先看看效果图：
实现思路：擦除图片相应的角，然后层叠图片，产生倾斜效果
代码实现：
1、定义属性
在values文件夹下的attrs文件添加以下代码
2、自定义布局
public class TiltView extends ImageView {
private int imageWidth;//图片宽度
private int imageHeight;//图片高度
private double angle = 10 * Math.PI / 180;//三角形角度
private int triangleHeight;//三角形高度
private Paint paint;//画笔
private Path path;//绘制路径
private int type;//倾斜图片的类型
public TiltView(Context context) {
this(context, null);
}
public TiltView(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public TiltView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
TypedArray array = context.obtainStyledAttributes(attrs, R.styleable.TiltView);
type = array.getInteger(R.styleable.TiltView_type, 1);
array.recycle();
}
//重测大小
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
imageWidth = measureSpec(widthMeasureSpec);
imageHeight = measureSpec(heightMeasureSpec);
setMeasuredDimension(imageWidth, imageHeight); //设置View的大小
triangleHeight = (int) (Math.abs(Math.tan(angle) * imageHeight));
}
//测量长度
private int measureSpec(int measureSpec) {
int minLength = 200;
int mode = MeasureSpec.getMode(measureSpec);
int length = MeasureSpec.getSize(measureSpec);
if (mode == MeasureSpec.AT_MOST) {
length = Math.min(length, minLength);
}
return length;
}
@Override
protected void onDraw(Canvas canvas) {
initPaint();
Bitmap mBitmap = Bitmap.createBitmap(imageWidth, imageHeight, Bitmap.Config.ARGB_8888); //初始化Bitmap
Canvas mCanvas = new Canvas(mBitmap);//创建画布，并绘制mBitmap
Bitmap mBackBitmap = ((BitmapDrawable) getDrawable()).getBitmap();
mCanvas.drawBitmap(resizeBitmap(mBackBitmap), 0, 0, null);//绘制Bitmap
setTriangle();
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_OUT));
mCanvas.drawPath(path, paint);
canvas.drawBitmap(mBitmap, 0, 0, null);
}
//初始化画笔
private void initPaint() {
paint = new Paint();
paint.setDither(true);//设定是否使用图像抖动处理，会使绘制出来的图片颜色更加平滑和饱满，图像更加清晰
paint.setAntiAlias(true);//设置抗锯齿
paint.setStrokeWidth(5);
paint.setStyle(Paint.Style.FILL);
paint.setStrokeCap(Paint.Cap.ROUND);
paint.setStrokeJoin(Paint.Join.ROUND);//圆角
}
//设置三角形区域
private void setTriangle() {
path = new Path();
switch (type) {
case 1://右下角
path.moveTo(0, imageHeight);
path.lineTo(imageWidth, imageHeight);
path.lineTo(imageWidth, imageHeight - triangleHeight);
path.lineTo(0, imageHeight);
break;
case 2://左上角+左下角
path.moveTo(0, triangleHeight);
path.lineTo(imageWidth, 0);
path.lineTo(0, 0);
path.lineTo(0, imageHeight);
path.lineTo(imageWidth, imageHeight);
path.lineTo(0, imageHeight - triangleHeight);
break;
case 3://右上角+右下角
path.moveTo(imageWidth, triangleHeight);
path.lineTo(0, 0);
path.lineTo(imageWidth, 0);
path.lineTo(imageWidth, imageHeight);
path.lineTo(0, imageHeight);
path.lineTo(imageWidth, imageHeight - triangleHeight);
break;
case 4://右上角
path.moveTo(0, 0);
path.lineTo(imageWidth, 0);
path.lineTo(imageWidth, triangleHeight);
path.lineTo(0, 0);
break;
case 5://左上角
path.moveTo(0, 0);
path.lineTo(imageWidth, 0);
path.lineTo(0, triangleHeight);
path.lineTo(0, 0);
break;
}
}
//重新调节图片大小
private Bitmap resizeBitmap(Bitmap bitmap) {
int width = bitmap.getWidth();
int height = bitmap.getHeight();
// 设置想要的大小
int newWidth = imageWidth;
int newHeight = imageHeight;
// 计算缩放比例
float scaleWidth = ((float) newWidth) / width;
float scaleHeight = ((float) newHeight) / height;
// 取得想要缩放的matrix参数
Matrix matrix = new Matrix();
matrix.postScale(scaleWidth, scaleHeight);
// 得到新的图片
return Bitmap.createBitmap(bitmap, 0, 0, width, height, matrix, true);
}
}
3、布局代码调用
//其中android:layout_marginTop="-15dp"对效果实现有很大的作用
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
android:layout_width="match_parent"
android:layout_height="100dp"
android:src="@drawable/sample_0"
app:type="1" />
android:layout_width="match_parent"
android:layout_height="100dp"
android:layout_marginTop="-15dp"
android:src="@drawable/sample_1"
app:type="2" />
android:layout_width="match_parent"
android:layout_height="100dp"
android:layout_marginTop="-15dp"
android:src="@drawable/sample_2"
app:type="4" />
以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持脚本之家。