Java tutorial
/* * The MIT License (MIT) * Copyright (c) 2016 baoyongzhang <baoyz94@gmail.com> */ package com.baoyz.bigbang; import android.animation.Animator; import android.animation.AnimatorListenerAdapter; import android.content.Context; import android.content.res.TypedArray; import android.graphics.Canvas; import android.graphics.Rect; import android.os.Build; import android.support.annotation.RequiresApi; import android.support.v4.content.ContextCompat; import android.support.v4.view.MotionEventCompat; import android.support.v4.view.NestedScrollingChild; import android.util.AttributeSet; import android.view.Gravity; import android.view.MotionEvent; import android.view.View; import android.view.ViewConfiguration; import android.view.ViewGroup; import android.widget.TextView; import java.util.ArrayList; import java.util.List; /** * Created by baoyongzhang on 2016/10/19. */ public class BigBangLayout extends ViewGroup implements BigBangActionBar.ActionListener, NestedScrollingChild { private int mLineSpace; private int mItemSpace; private Item mTargetItem; private List<Line> mLines; private int mActionBarTopHeight; private int mActionBarBottomHeight; private BigBangActionBar mActionBar; private AnimatorListenerAdapter mActionBarAnimationListener = new AnimatorListenerAdapter() { @Override public void onAnimationEnd(Animator animation) { super.onAnimationEnd(animation); mActionBar.setVisibility(View.GONE); } }; private ActionListener mActionListener; private int mScaledTouchSlop; private float mDownX; private boolean mDisallowedParentIntercept; public BigBangLayout(Context context) { super(context); } public BigBangLayout(Context context, AttributeSet attrs) { this(context, attrs, 0); } public BigBangLayout(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); readAttribute(attrs); } @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP) public BigBangLayout(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) { super(context, attrs, defStyleAttr, defStyleRes); readAttribute(attrs); } private void readAttribute(AttributeSet attrs) { if (attrs != null) { TypedArray typedArray = getContext().obtainStyledAttributes(attrs, R.styleable.BigBangLayout); mItemSpace = typedArray.getDimensionPixelSize(R.styleable.BigBangLayout_itemSpace, getResources().getDimensionPixelSize(R.dimen.big_bang_default_item_space)); mLineSpace = typedArray.getDimensionPixelSize(R.styleable.BigBangLayout_lineSpace, getResources().getDimensionPixelSize(R.dimen.big_bang_default_line_space)); typedArray.recycle(); mActionBarBottomHeight = mLineSpace; mActionBarTopHeight = getResources().getDimensionPixelSize(R.dimen.big_bang_action_bar_height); } // TODO mActionBar = new BigBangActionBar(getContext()); mActionBar.setVisibility(View.GONE); mActionBar.setActionListener(this); addView(mActionBar, 0); setClipChildren(false); mScaledTouchSlop = ViewConfiguration.get(getContext()).getScaledTouchSlop(); } public void addTextItem(String text) { TextView view = new TextView(getContext()); view.setText(text); view.setBackgroundResource(R.drawable.item_background); view.setTextColor(ContextCompat.getColorStateList(getContext(), R.color.bigbang_item_text)); view.setGravity(Gravity.CENTER); addView(view); } public void reset() { for (int i = getChildCount() - 1; i >= 0; i--) { View child = getChildAt(i); if (mActionBar == child) { mActionBar.setVisibility(View.GONE); continue; } removeView(child); } } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { int widthSize = MeasureSpec.getSize(widthMeasureSpec) - getPaddingLeft() - getPaddingRight(); int contentWidthSize = widthSize - mActionBar.getContentPadding(); int heightSize = 0; int childCount = getChildCount(); int measureSpec = MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED); mLines = new ArrayList<>(); Line currentLine = null; int currentLineWidth = contentWidthSize; for (int i = 0; i < childCount; i++) { View child = getChildAt(i); if (mActionBar == child) { continue; } child.measure(measureSpec, measureSpec); if (currentLineWidth > 0) { currentLineWidth += mItemSpace; } currentLineWidth += child.getMeasuredWidth(); if (mLines.size() == 0 || currentLineWidth > contentWidthSize) { heightSize += child.getMeasuredHeight(); currentLineWidth = child.getMeasuredWidth(); currentLine = new Line(mLines.size()); mLines.add(currentLine); } Item item = new Item(currentLine); item.view = child; item.index = i; item.width = child.getMeasuredWidth(); item.height = child.getMeasuredHeight(); currentLine.addItem(item); } Line firstSelectedLine = findFirstSelectedLine(); Line lastSelectedLine = findLastSelectedLine(); if (firstSelectedLine != null && lastSelectedLine != null) { int selectedLineHeight = (lastSelectedLine.index - firstSelectedLine.index + 1) * (firstSelectedLine.getHeight() + mLineSpace); mActionBar.measure(MeasureSpec.makeMeasureSpec(widthSize, MeasureSpec.EXACTLY), MeasureSpec.makeMeasureSpec(selectedLineHeight, MeasureSpec.UNSPECIFIED)); } int size = heightSize + getPaddingTop() + getPaddingBottom() + (mLines.size() - 1) * mLineSpace + mActionBarTopHeight + mActionBarBottomHeight; super.onMeasure(widthMeasureSpec, MeasureSpec.makeMeasureSpec(size, MeasureSpec.EXACTLY)); } @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { int top; int left; int offsetTop; Line lastSelectedLine = findLastSelectedLine(); Line firstSelectedLine = findFirstSelectedLine(); for (int i = 0; i < mLines.size(); i++) { Line line = mLines.get(i); List<Item> items = line.getItems(); left = getPaddingLeft() + mActionBar.getContentPadding(); if (firstSelectedLine != null && firstSelectedLine.index > line.index) { offsetTop = -mActionBarTopHeight; } else if (lastSelectedLine != null && lastSelectedLine.index < line.index) { offsetTop = mActionBarBottomHeight; } else { offsetTop = 0; } for (int j = 0; j < items.size(); j++) { Item item = items.get(j); top = getPaddingTop() + i * (item.height + mLineSpace) + offsetTop + mActionBarTopHeight; View child = item.view; int oldTop = child.getTop(); child.layout(left, top, left + child.getMeasuredWidth(), top + child.getMeasuredHeight()); if (oldTop != top) { int translationY = oldTop - top; child.setTranslationY(translationY); child.animate().translationYBy(-translationY).setDuration(200).start(); } left += child.getMeasuredWidth() + mItemSpace; } } if (firstSelectedLine != null && lastSelectedLine != null) { mActionBar.setVisibility(View.VISIBLE); mActionBar.setAlpha(1); int oldTop = mActionBar.getTop(); int actionBarTop = firstSelectedLine.index * (firstSelectedLine.getHeight() + mLineSpace) + getPaddingTop(); mActionBar.layout(getPaddingLeft(), actionBarTop, getPaddingLeft() + mActionBar.getMeasuredWidth(), actionBarTop + mActionBar.getMeasuredHeight()); if (oldTop != actionBarTop) { int translationY = oldTop - actionBarTop; mActionBar.setTranslationY(translationY); mActionBar.animate().translationYBy(-translationY).setDuration(200).start(); } } else { if (mActionBar.getVisibility() == View.VISIBLE) { mActionBar.animate().alpha(0).setDuration(200).setListener(mActionBarAnimationListener).start(); } } } private Line findLastSelectedLine() { Line result = null; for (Line line : mLines) { if (line.hasSelected()) { result = line; } } return result; } private Line findFirstSelectedLine() { for (Line line : mLines) { if (line.hasSelected()) { return line; } } return null; } @Override protected void onDraw(Canvas canvas) { super.onDraw(canvas); } // @Override // public boolean onInterceptTouchEvent(MotionEvent ev) { // return true; // } @Override public boolean onTouchEvent(MotionEvent event) { int actionMasked = MotionEventCompat.getActionMasked(event); switch (actionMasked) { case MotionEvent.ACTION_DOWN: mDownX = event.getX(); mDisallowedParentIntercept = false; case MotionEvent.ACTION_MOVE: int x = (int) event.getX(); if (!mDisallowedParentIntercept && Math.abs(x - mDownX) > mScaledTouchSlop) { getParent().requestDisallowInterceptTouchEvent(true); mDisallowedParentIntercept = true; } Item item = findItemByPoint(x, (int) event.getY()); if (mTargetItem != item) { mTargetItem = item; if (item != null) { item.setSelected(!item.isSelected()); ItemState state = new ItemState(); state.item = item; state.isSelected = item.isSelected(); if (mItemState == null) { mItemState = state; } else { state.next = mItemState; mItemState = state; } } } break; case MotionEvent.ACTION_CANCEL: if (mItemState != null) { ItemState state = mItemState; while (state != null) { state.item.setSelected(!state.isSelected); state = state.next; } } case MotionEvent.ACTION_UP: requestLayout(); invalidate(); mTargetItem = null; if (mDisallowedParentIntercept) { getParent().requestDisallowInterceptTouchEvent(false); } mItemState = null; break; } return true; } ItemState mItemState; class ItemState { Item item; boolean isSelected; ItemState next; } private Item findItemByPoint(int x, int y) { for (Line line : mLines) { List<Item> items = line.getItems(); for (Item item : items) { if (item.getRect().contains(x, y)) { return item; } } } return null; } private View findChildByPoint(int x, int y) { int childCount = getChildCount(); for (int i = 0; i < childCount; i++) { View child = getChildAt(i); Rect rect = new Rect(); child.getHitRect(rect); if (rect.contains(x, y)) { return child; } } return null; } private String makeSelectedText() { StringBuilder builder = new StringBuilder(); for (Line line : mLines) { builder.append(line.getSelectedText()); } return builder.toString(); } @Override public void onSearch() { if (mActionListener != null) { String text = makeSelectedText(); mActionListener.onSearch(text); } } @Override public void onShare() { if (mActionListener != null) { String text = makeSelectedText(); mActionListener.onShare(text); } } @Override public void onCopy() { if (mActionListener != null) { String text = makeSelectedText(); mActionListener.onCopy(text); } } public void setActionListener(ActionListener actionListener) { mActionListener = actionListener; } static class Line { int index; List<Item> items; public Line(int index) { this.index = index; } void addItem(Item item) { if (items == null) { items = new ArrayList<>(); } items.add(item); } List<Item> getItems() { return items; } boolean hasSelected() { for (Item item : items) { if (item.isSelected()) { return true; } } return false; } int getHeight() { List<Item> items = getItems(); if (items != null && items.size() > 0) { return items.get(0).view.getMeasuredHeight(); } return 0; } String getSelectedText() { StringBuilder builder = new StringBuilder(); List<Item> items = getItems(); if (items != null && items.size() > 0) { for (Item item : items) { if (item.isSelected()) { builder.append(item.getText()); } } } return builder.toString(); } } static class Item { Line line; int index; int height; int width; View view; public Item(Line line) { this.line = line; } Rect getRect() { Rect rect = new Rect(); view.getHitRect(rect); return rect; } boolean isSelected() { return view.isSelected(); } void setSelected(boolean selected) { view.setSelected(selected); } CharSequence getText() { return ((TextView) view).getText(); } } /** * Action Listener */ public interface ActionListener { void onSearch(String text); void onShare(String text); void onCopy(String text); } }