学习Android的新的UI控件Material Design（六）——CollapsingToolbarLayout实现可折叠式标题栏（综合）

开发工具：Android Studio

这篇文章是这个系列的一个总结，其中用到了前面的所有UI控件的知识，来实现一个图片，一个标题，和一个可以展开的文本信息，实现流畅的切换过程，具体的开发过程如下：

首先和创建一个FruitActivity和activity_fruit.xml的布局具体代码如下：

activity_fruit.xml代码

xml version="1.0" encoding="utf-8"?>
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true">

      android:id="@+id/appBar"
     android:orientation="vertical"
     android:layout_width="match_parent"
     android:layout_height="250dp"
     android:fitsSystemWindows="true">

              android:id="@+id/collapsing_toolbar"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
         app:contentScrim="?attr/colorPrimary"
         app:layout_scrollFlags="scroll|exitUntilCollapsed"
         android:fitsSystemWindows="true">

                      android:id="@+id/toolbar"
             android:layout_width="match_parent"
             android:layout_height="?attr/actionBarSize"
             app:layout_collapseMode="pin"/>

                      android:id="@+id/fruit_image_view"
             android:layout_width="match_parent"
             android:layout_height="match_parent"
             android:scaleType="centerCrop"
             app:layout_collapseMode="parallax"
             android:fitsSystemWindows="true"/>
     

 

            android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="@string/appbar_scrolling_view_behavior">

                    android:orientation="vertical"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

                            android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_marginBottom="15dp"
                android:layout_marginLeft="15dp"
                android:layout_marginRight="15dp"
                android:layout_marginTop="35dp"
                app:cardCornerRadius="4dp">
                                    android:id="@+id/fruit_content_text"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_margin="10dp" />
            

        
    

            android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="16dp"
        android:src="@drawable/ic_check_circle_black_24dp"
        app:layout_anchor="@id/appBar"
        app:layout_anchorGravity="bottom|end">
    

FruitActivity代码如下：

package com.example.administrator.testtoolbar;

import android.content.Intent;
import android.os.Bundle;
import android.os.PersistableBundle;
import android.support.design.widget.CollapsingToolbarLayout;
import android.support.v7.app.ActionBar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.MenuItem;
import android.widget.ImageView;
import android.widget.TextView;

import com.bumptech.glide.Glide;

/**
 * Created by Administrator on 2018/4/17/017.
 */

public class FruitActivity extends AppCompatActivity{

    public static final String FRUIT_NAME = "fruit_name";
    public static final String FRUIT_IMAGE_ID = "fruit_image_id";

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_fruit);
        Intent intent = getIntent();
        String fruitName = intent.getStringExtra(FRUIT_NAME);
        int fruitImageId = intent.getIntExtra(FRUIT_IMAGE_ID,0);

        //初始化控件
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        CollapsingToolbarLayout collapsingToolbar = (CollapsingToolbarLayout) findViewById(R.id.collapsing_toolbar);
        ImageView fruitImageView = (ImageView) findViewById(R.id.fruit_image_view);
        TextView fruitContentText = (TextView) findViewById(R.id.fruit_content_text);
        setSupportActionBar(toolbar);
        ActionBar actionBar = getSupportActionBar();
        if(actionBar != null){
            actionBar.setDisplayHomeAsUpEnabled(true);
        }
        collapsingToolbar.setTitle(fruitName);
        Glide.with(this).load(fruitImageId).into(fruitImageView);
        String fruitContent = generateFruitContent(fruitName);
        fruitContentText.setText(fruitContent);
    }

    private String generateFruitContent(String fruitName) {
        StringBuilder fruitContent = new StringBuilder();
        for(int i = 0; i < 500; i++){
            fruitContent.append(fruitName);
        }
        return fruitContent.toString();
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()){
            case android.R.id.home:
                finish();
                return true;
        }
        return super.onOptionsItemSelected(item);
    }
}

记得修改FruitAdapter的代码才能实现RecyclerView功能具体代码如下：

 View view = LayoutInflater.from(mContext).inflate(R.layout.fruit_item,
            parent,false);

    final ViewHolder holder = new ViewHolder(view);
    holder.cardView.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            int position = holder.getAdapterPosition();
            Fruit fruit = mFruitList.get(position);
            Intent intent = new Intent(mContext,FruitActivity.class);
            intent.putExtra(FruitActivity.FRUIT_NAME,fruit.getName());
            intent.putExtra(FruitActivity.FRUIT_IMAGE_ID,fruit.getImageId());
            mContext.startActivity(intent);
        }
    });
    return holder;
}

运行程序得到下面效果。