自定义dialog并设置margin

How to set margins to a custom dialog?

Margins don’t work for Dialogs, I imagine the top-level window view isn’t a layout type that supports margins. I’ve seen posts saying margins will work when defined as the Dialog’s style (rather than on the top-level view element), but this does not seem to work either.

What you need to do to work around the issue is to use an inset drawable for your Dialog background, and adjust any padding to account for the background’s extra inset. In the example below, I’ll just set left & right margins.

Dialog background drawable:

<?xml version="1.0" encoding="utf-8"?> <inset  xmlns:android="http://schemas.android.com/apk/res/android" <!-- a reference to your 'real' dialog background --> android:drawable="@drawable/dialog_background" <!-- add the margins --> android:insetRight="10dp" android:insetLeft="10dp"> </inset>

Dialog main view:

<?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="fill_parent" android:layout_height="wrap_content" <!-- top / bottom padding for the dialog --> android:paddingTop="5dp" android:paddingBottom="5dp" <!-- left / right padding must add the additional inset space to be consistent --> android:paddingLeft="15dp" android:paddingRight="15dp" <!-- reference to the inset background drawable --> android:background="@drawable/dialog_background_inset"> <!-- ...the rest of the layout... -->

You may also need to set the background colour of the Dialog itself to transparent. Add a colour resource like so:

<color name="transparent">#00000000</color>

And set the window background colour of the dialog to this (note: you can’t assign the colour directly, eclipse will complain)

<style name="Dialog" parent="android:style/Theme.Dialog">
    <item name="android:windowBackground">@color/transparent</item>
    <item name="android:windowNoTitle">true</item>
    <item name="android:windowIsFloating">true</item>
</style>

This style should be passed to your Dialog’s constructor as the theme argument, as in new Dialog(context, R.style.Dialog);

最后介绍一下InsetDrawable

InsetDrawable:

A Drawable that insets another Drawable by a specified distance. This is used when a View needs a background that is smaller than the View’s actual bounds.
It can be defined in an XML file with the element. For more information, see the guide to Drawable Resources.