Java tutorial
/* * Copyright (C) 2015 The Android Open Source Project * * 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 android.support.v7.app; import android.content.res.Configuration; import android.content.res.Resources; import android.content.res.TypedArray; import android.os.Bundle; import android.support.v4.view.GravityCompat; import android.support.v4.widget.DrawerLayout; import android.support.v7.appcompat.test.R; import android.support.v7.testutils.BaseTestActivity; import android.support.v7.testutils.Shakespeare; import android.support.v7.widget.Toolbar; import android.view.MenuItem; import android.view.View; import android.view.ViewTreeObserver; import android.widget.AdapterView; import android.widget.ArrayAdapter; import android.widget.ListView; import android.widget.TextView; /** * Test activity for testing various APIs and interactions for DrawerLayout. It follows * a common usage of the DrawerLayout widget combined with Toolbar in the Android support library * that respect the * <a href="https://www.google.com/design/spec/patterns/navigation-drawer.html">Material design * guidelines</a> for the drawer component. */ public class DrawerLayoutActivity extends BaseTestActivity { private DrawerLayout mDrawerLayout; private ListView mDrawer; private TextView mContent; private ActionBarDrawerToggle mDrawerToggle; private Toolbar mToolbar; @Override protected int getContentViewLayoutResId() { return R.layout.drawer_layout; } @Override protected void onContentViewSet() { super.onContentViewSet(); mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout); mDrawer = (ListView) findViewById(R.id.start_drawer); mContent = (TextView) findViewById(R.id.content_text); mDrawerLayout.setDrawerShadow(R.drawable.drawer_shadow, GravityCompat.START); // The drawer title must be set in order to announce state changes when // accessibility is turned on. This is typically a simple description, // e.g. "Navigation". mDrawerLayout.setDrawerTitle(GravityCompat.START, getString(R.string.drawer_title)); mDrawer.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, Shakespeare.TITLES)); mDrawer.setOnItemClickListener(new DrawerItemClickListener()); // Find the toolbar in our layout and set it as the support action bar on the activity. // This is required to have the drawer slide "over" the toolbar. mToolbar = (Toolbar) findViewById(R.id.toolbar); mToolbar.setTitle(R.string.drawer_title); setSupportActionBar(mToolbar); getSupportActionBar().setDisplayHomeAsUpEnabled(true); getSupportActionBar().setDisplayShowHomeEnabled(false); // ActionBarDrawerToggle provides convenient helpers for tying together the // prescribed interactions between a top-level sliding drawer and the action bar. // Note that, as the Javadocs of ActionBarDrawerToggle constructors say, we are // *not* using a constructor that gets a Toolbar since we're setting our toolbar // dynamically at runtime. Furthermore, as the drawer is sliding over the toolbar, // we are suppressing the morphing animation from hamburger to back arrow by // calling super.onDrawerSlide with slideOffset=0.0f. In case your app only has // top-level pages and doesn't need back arrow visuals at all, you can set up // your activity theme to have attribute named "drawerArrowStyle" that points // to an extension of Widget.AppCompat.DrawerArrowToggle that has its "spinBars" // attribute set to false. mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout, R.string.drawer_open, R.string.drawer_close) { @Override public void onDrawerOpened(View drawerView) { super.onDrawerOpened(drawerView); super.onDrawerSlide(drawerView, 0.0f); } @Override public void onDrawerSlide(View drawerView, float slideOffset) { super.onDrawerSlide(drawerView, 0.0f); } }; mDrawerLayout.addDrawerListener(mDrawerToggle); // Configure the background color fill of the system status bar (on supported platform // versions) and the toolbar itself. We're using the same color, and android:statusBar // from the theme makes the status bar slightly darker. final int metalBlueColor = getResources().getColor(R.color.drawer_sample_metal_blue); mDrawerLayout.setStatusBarBackgroundColor(metalBlueColor); mToolbar.setBackgroundColor(metalBlueColor); // Register a pre-draw listener to get the initial width of the DrawerLayout so // that we can determine the width of the drawer based on the Material spec at // https://www.google.com/design/spec/patterns/navigation-drawer.html#navigation-drawer-specs mDrawerLayout.getViewTreeObserver().addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() { @Override public boolean onPreDraw() { // What is the width of the entire DrawerLayout? final int drawerLayoutWidth = mDrawerLayout.getWidth(); // What is the action bar size? final Resources.Theme theme = mDrawerLayout.getContext().getTheme(); final TypedArray a = theme .obtainStyledAttributes(new int[] { android.support.v7.appcompat.R.attr.actionBarSize }); final int actionBarSize = a.getDimensionPixelSize(0, 0); if (a != null) { a.recycle(); } // Compute the width of the drawer and set it on the layout params. final int idealDrawerWidth = 5 * actionBarSize; final int maxDrawerWidth = Math.max(0, drawerLayoutWidth - actionBarSize); final int drawerWidth = Math.min(idealDrawerWidth, maxDrawerWidth); final DrawerLayout.LayoutParams drawerLp = (DrawerLayout.LayoutParams) mDrawer.getLayoutParams(); drawerLp.width = drawerWidth; mDrawer.setLayoutParams(drawerLp); // Remove ourselves as the pre-draw listener since this is a one-time // configuration. mDrawerLayout.getViewTreeObserver().removeOnPreDrawListener(this); return true; } }); } @Override protected void onPostCreate(Bundle savedInstanceState) { super.onPostCreate(savedInstanceState); // Sync the toggle state after onRestoreInstanceState has occurred. mDrawerToggle.syncState(); } @Override public boolean onOptionsItemSelected(MenuItem item) { /* * The action bar home/up action should open or close the drawer. * The drawer toggle will take care of this. */ if (mDrawerToggle.onOptionsItemSelected(item)) { return true; } return super.onOptionsItemSelected(item); } @Override public void onBackPressed() { // Is the drawer open? if (mDrawerLayout.isDrawerOpen(mDrawer)) { // Close the drawer and return. mDrawerLayout.closeDrawer(mDrawer); return; } super.onBackPressed(); } @Override public void onConfigurationChanged(Configuration newConfig) { super.onConfigurationChanged(newConfig); mDrawerToggle.onConfigurationChanged(newConfig); } /** * This list item click listener implements very simple view switching by changing * the primary content text. The drawer is closed when a selection is made. */ private class DrawerItemClickListener implements ListView.OnItemClickListener { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { mContent.setText(Shakespeare.DIALOGUE[position]); mToolbar.setTitle(Shakespeare.TITLES[position]); mDrawerLayout.closeDrawer(mDrawer); } } }