列举至少3种Support包中提供的布局或工具

时间:2023-08-16 23:51:02

android.support.v7.widget.CardView

继承自FrameLayout并实现了圆角和阴影效果,常用于ListView或RecyclerView中Item布局的根节点 
示例代码:

<android.support.v7.widget.CardView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:android.support.v7.cardview="http://schemas.android.com/apk/res-auto"
android:id="@+id/item_cardView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:clickable="true"
android:elevation="4dp"
android:foreground="?android:attr/selectableItemBackground"
android.support.v7.cardview:cardBackgroundColor="#999"
android.support.v7.cardview:cardCornerRadius="15dp"
android.support.v7.cardview:cardElevation="15dp"
android.support.v7.cardview:contentPadding="0dp"> <TextView
android:id="@+id/item_textView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:padding="16dp"
android:text="@string/hello" />
</android.support.v7.widget.CardView>

 

com.android.support:recyclerview-v7包

recyclerview

高度解耦 , 异常灵活 , 可以用来代替ListView / GridView

相关类介绍: 
列举至少3种Support包中提供的布局或工具

使用步骤: 
1.导包 
2.在布局文件中添加RecyclerView 
3.在Java代码中实现RecyclerView, 至少要添加两个属性: 
recyclerView.setLayoutManager(new LinearLayoutManager(this));//指定布局管理器 
recyclerView.setAdapter(adapter); //指定Adapter 
4.Adapter的写法 
1)创建一个自定义的ViewHolder,在里面初始化Item的每一个控件 
2)让自定义的Adapt而继承RecyclerView.Adapter<传入自定义的ViewHolder> 
3)实现对应的方法

    <android.support.v7.widget.RecyclerView
android:id="@+id/app_taskview_recyclerview"
android:layout_width="wrap_content"
android:layout_height="475dip"/>
public class RecyclerAdapter extends RecyclerView.Adapter<RecyclerAdapter.ViewHolder> {
private Context context;
private ArrayList<String> list; public RecyclerAdapter(ArrayList<String> list, Context context) {
this.list = list;
this.context = context;
} @Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.recycler_item,
parent, false);
ViewHolder holder = new ViewHolder(view);
return holder;
} @Override
public void onBindViewHolder(ViewHolder holder, int position) {
String s = list.get(position);
holder.item_textView.setText(s);
} @Override
public int getItemCount() {
return list.size();
} public static class ViewHolder extends RecyclerView.ViewHolder {
private final TextView item_textView; public ViewHolder(View itemView) {
super(itemView);
item_textView = (TextView) itemView.findViewById(R.id.item_textView);
}
}
}

com.android.support:design包-

FloatingActionButton

漂浮的Button,该控件父类为ImageView,所以拥有ImageView的所有属性

效果: 
列举至少3种Support包中提供的布局或工具

常用属性 
android.support.design:fabSize=” ” 指定图标的大小 值:normal / mini 
android.support.design:elevation=”” 指定阴影的深度 int 
app:layout_anchor=” ” 指定显示坐标的锚点 
app:layout_anchorGravity=” ” 指定锚点的对齐方式

<android.support.design.widget.FloatingActionButton
android:id="@+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@mipmap/ic_launcher"
app:elevation = "10dp"
android:layout_alignParentBottom="true">
</android.support.design.widget.FloatingActionButton>

app包名为

xmlns:app="http://schemas.android.com/apk/res-auto"