Behavior的2种实现方式:
MainActivity.java:
package com.iwanghang.coordinatordemo; import android.support.design.widget.CoordinatorLayout; import android.support.design.widget.Snackbar; import android.support.design.widget.SwipeDismissBehavior; import android.support.v4.view.ViewCompat; import android.support.v7.app.AppCompatActivity; import android.os.Bundle; import android.support.v7.widget.RecyclerView; import android.view.View; import android.widget.TextView; import java.util.ArrayList; import java.util.List; import java.util.Locale; public class MainActivity extends AppCompatActivity { private TextView textView_1; private TextView textView_2; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); textView_1 = (TextView) findViewById(R.id.textView_1); textView_2 = (TextView) findViewById(R.id.textView_2); // 手动强转控件类型 CoordinatorLayout.LayoutParams params_1 = (CoordinatorLayout.LayoutParams) textView_1.getLayoutParams(); CoordinatorLayout.LayoutParams params_2 = (CoordinatorLayout.LayoutParams) textView_2.getLayoutParams(); // setBehavior 设置控件的行为 //params.setBehavior(); // SwipeDismissBehavior 实例化滑动删除行为 SwipeDismissBehavior<View> behavior = new SwipeDismissBehavior<>(); // 滑动删除行为监听 behavior.setListener(new SwipeDismissBehavior.OnDismissListener() { @Override public void onDismiss(View view) { // 当控件消失 // 在设置控件隐藏之前,其实控件只是透明,还可以滑动回来 view.setVisibility(View.GONE); // 设置控件隐藏 Snackbar.make(view,"删除控件",Snackbar.LENGTH_LONG) .setAction("撤销", new View.OnClickListener() { @Override public void onClick(View view) { textView_2.setVisibility(View.VISIBLE); // 设置控件显示 ViewCompat.animate(textView_2).alpha(1).start(); } }).show(); } @Override public void onDragStateChanged(int state) { // 当控件停止 } }); // 把滑动删除行为设置到textView控件上 params_2.setBehavior(behavior); RecyclerView recycler_1 = (RecyclerView) findViewById(R.id.recycler_1); List<String> list = new ArrayList<>(); for (int i = 0; i <100 ; i++) { list.add(String.format(Locale.CHINA,"第%03d条数据",i+1)); } recycler_1.setAdapter(new MyAdapter(this,list)); MyBehavior myBehavior = new MyBehavior(); params_1.setBehavior(myBehavior); } }MyBehavior.java:
package com.iwanghang.coordinatordemo; import android.content.Context; import android.support.design.widget.CoordinatorLayout; import android.support.v4.view.ViewCompat; import android.util.AttributeSet; import android.view.View; /** * 重写Behavior的方法 */ public class MyBehavior extends CoordinatorLayout.Behavior { /** * 实现下面3行方法 则可以通过 * app:layout_behavior="com.iwanghang.coordinatordemo.MyBehavior" * 来实现 MyBehavior */ public MyBehavior(Context context, AttributeSet attrs) { super(context, attrs); } public MyBehavior() { } // Behavior 开始滚动 @Override public boolean onStartNestedScroll(CoordinatorLayout coordinatorLayout, View child, View directTargetChild, View target, int nestedScrollAxes) { return true; // 为true,表示我们关心这个事件 } // Behavior 正在滚动 @Override public void onNestedPreScroll(CoordinatorLayout coordinatorLayout, View child, View target, int dx, int dy, int[] consumed) { super.onNestedPreScroll(coordinatorLayout, child, target, dx, dy, consumed); if (dy < 0){ // 向上滚动 ViewCompat.animate(child).scaleX(1).scaleY(1).start(); // 显示控件 }else { // 向下滚动 ViewCompat.animate(child).scaleX(0).scaleY(0).start(); // 隐藏控件 } } }MyAdapter.java:
package com.iwanghang.coordinatordemo; import android.content.Context; import android.support.v7.widget.RecyclerView; import android.view.ViewGroup; import android.widget.TextView; import java.util.List; public class MyAdapter extends RecyclerView.Adapter<RecyclerView.ViewHolder>{ private Context context; private List<String> list; public MyAdapter(Context context, List<String> list) { this.context = context; this.list = list; } public Context getContext() { return context; } public void setContext(Context context) { this.context = context; } public List<String> getList() { return list; } public void setList(List<String> list) { this.list = list; } @Override public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { TextView view = new TextView(context); return new RecyclerView.ViewHolder(view){}; } @Override public void onBindViewHolder(RecyclerView.ViewHolder holder, int position) { ((TextView) holder.itemView).setText(list.get(position)); } @Override public int getItemCount() { return list.size(); } }activity_main.xml:
<?xml version="1.0" encoding="utf-8"?> <android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" xmlns:app="http://schemas.android.com/apk/res-auto" android:id="@+id/activity_main" android:layout_width="match_parent" android:layout_height="match_parent" tools:context="com.iwanghang.coordinatordemo.MainActivity"> <android.support.v7.widget.RecyclerView android:id="@+id/recycler_1" android:layout_width="match_parent" android:layout_height="match_parent" app:layoutManager="LinearLayoutManager" ></android.support.v7.widget.RecyclerView> <TextView android:clickable="true" android:id="@+id/textView_1" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center|top" android:textSize="20sp" android:background="#f00" android:text="textView_1\nlist上下滚动显示隐藏\n通过setBehavior实现" /> <TextView android:clickable="true" android:id="@+id/textView_2" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center" android:textSize="20sp" android:background="#f00" android:text="textView_2\n向右滑动" /> <TextView app:layout_behavior="com.iwanghang.coordinatordemo.MyBehavior" android:clickable="true" android:id="@+id/textView_3" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_gravity="center|bottom" android:textSize="20sp" android:background="#f00" android:text="textView_3\nlist上下滚动显示隐藏\n指定layout_behavior实现" /> </android.support.design.widget.CoordinatorLayout>