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/* * Copyright 2015 Hippo Seven * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.hippo.widget.slidingdrawerlayout; import android.app.Activity; import android.content.Context; import android.content.res.Configuration; import android.graphics.drawable.Drawable; import android.support.annotation.StringRes; import android.support.v4.widget.DrawerLayout; import android.support.v7.app.AppCompatActivity; import android.support.v7.graphics.drawable.DrawerArrowDrawable; import android.support.v7.widget.Toolbar; import android.util.Log; import android.view.Gravity; import android.view.MenuItem; import android.view.View; /** * This class provides a handy way to tie together the functionality of * {@link DrawerLayout} and the framework <code>ActionBar</code> to * implement the recommended design for navigation drawers. * * <p>To use <code>ActionBarDrawerToggle</code>, create one in your Activity and call through * to the following methods corresponding to your Activity callbacks:</p> * * <ul> * <li>{@link Activity#onConfigurationChanged(Configuration) * onConfigurationChanged} * <li>{@link Activity#onOptionsItemSelected(MenuItem) * onOptionsItemSelected}</li> * </ul> * * <p>Call {@link #syncState()} from your <code>Activity</code>'s * {@link Activity#onPostCreate(android.os.Bundle) onPostCreate} to synchronize the * indicator with the state of the linked DrawerLayout after <code>onRestoreInstanceState</code> * has occurred.</p> * * <p><code>ActionBarDrawerToggle</code> can be used directly as a * {@link DrawerLayout.DrawerListener}, or if you are already providing * your own listener, call through to each of the listener methods from your own.</p> * * <p> * You can customize the the animated toggle by defining the * {@link android.support.v7.appcompat.R.styleable#DrawerArrowToggle drawerArrowStyle} in your * ActionBar theme. */ public class ActionBarDrawerToggle implements SlidingDrawerLayout.DrawerListener { private android.support.v7.app.ActionBarDrawerToggle.Delegate mActivityImpl; private final SlidingDrawerLayout mDrawerLayout; private DrawerToggle mSlider; private Drawable mHomeAsUpIndicator; private boolean mDrawerIndicatorEnabled = true; private boolean mHasCustomUpIndicator; private final int mOpenDrawerContentDescRes; private final int mCloseDrawerContentDescRes; // used in toolbar mode when DrawerToggle is disabled private View.OnClickListener mToolbarNavigationClickListener; // If developer does not set displayHomeAsUp, DrawerToggle won't show up. // DrawerToggle logs a warning if this case is detected private boolean mWarnedForDisplayHomeAsUp = false; /** * Construct a new ActionBarDrawerToggle. * * <p>The given {@link Activity} will be linked to the specified {@link DrawerLayout} and * its Actionbar's Up button will be set to a custom drawable. * <p>This drawable shows a Hamburger icon when drawer is closed and an arrow when drawer * is open. It animates between these two states as the drawer opens.</p> * * <p>String resources must be provided to describe the open/close drawer actions for * accessibility services.</p> * * @param activity The Activity hosting the drawer. Should have an ActionBar. * @param drawerLayout The DrawerLayout to link to the given Activity's ActionBar * @param openDrawerContentDescRes A String resource to describe the "open drawer" action * for accessibility * @param closeDrawerContentDescRes A String resource to describe the "close drawer" action * for accessibility */ public ActionBarDrawerToggle(Activity activity, SlidingDrawerLayout drawerLayout, @StringRes int openDrawerContentDescRes, @StringRes int closeDrawerContentDescRes) { this(activity, null, drawerLayout, null, openDrawerContentDescRes, closeDrawerContentDescRes); } /** * Construct a new ActionBarDrawerToggle with a Toolbar. * <p> * The given {@link Activity} will be linked to the specified {@link DrawerLayout} and * the Toolbar's navigation icon will be set to a custom drawable. Using this constructor * will set Toolbar's navigation click listener to toggle the drawer when it is clicked. * <p> * This drawable shows a Hamburger icon when drawer is closed and an arrow when drawer * is open. It animates between these two states as the drawer opens. * <p> * String resources must be provided to describe the open/close drawer actions for * accessibility services. * <p> * Please use {@link #ActionBarDrawerToggle(Activity, SlidingDrawerLayout, int, int)} if you are * setting the Toolbar as the ActionBar of your activity. * * @param activity The Activity hosting the drawer. * @param toolbar The toolbar to use if you have an independent Toolbar. * @param drawerLayout The DrawerLayout to link to the given Activity's ActionBar * @param openDrawerContentDescRes A String resource to describe the "open drawer" action * for accessibility * @param closeDrawerContentDescRes A String resource to describe the "close drawer" action * for accessibility */ public ActionBarDrawerToggle(Activity activity, SlidingDrawerLayout drawerLayout, Toolbar toolbar, @StringRes int openDrawerContentDescRes, @StringRes int closeDrawerContentDescRes) { this(activity, toolbar, drawerLayout, null, openDrawerContentDescRes, closeDrawerContentDescRes); } /** * In the future, we can make this constructor public if we want to let developers customize * the * animation. */ <T extends Drawable & DrawerToggle> ActionBarDrawerToggle(Activity activity, Toolbar toolbar, SlidingDrawerLayout drawerLayout, T slider, @StringRes int openDrawerContentDescRes, @StringRes int closeDrawerContentDescRes) { if (activity instanceof AppCompatActivity) { // Allow the Activity to provide an impl mActivityImpl = ((AppCompatActivity) activity).getDrawerToggleDelegate(); } if (mActivityImpl == null) { throw new IllegalStateException(); } mDrawerLayout = drawerLayout; mOpenDrawerContentDescRes = openDrawerContentDescRes; mCloseDrawerContentDescRes = closeDrawerContentDescRes; if (slider == null) { mSlider = new DrawerArrowDrawableToggle(activity, mActivityImpl.getActionBarThemedContext()); } else { mSlider = slider; } mHomeAsUpIndicator = getThemeUpIndicator(); } /** * Synchronize the state of the drawer indicator/affordance with the linked DrawerLayout. * * <p>This should be called from your <code>Activity</code>'s * {@link Activity#onPostCreate(android.os.Bundle) onPostCreate} method to synchronize after * the DrawerLayout's instance state has been restored, and any other time when the state * may have diverged in such a way that the ActionBarDrawerToggle was not notified. * (For example, if you stop forwarding appropriate drawer events for a period of time.)</p> */ public void syncState() { if (mDrawerLayout.isDrawerOpen(Gravity.LEFT)) { mSlider.setPosition(1); } else { mSlider.setPosition(0); } if (mDrawerIndicatorEnabled) { setActionBarUpIndicator((Drawable) mSlider, mDrawerLayout.isDrawerOpen(Gravity.LEFT) ? mCloseDrawerContentDescRes : mOpenDrawerContentDescRes); } } /** * This method should always be called by your <code>Activity</code>'s * {@link Activity#onConfigurationChanged(Configuration) * onConfigurationChanged} * method. * * @param newConfig The new configuration */ public void onConfigurationChanged(Configuration newConfig) { // Reload drawables that can change with configuration if (!mHasCustomUpIndicator) { mHomeAsUpIndicator = getThemeUpIndicator(); } syncState(); } /** * This method should be called by your <code>Activity</code>'s * {@link Activity#onOptionsItemSelected(MenuItem) onOptionsItemSelected} method. * If it returns true, your <code>onOptionsItemSelected</code> method should return true and * skip further processing. * * @param item the MenuItem instance representing the selected menu item * @return true if the event was handled and further processing should not occur */ public boolean onOptionsItemSelected(MenuItem item) { if (item != null && item.getItemId() == android.R.id.home && mDrawerIndicatorEnabled) { toggle(); return true; } return false; } private void toggle() { if (mDrawerLayout.isDrawerOpen(Gravity.LEFT)) { mDrawerLayout.closeDrawer(Gravity.LEFT); } else { mDrawerLayout.openDrawer(Gravity.LEFT); } } /** * Set the up indicator to display when the drawer indicator is not * enabled. * <p> * If you pass <code>null</code> to this method, the default drawable from * the theme will be used. * * @param indicator A drawable to use for the up indicator, or null to use * the theme's default * @see #setDrawerIndicatorEnabled(boolean) */ public void setHomeAsUpIndicator(Drawable indicator) { if (indicator == null) { mHomeAsUpIndicator = getThemeUpIndicator(); mHasCustomUpIndicator = false; } else { mHomeAsUpIndicator = indicator; mHasCustomUpIndicator = true; } if (!mDrawerIndicatorEnabled) { setActionBarUpIndicator(mHomeAsUpIndicator, 0); } } /** * Set the up indicator to display when the drawer indicator is not * enabled. * <p> * If you pass 0 to this method, the default drawable from the theme will * be used. * * @param resId Resource ID of a drawable to use for the up indicator, or 0 * to use the theme's default * @see #setDrawerIndicatorEnabled(boolean) */ public void setHomeAsUpIndicator(int resId) { Drawable indicator = null; if (resId != 0) { indicator = mDrawerLayout.getResources().getDrawable(resId); } setHomeAsUpIndicator(indicator); } /** * @return true if the enhanced drawer indicator is enabled, false otherwise * @see #setDrawerIndicatorEnabled(boolean) */ public boolean isDrawerIndicatorEnabled() { return mDrawerIndicatorEnabled; } /** * Enable or disable the drawer indicator. The indicator defaults to enabled. * * <p>When the indicator is disabled, the <code>ActionBar</code> will revert to displaying * the home-as-up indicator provided by the <code>Activity</code>'s theme in the * <code>android.R.attr.homeAsUpIndicator</code> attribute instead of the animated * drawer glyph.</p> * * @param enable true to enable, false to disable */ public void setDrawerIndicatorEnabled(boolean enable) { if (enable != mDrawerIndicatorEnabled) { if (enable) { setActionBarUpIndicator((Drawable) mSlider, mDrawerLayout.isDrawerOpen(Gravity.LEFT) ? mCloseDrawerContentDescRes : mOpenDrawerContentDescRes); } else { setActionBarUpIndicator(mHomeAsUpIndicator, 0); } mDrawerIndicatorEnabled = enable; } } /** * {@link DrawerLayout.DrawerListener} callback method. If you do not use your * ActionBarDrawerToggle instance directly as your DrawerLayout's listener, you should call * through to this method from your own listener object. * * @param drawerView The child view that was moved * @param slideOffset The new offset of this drawer within its range, from 0-1 */ @Override public void onDrawerSlide(View drawerView, float slideOffset) { mSlider.setPosition(Math.min(1f, Math.max(0, slideOffset))); } /** * {@link DrawerLayout.DrawerListener} callback method. If you do not use your * ActionBarDrawerToggle instance directly as your DrawerLayout's listener, you should call * through to this method from your own listener object. * * @param drawerView Drawer view that is now open */ @Override public void onDrawerOpened(View drawerView) { mSlider.setPosition(1); if (mDrawerIndicatorEnabled) { setActionBarDescription(mCloseDrawerContentDescRes); } } /** * {@link DrawerLayout.DrawerListener} callback method. If you do not use your * ActionBarDrawerToggle instance directly as your DrawerLayout's listener, you should call * through to this method from your own listener object. * * @param drawerView Drawer view that is now closed */ @Override public void onDrawerClosed(View drawerView) { mSlider.setPosition(0); if (mDrawerIndicatorEnabled) { setActionBarDescription(mOpenDrawerContentDescRes); } } @Override public void onDrawerStateChanged(View drawerView, int newState) { } /** * Returns the fallback listener for Navigation icon click events. * * @return The click listener which receives Navigation click events from Toolbar when * drawer indicator is disabled. * @see #setToolbarNavigationClickListener(View.OnClickListener) * @see #setDrawerIndicatorEnabled(boolean) * @see #isDrawerIndicatorEnabled() */ public View.OnClickListener getToolbarNavigationClickListener() { return mToolbarNavigationClickListener; } /** * When DrawerToggle is constructed with a Toolbar, it sets the click listener on * the Navigation icon. If you want to listen for clicks on the Navigation icon when * DrawerToggle is disabled ({@link #setDrawerIndicatorEnabled(boolean)}, you should call this * method with your listener and DrawerToggle will forward click events to that listener * when drawer indicator is disabled. * * @see #setDrawerIndicatorEnabled(boolean) */ public void setToolbarNavigationClickListener(View.OnClickListener onToolbarNavigationClickListener) { mToolbarNavigationClickListener = onToolbarNavigationClickListener; } void setActionBarUpIndicator(Drawable upDrawable, int contentDescRes) { if (!mWarnedForDisplayHomeAsUp && !mActivityImpl.isNavigationVisible()) { Log.w("ActionBarDrawerToggle", "DrawerToggle may not show up because NavigationIcon" + " is not visible. You may need to call " + "actionbar.setDisplayHomeAsUpEnabled(true);"); mWarnedForDisplayHomeAsUp = true; } mActivityImpl.setActionBarUpIndicator(upDrawable, contentDescRes); } void setActionBarDescription(int contentDescRes) { mActivityImpl.setActionBarDescription(contentDescRes); } Drawable getThemeUpIndicator() { return mActivityImpl.getThemeUpIndicator(); } static class DrawerArrowDrawableToggle extends DrawerArrowDrawable implements DrawerToggle { private final Activity mActivity; public DrawerArrowDrawableToggle(Activity activity, Context themedContext) { super(themedContext); mActivity = activity; } @Override public void setPosition(float position) { if (position == 1f) { setVerticalMirror(true); } else if (position == 0f) { setVerticalMirror(false); } setProgress(position); } @Override public float getPosition() { return getProgress(); } } /** * Interface for toggle drawables. Can be public in the future */ interface DrawerToggle { void setPosition(float position); float getPosition(); } }