将布局放在底部并添加滚动条

Question

I have three Relative layouts in may app, on above another.

<RelativeLayout_1><CheckBox></CheckBox></RelativeLayout>
<RelativeLayout_2></RelativeLayout>
<RelativeLayout_3></RelativeLayout>

First is at top, and third is at bottom. When I click on check box in my first layout, second layout is visible/unvisible. How to achive that I always see third layout at bottom and put scrollbar at second when is visible ? ( Second have lot off content so when is visible, third layout is vanished ).

Answer 1

Try

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
   xmlns:android="http://schemas.android.com/apk/res/android"
   android:layout_width="fill_parent"
   android:layout_height="fill_parent"
   android:orientation="vertical"
   android:background="#888888"
   android:id="@+id/relativeLayout1">
   <RelativeLayout
      android:layout_height="wrap_content"
      android:id="@+id/relativeLayout2"
      android:layout_width="fill_parent"
      android:background="#404000"
      android:layout_alignParentTop="true">
      <CheckBox
         android:text="CheckBox"
         android:id="@+id/checkBox1"
         android:layout_width="wrap_content"
         android:onClick="myClickHandler"
         android:layout_height="wrap_content"></CheckBox>
      <CheckBox
         android:text="CheckBox"
         android:layout_height="wrap_content"
         android:id="@+id/checkBox2"
         android:onClick="myClickHandler"
         android:layout_alignParentRight="true"
         android:layout_width="wrap_content"></CheckBox>
   </RelativeLayout>
   <ScrollView
      android:id="@+id/scrollView1"
      android:layout_below="@+id/relativeLayout2"
      android:scrollbars="vertical"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content">
      <RelativeLayout
         android:layout_height="wrap_content"
         android:id="@+id/relativeLayout3"
         android:layout_width="fill_parent"
         android:background="#000040"
         android:orientation="vertical">
         <TextView
            android:layout_height="190dp"
            android:id="@+id/textView1"
            android:text="TextView1"
            android:layout_alignParentTop="true"
            android:background="#004000"
            android:layout_width="wrap_content"
            android:textSize="20pt"></TextView>
         <TextView
            android:layout_height="190dp"
            android:id="@+id/textView2"
            android:text="TextView2"
            android:layout_width="wrap_content"
            android:background="#000040"
            android:layout_below="@+id/textView1"
            android:textSize="20pt"></TextView>
         <TextView
            android:layout_height="190dp"
            android:id="@+id/textView3"
            android:text="TextView3"
            android:layout_width="wrap_content"
            android:background="#400000"
            android:layout_below="@+id/textView2"
            android:textSize="20pt"></TextView>
      </RelativeLayout>
   </ScrollView>
   <RelativeLayout
      android:layout_height="wrap_content"
      android:id="@+id/relativeLayout4"
      android:layout_width="fill_parent"
      android:layout_alignParentBottom="true">
      <TextView
         android:layout_height="wrap_content"
         android:id="@+id/textView4"
         android:text="I'm a text view in bottom Rel Layout"
         android:layout_alignParentTop="true"
         android:layout_width="wrap_content"
         android:background="#000000"></TextView>
   </RelativeLayout>
</RelativeLayout>

And for the click handler

public void myClickHandler(View target) {

   View rv = findViewById(R.id.scrollView1);
   CheckBox cb1 = (CheckBox) findViewById(R.id.checkBox1);
   CheckBox  cb2 = (CheckBox) findViewById(R.id.checkBox2);

   switch (target.getId()) {
      case R.id.checkBox1:
         cb2.setChecked(false);
         break;
      case R.id.checkBox2:
         cb1.setChecked(false);
         break;
   }
   rv.setVisibility(cb1.isChecked() ? View.VISIBLE : View.GONE);
}