目录
安卓入门
三、布局
1、LinearLayout
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:divider="@drawable/ic_baseline_ac_unit_24" ：分割线
android:dividerPadding="10dp" ：设置分隔线的padding
android:gravity="center_vertical" ：控制组件所包含的子元素的对齐方式，可多个组合
android:orientation="vertical" ：布局中组件的排列方式
android:showDividers="middle" ：设置分隔线所在的位置，none（无），beginning（开始），end（结束），middle（每两个组件间）
>
<LinearLayout
android:layout_width="100dp"
android:layout_height="100dp"
android:layout_gravity="center" ：控制该组件在父容器里的对齐方式
android:layout_weight="1" ：（权重）该属性是用来等比例的划分区域
android:background="#ffff0000" ：为该组件设置一个背景图片，或者是直接用颜色覆盖
/>
<LinearLayout
android:layout_width="100dp"
android:layout_height="100dp"
android:background="#ff00ff00" />
<LinearLayout
android:layout_width="100dp"
android:layout_height="100dp"
android:background="#ff0000ff" />
</LinearLayout>
2、RelativeLayout
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:padding="10dp">
<RelativeLayout
android:id="@+id/layout1"
android:layout_width="100dp"
android:layout_height="100dp"
android:layout_alignParentBottom="true" ：对齐父容器底部
android:layout_centerHorizontal="true" ：中间水平方向
android:background="@color/red"
/>
<RelativeLayout
android:layout_width="100dp"
android:layout_height="100dp"
android:layout_above="@id/layout1" ：参照布局的上方
android:layout_margin="10dp"
android:layout_toRightOf="@id/layout1" ：参照布局的右边
android:background="@color/green"
/>
</RelativeLayout>
3、FrameLayout
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<FrameLayout
android:layout_width="100dp"
android:layout_height="100dp"
android:background="@color/red"
android:foreground="@drawable/ic_baseline_ac_unit_24" ：设置前景
android:foregroundGravity="right|bottom" ：设置前景位置
/>
</FrameLayout>
4、TableLayout
<TableLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:collapseColumns="0" ：设置需要被隐藏的列的序号，从0开始
android:shrinkColumns="1" ：设置允许被拉伸的列的列序号，从0开始
android:stretchColumns="1" ：设置允许被收缩的列的列序号，从0开始
>
<TableRow>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_column="1" ：显示在第几列
android:layout_span="2" ：横向跨几列
android:background="@color/green"
android:text="单元格" />
</TableRow>
</TableLayout>
5、GridLayout
<GridLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:columnCount="2" ：设置行的显示个数
android:orientation="vertical" ：设置水平显示还是垂直显示
android:rowCount="2" ：设置列的显示个数
>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_row="1" ：显示在第几行
android:layout_rowSpan="2" ：横向跨几行
android:layout_rowWeight="1" ：纵向剩余空间分配方式
android:layout_column="1" ：显示在第几列
android:layout_columnSpan="2" ：横向跨几列
android:layout_columnWeight="1" ：横向剩余空间分配方式
android:layout_gravity="fill" ：在网格中的显示位置
android:background="@color/green"
android:text="单元格" />
</GridLayout>
四、列表
1、ListView
- activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<!--ListView的layout_height属性值固定为match_parent-->
<ListView
android:id="@+id/lv"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
- list_item.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:id="@+id/tv"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="30sp" />
</LinearLayout>
- MainActivity
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Integer[] data = {5, 8, 3, 4, 9, 2, 7, 6, 1, 5, 8, 3, 4, 9, 2, 7, 6, 1, 5, 8, 3, 4, 9, 2, 7, 6, 1, 5, 8, 3, 4, 9, 2, 7, 6, 1};
Context context = this;
ListView listView = findViewById(R.id.lv);
listView.setAdapter(new BaseAdapter() {
@Override
public int getCount() {
return data.length;
}
@Override
public Object getItem(int position) {
return null;
}
@Override
public long getItemId(int position) {
return position;
}
final class ViewHolder {
TextView textView;
}
/**
* 参数2：当条目View对象不在屏幕显示的时候，此对象不会立即销毁，而是作为历史缓存View对象，可重复使用。
*/
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder viewHolder;
if (convertView == null) {
viewHolder = new ViewHolder();
/**
* inflate俗称打气筒，是个View对象，有三种方式将xml转成打气筒对象
*
* 方式一：View.inflate(getApplicationContext(), R.layout.list_item, null);
*
* 方式二：LayoutInflater.from(getApplicationContext()).inflate(R.layout.list_item, null);
*
* 方式三：LayoutInflater inflate = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
* inflate.inflate(R.layout.list_item, null);
*/
convertView = LayoutInflater.from(context).inflate(R.layout.list_item, parent, false);
/**
* 不同的xml，可以用相同的id
*/
viewHolder.textView = convertView.findViewById(R.id.tv);
convertView.setTag(viewHolder);
} else {
viewHolder = (ViewHolder) convertView.getTag();
}
viewHolder.textView.setText("林志玲" + data[position]);
return convertView;
}
});
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Log.e("ll", position + "");
}
});
}
}
2、RecyclerView
- build.gradle(:app)
dependencies {
// 添加Recyclerview依赖包
implementation 'androidx.recyclerview:recyclerview:1.1.0'
}
- activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<androidx.recyclerview.widget.RecyclerView
android:id="@+id/rv"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</LinearLayout>
- recyclerview_item.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:id="@+id/tv"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textSize="30sp" />
</LinearLayout>
- MyAdapter
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {
private Integer[] data;
private Context context;
public MyAdapter(Integer[] data, Context context) {
this.data = data;
this.context = context;
}
@NonNull
@Override
public MyViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
View itemView = View.inflate(context, R.layout.recyclerview_item, null);
return new MyViewHolder(itemView);
}
@Override
public void onBindViewHolder(@NonNull MyViewHolder holder, int position) {
if (position % 4 == 0) {
holder.tv.setText("孟美岐，黄婷婷" + data[position]);
} else {
holder.tv.setText("鞠婧祎" + data[position]);
}
}
@Override
public int getItemCount() {
return data.length;
}
public class MyViewHolder extends RecyclerView.ViewHolder {
private TextView tv;
public MyViewHolder(@NonNull View itemView) {
super(itemView);
tv = itemView.findViewById(R.id.tv);
itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if (mOnItemClickListener != null) {
mOnItemClickListener.onRecyclerItemClick(getAdapterPosition());
}
}
});
}
}
private OnRecyclerItemClickListener mOnItemClickListener;
public void setmOnItemClickListener(OnRecyclerItemClickListener listener) {
mOnItemClickListener = listener;
}
public interface OnRecyclerItemClickListener {
void onRecyclerItemClick(int position);
}
}
- MainActivity
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Integer[] data = {5, 8, 3, 4, 9, 2, 7, 6, 1, 5, 8, 3, 4, 9, 2, 7, 6, 1, 5, 8, 3, 4, 9, 2, 7, 6, 1, 5, 8, 3, 4, 9, 2, 7, 6, 1};
RecyclerView recyclerView = findViewById(R.id.rv);
// 线性布局
// LinearLayoutManager linearLayoutManager = new LinearLayoutManager(this);
// recyclerView.setLayoutManager(linearLayoutManager);
// 网格布局
// GridLayoutManager gridLayoutManager = new GridLayoutManager(this, 3);
// recyclerView.setLayoutManager(gridLayoutManager);
// 瀑布流
StaggeredGridLayoutManager staggeredGridLayoutManager = new StaggeredGridLayoutManager(3, LinearLayout.VERTICAL);
recyclerView.setLayoutManager(staggeredGridLayoutManager);
MyAdapter myAdapter = new MyAdapter(data, this);
recyclerView.setAdapter(myAdapter);
myAdapter.setmOnItemClickListener(new MyAdapter.OnRecyclerItemClickListener() {
@Override
public void onRecyclerItemClick(int position) {
Log.e("ll", position + "");
}
});
}
}
