自我认识:Gallery就是我们手机中经常用的相册的意思,用这个空间可以通过左右滑动显示图片
首先附上学习Gallery时候的目录列表,下面会详细附上各部分的代码
运行结果如下图:
下面是详细的代码部分,还是按照布局文件-Java代码-manifests这个顺序
activity_main.xml代码
说明:这里面仍用的是自己创建项目 时候的相对布局,里面只有一个Gallery控件
<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" 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">
<Gallery
android:id="@+id/gallery_id"
android:layout_width="match_parent"
android:layout_height="100dp"
android:unselectedAlpha="0.5"
android:spacing="20dp"
android:gravity="center_horizontal"
></Gallery>
</RelativeLayout>
grideviewtest.xml代码
说明:线性布局嵌套线性布局,里面的线性布局里面放一个ImageView和TextView。。。主体线性布局有一个10dp的padding.
<?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"
android:padding="10dp"
android:orientation="vertical" >
<LinearLayout
android:id="@+id/linearlayout_id"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
>
<ImageView
android:id="@+id/image_grideview"
android:layout_width="80dp"
android:layout_height="80dp"
/>
<TextView
android:id="@+id/text_fruitname"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="水果名字"
android:layout_gravity="center_horizontal"
/>
</LinearLayout>
</LinearLayout>
MyGalleryViewAdapter.java中的代码
说明:MyGalleryViewAdapter仍然是继承自BaseAdaper,这里使用的都是效率最高的、最节约内存的ViewHolder
package com.example.administrator.mygallery.adapter;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;
import com.example.administrator.mygallery.R;
import com.example.administrator.mygallery.model.Fruit;
import java.util.List;
public class MyGalleryViewAdapter extends BaseAdapter{
private List<Fruit> mFruit;
private LayoutInflater inflater;
public MyGalleryViewAdapter(List<Fruit> mFruit, LayoutInflater inflater)
{
this.mFruit=mFruit;
this.inflater=inflater;
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return mFruit.size();
}
@Override
public Object getItem(int position) {
return position;
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder viewHolder=null;
if(convertView==null)
{
convertView=inflater.inflate(R.layout.grideviewtest, null);
viewHolder=new ViewHolder();
viewHolder.imageView = (ImageView) convertView.findViewById(R.id.image_grideview);
viewHolder.textView=(TextView) convertView.findViewById(R.id.text_fruitname);
convertView.setTag(viewHolder);
}else
{
viewHolder=(ViewHolder)convertView.getTag();
}
Fruit fruit=mFruit.get(position);
viewHolder.imageView.setImageResource(fruit.getImg());
viewHolder.textView.setText(fruit.getName());
return convertView;
}
class ViewHolder
{
ImageView imageView;
TextView textView;
}
}
Fruit.java中的代码:
说明:就是一个简单的类,里面有两个属性,添加上get和set方法,还有构造方法
package com.example.administrator.mygallery.model;
public class Fruit {
private String name;
private int img;
public Fruit(String name, int img)
{
this.name = name;
this.img = img;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getImg() {
return img;
}
public void setImg(int img) {
this.img = img;
}
}
MainActivity中的代码。。这是项目最重要的代码部分
说明:私有化本类中用到的属性,利用MyGalleryViewAdapter.java的构造方法生成一个adapter。
package com.example.administrator.mygallery;
import android.app.Activity;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Gallery;
import android.widget.GridView;
import com.example.administrator.mygallery.adapter.MyGalleryViewAdapter;
import com.example.administrator.mygallery.model.Fruit;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends Activity {
private Gallery gallery;
private List<Fruit> mFruit;
private LayoutInflater inflater;
private MyGalleryViewAdapter adapter;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
gallery=(Gallery) findViewById(R.id.gallery_id);
inflater=getLayoutInflater();
ininFruit();
adapter=new MyGalleryViewAdapter(mFruit, inflater);
gallery.setAdapter(adapter);
}
public List<Fruit> ininFruit()
{
mFruit = new ArrayList<Fruit>();
for (int i = 0; i < 5; i++) {
Fruit fish = new Fruit("鱼", R.mipmap.fish);
Fruit jellyfish = new Fruit("jelly鱼", R.mipmap.jelly_fish);
Fruit kbugbuster = new Fruit("kbugbuster", R.mipmap.kbugbuster);
Fruit penguin = new Fruit("penguin", R.mipmap.penguin);
Fruit pig = new Fruit("penguin", R.mipmap.penguin);
Fruit poweranimal = new Fruit("poweranimal", R.mipmap.power_animal);
mFruit.add(fish);
mFruit.add(jellyfish);
mFruit.add(kbugbuster);
mFruit.add(penguin);
mFruit.add(pig);
mFruit.add(poweranimal);
}
return mFruit;
}
}
AndroidManifest.xml代码如下:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.administrator.mygallery" >
<application
android:allowBackup="true"
android:icon="@mipmap/album"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
总结:
学习Gallery控件,没有什么难的,就是生成一个adapter,这个才是项目的难点。
说明:
项目中用到的图片在这里就不添加了。