一.ImageSwitcher(图片切换器):
当我们想点击一张图片时,想让它出现的不太突然,想要缓慢显示,这时Gallery视图就需要ImageSwitcher来配合使用。
其中我们还需要用到ViewFactory接口,这是一个视图转换器,我们要重写makeView()方法,来创建一个用于添加到视图转换器(ViewSwitcher)中的新视图。
动画效果:
由左向右滑入的效果:
android.R.anim.slide_in_left
android.R.anim.slide_out_right
淡入淡出:
android.R.anim.fade_in
android.R.anim.fade_out
演示实例:
布局文件:
<?xml version="1.0" encoding="utf-8" ?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/textView1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="显示图片:" />
<Gallery
android:id="@+id/gallery1"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<ImageSwitcher
android:id="@+id/imageSwitcher1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
/>
</LinearLayout>
自定义属性(attrs.xml):
<?xml version="1.0" encoding="utf-8"?>
<resources>
<declare-styleable name="Gallery1">
<attr name="android:galleryItemBackground"/>
</declare-styleable>
</resources>
主要代码:
public class MainActivity extends Activity implements ViewFactory {
Integer[] imgId = {R.drawable.img1,
R.drawable.img2,R.drawable.img3,
R.drawable.img4,R.drawable.img5,
R.drawable.img8,R.drawable.img9,};
private ImageSwitcher is ;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
is = (ImageSwitcher)findViewById(R.id.imageSwitcher1);
is.setFactory(this);
//设置动画效果。由左向右滑入
is.setInAnimation(AnimationUtils.loadAnimation(this, android.R.anim.slide_in_left));
is.setOutAnimation(AnimationUtils.loadAnimation(this, android.R.anim.slide_out_right));
Gallery gallery = (Gallery)findViewById(R.id.gallery1);
gallery.setAdapter(new ImageAdapter(this));
gallery.setOnItemClickListener(new OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
is.setImageResource(imgId[arg2]);
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
//创建一个新的View来添加到ImageView中。
@Override
public View makeView() {
ImageView imageView = new ImageView(this);
//设置背景颜色
imageView.setBackgroundColor(0xffffff00);
imageView.setScaleType(ImageView.ScaleType.FIT_CENTER);
//填充控件。
imageView.setLayoutParams(new ImageSwitcher.LayoutParams(LayoutParams.FILL_PARENT,
LayoutParams.FILL_PARENT));
return imageView;
}
//Image适配器类,绑定Gallery。
private class ImageAdapter extends BaseAdapter{
private Context context;
private int item;
public ImageAdapter(Context context) {
this.context = context;
TypedArray ta = context.obtainStyledAttributes(R.styleable.Gallery1);
item = ta.getResourceId(R.styleable.Gallery1_android_galleryItemBackground, 0);
ta.recycle();
}
@Override
public int getCount() {
return imgId.length;
}
@Override
public Object getItem(int arg0) {
// TODO Auto-generated method stub
return arg0;
}
@Override
public long getItemId(int arg0) {
// TODO Auto-generated method stub
return arg0;
}
@Override
public View getView(int arg0, View arg1, ViewGroup arg2) {
// TODO Auto-generated method stub
ImageView image = new ImageView(context);
image.setImageResource(imgId[arg0]);
image.setScaleType(ImageView.ScaleType.FIT_XY);
image.setLayoutParams(new Gallery.LayoutParams(160,130));
image.setBackgroundResource(item);
return image;
}
}
}
运行图片:
当我们点击第二章图片时:
当点击后面图片时: