Android之Gallery和Spinner-Android学习之旅（二十九）

Spinner简介

spinner是竖直方向展开一个列表供选择。和gallery都是继承了AbsSpinner，AbsSpinner继承了AdapterView，因此AdaptyerView的属性都可以使用。

Spinner属性

实例

package peng.liu.testview;

import android.app.Activity;
import android.os.Bundle;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.BaseExpandableListAdapter;
import android.widget.ExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.SimpleAdapter;
import android.widget.Spinner;
import android.widget.TextView;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class MainActivity extends Activity {
    private Spinner spinner02;
    private String[] names = new String[]{
            "java","python","html"
    };
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        spinner02 = (Spinner) findViewById(R.id.spinner02);
        ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1,names);
        spinner02.setAdapter(adapter);
    }
}

布局代码

<LinearLayout 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" android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin"
    tools:context=".MainActivity"
    android:orientation="vertical">
   <Spinner
       android:layout_width="fill_parentw"
       android:layout_height="wrap_content"
       android:id="@+id/spinner01"
       android:entries="@array/books"
       android:prompt="@string/book"
       />
    <Spinner
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:id="@+id/spinner02"
        android:prompt="@string/book"
        />

</LinearLayout>

Gallery简介

Gallery和Spinner都是AbsSpinner的子类，所以它和Spinner相似，但它是水平的展示，而且可以用手拖动查看。但是它在新版本已经不被推荐，代替是HorizontalScrollView和ViewPager。

Gallery属性

图片浏览器实例

package peng.liu.testview;

import android.app.Activity;
import android.content.res.TypedArray;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.Gallery;
import android.widget.ImageView;

public class MainActivity extends Activity {
    private Gallery gallery;
    private ImageView image;
    private int[] names = new int[]{
       R.drawable.ic_launcher,R.drawable.ic_launcher,R.drawable.ic_launcher,R.drawable.ic_launcher,R.drawable.ic_launcher,R.drawable.ic_launcher
    };
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        gallery = (Gallery) findViewById(R.id.gallery);
        image = (ImageView) findViewById(R.id.image);
        BaseAdapter adapter = new BaseAdapter() {
            @Override
            public int getCount() {
                return names.length;
            }

            @Override
            public Object getItem(int i) {
                return null;
            }

            @Override
            public long getItemId(int i) {
                return 0;
            }

            @Override
            public View getView(int i, View view, ViewGroup viewGroup) {
                ImageView image = new ImageView(MainActivity.this);
                image.setImageResource(names[i]);
                image.setLayoutParams(new Gallery.LayoutParams(75,100));
                image.setScaleType(ImageView.ScaleType.FIT_XY);
                return image;
            }
        };
        gallery.setAdapter(adapter);
        gallery.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> adapterView, View view, int i, long l) {
                image.setImageResource(names[i]);
            }

            @Override
            public void onNothingSelected(AdapterView<?> adapterView) {

            }
        });
    }
}

布局代码

<LinearLayout 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" android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin"
    tools:context=".MainActivity"
    android:orientation="vertical">
   <ImageView
       android:layout_width="320dp"
       android:layout_height="320dp"
       android:id="@+id/image"
       />
    <Gallery
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="25dp"
        android:unselectedAlpha="0.6"
        android:spacing="2pt"
        android:id="@+id/gallery"/>
</LinearLayout>