Question

我想使用AsyncTask创建启动画面。具体来说，在doInBackground（）方法中，我使用静态方法Thread.sleep（），然后创建了一个intent，将app重定向到另一个activity。我没有收到任何错误，但该应用并没有改变活动。我的代码是：

/***This class redirects the user to the 'MainActivity'. ***/
class RedirectToMainActivityTask extends AsyncTask<Void, Void, Void>
{
    protected Void doInBackground(Void... params)
    {
        try 
        {
            Thread.sleep( 2 * 1000 );
        }
        catch ( InterruptedException e )
        {
            Log.e( "MAINACTIVITY-ERROR", e.getMessage());
            showTheError( "Error while starting MainActivity: " + e.getMessage() );
        }

        Intent intent = new Intent( getApplicationContext(), MainActivity.class );
        intent.addFlags( Intent.FLAG_ACTIVITY_CLEAR_TOP );
        startActivity( intent );

        finish();           
        return null;
    }       
}

Answer 1

您是否尝试过使用处理程序？：

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

        Intent intent = new Intent( getApplicationContext(), MainActivity.class );
        intent.addFlags( Intent.FLAG_ACTIVITY_CLEAR_TOP );
        startActivity( intent )
            }
        }, 2000);   //time you want to wait until MainActivity start

Answer 2

尝试将以下代码放在OnPostExecute（）方法

中

    Intent intent = new Intent( getApplicationContext(), MainActivity.class );
    intent.addFlags( Intent.FLAG_ACTIVITY_CLEAR_TOP );
    startActivity( intent );

Answer 3

确保您在清单中添加了活动

 <activity android:name="com.example.listissue.SecondActivity"/>

也不要打电话给完（）

private class RedirectToMainActivityTask extends AsyncTask<Void, Void, Void>
{
    protected Void doInBackground(Void... params)
    {
        try 
        {
            Thread.sleep( 2 * 1000 );
        }
        catch ( InterruptedException e )
        {
            e.printStackTrace();
        }
        return null;
    } 

    @Override
    protected void onPostExecute(Void result)
    {
          Intent intent = new Intent( getApplicationContext(), SecondActivity.class );
          intent.addFlags( Intent.FLAG_ACTIVITY_CLEAR_TOP );
          startActivity( intent );
    }

}

使用AsyncTask进行休眠

3 个答案: