最近较流行的效果 Android自定义View实现倾斜列表/图片

<resources>  <declare-styleable name="TiltView">    <attr name="type" format="integer" />  </declare-styleable></resources>

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);  }}

//其中android:layout_marginTop="-15dp"对效果实现有很大的作用<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"  xmlns:app="http://schemas.android.com/apk/res-auto"  android:layout_width="match_parent"  android:layout_height="match_parent"  android:orientation="vertical">  <com.pengkv.may.widget.TiltView    android:layout_width="match_parent"    android:layout_height="100dp"    android:src="@drawable/sample_0"    app:type="1" />  <com.pengkv.may.widget.TiltView    android:layout_width="match_parent"    android:layout_height="100dp"    android:layout_marginTop="-15dp"    android:src="@drawable/sample_1"    app:type="2" />  <com.pengkv.may.widget.TiltView    android:layout_width="match_parent"    android:layout_height="100dp"    android:layout_marginTop="-15dp"    android:src="@drawable/sample_2"    app:type="4" /></LinearLayout>