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
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........
其他回答
你可以在你的onCreate方法中添加这个
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
// going to next activity
Intent i=new Intent(SplashScreenActivity.this,MainActivity.class);
startActivity(i);
finish();
}
},time);
初始化你的时间值在毫秒,因为你想…
private static int time=5000;
欲了解更多详细信息,请从此链接下载完整代码…
https://github.com/Mr-Perfectt/Splash-Screen
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
Create an Activity SplashScreen.java public class SplashScreen extends Activity { protected boolean _active = true; protected int _splashTime = 3000; // time to display the splash screen in ms @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.splashscreen); Thread splashTread = new Thread() { @Override public void run() { try { int waited = 0; while (_active && (waited < _splashTime)) { sleep(100); if (_active) { waited += 100; } } } catch (Exception e) { } finally { startActivity(new Intent(SplashScreen.this, MainActivity.class)); finish(); } }; }; splashTread.start(); } } splashscreen.xml will be like this <?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="600px" android:layout_height="1024px" android:background="#FF0000"> </RelativeLayout>
另一种方法是使用CountDownTimer实现
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.splashscreen);
new CountDownTimer(5000, 1000) { //5 seconds
public void onTick(long millisUntilFinished) {
mTextField.setText("seconds remaining: " + millisUntilFinished / 1000);
}
public void onFinish() {
startActivity(new Intent(SplashActivity.this, MainActivity.class));
finish();
}
}.start();
}
一个超级灵活的启动屏幕如何,可以使用相同的代码,并在AndroidManifest.xml中定义,因此代码永远不需要更改。我通常开发代码库,不喜欢定制代码,因为它很草率。
<activity
android:name=".SplashActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<meta-data android:name="launch_class" android:value="com.mypackage.MyFirstActivity" />
<meta-data android:name="duration" android:value="5000" />
</activity>
然后SpashActivity本身查找“launch_class”的元数据,然后创建Intent本身。元数据“持续时间”定义了启动画面持续的时间。
public class SplashActivity extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.activity_splash);
ComponentName componentName = new ComponentName(this, this.getClass());
try {
Bundle bundle = null;
bundle = getPackageManager().getActivityInfo(componentName, PackageManager.GET_META_DATA).metaData;
String launch_class = bundle.getString("launch_class");
//default of 2 seconds, otherwise defined in manifest
int duration = bundle.getInt("duration", 2000);
if(launch_class != null) {
try {
final Class<?> c = Class.forName(launch_class);
new Handler().postDelayed(new Runnable() {
@Override
public void run() {
Intent intent = new Intent(SplashActivity.this, c);
startActivity(intent);
finish();
}
}, duration);
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
}
} catch (PackageManager.NameNotFoundException e) {
e.printStackTrace();
}
}
}