C#寫日記類實例。本站提示廣大學習愛好者:(C#寫日記類實例)文章只能為提供參考,不一定能成為您想要的結果。以下是C#寫日記類實例正文
5.0供給了兩個新的Widget,它們應用了Material Design 的style和animation:
它兩位於 sdk/extras/android/support/v7/cardview 和 sdk/extras/android/support/v7/RecyclerView

創立列表
RecyclerView組件是一個更先輩和靈巧的版本的列表視圖。這個小部件是一個異常有用率的容器,經由過程無限的views,可以轉動顯示年夜型數據集。
RecyclerView組件數據聚集的元素,可在運轉時依據用戶操作或收集事宜停止轉變。
RecyclerView類簡化了顯示和處置年夜型數據集,它供給了:
你可以在RecyclerView中靈巧界說 結構治理器和動畫

要應用RecyclerView組件,您必需指定一個適配器和結構治理器。創立一個適配器,繼續RecyclerView.Adapter類。有關更多信息,請拜見上面的例子。
RecyclerView並肯定重用項目視圖時,結構治理器的應用item的辦法,不再是對用戶可見。重用(或收受接管)視圖,結構治理器能夠會問適配器,調換內容為分歧的數據集的元素。收受接管view時,以這類方法來改良機能:防止創立不用要的view或履行消費年夜的findViewById()查詢。
RecyclerView供給了以下治理器:
要創立一個自界說結構治理器,須要繼續RecyclerView.LayoutManager類
動畫:
添加和刪除item的動畫,在RecyclerView默許啟用。定制這些動畫,須要繼續RecyclerView.ItemAnimator類並應用RecyclerView.setItemAnimator()辦法。
例子:
layout
<!-- A RecyclerView with some commonly used attributes --> <android.support.v7.widget.RecyclerView android:id="@+id/my_recycler_view" android:scrollbars="vertical" android:layout_width="match_parent" android:layout_height="match_parent"/>
activity
public class MyActivity extends Activity {
private RecyclerView mRecyclerView;
private RecyclerView.Adapter mAdapter;
private RecyclerView.LayoutManager mLayoutManager;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.my_activity);
mRecyclerView = (RecyclerView) findViewById(R.id.my_recycler_view);
// use this setting to improve performance if you know that changes
// in content do not change the layout size of the RecyclerView
mRecyclerView.setHasFixedSize(true); //應用固定size 以優化機能
// use a linear layout manager
mLayoutManager = new LinearLayoutManager(this);
mRecyclerView.setLayoutManager(mLayoutManager);
// specify an adapter (see also next example)
mAdapter = new MyAdapter(myDataset);
mRecyclerView.setAdapter(mAdapter);
}
...
}
adapter
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
private String[] mDataset;
// Provide a reference to the views for each data item
// Complex data items may need more than one view per item, and
// you provide access to all the views for a data item in a view holder
public static class ViewHolder extends RecyclerView.ViewHolder {
// each data item is just a string in this case
public TextView mTextView;
public ViewHolder(TextView v) {
super(v);
mTextView = v;
}
}
// Provide a suitable constructor (depends on the kind of dataset)
public MyAdapter(String[] myDataset) {
mDataset = myDataset;
}
// Create new views (invoked by the layout manager)
@Override
public MyAdapter.ViewHolder onCreateViewHolder(ViewGroup parent,
int viewType) {
// create a new view
TextView v = (TextView)LayoutInflater.from(parent.getContext())
.inflate(R.layout.my_text_view, parent, false);
// set the view's size, margins, paddings and layout parameters
...
ViewHolder vh = new ViewHolder(v);
return vh;
}
// WordStr the contents of a view (invoked by the layout manager)
@Override
public void onBindViewHolder(ViewHolder holder, int position) {
// - get element from your dataset at this position
// - replace the contents of the view with that element
holder.mTextView.setText(mDataset[position]);
}
// Return the size of your dataset (invoked by the layout manager)
@Override
public int getItemCount() {
return mDataset.length;
}
}
創立卡片
CardView繼續自FrameLayout,以卡片式顯示分歧的外不雅。它可以有暗影和圓角
創立一個有暗影的卡片,應用card_view:cardElevation屬性。
應用這些屬性來定制CardView組件的外不雅:
例
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
xmlns:card_view="http://schemas.android.com/apk/res-auto"
... >
<!-- A CardView that contains a TextView -->
<android.support.v7.widget.CardView
xmlns:card_view="http://schemas.android.com/apk/res-auto"
android:id="@+id/card_view"
android:layout_gravity="center"
android:layout_width="200dp"
android:layout_height="200dp"
card_view:cardCornerRadius="4dp">
<TextView
android:id="@+id/info_text"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</android.support.v7.widget.CardView>
</LinearLayout>
添加依附:
gradle依附
dependencies {
...
compile 'com.android.support:cardview-v7:21.0.+'
compile 'com.android.support:recyclerview-v7:21.0.+'
}