Android making bottom tool bar not move to top of layout

问题

This is sort of a continuation of , where I wanted to get a warning text at the bottom of my screen (below my bottom tool bar) when off line. When in offline mode looks correct:

However when I hide the offline mode it pops to the top of the layout, like such (hiding everything I want to show):

I tried setting the bottom tool bar to android:layout_alignParentBottom="true", that does keep it from popping to the top when I hide the RelativeLayout with the TextView in it (Offline Mode) but then they overlay each other when I do not hide the Offline Mode.

Probably easy for someone a bit more experienced with Android UI than I. The XML layout currently looks like this:

<RelativeLayout
    android:id="@+id/mainLyt"
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ScrollView 
        android:id="@+id/formScrollView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_alignParentTop="true"
        android:layout_above="@+id/bottomBar" >
        <LinearLayout
            android:id="@+id/formLayout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:paddingLeft="10dp"
            android:paddingTop="15dp"
            android:paddingRight="10dp"
            android:paddingBottom="15dp"
            android:orientation="vertical" >
        </LinearLayout>

    </ScrollView>

    <RelativeLayout
        android:id="@+id/bottomBar"
        android:layout_height="wrap_content"
        android:layout_width="match_parent"
        android:orientation="horizontal"
        android:layout_above="@+id/bottomOffline" 
        android:background="@color/form_toolbar">

        <ImageButton
            android:id="@+id/btnPrev"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onClick="btnPrevClicked"
            android:layout_alignParentLeft="true"
            android:focusableInTouchMode="false"
            android:background="?android:attr/selectableItemBackground"
            android:src="@drawable/toolbar_prev"
            android:padding ="8dp"
            />

        <ImageButton
            android:id="@+id/btnIndex"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_toRightOf="@+id/btnPrev"
            android:onClick="btnIndexClicked"
            android:focusableInTouchMode="false"
            android:background="?android:attr/selectableItemBackground"
            android:src="@drawable/toolbar_index"
            android:padding ="8dp"
            />

        <ImageButton
            android:id="@+id/btnValidation"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_toRightOf="@+id/btnIndex"
            android:onClick="btnValidationClicked"
            android:focusableInTouchMode="false"
            android:background="?android:attr/selectableItemBackground"
            android:src="@drawable/toolbar_validate"
            android:padding ="8dp"
            />

        <ImageButton
            android:id="@+id/btnNext"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentRight="true"
            android:onClick="btnNextClicked"
            android:focusableInTouchMode="false"
            android:background="?android:attr/selectableItemBackground"
            android:src="@drawable/toolbar_next"
            android:padding ="8dp"
            />
    <!-- Some Buttons -->
    </RelativeLayout>

    <RelativeLayout
        android:id="@+id/bottomOffline"
        android:layout_width="match_parent"
        android:layout_height="34dp"
        android:layout_alignParentBottom="true"
        android:background="@color/orangelight"
        android:gravity="center_horizontal">

        <TextView
            android:id="@+id/offline"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:focusableInTouchMode="false"
            android:text="OFFLINE MODE"
            android:textStyle="bold"
            android:textColor="@color/white"
            android:padding ="8dp"
            />
    </RelativeLayout>

</RelativeLayout>

Thanks!

回答1:

Try wrapping the bottom views in a LinearLayout and remove the align fields from the two nested views

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:orientation="vertical">

<RelativeLayout
    android:id="@+id/bottomBar"
    android:layout_height="wrap_content"
    android:layout_width="match_parent"
    android:orientation="horizontal"
    android:background="@color/form_toolbar">

    <ImageButton
        android:id="@+id/btnPrev"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="btnPrevClicked"
        android:layout_alignParentLeft="true"
        android:focusableInTouchMode="false"
        android:background="?android:attr/selectableItemBackground"
        android:src="@drawable/toolbar_prev"
        android:padding ="8dp"
        />

    <ImageButton
        android:id="@+id/btnIndex"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_toRightOf="@+id/btnPrev"
        android:onClick="btnIndexClicked"
        android:focusableInTouchMode="false"
        android:background="?android:attr/selectableItemBackground"
        android:src="@drawable/toolbar_index"
        android:padding ="8dp"
        />

    <ImageButton
        android:id="@+id/btnValidation"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_toRightOf="@+id/btnIndex"
        android:onClick="btnValidationClicked"
        android:focusableInTouchMode="false"
        android:background="?android:attr/selectableItemBackground"
        android:src="@drawable/toolbar_validate"
        android:padding ="8dp"
        />

    <ImageButton
        android:id="@+id/btnNext"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:onClick="btnNextClicked"
        android:focusableInTouchMode="false"
        android:background="?android:attr/selectableItemBackground"
        android:src="@drawable/toolbar_next"
        android:padding ="8dp"
        />
    <!-- Some Buttons -->
</RelativeLayout>

<RelativeLayout
    android:id="@+id/bottomOffline"
    android:layout_width="match_parent"
    android:layout_height="34dp"
    android:background="@color/orangelight"
    android:gravity="center_horizontal">

    <TextView
        android:id="@+id/offline"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:focusableInTouchMode="false"
        android:text="OFFLINE MODE"
        android:textStyle="bold"
        android:textColor="@color/white"
        android:padding ="8dp"
        />
</RelativeLayout>

回答2:

Using Java, we can programatically set the view to align at the bottom when you're in online mode. The following could should be placed after the code that you use to remove the offline bar. (Since you didn't post your Java, I can't be more specific) I've assumed that the variable bottomBar is of type RelativeLayout and assigned through findViewById(R.id.bottomBar.

RelativeLayout.LayoutParams params = (RelativeLayout.LayoutParams)bottomBar.getLayoutParams();
params.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM);
bottomBar.setLayoutParams(params);

What this should do is set the ALIGN_PARENT_BOTTOM flag (android:layout_alignParentBottom="true" in XML) on the bottom bar so that it will stay at the bottom, even after the offline bar is removed. So, if you add that immediately after removing the offline bar, it will update the view and show the bar properly

来源：https://stackoverflow.com/questions/30224145/android-making-bottom-tool-bar-not-move-to-top-of-layout