具體步奏:
1、建立新項目ActivityBasicActivity
2、把圖片拷貝到res/drawable目錄
3、在res/values目錄中新建一個attrs.xml內容
這裏我是用Framelayout來實現疊加效果,使用ImageView來顯示大圖,Gallery來展示畫廊,Toast類時用來顯示圖像名稱
main.xml代碼:
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/frameLayout1"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<ImageView
android:id="@+id/imageView1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:src="@drawable/p1"
/>
<Gallery
android:id="@+id/gallery1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:spacing="5dp"/>
</FrameLayout>
attrs.xml代碼:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<declare-styleable name="Gallery1">
<attr name="android:galleryItemBackground"></attr>
</declare-styleable>
</resources>
這部
Java代碼:
package com.demo;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Gallery;
import android.widget.Toast;
import android.widget.ImageView;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.content.Context;
import android.content.res.TypedArray;
public class ActivityBasicActivity extends Activity {
///要顯示的圖像,圖片數組
Integer[] images = {
R.drawable.p1,
R.drawable.p2,
R.drawable.p3,
R.drawable.p4,
R.drawable.p5
};
/** 當第一次被創建時調用 */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);//創建一個線性佈局管理器
setContentView(R.layout.main); //顯示該視圖
///定義UI組件
///final 如果修飾類,該類不能被繼承;如果修飾變量,該變量不能被改變,就是不能再重新賦值;
///如果修飾方法,這個方法不能被重寫。
final ImageView iv = (ImageView)findViewById(R.id.imageView1);
Gallery gallery = (Gallery) findViewById(R.id.gallery1);///獲取id傳值給gallery
///設置圖片匹配器
gallery.setAdapter(new ImageAdapter(this));
///設置AdapterView點擊監聽器,Gallery是AdapterView的子類
gallery.setOnItemClickListener(new OnItemClickListener(){
public void onItemClick(AdapterView<?> parent, View v, int position, long id)
{
///顯示點擊的是第幾張圖片
Toast.makeText(getBaseContext(), "第"+(position+1)+"張", Toast.LENGTH_SHORT).show();
///設置背景部分的ImageView顯示當前的Item的圖片
iv.setImageResource(((ImageView)v).getId());
//iv.setImageResource(images[position]);
}
});
}
public class ImageAdapter extends BaseAdapter{
///Item的修飾背景
int myGalleryItemBackground;
///上下文對象
private Context myContext;
///構造方法
public ImageAdapter(Context c){
myContext = c;
////讀取styleable資源,設定樣式
TypedArray a = obtainStyledAttributes(R.styleable.Gallery1);
myGalleryItemBackground = a.getResourceId(R.styleable.Gallery1_android_galleryItemBackground, 0);
a.recycle();
}
///返回相片數組的數量
public int getCount(){
return images.length;
}
///返回項目
public Object getItem(int position){
return position;
}
///返回項目id
public long getItemId(int position){
return position;
}
///返回視圖
public View getView(int position, View convertView, ViewGroup parent){
ImageView iv = new ImageView(myContext);
iv.setImageResource(images[position]);
//給生成的ImageView設置id,不設置的話id都是-1
iv.setId(images[position]);
iv.setLayoutParams(new Gallery.LayoutParams(120,160));
iv.setScaleType(ImageView.ScaleType.FIT_XY);
iv.setBackgroundResource(myGalleryItemBackground);
return iv;
}
}
}
這裏提供一個小擴展,AdapterView的繼承關係