ImageView as a splash screen not working

问题

My android app takes some time to initialize, and I'd like to show a splash image before the loading screen appears and hide it afterwards. I searched through stackoverflow and found some solutions. I tried to follow this tutorial, that explains how to implement a proper splash screen that starts within a splash activity, but it didn't solve my problem, because there was still a several seconds black screen between the splash screen and the loading screen (which renders from a separate thread of C++ code, and has to initialize a bunch of things before render starts, please don't ask to change that part, it's a crossplatform C++ engine). Next I experimented with a ProgressDialog taken from here, started it in onCreate of the main activity and hided when C++ part starts actual rendering, and it worked fine except not being a splash image. But the timing was exactly what I need. Then I replaced it with an ImageView and it didn't work (no image is shown).

protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    //...
    mImageView = new ImageView(this);
    mImageView.setScaleType(ScaleType.FIT_XY);
    mImageView.setImageResource(R.drawable.splash_bg);
    setContentView(mImageView);
}

splash_bg.png is put into res/drawable folder and shows fine from the splash activity. What is missing?

回答1:

xml for splash screen.  

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@drawable/ic_splash_screen" />

</RelativeLayout>

In MainActivity 



public class Splash extends Activity {

    private final int SPLASH_DISPLAY_LENGHT = 1000;

    @Override
    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);
        setContentView(R.layout.splashscreen);

        new Handler().postDelayed(new Runnable() {
            @Override
            public void run() {
                Intent mainIntent = new Intent(Splash.this,
                        MainActivity.class);
                Splash.this.startActivity(mainIntent);
                Splash.this.finish();
            }
        }, SPLASH_DISPLAY_LENGHT);
    }
}

回答2:

You should made theme for your splash activity like:

<style name="AppTheme.Splash" parent="YOURMAIN_THEME">
        <item name="android:windowBackground">@drawable/splash_bg</item>
</style>

And create your splash in drawable directory splash_bg.xml like:

<?xml version="1.0" encoding="utf-8"?>
<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:drawable="@drawable/splash_background"/>
    <item
        android:top="30dp">
        <bitmap
            android:gravity="top"
            android:src="@drawable/demo_logo"
            />
    </item>
    <item>
        <bitmap
            android:gravity="center"
            android:src="@drawable/demo_emlogo"/>
    </item>
</layer-list>

回答3:

Add this line in your onCreate(Bundle savedInstance) method:

mImageView = new ImageView(this);
    mImageView.setScaleType(ScaleType.FIT_XY);
    mImageView.setImageResource(R.drawable.splash_bg);
LayoutParams imageViewLayoutParams 
         = new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
        mImageView.setLayoutParams(imageViewLayoutParams);

来源：https://stackoverflow.com/questions/36915882/imageview-as-a-splash-screen-not-working

标签

android

android-layout

imageview