Android巧用ActionBar实现下拉式导航

本文实例为大家分享了ActionBar下拉式导航的实现代码，供大家参考，具体内容如下

利用Actionbar同样可以很轻松的实现下拉式的导航方式，若想实现这种效果：

1）actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_LIST) 

2)setListNavigationCallbacks(SpinnerAdapter adapter,ActionBar.OnNavigationListener callback).

首先是创建一个Fragment类：

package ccom.app.main;

import android.annotation.SuppressLint;
import android.app.Fragment;
import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewGroup.LayoutParams;
import android.widget.TextView;

@SuppressLint("NewApi")
public class MyFragment extends Fragment {

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

Context context = this.getActivity();

TextView tv = new TextView(context);

Bundle arc = this.getArguments();

int tabs=arc.getInt("key");

tv.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,
   LayoutParams.WRAP_CONTENT));

tv.setText("hello actionbar "+tabs);

return tv;

}

}

main.xml:

<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=".Main" >

<LinearLayout
 android:id="@+id/content"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:orientation="vertical" />

</RelativeLayout>

自定义的用于显示textview的mytextview.xml:

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/text1"
android:textColor="#fff"
android:background="#696969"
android:layout_width="60sp"
android:layout_height="match_parent"
android:textAppearance="?android:attr/textAppearanceListItemSmall"
android:gravity="center_vertical"
android:paddingStart="?android:attr/listPreferredItemPaddingStart"
android:minHeight="?android:attr/listPreferredItemHeightSmall"
/>

Main.java

package ccom.app.main;

import android.annotation.SuppressLint;
import android.app.ActionBar;
import android.app.Activity;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.widget.ArrayAdapter;

@SuppressLint("NewApi")
public class Main extends Activity implements ActionBar.OnNavigationListener {

ActionBar actionBar = null;

@Override
protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.main);

actionBar = this.getActionBar();

actionBar.setDisplayShowTitleEnabled(true);

actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_LIST);

actionBar.setListNavigationCallbacks(new ArrayAdapter(Main.this,
   R.layout.mytextview, R.id.text1, new String[] { "tab1", "tab2",
     "tab3" }), this);

}

@Override
public boolean onNavigationItemSelected(int itemPosition, long itemId) {

MyFragment mf = new MyFragment();
 Bundle bundle = new Bundle();
 bundle.putInt("key", itemPosition + 1);
 mf.setArguments(bundle);

FragmentTransaction action = this.getFragmentManager()
   .beginTransaction();
 action.replace(R.id.content, mf);
 action.commit();
 return true;
}

}

实现的效果如图：