我已经收窄这种行为降低到原来的Matrix一个的View的帆布已经被视图的位置转换。但是，如果您Matrix使用Canvas.getMatrix()或，则这并不明显View.getMatrix()。您将从这些调用中获得身份矩阵。
您看到的画布偏移很可能View与屏幕顶部（状态栏，标题栏等）的偏移高度完全相同。
在大多数情况下，您可以使用canvas.concat(matrix)代替canvas.setMatrix(matrix)此用例，这是正确的。如果您确实需要原始矩阵（我在调试时做了），则必须通过View自身的翻译手动对其进行转换Window：
int[] viewLocation = new int[2];
mView.getLocationInWindow(viewLocation);
mOriginalMatrix.setTranslate(viewLocation[0], viewLocation[1]);
以回答评论中的其他问题：
要转换触摸坐标（或任何屏幕坐标）以匹配a的坐标Canvas，只需将所有转换改为aMatrix，并Canvas.concat()在绘制之前每帧使用该矩阵。（或者您可以Canvas像现在一样直接进行所有转换，并Canvas.getMatrix(mMyMatrix)在每次绘制后使用来检索矩阵。不建议使用，但是可以使用。）
然后可以使用矩阵将原始网格边界转换为在屏幕上绘制的边界。本质上，您所做的与Canvas绘制网格时完全相同，将网格的角点转换为屏幕坐标。现在，网格将与触摸事件位于同一坐标系中：
private final Matrix mMyMatrix = new Matrix();
// Assumes that the grid covers the whole View.
private final float[] mOriginalGridCorners = new float[] {
0, 0, // top left (x, y)
getWidth(), getHeight() // bottom right (x, y)
};
private final float[] mTransformedGridCorners = new float[4];
@Override
public boolean onTouchEvent(MotionEvent event) {
if (/* User pans the screen */) {
mMyMatrix.postTranslate(deltaX, deltaY);
}
if (/* User zooms the screen */) {
mMyMatrix.postScale(deltaScale, deltaScale);
}
if (/* User taps the grid */) {
// Transform the original grid corners to where they
// are on the screen (panned and zoomed).
mMyMatrix.mapPoints(mTransformedGridCorners, mOriginalGridCorners);
float gridWidth = mTransformedGridCorners[2] - mTransformedGridCorners[0];
float gridHeight = mTransformedGridCorners[3] - mTransformedGridCorners[1];
// Get the x and y coordinate of the tap inside the
// grid, between 0 and 1.
float x = (event.getX() - mTransformedGridCorners[0]) / gridWidth;
float y = (event.getY() - mTransformedGridCorners[1]) / gridHeight;
// To get the tapped grid cell.
int column = (int)(x * nbrColumns);
int row = (int)(y * nbrRows);
// Or to get the tapped exact pixel in the original grid.
int pixelX = (int)(x * getWidth());
int pixelY = (int)(y * getHeight());
}
return true;
}
@Override
protected void onDraw(Canvas canvas) {
// Each frame, transform your canvas with the matrix.
canvas.save();
canvas.concat(mMyMatrix);
// Draw grid.
grid.draw(canvas);
canvas.restore();
}
或者不推荐使用的方法来获取矩阵，该方法仍然有效，并且可能需要较少的更改：
@Override
protected void onDraw(Canvas canvas) {
canvas.save();
// Transform canvas and draw the grid.
grid.draw(canvas);
// Get the matrix from canvas. Can be used to transform
// corners on the next touch event.
canvas.getMatrix(mMyMatrix);
canvas.restore();
}
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