记录每天所学的东西，也当作笔记

1.Material Design ToolBar的使用

首先，在values创建colors.xml中定义三个颜色，colorPrimary,colorPrimary,colorAccent具体显示效果

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <color name="colorPrimary">#795548</color>
    <color name="colorPrimaryDark">#5D4037</color>
    <color name="colorAccent">#ffeb3b</color>
</resources>

接下来在style中应用该颜色

<resources>

    <!-- Base application theme. -->
    <style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">
        <!-- Customize your theme here. -->
        <item name="colorPrimary">@color/colorPrimary</item>
        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
        <item name="colorAccent">@color/colorAccent</item>
    </style>
    
</resources>

<android.support.v7.widget.Toolbar xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/tool_bar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:minHeight="?attr/actionBarSize"
    android:background="?attr/colorPrimary"
    app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
    app:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar" />

minHeight采用系统的actionbar的高度

背景色是采用主题中的colorPrimary就是一开始定义的，这里的 ?attr/colorPrimary 根据你的Activity的theme而定，如果没有定义，则看app的theme

popupTheme指的是弹出菜单的主题

然后将该toolbar添加到activity_layout.xml中去

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <include
        layout="@layout/toolbar" />

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_marginTop="?attr/actionBarSize">
    </RelativeLayout>


</RelativeLayout>

最后，只要在MainActivity中把toolbar用上即可，声明

private Toolbar toolbar;

在oncreate()中使用toolbar

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

2.返回导航栏的使用

getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setDisplayShowHomeEnabled(true);<span style="color:#cc7832">
</span>

getSupportActionBar() 这里返回的是Toolbar

然后再处理按钮事件

@Override
    public boolean onOptionsItemSelected(MenuItem item) {

        switch (item.getItemId()){
            case R.id.home:
                NavUtils.navigateUpFromSameTask(this);
                return true;
        }
        return super.onOptionsItemSelected(item);
    }

<meta-data android:name="android.support.PARENT_ACTIVITY"
           android:value=".MainActivity"/>

3.RecyclerView的使用

compile 'com.android.support:recyclerview-v7:22.2.1'

布局文件中添加组件

<android.support.v7.widget.RecyclerView
        android:id="@+id/my_recycler"
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>

然后在java代码中初始化必须的组件

    private RecyclerView recyclerView;
    private List<String> datas;
    private MyAdapter adaper;
    private int[] res = {
            R.drawable.img_1,
            R.drawable.img_2,
            R.drawable.img_3,
            R.drawable.img_4,
            R.drawable.img_5
    };

class MyAdapter extends RecyclerView.Adapter<MyViewHolder> {
        LayoutInflater inflater;
        Context context;
        List<String> data;

        public MyAdapter(Context c, List<String> list) {
            context = c;
            data = list;
            inflater = LayoutInflater.from(c);
        }

        @Override
        public MyViewHolder onCreateViewHolder(ViewGroup parent, int position) {
            View view = inflater.inflate(R.layout.text_layout, parent, false);
            view.setOnClickListener(new MyOnClickListener());
            MyViewHolder holder = new MyViewHolder(view);

            return holder;
        }

        @Override
        public void onBindViewHolder(MyViewHolder holder, int i) {
            holder.tv.setText(data.get(i));
            holder.iv.setImageResource(res[i % 5]);

        }

        @Override
        public int getItemCount() {
            return data.size();
        }
    }

class MyViewHolder extends RecyclerView.ViewHolder {
        TextView tv;
        ImageView iv;

        public MyViewHolder(View itemView) {
            super(itemView);
            tv = (TextView) itemView.findViewById(R.id.my_text);
            iv = (ImageView) itemView.findViewById(R.id.my_img);
        }
        
    }

最后在onCreate()方法中使用

        adaper = new MyAdapter(this, datas);
        recyclerView.setAdapter(adaper);
        recyclerView.setLayoutManager(new LinearLayoutManager(this, LinearLayoutManager.VERTICAL, false));

完成

4.Quick Return Pattern

主要修改在于布局

compile 'com.android.support:design:22.2.1'

<android.support.design.widget.CoordinatorLayout 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.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <android.support.v7.widget.Toolbar
            android:id="@+id/tool_bar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:layout_scrollFlags="scroll|enterAlways"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Light"
            app:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar" />


    </android.support.design.widget.AppBarLayout>


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


</android.support.design.widget.CoordinatorLayout>

app:layout_scrollFlags="scroll|enterAlways"

app:layout_behavior="@string/appbar_scrolling_view_behavior"