先看看效果圖：
實作思路：擦除圖檔相應的角，然後層疊圖檔，産生傾斜效果
代碼實作：
1、定義屬性
在values檔案夾下的attrs檔案添加以下代碼
2、自定義布局
public class TiltView extends ImageView {
private int imageWidth;//圖檔寬度
private int imageHeight;//圖檔高度
private double angle = 10 * Math.PI / 180;//三角形角度
private int triangleHeight;//三角形高度
private Paint paint;//畫筆
private Path path;//繪制路徑
private int type;//傾斜圖檔的類型
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();
}
//重測大小
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
imageWidth = measureSpec(widthMeasureSpec);
imageHeight = measureSpec(heightMeasureSpec);
setMeasuredDimension(imageWidth, imageHeight); //設定View的大小
triangleHeight = (int) (Math.abs(Math.tan(angle) * imageHeight));
}
//測量長度
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);//建立畫布，并繪制mBitmap
Bitmap mBackBitmap = ((BitmapDrawable) getDrawable()).getBitmap();
mCanvas.drawBitmap(resizeBitmap(mBackBitmap), 0, 0, null);//繪制Bitmap
setTriangle();
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_OUT));
mCanvas.drawPath(path, paint);
canvas.drawBitmap(mBitmap, 0, 0, null);
}
//初始化畫筆
private void initPaint() {
paint = new Paint();
paint.setDither(true);//設定是否使用圖像抖動處理，會使繪制出來的圖檔顔色更加平滑和飽滿，圖像更加清晰
paint.setAntiAlias(true);//設定抗鋸齒
paint.setStrokeWidth(5);
paint.setStyle(Paint.Style.FILL);
paint.setStrokeCap(Paint.Cap.ROUND);
paint.setStrokeJoin(Paint.Join.ROUND);//圓角
}
//設定三角形區域
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;
}
}
//重新調節圖檔大小
private Bitmap resizeBitmap(Bitmap bitmap) {
int width = bitmap.getWidth();
int height = bitmap.getHeight();
// 設定想要的大小
int newWidth = imageWidth;
int newHeight = imageHeight;
// 計算縮放比例
float scaleWidth = ((float) newWidth) / width;
float scaleHeight = ((float) newHeight) / height;
// 取得想要縮放的matrix參數
Matrix matrix = new Matrix();
matrix.postScale(scaleWidth, scaleHeight);
// 得到新的圖檔
return Bitmap.createBitmap(bitmap, 0, 0, width, height, matrix, true);
}
}
3、布局代碼調用
//其中android:layout_marginTop="-15dp"對效果實作有很大的作用
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，希望對大家的學習有所幫助，也希望大家多多支援腳本之家。