如何使位图上的图像更小？答案

【问题标题】：How to make images on Bitmap smaller?如何使位图上的图像更小？
【发布时间】：2021-07-18 09:01:42
【问题描述】：

我正在尝试在 android 上构建一个简单的游戏，在我的主屏幕上设置背景图像和其他图像资源时，它看起来太大了，如下图所示。

图片的实际尺寸是 1920x1080，我希望它适合我的屏幕，如下图所示：

我使用的代码是：

public class PoliceView extends View {

private Bitmap police;
private Bitmap background;
private Paint scorePaint = new Paint();
private Bitmap life[] = new Bitmap[2];

public PoliceView(Context context) {
    super(context);

    police = BitmapFactory.decodeResource(getResources(),R.drawable.police);
    background = BitmapFactory.decodeResource(getResources(),R.drawable.gamebackground);
    

    scorePaint.setColor(Color.BLACK);
    scorePaint.setTextSize(70);
    scorePaint.setTypeface(Typeface.DEFAULT_BOLD);
    scorePaint.setAntiAlias(true);

    life[0] = BitmapFactory.decodeResource(getResources(),R.drawable.heart);
    life[1] = BitmapFactory.decodeResource(getResources(),R.drawable.brokenheart);

}

@Override
protected void onDraw(Canvas canvas) {
    super.onDraw(canvas);

    //The order of draw matters as objects are drawn in this same order
    canvas.drawBitmap(background,0,0,null);
    canvas.drawBitmap(police, 0, 0, null);
    canvas.drawText("Score:",20, 60, scorePaint);
    //Three lives for the police
    canvas.drawBitmap(life[0],580, 10, null);
    canvas.drawBitmap(life[0],680, 10, null);
    canvas.drawBitmap(life[0],780, 10, null);
}}

如何调整图像大小以适应屏幕？？

【问题讨论】：

标签： java android bitmap android-canvas android-bitmap

【解决方案1】：

我使用此代码调整图像大小

        Bitmap tmp = BitmapFactory.decodeFile(mPath);
        ResizeWidth = (int) (your size);
        ResizeHeight = (int) (your size);
    

    Bitmap bitmap = Bitmap.createBitmap(ResizeWidth, ResizeHeight, Bitmap.Config.ARGB_8888);
    Canvas canvas = new Canvas(bitmap);


    Bitmap scaled = Bitmap.createScaledBitmap(tmp, ResizeWidth, ResizeHeight, true);
    int leftOffset = 0;
    int topOffset = 0;
    canvas.drawBitmap(scaled, leftOffset, topOffset, null);

【讨论】：

【解决方案2】：

How to resize bitmap in canvas?

canvas.save();               // Save current canvas params (not only scale)
canvas.scale(scaleX, scaleY);
canvas.restore();            // Restore current canvas params

scale = 1.0f 将绘制相同的可见尺寸位图

【讨论】：

我将它添加到代码的末尾，并将比例值设置为 1.0f，但它仍然没有改变任何东西