我想让我的应用看起来更专业,所以我决定添加一个启动画面。

我应该如何进行实现呢?


当前回答

有时用户打开SplashActivity并立即退出,但应用程序仍然在SPLASH_SCREEN_DISPLAY_LENGTH后转到MainActivity。

为了防止它:在SplashActivity中,你应该在移动到MainActivity之前检查SplashActivity是否结束

public class SplashActivity extends Activity {

    private final int SPLASH_SCREEN_DISPLAY_LENGTH = 2000;

    @Override
    public void onCreate(Bundle icicle) {
        ...
        new Handler().postDelayed(new Runnable() {
            @Override
            public void run() {

                if (!isFinishing()) {//isFinishing(): If the activity is finishing, returns true; else returns false.
                    startActivity(new Intent(SplashActivity.this, MainActivity.class));
                    finish();
                }

            }, SPLASH_SCREEN_DISPLAY_LENGTH);
        }                             
   }                                
}

希望这对你有所帮助

其他回答

     - Add in SplashActivity 

   public class SplashActivity extends Activity {

       private ProgressBar progressBar;
       int i=0;
       Context context;
       private GoogleApiClient googleApiClient;

       @Override
       protected void onCreate(Bundle savedInstanceState) {
           super.onCreate(savedInstanceState);
           setContentView(R.layout.activity_splash);
           context = this;

           new Handler().postDelayed(new Runnable() {
               @Override
               public void run() {
                   startActivity(new Intent(Splash.this, LoginActivity.class));
                   finish();
               }
           }, 2000);

       }

   }

  - Add in activity_splash.xml

   <RelativeLayout
   xmlns:android="http://schemas.android.com/apk/res/android"
       xmlns:tools="http://schemas.android.com/tools"
       xmlns:custom="http://schemas.android.com/apk/res-auto"
       android:background="@color/colorAccent"
       android:layout_width="match_parent"
       android:layout_height="match_parent"
       tools:context=".Splash">

       <ImageView
           android:id="@+id/ivLogo"
           android:layout_width="match_parent"
           android:layout_height="match_parent"
           android:src="@mipmap/icon_splash"
           android:layout_centerHorizontal="true"
           android:layout_centerVertical="true"/>


       <ProgressBar
           android:id="@+id/circle_progress"
           style="?android:attr/progressBarStyleHorizontal"
           android:layout_width="fill_parent"
           android:layout_height="wrap_content"
           android:layout_alignParentBottom="true"
           android:layout_marginBottom="5dp"
           android:max="100"
           android:progressTint="@color/green"
           android:visibility="visible" />

   </RelativeLayout>

  - Add in AndroidManifest.xml

    <activity android:name="ex.com.SplashActivity">
               <intent-filter>
                   <action android:name="android.intent.action.MAIN" />

                   <category android:name="android.intent.category.LAUNCHER" />
               </intent-filter>
           </activity>

以上所有的答案都非常好。但是存在内存泄漏的问题。 这个问题在Android社区通常被称为“泄露活动”。这到底是什么意思呢?

当配置发生变化时,比如方向变化,Android会销毁Activity并重新创建它。通常,垃圾收集器只会清除旧Activity实例的已分配内存,一切正常。

“泄漏一个活动”指的是垃圾收集器无法清除旧活动实例的已分配内存的情况,因为它被(强)引用于一个活动实例外的对象。每个Android应用程序都分配了特定数量的内存。当垃圾回收器不能释放未使用的内存时,应用程序的性能将逐渐下降,最终崩溃并出现OutOfMemory错误。

如何确定应用程序是否泄漏内存?最快的方法是在Android Studio中打开内存选项卡,并在改变方向时注意分配的内存。 如果分配的内存一直在增加而不减少,那么就有内存泄漏。

1.当用户改变方向时内存泄漏。

首先,你需要在布局资源splashscreen.xml文件中定义启动画面

启动画面活动的示例代码。

public class Splash extends Activity {
 // 1. Create a static nested class that extends Runnable to start the main Activity
    private static class StartMainActivityRunnable implements Runnable {
        // 2. Make sure we keep the source Activity as a WeakReference (more on that later)
        private WeakReference mActivity;

        private StartMainActivityRunnable(Activity activity) {
         mActivity = new WeakReference(activity);
        }

        @Override
        public void run() {
         // 3. Check that the reference is valid and execute the code
            if (mActivity.get() != null) {
             Activity activity = mActivity.get();
             Intent mainIntent = new Intent(activity, MainActivity.class);
             activity.startActivity(mainIntent);
             activity.finish();
            }
        }
    }

    /** Duration of wait **/
    private final int SPLASH_DISPLAY_LENGTH = 1000;

    // 4. Declare the Handler as a member variable
    private Handler mHandler = new Handler();

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(icicle);
        setContentView(R.layout.splashscreen);

        // 5. Pass a new instance of StartMainActivityRunnable with reference to 'this'.
        mHandler.postDelayed(new StartMainActivityRunnable(this), SPLASH_DISPLAY_LENGTH);
    }

    // 6. Override onDestroy()
    @Override
    public void onDestroy() {
     // 7. Remove any delayed Runnable(s) and prevent them from executing.
     mHandler.removeCallbacksAndMessages(null);

     // 8. Eagerly clear mHandler allocated memory
     mHandler = null;
    }
}

欲了解更多信息,请点击此链接

public class MainActivity extends Activity {

@Override

public void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    Thread t=new Thread()
    {

        public void run()
        {   

            try {

                sleep(2000);
                finish();
                Intent cv=new Intent(MainActivity.this,HomeScreen.class/*otherclass*/);
                startActivity(cv);
            } 

            catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    };
    t.start();
}

一种方法是通过创建FullScreenActivity/EmptyActivity(例如SplashScreenActivity),并将其设置为打开应用程序时显示的第一个活动。在AndroidManifest.xml中添加以下内容到您的活动

 <intent-filter>
        <action android:name="android.intent.action.MAIN" />
        <category android:name="android.intent.category.LAUNCHER" />
</intent-filter>

然后,您可以设置一个处理程序,在几秒钟后取消此活动。

new Handler().postDelayed(new Runnable() {
            @Override
            public void run() {
                Intent i= new Intent(SplashScreenActivity.this,MainActivity.class);
                startActivity(i); //start new activity 
                finish();
            }
        }, 3000); //time in milliseconds

其次,如果你不想创建一个单独的活动,你可以在MainActivity上膨胀一个布局,并将布局可见性设置为GONE,或者在几毫秒后在现有的启动画面布局上膨胀主布局。

简单的代码,它的工作:)简单的飞溅

int secondsDelayed = 1;
    new Handler().postDelayed(new Runnable() {
        public void run() {
            startActivity(new Intent(LoginSuccessFull.this, LoginActivity.class));
            finish();
        }
    }, secondsDelayed * 1500);