java - 如何以编程方式在android中的数组中添加可绘制的所有图像

Question

我有一个代码可以让我使用可绘制文件夹中的图像，但所有图像都按名称存储在数组中-

我想通过函数以编程方式加载它们并将它们存储在数组中

这是数组:

private int[] theBitmapIds = { R.drawable.elefant_001, R.drawable.elefant_002, R.drawable.elefant_003, R.drawable.elefant_004,
R.drawable.elefant_005, R.drawable.elefant_006, R.drawable.elefant_007,
R.drawable.elefant_008, R.drawable.elefant_009, R.drawable.elefant_010,
R.drawable.elefant_011, R.drawable.elefant_012, R.drawable.elefant_013,
R.drawable.elefant_014, R.drawable.elefant_015, R.drawable.elefant_016,
R.drawable.elefant_017, R.drawable.elefant_018, R.drawable.elefant_019,
R.drawable.elefant_020, R.drawable.elefant_021,R.drawable.elefant_022,
R.drawable.elefant_022, R.drawable.elefant_023,R.drawable.elefant_024,
R.drawable.elefant_025, R.drawable.elefant_026, R.drawable.elefant_027,
R.drawable.elefant_028, R.drawable.elefant_029, R.drawable.elefant_030,
R.drawable.elefant_031, R.drawable.elefant_032, R.drawable.elefant_033,
R.drawable.elefant_034, R.drawable.elefant_035, R.drawable.elefant_036,
R.drawable.elefant_037, R.drawable.elefant_038, R.drawable.elefant_039,
R.drawable.elefant_040};

我是通过函数改的

public int [] theBitmapIds( ) {
    Field[] ID_Fields = R.drawable.class.getFields();
    int[] theBitmapIds = new int[ID_Fields.length];
    for (int i = 0; i < ID_Fields.length; i++) {
        try {
            theBitmapIds[i] = ID_Fields[i].getInt( null );
        } catch (IllegalAccessException e) {
            e.printStackTrace();
        }
    }
    return  theBitmapIds;
}

private int[] theBitmapIds=theBitmapIds( );

但是当我在其他函数中调用数组时，它仍然没有任何内容

public Bitmap getBitmap(int width, int height, int index) {
        Bitmap b = Bitmap.createBitmap(width, height,
                Bitmap.Config.ARGB_8888);
        b.eraseColor(0xFFFFFFFF);
        Canvas c = new Canvas(b);
        Drawable d = getResources().getDrawable(theBitmapIds[index]);

        int margin = 1;
        int border = 1;
        Rect r = new Rect(margin, margin, width - margin, height - margin);

        int imageWidth = r.width() - (border * 2);
        int imageHeight = imageWidth * d.getIntrinsicHeight()
                / d.getIntrinsicWidth();
        if (imageHeight > r.height() - (border * 2)) {
            imageHeight = r.height() - (border * 2);
            imageWidth = imageHeight * d.getIntrinsicWidth()
                    / d.getIntrinsicHeight();
        }

我很困惑，尤其是我是 Java 菜鸟。我如何通过编辑函数或更改这行代码来使此代码工作:

private int[] theBitmapIds=theBitmapIds( );

或

Drawable d = getResources().getDrawable(theBitmapIds[index]);

请有人帮助我!

Answer 1

您可以使用 AssetManager直接加载 Assets 及其路径。

您可以通过调用context.getAssets()获取它的实例。

通过它的 open() 方法，您将能够获得该 Assets 的 InputStream。

然后可以使用BitmapFactory.decodeStream()将其转换为Bitmap。