自定义Android UI和多屏支持

Question

我知道以前曾问过这类问题，但我还没有看到这类问题。 我正在使用android canvas创建自定义android UI。 我已经为其创建了所有必需的可绘制对象，并将它们放置在适当的文件夹中，现在使用以下代码来绘制UI：

public class MainMenuView extends View {

private Bitmap pasteImage;
private Bitmap adventureLetters;
private Bitmap settingsLetters;
private Bitmap quitLetters;
private Bitmap backgroundImage;
private DisplayMetrics metrics;

public MainMenuView(Context context){
    super(context);
    pasteImage = decodeFile(R.drawable.paste, 200, true);
    Log.w("Visina imagea", String.valueOf(pasteImage.getHeight()));
    pasteImage.recycle();
}

public MainMenuView(Context context, AttributeSet attrSet){
    super(context, attrSet);
    metrics = context.getResources().getDisplayMetrics();
    pasteImage = decodeFile(R.drawable.paste, 330, true);
    adventureLetters = decodeFile(R.drawable.adventureletters, 100, true);
    settingsLetters = decodeFile(R.drawable.settingsletters, 100, true);
    quitLetters = decodeFile(R.drawable.quitletters, 50, true);
    Log.w("Je li image null? ", pasteImage == null ? "da" : "ne");
    backgroundImage = decodeFileScaled(R.drawable.toothpastebackground);
    backgroundImage = Bitmap.createScaledBitmap(backgroundImage, metrics.widthPixels - 20, metrics.heightPixels, true);
    //adventureLetters = BitmapFactory.decodeResource(getResources(), R.drawable.adventureletters);
    //settingsLetters = BitmapFactory.decodeResource(getResources(), R.drawable.settingsletters);
    //quitLetters = BitmapFactory.decodeResource(getResources(), R.drawable.quitletters);
}

@Override
protected void onMeasure(int widthMeasure, int heightMeasure){
    setMeasuredDimension(calculateMeasure(widthMeasure), calculateMeasure(heightMeasure));
    Log.w(String.valueOf(calculateMeasure(widthMeasure)), "Izmjereno");
}

private static final int DEFAULT_SIZE = 70;
private int calculateMeasure(int measure) {

    int result = (int)(DEFAULT_SIZE * getResources().getDisplayMetrics().density);
    int specMode = MeasureSpec.getMode(measure);
    int specSize = MeasureSpec.getSize(measure);

    if(specMode == MeasureSpec.EXACTLY) result = specSize;
    else if(specMode == MeasureSpec.AT_MOST){
        result = Math.min(result, specSize);
    }

    return result;
}

@Override
protected void onDraw(Canvas canvas){
    super.onDraw(canvas);
    if(canvas == null) Log.w("Canvas je null", "Da");
    else Log.w("Canvas nije null", "ne");
    Log.w("Usao u onDraw", "u onDraw sam sad");
    canvas.save();
    if(pasteImage == null) Log.w("Slika je null", "null slika");
    canvas.drawBitmap(backgroundImage, 0, 0, null);
    Log.w("Dimenzije slike sirina x visina bg", backgroundImage.getWidth() + " " + backgroundImage.getHeight());
    canvas.drawBitmap(pasteImage, 110, 420, null);
    canvas.drawBitmap(adventureLetters, 50,  60, null);
    canvas.drawBitmap(settingsLetters, 80,  60, null);
    canvas.drawBitmap(quitLetters, 100,  60, null);
    pasteImage.recycle();
    adventureLetters.recycle();
    settingsLetters.recycle();
    quitLetters.recycle();
    canvas.restore();
}

private Bitmap decodeFile(int id, int size, boolean resize){

        //Decode image size
        BitmapFactory.Options o = new BitmapFactory.Options();
        o.inJustDecodeBounds = true;
        BitmapFactory.decodeResource(getResources(), id, o);

        //The new size we want to scale to
        final int REQUIRED_SIZE = size;

        //Find the correct scale value. It should be the power of 2.
        int scale = 1;
        while(o.outWidth/scale/2 >= REQUIRED_SIZE && o.outHeight/scale/2 >= REQUIRED_SIZE)
            scale*=2;

        //Decode with inSampleSize
        BitmapFactory.Options o2 = new BitmapFactory.Options();
        o2.inSampleSize = scale;
        return BitmapFactory.decodeResource(getResources(), id, o2);

}

private Bitmap decodeFileScaled(int id){

    final BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeResource(getResources(), id, options);
    Log.w("Sirina x visina displaya", metrics.widthPixels + "x" +   metrics.heightPixels);
    options.inSampleSize = calculateScale(options, metrics.widthPixels, metrics.heightPixels);

    options.inJustDecodeBounds = false;
    return BitmapFactory.decodeResource(getResources(), id, options);
}

private int calculateScale(BitmapFactory.Options options, int reqWidth, int reqHeight){

    final int rawHeight = options.outHeight;
    final int rawWidth = options.outWidth;
    int inSampleSize = 1;

    if (rawHeight > reqHeight || rawWidth > reqWidth) {

        // Calculate ratios of height and width to requested height and width
        final int heightRatio = Math.round((float) rawHeight / (float) reqHeight);
        final int widthRatio = Math.round((float) rawWidth / (float) reqWidth);

        // Choose the smallest ratio as inSampleSize value, this will guarantee
        // a final image with both dimensions larger than or equal to the
        // requested height and width.
        inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
    }

    return inSampleSize;
}
}

您可以立即看到我正在使用一些硬编码值在屏幕上定位。 您能给我一些如何编码的建议，以便它在每个屏幕上（特别是中尺寸和高尺寸）都应显示。 因为这应该意味着没有模糊的撕裂空白空间等等。 如果您需要更多信息，请在评论中让我知道，非常感谢！

Answer 1

您应该始终在屏幕上使用位置亲戚。 例如：

float left = getScreenSize().x * 0.10f;
float top = getScreenSize().y * 0.10f;

canvas.drawBitmap(pasteImage, left, top, null);

private float getScreenSize() {
     WindowManager windowManager = (WindowManager) getContext.getSystemService(Context.WINDOW_SERVICE);
     Display display = windowManager.getDefaultDisplay();
     Display display = getWindowManager().getDefaultDisplay();
     Point size = new Point();
     display.getSize(size);
     return size;
}

但是，如果要使用绝对值，则应使用dp而不是px。

Resources resources = getResources();

float left = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 140, resources.getDisplayMetrics());

float top = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 140, resources.getDisplayMetrics());

canvas.drawBitmap(pasteImage, left, top, null);