Android splash screen while loading MainActivity [

问题:

This question already has an answer here:

• How do I make a splash screen? 31 answers

So, I just read this question: How do I make a splash screen? But instead of adding a fixed delay (like in the top answer), I wanted to keep the splash screen on while the MainActivity (with a MapFragment) loads.

    public class SplashScreen extends Activity {
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_splash);

            Thread t = new Thread(new Runnable() {          
                @Override
                public void run() {
                    Intent i = new Intent(SplashScreen.this, MainActivity.class);
                    startActivity(i);
                    synchronized (this) {
                          try {
                            wait(3000);
                            System.out.println("Thread waited for 3 seconds");
                        } catch (InterruptedException e) {
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        }
                    }       
                }
            });
            try {
                t.start();
                t.join();
                finish();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
}

I added the wait(3000) line, because I noticed before that the thread didn't live for long. However, if I make it wait for longer, there's just a black screen that lasts longer. For some reason, the SplashScreen activity won't show the ImageView. What should I do? Thanks.

回答1:

make a splash screen like this:

while(counter < 1300) {
    try {
            Thread.sleep(1000);
        }catch(InterruptedException e) {
            e.printStackTrace();
        }
        counter+=100;
    }

    Intent intent = new Intent(SplashActivity.this, MainActivity.class);
    startActivity(intent);

Hope it helps!

EDIT: Anotehr way to make a splash would be like this:

Handler handler = new Handler();
handler.postDelayed(new Runnable() {
    public void run() {
         Intent intent = new Intent(getApplicationContext(), YourNextActivity.class);
         startActivity(intent);
    }
},3000); -> the splash will show for 3000 ms, you can reduce this.

回答2:

Easy way to do it..

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;

import com.example.tabs.R;

public class Splash extends Activity implements Runnable
{

    Thread mThread;

    @Override
    protected void onCreate(Bundle savedInstanceState) 
    {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.splash);

        mThread = new Thread(this);

        mThread.start();
    }

    @Override
    public void run() 
    {
        try
        {
            Thread.sleep(2000);
        }
        catch (Exception e) 
        {
            e.printStackTrace();
        }
        finally
        {
            startActivity(new Intent(Splash.this, MainActivity.class));

            finish();
        }
    }

}

splash.xml if you want to show a image

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:background="@drawable/splash" >


</LinearLayout>

Note if you want to do some UI operation in splash .Then you have to create a handler and update UI in it.

回答3:

The main thread cannot be blocked for a long time. You should use Handler to trigger another event if you want to start another event in 3 seconds. You can use sendMessageDelayed. In addition, startActivity should be called in main thread.