Question

我有6张可绘图像。我把这些图像放在一个2x3的GridView中，如果它是portraite，如果它是横向的，则放置3x2，但我有一个问题：如果我尝试根据parent.getMeasuredWidth（）和parent.getMeasuredHeight（）;

进行测量

第一个drawable总是0作为宽度和高度;

来自日志：

w：0 h：0

代码 ImageAdapter ：

public class ImageAdapter extends BaseAdapter {
    private Context mContext;    
    public ImageAdapter(Context c) {mContext = c;}    
    public int getCount() {return mThumbIds.length;}    
    public Object getItem(int position) {return null;}    
    public long getItemId(int position) {return 0;}
    public View getView(int position, View convertView, final ViewGroup parent) {
        ImageView imageView;
        if (convertView == null) {
            int width  = parent.getMeasuredWidth();
            int height = parent.getMeasuredHeight();
            int orientation = parent.getResources().getConfiguration().orientation;
            int vh,vo;
            if(orientation == 1){
                 vh = width/2;
                 vo = height/3;
            } else {
                 vh = (width/3);
                 vo = (height/2);
            }
            Log.e(TAG,"w: "+vh+" h:"+vo);
            imageView = new ImageView(mContext);
            imageView.setLayoutParams(new GridView.LayoutParams(vh, vo));
            imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
            imageView.setPadding(0, 0, 0, 0);
        } else {
            imageView = (ImageView) convertView;
        }    

        imageView.setImageResource(mThumbIds[position]);

        return imageView;
    }

    // references to our images
    private Integer[] mThumbIds = {
            R.drawable.gradient_bg_t1,
            R.drawable.gradient_bg_t2,
            R.drawable.gradient_bg_t4,
            R.drawable.gradient_bg_t5,
            R.drawable.gradient_bg_t6,
            R.drawable.gradient_bg_t3
    };
}

代码 MainActivity

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.my_layout);

    gridview = (GridView) findViewById(R.id.gridview);
    gridview.setAdapter(new ImageAdapter(this));
    gridview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        public void onItemClick(AdapterView<?> parent, View v,
                                int position, long id) {

        }
    });
}

谢谢。

Answer 1

它返回零，因为父视图尚未绘制。您可以将代码发布到父视图，以便在绘制父视图后运行。

使用以下代码：

parent.post(new Runnable() {
@Override
public void run() {
    int w = parent.getMeasuredWidth();
    int h = parent.getMeasuredHeight();

    ...
}
});

Answer 2

我已经在ImageAdapter中尝试过@Amir Ziarati的代码（在StackOverflow中找到它），但我无法将值超出范围。

我喝了一点咖啡后，我改变了代码：我在ImageAdapter 2中创建了新的int变量 w，h 的宽度和高度：

private Context mContext;
    private int w,h;

    public ImageAdapter(Context c,int width,int height) {
        mContext = c;
        w = width;
        h = height;
    }

并在MainActivity中：

    gridview = (GridView) findViewById(R.id.gridview);
    gridview.post(new Runnable() {
        @Override
        public void run() {
            int w = gridview.getMeasuredWidth();
            int h = gridview.getMeasuredHeight();
            gridview.setAdapter(new ImageAdapter(MainActivity.this,w,h));
        }
    });

    gridview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        public void onItemClick(AdapterView<?> parent, View v,
                                int position, long id) {
        }
    });

它正在发挥作用。

parent.getMeasuredWidth（）和parent.getMeasuredHeight（）在ImageAdapter for GridView中返回0

第一个drawable总是0作为宽度和高度;

w：0 h：0

2 个答案: