如何从 sd 卡而不是可绘制的数组中添加图像

Question

我正在开发一个图像 GridView 应用程序，在该应用程序中我从可绘制数组中添加图像，但现在我想从 sd 卡中添加数组中的图像。

注意：我想添加来自特定文件夹的图像，例如："sdcard/android/data/com.example.images"

GridView 类

package com.example.androidhive;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.GridView;

public class AndroidGridLayoutActivity extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.grid_layout);

        GridView gridView = (GridView) findViewById(R.id.grid_view);

        // Instance of ImageAdapter Class
        gridView.setAdapter(new ImageAdapter(this));

        /**
         * On Click event for Single Gridview Item
         * */
        gridView.setOnItemClickListener(new OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View v,
                    int position, long id) {

                // Sending image id to FullScreenActivity
                Intent i = new Intent(getApplicationContext(),
                        FullImageActivity.class);
                // passing array index
                i.putExtra("id", position);
                startActivity(i);
            }
        });
    }
}

ImageAdapter 类：

package com.example.androidhive;

import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;

public class ImageAdapter extends BaseAdapter {
    private Context mContext;



    // Keep all Images in array
    public Integer[] mThumbIds = {
            // R.string.http_icons_iconarchive_com_icons_martz90_circle_512_android_icon_png
            R.drawable.pic_1, R.drawable.pic_2, R.drawable.pic_3,
            R.drawable.pic_4, R.drawable.pic_5, R.drawable.pic_6,
            R.drawable.pic_7, R.drawable.pic_8, R.drawable.pic_9,
            R.drawable.pic_10, R.drawable.pic_11, R.drawable.pic_12,
            R.drawable.pic_13, R.drawable.pic_14, R.drawable.pic_15 };

    // Constructor
    public ImageAdapter(Context c) {
        mContext = c;
    }

    @Override
    public int getCount() {
        return mThumbIds.length;
    }

    @Override
    public Object getItem(int position) {
        return mThumbIds[position];
    }

    @Override
    public long getItemId(int position) {
        return 0;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ImageView imageView = new ImageView(mContext);
        imageView.setImageResource(mThumbIds[position]);
        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
        imageView.setLayoutParams(new GridView.LayoutParams(70, 70));
        return imageView;
    }

}

我想要的示例：

// Keep all Images in array
    public Integer[] mThumbIds = {          
// how to add images from sd card here
 };

如何将图像从 sd 卡而不是可绘制对象添加到数组。

Answer 1

只需将该特定文件夹中的所有文件名放在ArrayList<String> 中即可。然后稍微改变一下 getView() 让 ImageView 从文件中加载。

Answer 2

你可以从位图创建一个 Drawable，你应该检查一个类似“通用图像加载器”的库，然后使用

Drawable d = new BitmapDrawable(getResources(),bitmap);