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我想显示水平图像滚动列表，所以我在谷歌上搜索，发现非常好的教程，但没有一个解释为该水平列表实现动态容器的想法。

我想在水平列表的开头显示一个图像，在列表的末尾显示一个图像。（如箭头图像）并且我想为我的图像滚动列表设置图像容器，它非常令人困惑，而且像我一样特别新鲜。我被困在这一点上，以解释我到底想要什么，我附上了一张图片和我当前的代码。

任何帮助表示赞赏。请指导我。感谢您宝贵的时间。

这是主要活动代码

MyHorizontalLayout myHorizontalLayout;
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    myHorizontalLayout = (MyHorizontalLayout)findViewById(R.id.mygallery);
    String ExternalStorageDirectoryPath = Environment
            .getExternalStorageDirectory()
            .getAbsolutePath();
    String targetPath = ExternalStorageDirectoryPath + "/test/";
    Toast.makeText(getApplicationContext(), targetPath, Toast.LENGTH_LONG).show();
    File targetDirector = new File(targetPath);
     File[] files = targetDirector.listFiles();
    for (File file : files){
    myHorizontalLayout.add(file.getAbsolutePath());
    }    
}

这是我的 Horizo​​ntalLayout 代码

public class MyHorizontalLayout extends LinearLayout {
Context myContext;
ArrayList<String> itemList = new ArrayList<String>();
public MyHorizontalLayout(Context context) {
    super(context);
    myContext = context;
}
public MyHorizontalLayout(Context context, AttributeSet attrs) {
    super(context, attrs);
    myContext = context;
}
public MyHorizontalLayout(Context context, AttributeSet attrs,
        int defStyle) {
    super(context, attrs, defStyle);
    myContext = context;
}
void add(String path){
    int newIdx = itemList.size();
    itemList.add(path);
    addView(getImageView(newIdx));  
}
ImageView getImageView(final int i){
    ImageView imageView = new ImageView(myContext);
    imageView.setLayoutParams(new LayoutParams(150, 150));
    imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
    Bitmap bm = null;
    if (i < itemList.size()){
        bm = decodeSampledBitmapFromUri(itemList.get(i), 150, 150);
    }
    imageView.setImageBitmap(bm);
    imageView.setOnClickListener(new OnClickListener(){
        @Override
        public void onClick(View v) {
            Toast.makeText(myContext, 
                    "Clicked - " + itemList.get(i), 
                    Toast.LENGTH_LONG).show();
        }});

    return imageView;
}
public Bitmap decodeSampledBitmapFromUri(String path, int reqWidth, int reqHeight) {
    Bitmap bm = null;
    // First decode with inJustDecodeBounds=true to check dimensions
    final BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeFile(path, options);
    // Calculate inSampleSize
    options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
    // Decode bitmap with inSampleSize set
    options.inJustDecodeBounds = false;
    bm = BitmapFactory.decodeFile(path, options); 
    return bm;  
}
public int calculateInSampleSize(
    BitmapFactory.Options options, int reqWidth, int reqHeight) {
    // Raw height and width of image
    final int height = options.outHeight;
    final int width = options.outWidth;
    int inSampleSize = 1;
    if (height > reqHeight || width > reqWidth) {
        if (width > height) {
            inSampleSize = Math.round((float)height / (float)reqHeight);    
        } else {
            inSampleSize = Math.round((float)width / (float)reqWidth);      
        }   
    }
    return inSampleSize;    
}

这是XML文件

<HorizontalScrollView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_marginTop="200dp" >
    <com.example.test.MyHorizontalLayout
        android:id="@+id/mygallery"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal" />

水平列表

4

1 回答 1

0

使用相对布局作为基础放置背景（滚动视图背景），在其中添加您的水平布局和使用框架布局的两个箭头。祝你好运！

于 2013-04-16T12:36:31.590 回答