如何在一段时间后开始活动？

Question

我需要在一段时间后从当前活动开始活动.我编码如下.

public class FirstActivity extends Activity {

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


    new Timer().schedule(new TimerTask(){
        public void run() { 
            startActivity(new Intent(FirstActivity.this, SecondActivity.class));
        }
    }, 2000); 
}

但它不工作..继续崩溃..我的方法是否正确？我的清单文件如下

`

<uses-sdk
    android:minSdkVersion="8"
    android:targetSdkVersion="15" />

<application
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >
    <activity
        android:name=".FirstActivity"
        android:label="@string/title_activity_first" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <activity
        android:name=".SecondActivity"
        android:label="@string/title_activity_second" >
        <meta-data
            android:name="android.support.PARENT_ACTIVITY"
            android:value="com.example.first.FirstActivity" />
    </activity>
</application>

Answer 1

您可以使用Handlerclass postDelayed()方法执行此操作:

Handler mHandler = new Handler();
mHandler.postDelayed(new Runnable() {

    @Override
    public void run() {
        //start your activity here  
    }

}, 1000L);

其中1000L是以毫秒为单位的时间,在此之后将调用Runnable类中的代码.

试着用这个.

Answer 2

使用runOnUiThread从Timer启动活动:

new Timer().schedule(new TimerTask(){
        public void run() { 
         FirstActivity.this.runOnUiThread(new Runnable() {
            public void run() {
            startActivity(new Intent(FirstActivity.this, SecondActivity.class));
          }
        });
       }
    }, 2000);

Answer 3

我不知道你的代码有什么问题，但这应该有效：

private Handler mHandler = new Handler();
mHandler.postDelayed(mStartActivityTask, 2000);
private Runnable mStartActivityTask= new Runnable() {
    public void run() {
       // Start the Activity
    }
};