布局主要代码

Activity_main:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/container"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:background="@drawable/bg2" >

<Button         android:id="@+id/button2"         android:layout_width="fill_parent"         android:layout_height="wrap_content"         android:layout_alignParentLeft="true"         android:layout_below="@+id/button1"         android:text="错题巩固" />

<Button         android:id="@+id/button3"         android:layout_width="fill_parent"         android:layout_height="wrap_content"         android:layout_alignParentLeft="true"         android:layout_below="@+id/button2"         android:text="退出" />

<Button         android:id="@+id/button1"         android:layout_width="fill_parent"         android:layout_height="wrap_content"         android:layout_alignParentLeft="true"         android:layout_alignParentTop="true"         android:layout_marginTop="148dp"         android:text="开始" />

</RelativeLayout>

CAL_MAIN:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/RelativeLayout1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/bg2"
    android:orientation="vertical" >

<Button
        android:id="@+id/button4"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_above="@+id/textView2"
        android:layout_alignParentLeft="true"
        android:layout_marginBottom="18dp"
        android:text="确定" />

<TextView

android:id="@+id/textView1"

android:layout_width="fill_parent"

android:layout_height="50dp

"         android:layout_above="@+id/EditText1"

android:layout_centerHorizontal="true"

android:layout_marginBottom="30dp"

android:gravity="center"

android:textSize="20px"

android:editable="true" />

<EditText

android:id="@+id/EditText1"

android:layout_width="wrap_content"

android:layout_height="50dp"

android:layout_above="@+id/button4"

android:layout_centerHorizontal="true"

android:digits="1234567890.-"

android:ems="10"

android:numeric="decimal" >

<TextView

android:id="@+id/textView2"

android:layout_width="230dp"

android:layout_height="70dp"

android:layout_alignParentBottom="true"

android:layout_alignParentRight="true"

android:layout_marginBottom="135dp"

android:editable="true"

android:textSize="20px" />

<ImageView

android:id="@+id/imageView1"

android:layout_width="wrap_content"

android:layout_height="wrap_content"

android:layout_alignBottom="@+id/textView2"

android:layout_alignTop="@+id/textView2"

android:layout_alignParentLeft="true"

android:layout_toLeftOf="@+id/textView2"/>

</RelativeLayout>

<requestFocus />

</EditText>

SHOW_MAIN:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/LinearLayout1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    android:background="@drawable/bg2">

<LinearLayout
       android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:layout_gravity="center">

<LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_gravity="center" >

<TextView
                android:id="@+id/textView1"
                android:layout_width="93dp"
                android:layout_height="wrap_content"
                android:editable="true"
                android:text="" />

<EditText
                android:id="@+id/EditText1"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:digits="1234567890.-"
                android:ems="10"
                android:numeric="decimal"
                android:text="" >

<requestFocus />
            </EditText>
        </LinearLayout>

<Button
        android:id="@+id/button6"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="确定" />
        <Button
        android:id="@+id/button7"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="下一题" />
        <Button

android:id="@+id/button8"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="从错题库删除" />
        <Button
        android:id="@+id/button9"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="返回" />
  <LinearLayout
       android:layout_width="fill_parent"
      android:layout_height="match_parent"
      android:orientation="horizontal">
            <ImageView

android:id="@+id/imageView2"

android:layout_width="fill_parent"

android:layout_height="70dp"

android:layout_weight="5"/>

<TextView

android:id="@+id/textView2"

android:layout_width="fill_parent"

android:layout_height="70dp"

android:layout_weight="3"

android:editable="true"

android:text="" />

</LinearLayout>

</LinearLayout>

</LinearLayout>