoutInflater.from(FActivity.this).inflate(R.layout.tv,null);
//                TextView tx=tv.findViewById(R.id.text);
                tv.setText(s);
                return tv;
            }
        });
//        mFlowLayout.setOnSelectListener(new TagFlowLayout.OnSelectListener() {
//            @Override
//            public void onSelected(Set<Integer> selectPosSet) {
////                if()
//            }
//        });
//        mFlowLayout.setOnTagClickListener(new TagFlowLayout.OnTagClickListener() {
//            @Override
//            public boolean onTagClick(View view, int position, FlowLayout parent) {
//
//                return false;
//            }
//        });
    }
}
```
```