XML文件如下：<?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"><RelativeLayout android:id="@+id/main" android:layout_width="fill_parent" android:layout_height="fill_parent" > <LinearLayout android:id="@+id/imglayout" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical"> <ImageView android:id="@+id/imageView" android:src="@drawable/imgqr" android:layout_width="fill_parent" android:layout_height="wrap_content"/> </LinearLayout> <LinearLayout android:id="@+id/bottom_panel" android:layout_width="fill_parent" android:layout_height="wrap_content" android:orientation="horizontal" android:layout_alignParentBottom="true" > <Button android:id="@+id/ZoomInButton" android:layout_width="0dp" android:layout_height="wrap_content" android:layout_weight="1" android:layout_gravity="center_vertical" android:text="Zoom In" /> <Button android:id="@+id/ZoomOutButton" android:layout_width="0dp" android:layout_height="wrap_content" android:layout_weight="1" android:layout_gravity="center_vertical" android:text="Zoom Out" /> </LinearLayout> </RelativeLayout></LinearLayout>