通過上一篇對慕課網導航效果的分析和驗證,今天咱們就來編碼實現這一效果。尚未看過上一篇文章的同窗,建議先看看手把手教你實現慕課網引導頁效果(一)——分析驗證。html
經過本篇文章,咱們能夠學習到:android
在編碼以前,先回顧下慕課網的導航效果。網絡
1.首先,咱們先實現顯示Logo的Activity(簡稱MainActivity),這個比較簡單。看上面的GIF圖,MainActivity顯示一會時間後向左滑動消失,GuideActivity從右邊滑動出來。那就講講其中的Activity轉間動畫(Transition animation)。ide
通常使用下面的方式來實現:post
public void overridePendingTransition (int enterAnim, int exitAnim) //一般咱們通常在startActivity(Intent)或finish()方法中調用此方法 //其中enterAnim表示新Activity的進入動畫,exitAnim表示舊Activity的退出動畫 //從Android4.1後,能夠經過ActivityOptions將轉間動畫做爲Bundle傳入startActivity(Activity,Bundle)來實現
來看代碼實現:學習
public class MainActivity extends AppCompatActivity { private Handler mHandler = new Handler(); private Context mContext; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); mContext = this; //使用handler定時跳轉到GuideActivity mHandler.postDelayed(new Runnable() { @Override public void run() { Intent intent = new Intent(mContext,GuideActivity.class); //設置跳轉動畫 //第一種方式實現 startActivity(new Intent(mContext,GuideActivity.class)); finish(); overridePendingTransition(R.anim.slide_in_right,R.anim.slide_out_left); //第二種方式實現 // ActivityOptionsCompat optionsCompat = // ActivityOptionsCompat.makeCustomAnimation(mContext,R.anim.slide_in_right, // R.anim.slide_out_left); // ActivityCompat.startActivity(MainActivity.this,intent,optionsCompat.toBundle()); // startActivity(new Intent(mContext,GuideActivity.class)); // finish(); } }, 500); } }
運行效果:
動畫
2.接下來,實現滑動導航效果。相信如今講這個的文章很是多,今天就當再複習一遍。呵呵,溫故而知新。
咱們使用ViewPager+Fragment+FragmentPagerAdapter來實現。ui
通常有三個步驟:this
在這裏,咱們只須要建立一種Fragment便可。經過index參數來設置顯示不一樣的圖片和播放不一樣的視頻。編碼
下面是GuideFragment的代碼:
/** * Created by JohnTsai on 16/3/3. */ public class GuideFragment extends Fragment { public static String TAG = GuideFragment.class.getSimpleName(); public static String KEY = "index"; private VideoView mVideoView; private ImageView mImageView; private int index; @Nullable @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View guideView = inflater.inflate(R.layout.fragment_guide,container,false); mVideoView = (VideoView) guideView.findViewById(R.id.videoView); mImageView = (ImageView) guideView.findViewById(R.id.wordView); switch (index){ case 0: mImageView.setImageResource(R.mipmap.guide_1); break; case 1: mImageView.setImageResource(R.mipmap.guide_2); break; case 2: mImageView.setImageResource(R.mipmap.guide_3); break; } Log.d(TAG,"onCreateView"); return guideView; } @Override public void onCreate(@Nullable Bundle savedInstanceState) { super.onCreate(savedInstanceState); Bundle bundle = getArguments(); index = bundle.getInt(KEY); Log.d(TAG,"onCreate"); } public static GuideFragment newInstance(int index) { Bundle args = new Bundle(); args.putInt(KEY, index); GuideFragment fragment = new GuideFragment(); fragment.setArguments(args); return fragment; } }
以及GuideActivity的代碼
/** * Created by JohnTsai on 16/3/3. */ public class GuideActivity extends AppCompatActivity{ private ImageView mDotOne,mDotTwo,mDotThree; private LinearLayout mLayoutBtn; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_guide); //初始化控件 ViewPager mViewPager = (ViewPager) findViewById(R.id.viewPager); mDotOne = (ImageView) findViewById(R.id.guide_dot1); mDotTwo = (ImageView) findViewById(R.id.guide_dot2); mDotThree = (ImageView) findViewById(R.id.guide_dot3); mLayoutBtn = (LinearLayout) findViewById(R.id.btn_layout); GuideFragment guideFragment1 = GuideFragment.newInstance(0); GuideFragment guideFragment2 = GuideFragment.newInstance(1); GuideFragment guideFragment3 = GuideFragment.newInstance(2); List<? extends Fragment> mFragmentList = Arrays.asList(guideFragment1, guideFragment2, guideFragment3); GuideFragmentPagerAdapter mAdapter = new GuideFragmentPagerAdapter(getSupportFragmentManager(), mFragmentList); mViewPager.setAdapter(mAdapter); //設置小圓點 mDotOne.setImageResource(R.mipmap.guide_dot_checked); mViewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() { @Override public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) { } @Override public void onPageSelected(int position) { mDotOne.setImageResource(R.mipmap.guide_dot_normal); mDotTwo.setImageResource(R.mipmap.guide_dot_normal); mDotThree.setImageResource(R.mipmap.guide_dot_normal); switch (position) { case 0: mDotOne.setImageResource(R.mipmap.guide_dot_checked); break; case 1: mDotTwo.setImageResource(R.mipmap.guide_dot_checked); break; case 2: mDotThree.setImageResource(R.mipmap.guide_dot_checked); break; } //設置當滑動到最後一頁時,顯示兩個按鈕 mLayoutBtn.setVisibility(position==2? View.VISIBLE:View.GONE); } @Override public void onPageScrollStateChanged(int state) { } }); } public static class GuideFragmentPagerAdapter extends FragmentPagerAdapter{ private List <? extends Fragment> fragments; public GuideFragmentPagerAdapter(FragmentManager fm,List<? extends Fragment> fragments) { super(fm); this.fragments = fragments; } @Override public Fragment getItem(int position) { return fragments.get(position); } @Override public int getCount() { return fragments.size(); } } }
參考資料:
VideoView繼承自SurfaceView,並實現了MediaPlayerControl接口。用於播放視頻文件。
幾個主要的方法:
下面繼續咱們的慕課網視頻引導效果的編碼:
@Nullable @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View guideView = inflater.inflate(R.layout.fragment_guide, container, false); mVideoView = (VideoView) guideView.findViewById(R.id.videoView); //獲取放置在raw文件夾得視頻的Uri Uri uri1 =Uri.parse("android.resource://" + getActivity().getPackageName() + "/" + R.raw.guide_1); Uri uri2 =Uri.parse("android.resource://" + getActivity().getPackageName() + "/" + R.raw.guide_2); Uri uri3 =Uri.parse("android.resource://" + getActivity().getPackageName() + "/" + R.raw.guide_3); Log.d(TAG,"1:"+uri1 +"\n2:"+uri2 +"\n3:"+uri3); mImageView = (ImageView) guideView.findViewById(R.id.wordView); switch (index){ case 0: mImageView.setImageResource(R.mipmap.guide_1); mVideoView.setVideoURI(uri1); break; case 1: mImageView.setImageResource(R.mipmap.guide_2); mVideoView.setVideoURI(uri2); break; case 2: mImageView.setImageResource(R.mipmap.guide_3); mVideoView.setVideoURI(uri3); break; } mVideoView.start(); //對VideoView的完成播放事件進行監聽,完成後再次播放以達到循環播放的效果 mVideoView.setOnCompletionListener(new MediaPlayer.OnCompletionListener() { @Override public void onCompletion(MediaPlayer mp) { mVideoView.start(); } }); Log.d(TAG,"onCreateView"); return guideView; }
運行效果:
看運行效果,發現一個問題,視頻的比例和手機的比例不一致致使右邊出現藍色長條。
這裏咱們繼承VideoView來自定義設置它的寬和高來解決這個問題:
代碼以下:
/** * Created by JohnTsai on 16/3/3. */ public class CustomWidthHeightVideoView extends VideoView{ private int mWidth = 0; private int mHeight = 0; public CustomWidthHeightVideoView(Context context) { super(context); } public CustomWidthHeightVideoView(Context context, AttributeSet attrs) { super(context, attrs); } public CustomWidthHeightVideoView(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); } public void setWidthHeight(int width,int height){ mWidth = width; mHeight = height; } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { if(mWidth>0&&mHeight>0) setMeasuredDimension(mWidth,mHeight); else super.onMeasure(widthMeasureSpec,heightMeasureSpec); } }
在onMeasure方法中,將咱們設置的寬和高經過setMeasuredDimension來自定義VideoView的寬和高。
//設置全屏播放 DisplayMetrics metrics = new DisplayMetrics(); getActivity().getWindowManager().getDefaultDisplay().getMetrics(metrics); mVideoView.setWidthHeight(metrics.widthPixels,metrics.heightPixels);
運行效果:
好,慕課網引導效果的編碼實現就到這。若是喜歡,請推薦一下。謝謝。
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