android - 调整和定位 RecyclerView 项目

Question

我正在使用 RecyclerView 在网格布局中显示项目。下面是模拟器的图像和我需要实现的期望结果。左侧(执行)图像是我的模拟器上的输出，而右侧(期望)是我想要实现的输出。

Activity 布局 XML

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:id="@+id/parentLayout"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:background="#d3c3c3">

 <include
    android:id="@+id/toolBarIncluded"
    layout="@layout/toolbar_new_layout" />


<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_below="@+id/toolBarIncluded"
    android:orientation="vertical"
    android:weightSum="1">

    <RelativeLayout

        android:id="@+id/recyclerAdView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_margin="10dp"
        android:layout_weight="0.65"
        android:background="#009688" />

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_below="@+id/recyclerAdView"
        android:layout_gravity="center"
        android:layout_weight="0.35"
        android:background="#00000000"
        android:gravity="center">

        <android.support.v7.widget.RecyclerView

            android:id="@+id/recyclerGridView"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_margin="2dp"
            android:background="#00000000"
            android:foregroundGravity="center" />

    </RelativeLayout>

</LinearLayout>

列表项 XML

 <?xml version="1.0" encoding="utf-8"?>
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 android:id="@+id/llGridItemLayout"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:layout_gravity="center"
 android:layout_margin="6dp"
 android:background="@drawable/drawable_grid_item_background"
 android:gravity="center"
 android:paddingStart="2dp"
 android:paddingEnd="2dp"
 android:orientation="vertical">

 <ImageView
    android:id="@+id/ivItemIcon"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:scaleType="fitCenter"
    android:src="@drawable/ic_new_receipt_wrong" />

  <TextView
    android:layout_marginTop="6dp"
    android:id="@+id/tvItemName"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:lines="1"
    android:text="My Complaints"
    android:textSize="14sp" />

 </LinearLayout>

Activity 代码 fragment

    gridLayoutManager = new GridLayoutManager(MainActivity.this, 3);
    recyclerView.setHasFixedSize(true);
    recyclerView.setLayoutManager(gridLayoutManager);
    recyclerView.setAdapter(demoDashAdapter);

适配器代码 fragment

int viewHeight ,viewWidth ;
public onCreateViewHolder(){
   viewHeight = viewGroup.getMeasuredHeight() / 4;
   viewWidth = viewGroup.getMeasuredWidth() / 3;
  ...
}

public onBindViewHolder(){

  viewHolder.itemLayout.setMinimumWidth(viewWidth);
  viewHolder.itemLayout.setMinimumHeight(viewHeight);
  ...
}

因此我的问题是，如何动态调整 recyclerView 中项目的大小。请注意，我使用的布局权重为 0.65 和 0.35 而不是 weightSum 1；

请指导我。

Answer 1

不要使用 RecyclerView.Adapter 来改变 View 的布局方式。这是 RecyclerView.LayoutManager 的职责。

您可以重写验证 View.LayoutParams 的方法以均匀分布大小:

 //customized GridLayoutManager
 gridLayoutManager = new GridLayoutManager(MainActivity.this, 3){
     @Override
     public boolean checkLayoutParams(RecyclerView.LayoutParams lp) {
         // force size of viewHolder here, this will override layout_height and layout_width from xml
         lp.height = getHeight() / getSpanCount();
         lp.width = getWidth() / getSpanCount();
         return true;
     }
 };
 recyclerView.setHasFixedSize(true);
 recyclerView.setLayoutManager(gridLayoutManager);