Android实战简单新闻客户端(5)---其他细节优化，更符合MD设计

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使用cardview使listview的item看起来立体:

详情阅读文章:CardView的使用
listview item.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView 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="wrap_content"
    android:layout_marginBottom="5dp"
    android:layout_marginLeft="5dp"
    android:layout_marginRight="5dp"
    android:foreground="?attr/selectableItemBackground">

    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:gravity="center">

        <com.android.volley.toolbox.NetworkImageView
            android:id="@+id/news_pic"
            android:layout_width="100dp"
            android:layout_height="100dp"
            android:scaleType="fitCenter"
            android:src="@mipmap/ic_launcher" />

        <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="match_parent"
            android:layout_weight="1"
            android:gravity="center"
            android:orientation="vertical">

            <TextView
                android:id="@+id/text_title"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:gravity="center"
                android:text="xxxxxx"
                android:textSize="20sp" />

            <TextView
                android:id="@+id/text_content"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_weight="1"
                android:gravity="center"
                android:text="xxxxxx"
                android:textColor="#cc0000"
                android:textSize="15sp" />
        </LinearLayout>
    </LinearLayout>
</android.support.v7.widget.CardView>

注意这个是用来设置点击阴影的

android:foreground="?attr/selectableItemBackground"

带图片伸缩的ToolBar–CollapsingToolbarLayout+AppBarLayout+CoordinatorLayout

参考文章:Android5.0+(CollapsingToolbarLayout)

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".Activity.MainActivity">

    <android.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="256dp"
        android:fitsSystemWindows="true"
        android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

        <android.support.design.widget.CollapsingToolbarLayout
            android:id="@+id/collapsing_toolbar"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:fitsSystemWindows="true"
            app:contentScrim="?attr/colorPrimary"
            app:expandedTitleMarginEnd="64dp"
            app:expandedTitleMarginStart="48dp"
            app:layout_scrollFlags="scroll|exitUntilCollapsed">

            <ImageView
                android:id="@+id/ivImage"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:fitsSystemWindows="true"
                android:scaleType="centerCrop"
                android:src="@mipmap/ic_launcher"
                android:transitionName="新闻图片"
                app:layout_collapseMode="parallax"
                app:layout_collapseParallaxMultiplier="0.7" />

            <android.support.v7.widget.Toolbar
                android:id="@+id/toolbar"
                android:layout_width="match_parent"
                android:layout_height="?attr/actionBarSize"
                app:layout_collapseMode="pin"
                app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />
        </android.support.design.widget.CollapsingToolbarLayout>
    </android.support.design.widget.AppBarLayout>

    <android.support.v4.widget.NestedScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:fillViewport="true"
        android:fitsSystemWindows="true"
        app:layout_behavior="@string/appbar_scrolling_view_behavior">

        <WebView
            android:id="@+id/web_text"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"></WebView>
    </android.support.v4.widget.NestedScrollView>
</android.support.design.widget.CoordinatorLayout>

说明:webview必须使用NestedScrollView包裹才能实现效果。
测试:

主activity的toolbar修改:

toolbar.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.AppBarLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:id="@+id/appbar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

    <android.support.v7.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        android:background="?attr/colorPrimary"
        app:layout_scrollFlags="scroll|enterAlways"
        android:elevation="5dp"
        app:popupTheme="@style/ThemeOverlay.AppCompat.Light" />
</android.support.design.widget.AppBarLayout>

main_activity.xml

<android.support.design.widget.CoordinatorLayout
        android:id="@+id/main_content"
        android:layout_width="match_parent"
        android:layout_height="match_parent">
        <include
            android:id="@+id/appbar"
            layout="@layout/toolbar" />


        <FrameLayout
            android:id="@+id/frame_content"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_below="@+id/appbar"
            android:scrollbars="none"
            android:elevation="5dp"
            app:layout_behavior="@string/appbar_scrolling_view_behavior" />

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

最关键的一点:
由于使用的是listview没有实现NestedScrollingChild接口
，效果不能实现。
解决办法：1.使用RecyclerView代替listview
2.引入NestedScrollView
3.重写listview 实现NestedScrollingChild接口

参考文章:http://blog.csdn.net/qq_33689414/article/details/51362082

<android.support.v4.widget.NestedScrollView
        android:fillViewport="true"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="@string/appbar_scrolling_view_behavior">

    <ListView
        android:id="@+id/listview_news"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"></ListView>
    </android.support.v4.widget.NestedScrollView>

失败出现滑动冲突，listview显示不全。重写去除listview滚动事件。

参考文章:http://blog.csdn.net/mitos_yggdrasill/article/details/51918546

public class NestedListView extends ListView {

    public NestedListView(Context context) {
        super(context);
    }

    public NestedListView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        int expandSpec = MeasureSpec.makeMeasureSpec(Integer.MAX_VALUE >> 2, MeasureSpec.AT_MOST);
        super.onMeasure(widthMeasureSpec, expandSpec);
    }
}  

使用自定义的listview代替原来的lisview。

<?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"
    xmlns:app="http://schemas.android.com/apk/res-auto">


    <android.support.v4.widget.NestedScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:fillViewport="true"
        app:layout_behavior="@string/appbar_scrolling_view_behavior">

    <com.example.administrator.newsbyhuluwo.Activity.NestedListView
        android:id="@+id/listview_news"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

    </com.example.administrator.newsbyhuluwo.Activity.NestedListView>
    </android.support.v4.widget.NestedScrollView>
</LinearLayout>

NewsListFragment.java

public class NewsListFragment extends Fragment {

    public static List<News> newsList = new ArrayList<>();
    private NestedListView listView;
    public static NewAdapter newAdapter;

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
    }

    @Nullable
    @Override
    public View onCreateView(final LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_newslist, container, false);
        listView = (NestedListView) view.findViewById(R.id.listview_news);
        newAdapter = new NewAdapter(getActivity(), R.layout.item_newslist, newsList);
        listView.setAdapter(newAdapter);
        listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                Toast.makeText(getContext(),
                        newsList.get(position).getUrl(), Toast.LENGTH_LONG).show();

                Context context = getActivity();

                Intent intent = new Intent(context, NewsDetailActivity.class);

                //用Bundle携带数据
                Bundle bundle=new Bundle();
                //传递name参数为tinyphp
                bundle.putString("uri", newsList.get(position).getUrl());
                intent.putExtras(bundle);
                context.startActivity(intent);
            }
        });
        return view;
    }
}

测试: