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?
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
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。
Create an activity: Splash Create a layout XML file: splash.xml Put UI components in the splash.xml layout so it looks how you want your Splash.java may look like this: public class Splash extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.splash); int secondsDelayed = 1; new Handler().postDelayed(new Runnable() { public void run() { startActivity(new Intent(Splash.this, ActivityB.class)); finish(); } }, secondsDelayed * 1000); } } change ActivityB.class to whichever activity you want to start after the splash screen check your manifest file and it should look like
<活动 android: name = "。屏” android: label = " @string / app_name " > > < /活动 <活动 android: name = "。飞溅” android: label = " @string / title_activity_splash_screen " > <意图过滤器> <action android:name="android.intent.action. main " /> <category android:name="android.intent.category. launcher " /> < /意图过滤器> > < /活动
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
在Kotlin中编写以下代码:-
Handler().postDelayed({
val mainIntent = Intent(this@SplashActivity, LoginActivity::class.java)
startActivity(mainIntent)
finish()
}, 500)
希望这对你有所帮助,谢谢........
public class SplashActivity extends Activity {
Context ctx;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ctx = this;
setContentView(R.layout.activity_splash);
Thread thread = new Thread(){
public void run(){
try {
sleep(3000);
} catch (InterruptedException e) {
e.printStackTrace();
}
Intent in = new Intent(ctx,MainActivity.class);
startActivity(in);
finish();
}
};
thread.start();
}
}