如何以编程方式将我的imageView center_veritically放在FrameLayout上？

Question

我想把imageView放在FrameLayout的center_vertical上。但是，我做不到。我试过FrameLayout.LayoutParams，但它没有.addRule（）方法。

public class P023Deneme extends Activity { 
@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 

    FrameLayout frameLayout=new FrameLayout(this); 
    ImageView imageViewBackgroud=new ImageView(this); 
    imageViewBackgroud.setImageResource(R.drawable.sample_6); 

    ImageView imageViewLeftArrow=new ImageView(this); 
    imageViewLeftArrow.setImageResource(R.drawable.slidersolok_logo); 

    frameLayout.addView(imageViewBackgroud); 
    frameLayout.addView(imageViewLeftArrow,50,50); 
    setContentView(frameLayout); 


} 

}

Answer 1

做它在XML，而不是代码，它更容易

<?xml version="1.0" encoding="utf-8"?> 

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

    <ImageView 
     android:layout_width="wrap_content" 
     android:layout_height="wrap_content" 
     android:layout_gravity="center_vertical" 
     android:src="@drawable/background_drawable"/> 

    <ImageView 
     android:layout_width="50dp" 
     android:layout_height="50dp" 
     android:src="@drawable/arrow_drawable"/> 
</FrameLayout> 

如果您仍想以编程方式做到这一点，则：

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

    FrameLayout frameLayout=new FrameLayout(this); 
    ImageView imageViewBackgroud=new ImageView(this); 
    imageViewBackgroud.setImageResource(R.drawable.background); 

    ImageView imageViewLeftArrow=new ImageView(this); 
    imageViewLeftArrow.setImageResource(R.drawable.arrow); 

    FrameLayout.LayoutParams layoutParams = new FrameLayout.LayoutParams(FrameLayout.LayoutParams.WRAP_CONTENT, 
      FrameLayout.LayoutParams.WRAP_CONTENT, Gravity.CENTER_VERTICAL); 
    frameLayout.addView(imageViewBackgroud); 
    frameLayout.addView(imageViewLeftArrow, layoutParams); 
    setContentView(frameLayout); 
}