如何将图像视图转换成不同的形状？

Question

其实我想把图片转换成图中提到的形状。我在 SO 中尝试了很多类似的问题，但其中 none 很有帮助。您可能建议在 imageView 的前景中使用 drawable，但我必须以编程方式设置前景，这仅对 api>23 有效。谁能帮我解决这个问题？

您可以在图像中看到图像的背景。我想以编程方式将图像转换成那个形状。

即使我尝试使用 Gradient Drawable 但它是徒劳的

代码：

GradientDrawable gradientDrawable= new GradientDrawable();
        float[] radii = new float[8];
        radii[0] = 15; // Goes clockwise, so this is the top left corner start position.
        radii[1] = 15; // top left end position.
        radii[2] = 15;
        radii[3] = 15;
        radii[4]=0;
        radii[5]=0;
        radii[6] = 15;
        radii[7] = 15;
        gradientDrawable.setCornerRadii(radii);
        holder.img.setBackgroundDrawable(gradientDrawable);

Answer 1

您可以通过应用 clipPath 更改 imageView class 的 onDraw 方法：

@Override
protected void onDraw(Canvas canvas) {
    float[] radii = new float[8];
    radii[0] = radius; // Goes clockwise, so this is the top left corner start position.
    radii[1] = radius; // top left end position.
    radii[2] = radius;
    radii[3] = radius;
    // Skipping 4 and 5 because thats the bottom right corner.
    radii[6] = radius;
    radii[7] = radius;
    Path clipPath = new Path();
    clipPath.addRoundRect(new RectF(0, 0, this.getWidth(), this.getHeight()), radii, Path.Direction.CW);
    canvas.clipPath(clipPath);
    super.onDraw(canvas);
}

参考文献：

Answer 2

如果你想创建一个可绘制的图像，那么你可以为不同的角设置不同的半径，比如

<corners
    android:topRightRadius="15dp"
    android:topLeftRadius="15dp"
    android:bottomLeftRadius="15dp"/>

除此之外，您还可以使用 GradientDrawable 创建背景图像并使用 setCornerRadii 可变角半径。

GradientDrawable 示例

GradientDrawable gradientDrawable= new GradientDrawable();
gradientDrawable.setCornerRadii(15,15,15,15,15,15,0,0);

void setCornerRadii (float[] radii)

Specifies radii for each of the 4 corners. For each corner, the array contains 2 values, [X_radius, Y_radius]. The corners are ordered top-left, top-right, bottom-right, bottom-left. This property is honored only when the shape is of type RECTANGLE.

设置颜色使用 gradientDrawable.setColor(YOUR_COLOR) 方法，您可以在那里使用多种颜色进行渐变外观。

此处 (15,15,15,15,15,15,0,0) 建议从左上角开始的所有 4 个角的 X 半径和 Y 半径。

Answer 3

最后我参考了from this and

解决了我的问题

最后 ImageView Class 看起来像：

public class RoundedImageView extends ImageView {

private Path mMaskPath;
private Paint mMaskPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
private int mCornerRadius = 10;

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

    init();
}

public RoundedImageView(Context context, AttributeSet attributeSet) {
    super(context, attributeSet);

    init();
}

public RoundedImageView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);

    init();
}

private void init() {
    ViewCompat.setLayerType(this, ViewCompat.LAYER_TYPE_SOFTWARE, null);
    mMaskPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.CLEAR));
}


public void setCornerRadius(int cornerRadius) {
    mCornerRadius = cornerRadius;
    generateMaskPath(getWidth(), getHeight());
    invalidate();
}

@Override
protected void onSizeChanged(int w, int h, int oldW, int oldH) {
    super.onSizeChanged(w, h, oldW, oldH);

    if (w != oldW || h != oldH) {
        generateMaskPath(w, h);
    }
}

private void generateMaskPath(int w, int h) {
    mMaskPath = new Path();
    float[] radii = new float[8];
    radii[0] = 20; // Goes clockwise, so this is the top left corner start position.
    radii[1] = 20; // top left end position.
    radii[2] = 20;
    radii[3] = 20;
    // Skipping 4 and 5 because thats the bottom right corner.
    radii[6] = 20;
    radii[7] = 20;
    mMaskPath.addRoundRect(new RectF(0,0,w,h), radii, Path.Direction.CW);
    mMaskPath.setFillType(Path.FillType.INVERSE_WINDING);
}

@SuppressLint("WrongConstant")
@Override
protected void onDraw(Canvas canvas) {
    if(canvas.isOpaque()) { // If canvas is opaque, make it transparent
        canvas.saveLayerAlpha(0, 0, canvas.getWidth(), canvas.getHeight(), 255, Canvas.HAS_ALPHA_LAYER_SAVE_FLAG);
    }

    super.onDraw(canvas);

    if(mMaskPath != null) {
        canvas.drawPath(mMaskPath, mMaskPaint);
    }
}
 }

如何将图像视图转换成不同的形状？

How to covert imageview into different shape?

android

imageview

android-shapedrawable