How to make dialog background image not expand dia

问题:

In my android project, when I set a background for a dialog in the xml code (the dialog uses a xml file for the layout), the dialog window size increases to fit the background image in it.

How can I set it so that the window size does not increase. It just ignores the background part that won't appear in the dialog. I guess the anchor of the image can be the center or the top left, doesn't matter.

Does anyone know how to do this?

Thanks.

回答1:

If you are setting it in an xml, you can just set the width and height to a set amount, like this:

    android:layout_width="100dp"
    android:layout_height="50dp"

or, better yet, use dimensions so you can adjust with different layouts. Or you can set them manually like this below.

Here is a nifty little alorithm that Ram kiran used in this answer

AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setView(layout);
builder.setTitle("Title");
alertDialog = builder.create();
alertDialog.show();
alertDialog.getWindow().setLayout(600, 400); //Controlling width and height.

回答2:

I found the solution, see here: Scale down (or crop) dialog background in Android

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 xmlns:android="http://schemas.android.com/apk/res/android">
<ImageView
  android:src="@drawable/back_dialog"
  android:scaleType="fitXY"
  android:layout_width="0dp"
  android:layout_height="0dp"
  android:layout_alignTop="@+id/dialog_layout_main"
  android:layout_alignBottom="@id/dialog_layout_main"
  android:layout_alignLeft="@id/dialog_layout_main"
  android:layout_alignRight="@id/dialog_layout_main" />
<LinearLayout 
  android:id="@+id/dialog_layout_main"
  android:layout_width="match_parent"
  android:layout_height="wrap_content">
   .........
</LinearLayout>
</RelativeLayout>

回答3:

Either set layout width and height for the parent layout static or do it for the ImageView. Setting match_parent, wrap_content or fill_parent(deprecated) will make dialog to expand to ImageView.