Java tutorial
/* * The MIT License (MIT) * * Copyright (c) 2014 Francesco Florio * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. * * Francesco Florio * Email: floriofrancesco@gmail.com * Twitter: @fr4style * Linkedin: it.linkedin.com/pub/francesco-florio/21/62/a68/ * * Made with love in the south of Italy (Cosenza, Italy) * * This class is based on Flavien Laurent article: http://flavienlaurent.com/blog/2013/08/28/each-navigation-drawer-hides-a-viewdraghelper */ package com.fflorio.library.hookedslidingmenu.ui; import android.content.Context; import android.support.v4.view.MotionEventCompat; import android.support.v4.view.ViewCompat; import android.support.v4.widget.ViewDragHelper; import android.util.AttributeSet; import android.view.MotionEvent; import android.view.View; import android.view.ViewGroup; import com.fflorio.library.hookedslidingmenu.R; import java.util.ArrayList; import java.util.List; public class HookedMenuLayout extends ViewGroup { //Obj private ViewDragHelper mDragHelper; private List<HookedMenuEventListener> listeners = new ArrayList<HookedMenuEventListener>(); //UI private View hookView; //the view to drag private View menuContent; //Values /** menu status */ private boolean isOpen = false; private boolean startClosed = true; private float mInitialMotionX; private float mInitialMotionY; private int displayW; private int mLeft = Integer.MIN_VALUE; private int mDragRange; /** Value: 0 if the menu is closed, 1 otherwise */ private float mDragOffset; //----------------------------------------------------------- // Constructors && Init //----------------------------------------------------------- public HookedMenuLayout(Context context) { super(context); init(); } public HookedMenuLayout(Context context, AttributeSet attrs) { super(context, attrs); init(); } public HookedMenuLayout(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); init(); } private void init() { mDragHelper = ViewDragHelper.create(this, 1.0f, callback); displayW = getResources().getDisplayMetrics().widthPixels; } @Override protected void onFinishInflate() { hookView = findViewById(R.id.hook); menuContent = findViewById(R.id.menuContent); } //----------------------------------------------------------- // EventListener //----------------------------------------------------------- public void addHookedMenuEventListener(HookedMenuEventListener listener) { listeners.add(listener); } public void removeHookedMenuEventListener(HookedMenuEventListener listener) { listeners.remove(listener); } public void updateListeners(boolean newStatus) { if (isOpen == newStatus) return; for (HookedMenuEventListener listener : listeners) listener.onStatusChanged(newStatus); } public boolean isOpen() { return isOpen; } //----------------------------------------------------------- // CustomLayout implementation //----------------------------------------------------------- @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { measureChildren(widthMeasureSpec, heightMeasureSpec); int maxWidth = MeasureSpec.getSize(widthMeasureSpec); int maxHeight = MeasureSpec.getSize(heightMeasureSpec); setMeasuredDimension(resolveSizeAndState(maxWidth, widthMeasureSpec, 0), resolveSizeAndState(maxHeight, heightMeasureSpec, 0)); } @Override protected void onLayout(boolean changed, int l, int t, int r, int b) { final int hookMeasuredWidth = hookView.getMeasuredWidth(); final int menuMeasuredWidth = menuContent.getMeasuredWidth(); if (mLeft == Integer.MIN_VALUE) mLeft = (startClosed) ? displayW - hookMeasuredWidth : displayW - hookMeasuredWidth - menuMeasuredWidth; mDragRange = menuMeasuredWidth; hookView.layout(mLeft, 0, mLeft + hookMeasuredWidth, b); menuContent.layout(mLeft + hookMeasuredWidth, 0, mLeft + hookMeasuredWidth + menuMeasuredWidth, b); } //----------------------------------------------------------- // Manage touchEvents //----------------------------------------------------------- @Override public void computeScroll() { if (mDragHelper.continueSettling(true)) ViewCompat.postInvalidateOnAnimation(this); } @Override public boolean onInterceptTouchEvent(MotionEvent ev) { final int action = MotionEventCompat.getActionMasked(ev); if (action != MotionEvent.ACTION_DOWN) { //???? mDragHelper.cancel(); return super.onInterceptTouchEvent(ev); } if (action == MotionEvent.ACTION_CANCEL || action == MotionEvent.ACTION_UP) { mDragHelper.cancel(); return false; } final float x = ev.getX(); final float y = ev.getY(); boolean interceptTap = false; switch (action) { case MotionEvent.ACTION_DOWN: { mInitialMotionX = x; mInitialMotionY = y; interceptTap = mDragHelper.isViewUnder(hookView, (int) x, (int) y); } break; case MotionEvent.ACTION_MOVE: { final float adx = Math.abs(x - mInitialMotionX); final float ady = Math.abs(y - mInitialMotionY); final int slop = mDragHelper.getTouchSlop(); if (adx > slop && ady > adx) { mDragHelper.cancel(); return false; } } } return mDragHelper.shouldInterceptTouchEvent(ev) || interceptTap; } @Override public boolean onTouchEvent(MotionEvent event) { mDragHelper.processTouchEvent(event); final int action = event.getAction(); final float x = event.getX(); final float y = event.getY(); boolean isHeaderViewUnder = mDragHelper.isViewUnder(hookView, (int) x, (int) y); switch (action & MotionEventCompat.ACTION_MASK) { case MotionEvent.ACTION_DOWN: { mInitialMotionX = x; mInitialMotionY = y; } break; case MotionEvent.ACTION_UP: { final float dx = x - mInitialMotionX; final float dy = y - mInitialMotionY; final int slop = mDragHelper.getTouchSlop(); if ((dx * dx + dy * dy) < (slop * slop) && isHeaderViewUnder) { if (mDragOffset == 0) smoothSlideTo(1f); else smoothSlideTo(0f); } } break; } return isHeaderViewUnder && isViewHit(hookView, (int) x, (int) y) || isViewHit(menuContent, (int) x, (int) y); } private boolean isViewHit(View view, int x, int y) { int[] viewLocation = new int[2]; view.getLocationOnScreen(viewLocation); int[] parentLocation = new int[2]; this.getLocationOnScreen(parentLocation); int screenX = parentLocation[0] + x; int screenY = parentLocation[1] + y; return screenX >= viewLocation[0] && screenX < viewLocation[0] + view.getWidth() && screenY >= viewLocation[1] && screenY < viewLocation[1] + view.getHeight(); } public void open() { smoothSlideTo(1.0f); } public void close() { smoothSlideTo(0.0f); } /** * * @param slideOffset - the percentage of movement * @return */ protected boolean smoothSlideTo(float slideOffset) { final int leftBound = displayW - hookView.getWidth(); int x = (int) (leftBound - slideOffset * mDragRange); if (mDragHelper.smoothSlideViewTo(hookView, x, hookView.getTop())) { ViewCompat.postInvalidateOnAnimation(this); return true; } return false; } //----------------------------------------------------------- // Callbacks //----------------------------------------------------------- /** * Object that configure VDH behaviors */ private ViewDragHelper.Callback callback = new ViewDragHelper.Callback() { @Override public boolean tryCaptureView(View child, int pointerId) { return child == hookView; } @Override public int getViewHorizontalDragRange(View child) { return mDragRange; } //Enable the horizontal scrolling @Override public int clampViewPositionHorizontal(View child, int left, int dx) { final int rightBound = getWidth() - hookView.getWidth(); final int leftBound = rightBound - menuContent.getWidth(); final int newLeft = Math.min(Math.max(left, leftBound), rightBound); return newLeft; } @Override public void onViewPositionChanged(View changedView, int left, int top, int dx, int dy) { mLeft = left; //0 if the menu is closed, 1 otherwise mDragOffset = (float) Math.abs(left + hookView.getWidth() - displayW) / mDragRange; //menuContent.setAlpha(mDragOffset); Add an alpha behaviour to the contentview requestLayout(); if (mDragOffset == 0) { boolean newStatus = false; updateListeners(newStatus); isOpen = newStatus; } else if (mDragOffset == 1) { boolean newStatus = true; updateListeners(newStatus); isOpen = newStatus; } } @Override public void onViewReleased(View releasedChild, float xvel, float yvel) { boolean toOpen; if (xvel < 0) toOpen = true; else if (xvel > 0) toOpen = false; else toOpen = mDragOffset > 0.5f; int left = (toOpen) ? displayW - hookView.getWidth() - mDragRange : displayW - hookView.getWidth(); mDragHelper.settleCapturedViewAt(left, releasedChild.getTop()); invalidate(); } }; }