我有一个非常基本但困难的问题，我有一个按钮固定在 View 底部，但在 recyclerview 容器下方。一旦容器大小增加，我希望按钮位于 recyclerview(可滚动)下方，而不是固定在 View 底部。有没有办法实现这一点？
我在网上查找了一些想法，但还没有找到任何类似的想法。
我基本上都在用
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/white"
android:clickable="false">
<android.support.design.widget.CoordinatorLayout
android:id="@+id/cl_root_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:clipChildren="false">
<LinearLayout
android:id="@+id/activity_g"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:elevation="0dp">
<android.support.v7.widget.Toolbar
android:id="@+id/toolbar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@color/white"
app:subtitleTextColor="@color/white"
app:titleTextAppearance="@style/Toolbar.TitleText"
app:titleTextColor="@color/white">
<TextView
android:id="@+id/nav_back_btn"
style="@style/Body1RegLeftBlack"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="20dp"
android:layout_marginStart="@dimen/activity_horizontal_margin"
android:gravity="center_horizontal"
android:background="@drawable/ic_backarrow" />
<TextView
android:id="@+id/g_main_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="18dp"
android:layout_marginTop="15dp"
android:letterSpacing="0.01"
android:gravity="center_horizontal"
android:text="@string/g"
android:textAppearance="@style/TextAppearance.Text.Roboto.Medium"
android:textColor="#de000000"
android:textSize="20sp"
android:textStyle="normal"
/>
</android.support.v7.widget.Toolbar>
</android.support.design.widget.AppBarLayout>
<android.support.v4.widget.NestedScrollView
android:id="@+id/info_scrollview"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<LinearLayout
android:id="@+id/infoContainer"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="@color/white"
android:clickable="false"
android:orientation="vertical">
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="30dp">
<TextView
android:id="@+id/info_location"
style="@style/Headline2LeftBlack"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="@dimen/activity_horizontal_margin"
android:textAppearance="@style/TextAppearance.Text.Chronicle"
android:textSize="28sp"
tools:text="@string/five_thirty_fifth_ave" />
<TextView
style="@style/Body1RegRightRed"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="@+id/info_location"
android:layout_alignParentEnd="true"
android:layout_marginEnd="@dimen/activity_horizontal_margin"
android:layout_toEndOf="@+id/info_location"
android:text="@string/location_change"
android:textAppearance="@style/TextAppearance.Text.Roboto.Regular"
android:visibility="gone" />
</RelativeLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="48dp"
android:layout_marginTop="44dp"
android:gravity="center_vertical"
android:weightSum="2">
<TextView
style="@style/Body1RegLeftBlack"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="16dp"
android:layout_weight="1"
android:id="@+id/g_start_date"
android:textAppearance="@style/TextAppearance.Text.Roboto.Regular"
android:text="@string/g_start_date" />
<TextView
style="@style/Body1RegRightBlack"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="16dp"
android:layout_weight="1"
android:id="@+id/g_start_time"
android:textAppearance="@style/TextAppearance.Text.Roboto.Regular"
android:text="@string/g_start_time" />
</LinearLayout>
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:background="@color/registerUserSeparatorColor" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="48dp"
android:gravity="center_vertical"
android:weightSum="2">
<TextView
style="@style/Body1RegLeftBlack"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="16dp"
android:layout_weight="1"
android:id="@+id/g_end_date"
android:textAppearance="@style/TextAppearance.Text.Roboto.Regular"
android:visibility="invisible"
android:text="@string/g_end_date" />
<TextView
style="@style/Body1RegRightBlack"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="16dp"
android:layout_weight="1"
android:id="@+id/g_end_time"
android:textAppearance="@style/TextAppearance.Text.Roboto.Regular"
android:text="@string/g_end_time" />
</LinearLayout>
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:background="@color/registerUserSeparatorColor" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="16dp"
android:layout_marginTop="28dp"
android:letterSpacing="0.01"
android:lineSpacingExtra="4sp"
android:paddingTop="30dp"
android:textAppearance="@style/TextAppearance.Text.Roboto.Medium"
android:textColor="@color/black"
android:textSize="20sp"
android:textStyle="normal"
android:text="@string/g" />
<android.support.v7.widget.RecyclerView
android:id="@+id/g_item_list"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:overScrollMode="never"
android:divider="@null"
tools:listitem="@layout/item_g"/>
<TextView
style="@style/Body1RegLeftRed"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="16sp"
android:layout_marginTop="20dp"
android:id="@+id/add_g"
android:lineHeight="22sp"
android:text="@string/add_g"
android:textSize="16sp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="16dp"
android:layout_marginTop="58dp"
android:letterSpacing="0.01"
android:lineSpacingExtra="4sp"
android:visibility="invisible"
android:textAppearance="@style/TextAppearance.Text.Roboto.Medium"
android:textColor="@color/black"
android:textSize="20sp"
android:textStyle="normal"
android:text="@string/arrival_notifications" />
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone"
android:id="@+id/text_message_container"
android:layout_marginStart="16dp">
<TextView
android:id="@+id/text_message"
style="@style/Body1RegLeftBlack"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="11dp"
android:textAppearance="@style/TextAppearance.Text.Roboto.Regular"
android:text="@string/text_message" />
<TextView
style="@style/Body2RegLeftGrey"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/text_message"
android:layout_marginTop="2dp"
android:id="@+id/tap_phone_number_text"
android:textAppearance="@style/TextAppearance.Text.Roboto.Regular"
android:text="@string/tap_to_add_a_phone_number" />
<android.support.v7.widget.SwitchCompat
android:id="@+id/text_message_switch"
style="@style/Color1SwitchStyle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:layout_centerVertical="true"
android:layout_marginEnd="16dp" />
</RelativeLayout>
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:layout_marginStart="16dp"
android:visibility="gone"
android:layout_marginTop="11dp"
android:background="@color/settingsSeparatorLineColor" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="16sp"
android:layout_marginTop="100dp"
android:textAppearance="@style/TextAppearance.Text.Roboto.Medium"
android:textStyle="normal"
android:letterSpacing="0.07"
android:lineSpacingExtra="0sp"
android:layout_gravity="center"
android:layout_marginBottom="30dp"
android:id="@+id/submit_btn"
android:text="@string/submit_list"
/>
</LinearLayout>
</android.support.v4.widget.NestedScrollView>
</LinearLayout>
</android.support.design.widget.CoordinatorLayout>
</android.support.design.widget.CoordinatorLayout>
上面的问题是，submit_list btn 不会保持固定，如果 recyclerview 增长但 View 中仍有足够的空间可用。
我想让按钮保持固定并且不滚动直到 recyclerview 的大小超出底部的某个限制(在屏幕上不再可见)，之后按钮相对于最后一个项目滚动recyclerview 的，不再与底部对齐。有什么想法吗？
举个形象的例子:
如您所见，初始屏幕的提交按钮与底部对齐，其余内容就位。当我添加更多用户时:
它仍然停留在底部，因为 recyclerview 项目仍在屏幕内
现在，只要我再添加一项，列表就会向上滚动:
正如我所看到的，我希望它位于 recyclerview 下方，而不是固定在屏幕底部(上面的屏幕截图来自它工作的 ios)，想知道我们是否可以为 android 做同样的事情？
最佳答案
您可以使用 ConstraintLayout
示例代码
layout file
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/myRecyclerView"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_margin="8dp"
app:layout_constraintBottom_toTopOf="@+id/btnBottom"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHeight_default="wrap"
app:layout_constraintHorizontal_chainStyle="packed"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintStart_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent" />
<Button
android:id="@+id/btnBottom"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginLeft="20dp"
android:layout_marginTop="12dp"
android:layout_marginRight="20dp"
android:padding="12dp"
android:text="Continue"
android:textAllCaps="false"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintStart_toStartOf="parent"
android:textColor="@android:color/white"
app:backgroundTint="@color/colorPrimary" />
</androidx.constraintlayout.widget.ConstraintLayout>
Activity code
public class MainActivity extends AppCompatActivity {
RecyclerView myRecyclerView;
ArrayList<String> arrayList = new ArrayList<>();
DataAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myRecyclerView = findViewById(R.id.myRecyclerView);
myRecyclerView.setLayoutManager(new LinearLayoutManager(this));
myRecyclerView.setHasFixedSize(true);
addDataToList();
adapter = new DataAdapter(this, arrayList);
myRecyclerView.setAdapter(adapter);
}
private void addDataToList() {
for (int i = 0; i < 5; i++) {
arrayList.add("NILU_PILU :-> " + i);
}
}
}
DataAdapter class
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import java.util.ArrayList;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
public class DataAdapter extends RecyclerView.Adapter<DataAdapter.ViewHolder> {
ArrayList<String> arrayList = new ArrayList<>();
private Context mContext;
public DataAdapter(Context mContext, ArrayList<String> arrayList) {
this.mContext = mContext;
this.arrayList = arrayList;
}
@NonNull
@Override
public ViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(mContext).inflate(R.layout.aaa, parent, false);
return new ViewHolder(view);
}
@Override
public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
holder.tvText.setText(arrayList.get(position));
}
@Override
public int getItemCount() {
return arrayList.size();
}
public class ViewHolder extends RecyclerView.ViewHolder {
TextView tvText;
public ViewHolder(@NonNull View itemView) {
super(itemView);
tvText = itemView.findViewById(R.id.tvText);
}
}
}
OUTPUTS
关于android - 一旦顶部的回收 View 变大，如何制作固定在布局滚动底部的按钮，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/56159855/