Android开发-DesignDemo-AndroidStudio(八)CoordinatorDemo(3)

实现ActionBar隐藏显示，TextView悬停条目

记得styles.xml里，把主题设置为NoActionBar

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">

    <!--enterAlwaysCollapsed 第一条上拉至第一条数据才出现ActionBar-->
    <!--enterAlways 只要上拉就出现ActionBar-->
    <android.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:theme="@style/Widget.AppCompat.ActionBar">
        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?actionBarSize"
            app:layout_scrollFlags="scroll|enterAlwaysCollapsed"/>
        <TextView
            android:text="悬停条目"
            android:textColor="#ffffff"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />
    </android.support.design.widget.AppBarLayout>

    <android.support.v7.widget.RecyclerView
        android:id="@+id/recycler_1"
        app:layout_behavior="@string/appbar_scrolling_view_behavior"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layoutManager="LinearLayoutManager" />

    <TextView
        android:clickable="true"
        android:id="@+id/textView_1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="100dp"
        android:layout_marginLeft="100dp"
        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>

跟上一篇博文相比，java部分没有改变，以下是java部分。

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.support.v7.widget.Toolbar;
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);


        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
    }
}

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();
    }
}

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
        }
    }
}