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動態輸入時間和日期，相關監聽器

知識要點及注意事項

Android布局優化之<merge>標簽使用詳解

Android抽象布局——include、merge、ViewStub

Android布局優化之include與merge

2、減少視圖層級<merge />

? ? <merge/>標簽在UI的結構優化中起著非常重要的作用，它可以刪減多余的層級，優化UI。<merge/>多用于替換FrameLayout或者當一個布局包含另一個時，<merge/>標簽消除視圖層次結構中多余的視圖組。例如你的主布局文件是垂直布局，引入了一個垂直布局的include，這是如果include布局使用的LinearLayout就沒意義了，使用的話反而減慢你的UI表現。這時可以使用<merge/>標簽優化。

<merge?xmlns:android="http://schemas.android.com/apk/res/android">??
??
????<Button??
????????android:layout_width="fill_parent"???
????????android:layout_height="wrap_content"??
????????android:text="@string/add"/>??
??
????<Button??
????????android:layout_width="fill_parent"???
????????android:layout_height="wrap_content"??
????????android:text="@string/delete"/>??
??
</merge>

現在，當你添加該布局文件時(使用<include />標簽)，系統忽略<merge />節點并且直接添加兩個Button。

監聽器是程序和用戶/系統之間的橋梁

適配器是數據和視圖之間的橋梁

intent（意圖）是Android各組件（activity）之間通訊的橋梁

SimpleAdapter()的五個參數內容

靜態Activity->Fragment

Main4Activity.java

FragmentManager?fragmentManager?=?getFragmentManager();
Fragment?fragmentById?=?fragmentManager.findFragmentById(R.id.frag);
MyFragment?frag?=?(MyFragment)?fragmentById;
frag.setAaa("fragment靜態傳值");

MyFragment.java

public?class?MyFragment?extends?Fragment?{

????private?String?aaa;

????public?void?setAaa(String?aaa)?{
????????this.aaa?=?aaa;
????}

????public?String?getAaa()?{
????????return?aaa;
????}

????@Nullable
????@Override
????public?View?onCreateView(LayoutInflater?inflater,?@Nullable?ViewGroup?container,?Bundle?savedInstanceState)?{
????????//layout布局文件轉換成View對象
????????/**
?????????*?resource:Fragment需要加載的布局文件
?????????*?root：加載layout的父ViewGroup
?????????*?attachToRoot:false，不返回父ViewGroup
?????????*/
????????View?view?=?inflater.inflate(R.layout.fragment,?container,?false);
????????TextView?text?=?(TextView)?view.findViewById(R.id.text);
????????text.setText("靜態加載Fragment");
????????Button?button?=?(Button)?view.findViewById(R.id.button);
????????button.setText("獲取內容");
????????button.setOnClickListener(new?View.OnClickListener()?{
????????????@Override
????????????public?void?onClick(View?v)?{
????????????????String?value?=?getAaa();
????????????????Toast.makeText(getActivity(),?"value="+value,?Toast.LENGTH_SHORT).show();
????????????}
????????});
????????return?view;
????}
}

private?String?code?=?"Thank?you,?Activity!";

public?MyListener?listener;

public?interface?MyListener?{
????public?void?thank(String?code);
}

@Override
public?void?onAttach(Activity?activity)?{
????listener?=?(MyListener)?activity;
????super.onAttach(activity);
}

Toast.makeText(getActivity(),?"向Activity發送"+code,?Toast.LENGTH_SHORT).show();

listener.thank(code);

Main4Activity.java

@Override
public?void?thank(String?code)?{
????Toast.makeText(this,?"已成功接收到"+code+"，客氣了！",?Toast.LENGTH_SHORT).show();
}

Main4Activity.java

send.setOnClickListener(new?View.OnClickListener()?{
????@Override
????public?void?onClick(View?v)?{
????????String?text?=?editText.getText().toString();
????????MyFragment5?fragment5?=?new?MyFragment5();
????????Bundle?bundle?=?new?Bundle();
????????bundle.putString("name",text);
????????fragment5.setArguments(bundle);
????????FragmentManager?fragmentManager?=?getFragmentManager();
????????FragmentTransaction?beginTransaction?=?fragmentManager.beginTransaction();
????????beginTransaction.add(R.id.layout,fragment5,"fragment5");
????????beginTransaction.commit();
????????Toast.makeText(Main4Activity.this,?"向Fragment發送數據"+text,?Toast.LENGTH_SHORT).show();
????}
});

Fragment5.java

@Override
public?View?onCreateView(LayoutInflater?inflater,?@Nullable?ViewGroup?container,?Bundle?savedInstanceState)?{

????View?view?=?inflater.inflate(R.layout.fragment2,?container,?false);
????TextView?tv?=?(TextView)?view.findViewById(R.id.text);
????String?text?=?getArguments().get("name")?+?"";
????tv.setText(text);
????Toast.makeText(getActivity(),?"已成功接收到"+text,?Toast.LENGTH_SHORT).show();
????return?view;
}

使用arrayadapter加載listview

Android常用布局

LinearLayout(線性布局)-->線性的 垂直的 水平的 RelativeLayout(相對布局)-->最靈活的 FrameLayout(幀布局)-->布局疊加時使用 TableLayout(表格布局)-->使用GridView代替 AbsoluteLayout(絕對布局)-->極少使用

android manifest全局配置（包名和版本信息）

Uri uri = Uri.parse(url);

Intent intent = new Intent(Intent.ACTION_VIEW, uri);

startActivity(intent);

訪問網站鏈接

靜態導入 ViewFlipper 和java動態導入